[PATCH 3/5] scripts: Add qoiconv to convert png to qoi
Ahmad Fatoum
a.fatoum at pengutronix.de
Fri Jan 14 02:29:58 PST 2022
On 10.01.22 23:12, Jules Maselbas wrote:
> ImageMagick will eventually support the qoi image format, in the
> mean time add a png to qoi conversion program.
>
> Signed-off-by: Jules Maselbas <jmaselbas at kalray.eu>
> ---
> scripts/Kconfig | 5 +
> scripts/Makefile | 1 +
> scripts/qoiconv.c | 91 +
> scripts/stb_image.h | 7756 +++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 7853 insertions(+)
> create mode 100644 scripts/qoiconv.c
> create mode 100644 scripts/stb_image.h
>
> diff --git a/scripts/Kconfig b/scripts/Kconfig
> index 9b744deba9..747f665e02 100644
> --- a/scripts/Kconfig
> +++ b/scripts/Kconfig
> @@ -110,6 +110,11 @@ config RK_USB_LOADER
>
> You need libusb-1.0 to compile this tool.
>
> +config QOICONV
> + bool "QOI image format conversion" if COMPILE_HOST_TOOLS
> + help
> + This enable converting png to qoi images to generate boot logo.
> +
> endmenu
>
> menu "Target Tools"
> diff --git a/scripts/Makefile b/scripts/Makefile
> index dc5fa75f90..cbaf2d55ff 100644
> --- a/scripts/Makefile
> +++ b/scripts/Makefile
> @@ -8,6 +8,7 @@ hostprogs-always-y += fix_size
> hostprogs-always-y += bareboxenv
> hostprogs-always-y += bareboxcrc32
> hostprogs-always-y += kernel-install
> +hostprogs-always-$(CONFIG_QOICONV) += qoiconv
> hostprogs-always-$(CONFIG_CRYPTO_RSA_BUILTIN_KEYS) += rsatoc
> HOSTCFLAGS_rsatoc = `pkg-config --cflags openssl`
> HOSTLDLIBS_rsatoc = `pkg-config --libs openssl`
> diff --git a/scripts/qoiconv.c b/scripts/qoiconv.c
> new file mode 100644
> index 0000000000..010c70ead0
> --- /dev/null
> +++ b/scripts/qoiconv.c
> @@ -0,0 +1,91 @@
> +/*
> +
> +Command line tool to convert between png <> qoi format
> +
> +Requires "stb_image.h" and "stb_image_write.h"
> +Compile with:
> + gcc qoiconv.c -std=c99 -O3 -o qoiconv
> +
> +Dominic Szablewski - https://phoboslab.org
> +
> +
> +-- LICENSE: The MIT License(MIT)
> +
> +Copyright(c) 2021 Dominic Szablewski
> +
> +Permission is hereby granted, free of charge, to any person obtaining a copy of
> +this software and associated documentation files(the "Software"), to deal in
> +the Software without restriction, including without limitation the rights to
> +use, copy, modify, merge, publish, distribute, sublicense, and / or sell copies
> +of the Software, and to permit persons to whom the Software is furnished to do
> +so, subject to the following conditions :
> +The above copyright notice and this permission notice shall be included in all
> +copies or substantial portions of the Software.
> +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
> +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
> +SOFTWARE.
> +
> +*/
Can you not reuse the header added in the previous commit?
> +
> +
> +#define STB_IMAGE_IMPLEMENTATION
> +#define STBI_ONLY_PNG
> +#define STBI_NO_LINEAR
> +#include "stb_image.h"
> +
> +#define QOI_IMPLEMENTATION
> +#include "../lib/gui/qoi.h"
> +
> +#define STR_ENDS_WITH(S, E) (strcmp(S + strlen(S) - (sizeof(E)-1), E) == 0)
> +
> +int main(int argc, char **argv) {
> + if (argc < 3) {
> + puts("Usage: qoiconv <infile> <outfile>");
> + puts("Examples:");
> + puts(" qoiconv input.png output.qoi");
> + puts(" qoiconv input.qoi output.png");
> + exit(1);
> + }
> +
> + void *pixels = NULL;
> + int w, h, channels;
> + if (STR_ENDS_WITH(argv[1], ".png")) {
> + if(!stbi_info(argv[1], &w, &h, &channels)) {
> + printf("Couldn't read header %s\n", argv[1]);
> + exit(1);
> + }
> +
> + // Force all odd encodings to be RGBA
> + if(channels != 3) {
> + channels = 4;
> + }
> +
> + pixels = (void *)stbi_load(argv[1], &w, &h, NULL, channels);
> + }
> + if (pixels == NULL) {
> + printf("Couldn't load/decode %s\n", argv[1]);
> + exit(1);
> + }
> +
> + int encoded = 0;
> + if (STR_ENDS_WITH(argv[2], ".qoi")) {
> + encoded = qoi_write(argv[2], pixels, &(qoi_desc){
> + .width = w,
> + .height = h,
> + .channels = channels,
> + .colorspace = QOI_SRGB
> + });
> + }
> +
> + if (!encoded) {
> + printf("Couldn't write/encode %s\n", argv[2]);
> + exit(1);
> + }
> +
> + free(pixels);
> + return 0;
> +}
> diff --git a/scripts/stb_image.h b/scripts/stb_image.h
> new file mode 100644
> index 0000000000..742fac74f7
> --- /dev/null
> +++ b/scripts/stb_image.h
> @@ -0,0 +1,7756 @@
> +/* stb_image - v2.26 - public domain image loader - http://nothings.org/stb
> + no warranty implied; use at your own risk
> +
> + Do this:
> + #define STB_IMAGE_IMPLEMENTATION
> + before you include this file in *one* C or C++ file to create the implementation.
> +
> + // i.e. it should look like this:
> + #include ...
> + #include ...
> + #include ...
> + #define STB_IMAGE_IMPLEMENTATION
> + #include "stb_image.h"
> +
> + You can #define STBI_ASSERT(x) before the #include to avoid using assert.h.
> + And #define STBI_MALLOC, STBI_REALLOC, and STBI_FREE to avoid using malloc,realloc,free
> +
> +
> + QUICK NOTES:
> + Primarily of interest to game developers and other people who can
> + avoid problematic images and only need the trivial interface
> +
> + JPEG baseline & progressive (12 bpc/arithmetic not supported, same as stock IJG lib)
> + PNG 1/2/4/8/16-bit-per-channel
> +
> + TGA (not sure what subset, if a subset)
> + BMP non-1bpp, non-RLE
> + PSD (composited view only, no extra channels, 8/16 bit-per-channel)
> +
> + GIF (*comp always reports as 4-channel)
> + HDR (radiance rgbE format)
> + PIC (Softimage PIC)
> + PNM (PPM and PGM binary only)
> +
> + Animated GIF still needs a proper API, but here's one way to do it:
> + http://gist.github.com/urraka/685d9a6340b26b830d49
> +
> + - decode from memory or through FILE (define STBI_NO_STDIO to remove code)
> + - decode from arbitrary I/O callbacks
> + - SIMD acceleration on x86/x64 (SSE2) and ARM (NEON)
> +
> + Full documentation under "DOCUMENTATION" below.
> +
> +
> +LICENSE
> +
> + See end of file for license information.
> +
> +RECENT REVISION HISTORY:
> +
> + 2.26 (2020-07-13) many minor fixes
> + 2.25 (2020-02-02) fix warnings
> + 2.24 (2020-02-02) fix warnings; thread-local failure_reason and flip_vertically
> + 2.23 (2019-08-11) fix clang static analysis warning
> + 2.22 (2019-03-04) gif fixes, fix warnings
> + 2.21 (2019-02-25) fix typo in comment
> + 2.20 (2019-02-07) support utf8 filenames in Windows; fix warnings and platform ifdefs
> + 2.19 (2018-02-11) fix warning
> + 2.18 (2018-01-30) fix warnings
> + 2.17 (2018-01-29) bugfix, 1-bit BMP, 16-bitness query, fix warnings
> + 2.16 (2017-07-23) all functions have 16-bit variants; optimizations; bugfixes
> + 2.15 (2017-03-18) fix png-1,2,4; all Imagenet JPGs; no runtime SSE detection on GCC
> + 2.14 (2017-03-03) remove deprecated STBI_JPEG_OLD; fixes for Imagenet JPGs
> + 2.13 (2016-12-04) experimental 16-bit API, only for PNG so far; fixes
> + 2.12 (2016-04-02) fix typo in 2.11 PSD fix that caused crashes
> + 2.11 (2016-04-02) 16-bit PNGS; enable SSE2 in non-gcc x64
> + RGB-format JPEG; remove white matting in PSD;
> + allocate large structures on the stack;
> + correct channel count for PNG & BMP
> + 2.10 (2016-01-22) avoid warning introduced in 2.09
> + 2.09 (2016-01-16) 16-bit TGA; comments in PNM files; STBI_REALLOC_SIZED
> +
> + See end of file for full revision history.
> +
> +
> + ============================ Contributors =========================
> +
> + Image formats Extensions, features
> + Sean Barrett (jpeg, png, bmp) Jetro Lauha (stbi_info)
> + Nicolas Schulz (hdr, psd) Martin "SpartanJ" Golini (stbi_info)
> + Jonathan Dummer (tga) James "moose2000" Brown (iPhone PNG)
> + Jean-Marc Lienher (gif) Ben "Disch" Wenger (io callbacks)
> + Tom Seddon (pic) Omar Cornut (1/2/4-bit PNG)
> + Thatcher Ulrich (psd) Nicolas Guillemot (vertical flip)
> + Ken Miller (pgm, ppm) Richard Mitton (16-bit PSD)
> + github:urraka (animated gif) Junggon Kim (PNM comments)
> + Christopher Forseth (animated gif) Daniel Gibson (16-bit TGA)
> + socks-the-fox (16-bit PNG)
> + Jeremy Sawicki (handle all ImageNet JPGs)
> + Optimizations & bugfixes Mikhail Morozov (1-bit BMP)
> + Fabian "ryg" Giesen Anael Seghezzi (is-16-bit query)
> + Arseny Kapoulkine
> + John-Mark Allen
> + Carmelo J Fdez-Aguera
> +
> + Bug & warning fixes
> + Marc LeBlanc David Woo Guillaume George Martins Mozeiko
> + Christpher Lloyd Jerry Jansson Joseph Thomson Blazej Dariusz Roszkowski
> + Phil Jordan Dave Moore Roy Eltham
> + Hayaki Saito Nathan Reed Won Chun
> + Luke Graham Johan Duparc Nick Verigakis the Horde3D community
> + Thomas Ruf Ronny Chevalier github:rlyeh
> + Janez Zemva John Bartholomew Michal Cichon github:romigrou
> + Jonathan Blow Ken Hamada Tero Hanninen github:svdijk
> + Laurent Gomila Cort Stratton github:snagar
> + Aruelien Pocheville Sergio Gonzalez Thibault Reuille github:Zelex
> + Cass Everitt Ryamond Barbiero github:grim210
> + Paul Du Bois Engin Manap Aldo Culquicondor github:sammyhw
> + Philipp Wiesemann Dale Weiler Oriol Ferrer Mesia github:phprus
> + Josh Tobin Matthew Gregan github:poppolopoppo
> + Julian Raschke Gregory Mullen Christian Floisand github:darealshinji
> + Baldur Karlsson Kevin Schmidt JR Smith github:Michaelangel007
> + Brad Weinberger Matvey Cherevko [reserved]
> + Luca Sas Alexander Veselov Zack Middleton [reserved]
> + Ryan C. Gordon [reserved] [reserved]
> + DO NOT ADD YOUR NAME HERE
> +
> + To add your name to the credits, pick a random blank space in the middle and fill it.
> + 80% of merge conflicts on stb PRs are due to people adding their name at the end
> + of the credits.
> +*/
> +
> +#ifndef STBI_INCLUDE_STB_IMAGE_H
> +#define STBI_INCLUDE_STB_IMAGE_H
> +
> +// DOCUMENTATION
> +//
> +// Limitations:
> +// - no 12-bit-per-channel JPEG
> +// - no JPEGs with arithmetic coding
> +// - GIF always returns *comp=4
> +//
> +// Basic usage (see HDR discussion below for HDR usage):
> +// int x,y,n;
> +// unsigned char *data = stbi_load(filename, &x, &y, &n, 0);
> +// // ... process data if not NULL ...
> +// // ... x = width, y = height, n = # 8-bit components per pixel ...
> +// // ... replace '0' with '1'..'4' to force that many components per pixel
> +// // ... but 'n' will always be the number that it would have been if you said 0
> +// stbi_image_free(data)
> +//
> +// Standard parameters:
> +// int *x -- outputs image width in pixels
> +// int *y -- outputs image height in pixels
> +// int *channels_in_file -- outputs # of image components in image file
> +// int desired_channels -- if non-zero, # of image components requested in result
> +//
> +// The return value from an image loader is an 'unsigned char *' which points
> +// to the pixel data, or NULL on an allocation failure or if the image is
> +// corrupt or invalid. The pixel data consists of *y scanlines of *x pixels,
> +// with each pixel consisting of N interleaved 8-bit components; the first
> +// pixel pointed to is top-left-most in the image. There is no padding between
> +// image scanlines or between pixels, regardless of format. The number of
> +// components N is 'desired_channels' if desired_channels is non-zero, or
> +// *channels_in_file otherwise. If desired_channels is non-zero,
> +// *channels_in_file has the number of components that _would_ have been
> +// output otherwise. E.g. if you set desired_channels to 4, you will always
> +// get RGBA output, but you can check *channels_in_file to see if it's trivially
> +// opaque because e.g. there were only 3 channels in the source image.
> +//
> +// An output image with N components has the following components interleaved
> +// in this order in each pixel:
> +//
> +// N=#comp components
> +// 1 grey
> +// 2 grey, alpha
> +// 3 red, green, blue
> +// 4 red, green, blue, alpha
> +//
> +// If image loading fails for any reason, the return value will be NULL,
> +// and *x, *y, *channels_in_file will be unchanged. The function
> +// stbi_failure_reason() can be queried for an extremely brief, end-user
> +// unfriendly explanation of why the load failed. Define STBI_NO_FAILURE_STRINGS
> +// to avoid compiling these strings at all, and STBI_FAILURE_USERMSG to get slightly
> +// more user-friendly ones.
> +//
> +// Paletted PNG, BMP, GIF, and PIC images are automatically depalettized.
> +//
> +// ===========================================================================
> +//
> +// UNICODE:
> +//
> +// If compiling for Windows and you wish to use Unicode filenames, compile
> +// with
> +// #define STBI_WINDOWS_UTF8
> +// and pass utf8-encoded filenames. Call stbi_convert_wchar_to_utf8 to convert
> +// Windows wchar_t filenames to utf8.
> +//
> +// ===========================================================================
> +//
> +// Philosophy
> +//
> +// stb libraries are designed with the following priorities:
> +//
> +// 1. easy to use
> +// 2. easy to maintain
> +// 3. good performance
> +//
> +// Sometimes I let "good performance" creep up in priority over "easy to maintain",
> +// and for best performance I may provide less-easy-to-use APIs that give higher
> +// performance, in addition to the easy-to-use ones. Nevertheless, it's important
> +// to keep in mind that from the standpoint of you, a client of this library,
> +// all you care about is #1 and #3, and stb libraries DO NOT emphasize #3 above all.
> +//
> +// Some secondary priorities arise directly from the first two, some of which
> +// provide more explicit reasons why performance can't be emphasized.
> +//
> +// - Portable ("ease of use")
> +// - Small source code footprint ("easy to maintain")
> +// - No dependencies ("ease of use")
> +//
> +// ===========================================================================
> +//
> +// I/O callbacks
> +//
> +// I/O callbacks allow you to read from arbitrary sources, like packaged
> +// files or some other source. Data read from callbacks are processed
> +// through a small internal buffer (currently 128 bytes) to try to reduce
> +// overhead.
> +//
> +// The three functions you must define are "read" (reads some bytes of data),
> +// "skip" (skips some bytes of data), "eof" (reports if the stream is at the end).
> +//
> +// ===========================================================================
> +//
> +// SIMD support
> +//
> +// The JPEG decoder will try to automatically use SIMD kernels on x86 when
> +// supported by the compiler. For ARM Neon support, you must explicitly
> +// request it.
> +//
> +// (The old do-it-yourself SIMD API is no longer supported in the current
> +// code.)
> +//
> +// On x86, SSE2 will automatically be used when available based on a run-time
> +// test; if not, the generic C versions are used as a fall-back. On ARM targets,
> +// the typical path is to have separate builds for NEON and non-NEON devices
> +// (at least this is true for iOS and Android). Therefore, the NEON support is
> +// toggled by a build flag: define STBI_NEON to get NEON loops.
> +//
> +// If for some reason you do not want to use any of SIMD code, or if
> +// you have issues compiling it, you can disable it entirely by
> +// defining STBI_NO_SIMD.
> +//
> +// ===========================================================================
> +//
> +// HDR image support (disable by defining STBI_NO_HDR)
> +//
> +// stb_image supports loading HDR images in general, and currently the Radiance
> +// .HDR file format specifically. You can still load any file through the existing
> +// interface; if you attempt to load an HDR file, it will be automatically remapped
> +// to LDR, assuming gamma 2.2 and an arbitrary scale factor defaulting to 1;
> +// both of these constants can be reconfigured through this interface:
> +//
> +// stbi_hdr_to_ldr_gamma(2.2f);
> +// stbi_hdr_to_ldr_scale(1.0f);
> +//
> +// (note, do not use _inverse_ constants; stbi_image will invert them
> +// appropriately).
> +//
> +// Additionally, there is a new, parallel interface for loading files as
> +// (linear) floats to preserve the full dynamic range:
> +//
> +// float *data = stbi_loadf(filename, &x, &y, &n, 0);
> +//
> +// If you load LDR images through this interface, those images will
> +// be promoted to floating point values, run through the inverse of
> +// constants corresponding to the above:
> +//
> +// stbi_ldr_to_hdr_scale(1.0f);
> +// stbi_ldr_to_hdr_gamma(2.2f);
> +//
> +// Finally, given a filename (or an open file or memory block--see header
> +// file for details) containing image data, you can query for the "most
> +// appropriate" interface to use (that is, whether the image is HDR or
> +// not), using:
> +//
> +// stbi_is_hdr(char *filename);
> +//
> +// ===========================================================================
> +//
> +// iPhone PNG support:
> +//
> +// By default we convert iphone-formatted PNGs back to RGB, even though
> +// they are internally encoded differently. You can disable this conversion
> +// by calling stbi_convert_iphone_png_to_rgb(0), in which case
> +// you will always just get the native iphone "format" through (which
> +// is BGR stored in RGB).
> +//
> +// Call stbi_set_unpremultiply_on_load(1) as well to force a divide per
> +// pixel to remove any premultiplied alpha *only* if the image file explicitly
> +// says there's premultiplied data (currently only happens in iPhone images,
> +// and only if iPhone convert-to-rgb processing is on).
> +//
> +// ===========================================================================
> +//
> +// ADDITIONAL CONFIGURATION
> +//
> +// - You can suppress implementation of any of the decoders to reduce
> +// your code footprint by #defining one or more of the following
> +// symbols before creating the implementation.
> +//
> +// STBI_NO_JPEG
> +// STBI_NO_PNG
> +// STBI_NO_BMP
> +// STBI_NO_PSD
> +// STBI_NO_TGA
> +// STBI_NO_GIF
> +// STBI_NO_HDR
> +// STBI_NO_PIC
> +// STBI_NO_PNM (.ppm and .pgm)
> +//
> +// - You can request *only* certain decoders and suppress all other ones
> +// (this will be more forward-compatible, as addition of new decoders
> +// doesn't require you to disable them explicitly):
> +//
> +// STBI_ONLY_JPEG
> +// STBI_ONLY_PNG
> +// STBI_ONLY_BMP
> +// STBI_ONLY_PSD
> +// STBI_ONLY_TGA
> +// STBI_ONLY_GIF
> +// STBI_ONLY_HDR
> +// STBI_ONLY_PIC
> +// STBI_ONLY_PNM (.ppm and .pgm)
> +//
> +// - If you use STBI_NO_PNG (or _ONLY_ without PNG), and you still
> +// want the zlib decoder to be available, #define STBI_SUPPORT_ZLIB
> +//
> +// - If you define STBI_MAX_DIMENSIONS, stb_image will reject images greater
> +// than that size (in either width or height) without further processing.
> +// This is to let programs in the wild set an upper bound to prevent
> +// denial-of-service attacks on untrusted data, as one could generate a
> +// valid image of gigantic dimensions and force stb_image to allocate a
> +// huge block of memory and spend disproportionate time decoding it. By
> +// default this is set to (1 << 24), which is 16777216, but that's still
> +// very big.
> +
> +#ifndef STBI_NO_STDIO
> +#include <stdio.h>
> +#endif // STBI_NO_STDIO
> +
> +#define STBI_VERSION 1
> +
> +enum
> +{
> + STBI_default = 0, // only used for desired_channels
> +
> + STBI_grey = 1,
> + STBI_grey_alpha = 2,
> + STBI_rgb = 3,
> + STBI_rgb_alpha = 4
> +};
> +
> +#include <stdlib.h>
> +typedef unsigned char stbi_uc;
> +typedef unsigned short stbi_us;
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +#ifndef STBIDEF
> +#ifdef STB_IMAGE_STATIC
> +#define STBIDEF static
> +#else
> +#define STBIDEF extern
> +#endif
> +#endif
> +
> +//////////////////////////////////////////////////////////////////////////////
> +//
> +// PRIMARY API - works on images of any type
> +//
> +
> +//
> +// load image by filename, open file, or memory buffer
> +//
> +
> +typedef struct
> +{
> + int (*read) (void *user,char *data,int size); // fill 'data' with 'size' bytes. return number of bytes actually read
> + void (*skip) (void *user,int n); // skip the next 'n' bytes, or 'unget' the last -n bytes if negative
> + int (*eof) (void *user); // returns nonzero if we are at end of file/data
> +} stbi_io_callbacks;
> +
> +////////////////////////////////////
> +//
> +// 8-bits-per-channel interface
> +//
> +
> +STBIDEF stbi_uc *stbi_load_from_memory (stbi_uc const *buffer, int len , int *x, int *y, int *channels_in_file, int desired_channels);
> +STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk , void *user, int *x, int *y, int *channels_in_file, int desired_channels);
> +
> +#ifndef STBI_NO_STDIO
> +STBIDEF stbi_uc *stbi_load (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels);
> +STBIDEF stbi_uc *stbi_load_from_file (FILE *f, int *x, int *y, int *channels_in_file, int desired_channels);
> +// for stbi_load_from_file, file pointer is left pointing immediately after image
> +#endif
> +
> +#ifndef STBI_NO_GIF
> +STBIDEF stbi_uc *stbi_load_gif_from_memory(stbi_uc const *buffer, int len, int **delays, int *x, int *y, int *z, int *comp, int req_comp);
> +#endif
> +
> +#ifdef STBI_WINDOWS_UTF8
> +STBIDEF int stbi_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input);
> +#endif
> +
> +////////////////////////////////////
> +//
> +// 16-bits-per-channel interface
> +//
> +
> +STBIDEF stbi_us *stbi_load_16_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels);
> +STBIDEF stbi_us *stbi_load_16_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *channels_in_file, int desired_channels);
> +
> +#ifndef STBI_NO_STDIO
> +STBIDEF stbi_us *stbi_load_16 (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels);
> +STBIDEF stbi_us *stbi_load_from_file_16(FILE *f, int *x, int *y, int *channels_in_file, int desired_channels);
> +#endif
> +
> +////////////////////////////////////
> +//
> +// float-per-channel interface
> +//
> +#ifndef STBI_NO_LINEAR
> + STBIDEF float *stbi_loadf_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels);
> + STBIDEF float *stbi_loadf_from_callbacks (stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *channels_in_file, int desired_channels);
> +
> + #ifndef STBI_NO_STDIO
> + STBIDEF float *stbi_loadf (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels);
> + STBIDEF float *stbi_loadf_from_file (FILE *f, int *x, int *y, int *channels_in_file, int desired_channels);
> + #endif
> +#endif
> +
> +#ifndef STBI_NO_HDR
> + STBIDEF void stbi_hdr_to_ldr_gamma(float gamma);
> + STBIDEF void stbi_hdr_to_ldr_scale(float scale);
> +#endif // STBI_NO_HDR
> +
> +#ifndef STBI_NO_LINEAR
> + STBIDEF void stbi_ldr_to_hdr_gamma(float gamma);
> + STBIDEF void stbi_ldr_to_hdr_scale(float scale);
> +#endif // STBI_NO_LINEAR
> +
> +// stbi_is_hdr is always defined, but always returns false if STBI_NO_HDR
> +STBIDEF int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user);
> +STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len);
> +#ifndef STBI_NO_STDIO
> +STBIDEF int stbi_is_hdr (char const *filename);
> +STBIDEF int stbi_is_hdr_from_file(FILE *f);
> +#endif // STBI_NO_STDIO
> +
> +
> +// get a VERY brief reason for failure
> +// on most compilers (and ALL modern mainstream compilers) this is threadsafe
> +STBIDEF const char *stbi_failure_reason (void);
> +
> +// free the loaded image -- this is just free()
> +STBIDEF void stbi_image_free (void *retval_from_stbi_load);
> +
> +// get image dimensions & components without fully decoding
> +STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
> +STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp);
> +STBIDEF int stbi_is_16_bit_from_memory(stbi_uc const *buffer, int len);
> +STBIDEF int stbi_is_16_bit_from_callbacks(stbi_io_callbacks const *clbk, void *user);
> +
> +#ifndef STBI_NO_STDIO
> +STBIDEF int stbi_info (char const *filename, int *x, int *y, int *comp);
> +STBIDEF int stbi_info_from_file (FILE *f, int *x, int *y, int *comp);
> +STBIDEF int stbi_is_16_bit (char const *filename);
> +STBIDEF int stbi_is_16_bit_from_file(FILE *f);
> +#endif
> +
> +
> +
> +// for image formats that explicitly notate that they have premultiplied alpha,
> +// we just return the colors as stored in the file. set this flag to force
> +// unpremultiplication. results are undefined if the unpremultiply overflow.
> +STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply);
> +
> +// indicate whether we should process iphone images back to canonical format,
> +// or just pass them through "as-is"
> +STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert);
> +
> +// flip the image vertically, so the first pixel in the output array is the bottom left
> +STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip);
> +
> +// as above, but only applies to images loaded on the thread that calls the function
> +// this function is only available if your compiler supports thread-local variables;
> +// calling it will fail to link if your compiler doesn't
> +STBIDEF void stbi_set_flip_vertically_on_load_thread(int flag_true_if_should_flip);
> +
> +// ZLIB client - used by PNG, available for other purposes
> +
> +STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen);
> +STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header);
> +STBIDEF char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen);
> +STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
> +
> +STBIDEF char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen);
> +STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
> +
> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +//
> +//
> +//// end header file /////////////////////////////////////////////////////
> +#endif // STBI_INCLUDE_STB_IMAGE_H
> +
> +#ifdef STB_IMAGE_IMPLEMENTATION
> +
> +#if defined(STBI_ONLY_JPEG) || defined(STBI_ONLY_PNG) || defined(STBI_ONLY_BMP) \
> + || defined(STBI_ONLY_TGA) || defined(STBI_ONLY_GIF) || defined(STBI_ONLY_PSD) \
> + || defined(STBI_ONLY_HDR) || defined(STBI_ONLY_PIC) || defined(STBI_ONLY_PNM) \
> + || defined(STBI_ONLY_ZLIB)
> + #ifndef STBI_ONLY_JPEG
> + #define STBI_NO_JPEG
> + #endif
> + #ifndef STBI_ONLY_PNG
> + #define STBI_NO_PNG
> + #endif
> + #ifndef STBI_ONLY_BMP
> + #define STBI_NO_BMP
> + #endif
> + #ifndef STBI_ONLY_PSD
> + #define STBI_NO_PSD
> + #endif
> + #ifndef STBI_ONLY_TGA
> + #define STBI_NO_TGA
> + #endif
> + #ifndef STBI_ONLY_GIF
> + #define STBI_NO_GIF
> + #endif
> + #ifndef STBI_ONLY_HDR
> + #define STBI_NO_HDR
> + #endif
> + #ifndef STBI_ONLY_PIC
> + #define STBI_NO_PIC
> + #endif
> + #ifndef STBI_ONLY_PNM
> + #define STBI_NO_PNM
> + #endif
> +#endif
> +
> +#if defined(STBI_NO_PNG) && !defined(STBI_SUPPORT_ZLIB) && !defined(STBI_NO_ZLIB)
> +#define STBI_NO_ZLIB
> +#endif
> +
> +
> +#include <stdarg.h>
> +#include <stddef.h> // ptrdiff_t on osx
> +#include <stdlib.h>
> +#include <string.h>
> +#include <limits.h>
> +
> +#if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR)
> +#include <math.h> // ldexp, pow
> +#endif
> +
> +#ifndef STBI_NO_STDIO
> +#include <stdio.h>
> +#endif
> +
> +#ifndef STBI_ASSERT
> +#include <assert.h>
> +#define STBI_ASSERT(x) assert(x)
> +#endif
> +
> +#ifdef __cplusplus
> +#define STBI_EXTERN extern "C"
> +#else
> +#define STBI_EXTERN extern
> +#endif
> +
> +
> +#ifndef _MSC_VER
> + #ifdef __cplusplus
> + #define stbi_inline inline
> + #else
> + #define stbi_inline
> + #endif
> +#else
> + #define stbi_inline __forceinline
> +#endif
> +
> +#ifndef STBI_NO_THREAD_LOCALS
> + #if defined(__cplusplus) && __cplusplus >= 201103L
> + #define STBI_THREAD_LOCAL thread_local
> + #elif defined(__GNUC__) && __GNUC__ < 5
> + #define STBI_THREAD_LOCAL __thread
> + #elif defined(_MSC_VER)
> + #define STBI_THREAD_LOCAL __declspec(thread)
> + #elif defined (__STDC_VERSION__) && __STDC_VERSION__ >= 201112L && !defined(__STDC_NO_THREADS__)
> + #define STBI_THREAD_LOCAL _Thread_local
> + #endif
> +
> + #ifndef STBI_THREAD_LOCAL
> + #if defined(__GNUC__)
> + #define STBI_THREAD_LOCAL __thread
> + #endif
> + #endif
> +#endif
> +
> +#ifdef _MSC_VER
> +typedef unsigned short stbi__uint16;
> +typedef signed short stbi__int16;
> +typedef unsigned int stbi__uint32;
> +typedef signed int stbi__int32;
> +#else
> +#include <stdint.h>
> +typedef uint16_t stbi__uint16;
> +typedef int16_t stbi__int16;
> +typedef uint32_t stbi__uint32;
> +typedef int32_t stbi__int32;
> +#endif
> +
> +// should produce compiler error if size is wrong
> +typedef unsigned char validate_uint32[sizeof(stbi__uint32)==4 ? 1 : -1];
> +
> +#ifdef _MSC_VER
> +#define STBI_NOTUSED(v) (void)(v)
> +#else
> +#define STBI_NOTUSED(v) (void)sizeof(v)
> +#endif
> +
> +#ifdef _MSC_VER
> +#define STBI_HAS_LROTL
> +#endif
> +
> +#ifdef STBI_HAS_LROTL
> + #define stbi_lrot(x,y) _lrotl(x,y)
> +#else
> + #define stbi_lrot(x,y) (((x) << (y)) | ((x) >> (32 - (y))))
> +#endif
> +
> +#if defined(STBI_MALLOC) && defined(STBI_FREE) && (defined(STBI_REALLOC) || defined(STBI_REALLOC_SIZED))
> +// ok
> +#elif !defined(STBI_MALLOC) && !defined(STBI_FREE) && !defined(STBI_REALLOC) && !defined(STBI_REALLOC_SIZED)
> +// ok
> +#else
> +#error "Must define all or none of STBI_MALLOC, STBI_FREE, and STBI_REALLOC (or STBI_REALLOC_SIZED)."
> +#endif
> +
> +#ifndef STBI_MALLOC
> +#define STBI_MALLOC(sz) malloc(sz)
> +#define STBI_REALLOC(p,newsz) realloc(p,newsz)
> +#define STBI_FREE(p) free(p)
> +#endif
> +
> +#ifndef STBI_REALLOC_SIZED
> +#define STBI_REALLOC_SIZED(p,oldsz,newsz) STBI_REALLOC(p,newsz)
> +#endif
> +
> +// x86/x64 detection
> +#if defined(__x86_64__) || defined(_M_X64)
> +#define STBI__X64_TARGET
> +#elif defined(__i386) || defined(_M_IX86)
> +#define STBI__X86_TARGET
> +#endif
> +
> +#if defined(__GNUC__) && defined(STBI__X86_TARGET) && !defined(__SSE2__) && !defined(STBI_NO_SIMD)
> +// gcc doesn't support sse2 intrinsics unless you compile with -msse2,
> +// which in turn means it gets to use SSE2 everywhere. This is unfortunate,
> +// but previous attempts to provide the SSE2 functions with runtime
> +// detection caused numerous issues. The way architecture extensions are
> +// exposed in GCC/Clang is, sadly, not really suited for one-file libs.
> +// New behavior: if compiled with -msse2, we use SSE2 without any
> +// detection; if not, we don't use it at all.
> +#define STBI_NO_SIMD
> +#endif
> +
> +#if defined(__MINGW32__) && defined(STBI__X86_TARGET) && !defined(STBI_MINGW_ENABLE_SSE2) && !defined(STBI_NO_SIMD)
> +// Note that __MINGW32__ doesn't actually mean 32-bit, so we have to avoid STBI__X64_TARGET
> +//
> +// 32-bit MinGW wants ESP to be 16-byte aligned, but this is not in the
> +// Windows ABI and VC++ as well as Windows DLLs don't maintain that invariant.
> +// As a result, enabling SSE2 on 32-bit MinGW is dangerous when not
> +// simultaneously enabling "-mstackrealign".
> +//
> +// See https://github.com/nothings/stb/issues/81 for more information.
> +//
> +// So default to no SSE2 on 32-bit MinGW. If you've read this far and added
> +// -mstackrealign to your build settings, feel free to #define STBI_MINGW_ENABLE_SSE2.
> +#define STBI_NO_SIMD
> +#endif
> +
> +#if !defined(STBI_NO_SIMD) && (defined(STBI__X86_TARGET) || defined(STBI__X64_TARGET))
> +#define STBI_SSE2
> +#include <emmintrin.h>
> +
> +#ifdef _MSC_VER
> +
> +#if _MSC_VER >= 1400 // not VC6
> +#include <intrin.h> // __cpuid
> +static int stbi__cpuid3(void)
> +{
> + int info[4];
> + __cpuid(info,1);
> + return info[3];
> +}
> +#else
> +static int stbi__cpuid3(void)
> +{
> + int res;
> + __asm {
> + mov eax,1
> + cpuid
> + mov res,edx
> + }
> + return res;
> +}
> +#endif
> +
> +#define STBI_SIMD_ALIGN(type, name) __declspec(align(16)) type name
> +
> +#if !defined(STBI_NO_JPEG) && defined(STBI_SSE2)
> +static int stbi__sse2_available(void)
> +{
> + int info3 = stbi__cpuid3();
> + return ((info3 >> 26) & 1) != 0;
> +}
> +#endif
> +
> +#else // assume GCC-style if not VC++
> +#define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16)))
> +
> +#if !defined(STBI_NO_JPEG) && defined(STBI_SSE2)
> +static int stbi__sse2_available(void)
> +{
> + // If we're even attempting to compile this on GCC/Clang, that means
> + // -msse2 is on, which means the compiler is allowed to use SSE2
> + // instructions at will, and so are we.
> + return 1;
> +}
> +#endif
> +
> +#endif
> +#endif
> +
> +// ARM NEON
> +#if defined(STBI_NO_SIMD) && defined(STBI_NEON)
> +#undef STBI_NEON
> +#endif
> +
> +#ifdef STBI_NEON
> +#include <arm_neon.h>
> +// assume GCC or Clang on ARM targets
> +#define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16)))
> +#endif
> +
> +#ifndef STBI_SIMD_ALIGN
> +#define STBI_SIMD_ALIGN(type, name) type name
> +#endif
> +
> +#ifndef STBI_MAX_DIMENSIONS
> +#define STBI_MAX_DIMENSIONS (1 << 24)
> +#endif
> +
> +///////////////////////////////////////////////
> +//
> +// stbi__context struct and start_xxx functions
> +
> +// stbi__context structure is our basic context used by all images, so it
> +// contains all the IO context, plus some basic image information
> +typedef struct
> +{
> + stbi__uint32 img_x, img_y;
> + int img_n, img_out_n;
> +
> + stbi_io_callbacks io;
> + void *io_user_data;
> +
> + int read_from_callbacks;
> + int buflen;
> + stbi_uc buffer_start[128];
> + int callback_already_read;
> +
> + stbi_uc *img_buffer, *img_buffer_end;
> + stbi_uc *img_buffer_original, *img_buffer_original_end;
> +} stbi__context;
> +
> +
> +static void stbi__refill_buffer(stbi__context *s);
> +
> +// initialize a memory-decode context
> +static void stbi__start_mem(stbi__context *s, stbi_uc const *buffer, int len)
> +{
> + s->io.read = NULL;
> + s->read_from_callbacks = 0;
> + s->callback_already_read = 0;
> + s->img_buffer = s->img_buffer_original = (stbi_uc *) buffer;
> + s->img_buffer_end = s->img_buffer_original_end = (stbi_uc *) buffer+len;
> +}
> +
> +// initialize a callback-based context
> +static void stbi__start_callbacks(stbi__context *s, stbi_io_callbacks *c, void *user)
> +{
> + s->io = *c;
> + s->io_user_data = user;
> + s->buflen = sizeof(s->buffer_start);
> + s->read_from_callbacks = 1;
> + s->callback_already_read = 0;
> + s->img_buffer = s->img_buffer_original = s->buffer_start;
> + stbi__refill_buffer(s);
> + s->img_buffer_original_end = s->img_buffer_end;
> +}
> +
> +#ifndef STBI_NO_STDIO
> +
> +static int stbi__stdio_read(void *user, char *data, int size)
> +{
> + return (int) fread(data,1,size,(FILE*) user);
> +}
> +
> +static void stbi__stdio_skip(void *user, int n)
> +{
> + int ch;
> + fseek((FILE*) user, n, SEEK_CUR);
> + ch = fgetc((FILE*) user); /* have to read a byte to reset feof()'s flag */
> + if (ch != EOF) {
> + ungetc(ch, (FILE *) user); /* push byte back onto stream if valid. */
> + }
> +}
> +
> +static int stbi__stdio_eof(void *user)
> +{
> + return feof((FILE*) user) || ferror((FILE *) user);
> +}
> +
> +static stbi_io_callbacks stbi__stdio_callbacks =
> +{
> + stbi__stdio_read,
> + stbi__stdio_skip,
> + stbi__stdio_eof,
> +};
> +
> +static void stbi__start_file(stbi__context *s, FILE *f)
> +{
> + stbi__start_callbacks(s, &stbi__stdio_callbacks, (void *) f);
> +}
> +
> +//static void stop_file(stbi__context *s) { }
> +
> +#endif // !STBI_NO_STDIO
> +
> +static void stbi__rewind(stbi__context *s)
> +{
> + // conceptually rewind SHOULD rewind to the beginning of the stream,
> + // but we just rewind to the beginning of the initial buffer, because
> + // we only use it after doing 'test', which only ever looks at at most 92 bytes
> + s->img_buffer = s->img_buffer_original;
> + s->img_buffer_end = s->img_buffer_original_end;
> +}
> +
> +enum
> +{
> + STBI_ORDER_RGB,
> + STBI_ORDER_BGR
> +};
> +
> +typedef struct
> +{
> + int bits_per_channel;
> + int num_channels;
> + int channel_order;
> +} stbi__result_info;
> +
> +#ifndef STBI_NO_JPEG
> +static int stbi__jpeg_test(stbi__context *s);
> +static void *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
> +static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp);
> +#endif
> +
> +#ifndef STBI_NO_PNG
> +static int stbi__png_test(stbi__context *s);
> +static void *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
> +static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp);
> +static int stbi__png_is16(stbi__context *s);
> +#endif
> +
> +#ifndef STBI_NO_BMP
> +static int stbi__bmp_test(stbi__context *s);
> +static void *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
> +static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp);
> +#endif
> +
> +#ifndef STBI_NO_TGA
> +static int stbi__tga_test(stbi__context *s);
> +static void *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
> +static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp);
> +#endif
> +
> +#ifndef STBI_NO_PSD
> +static int stbi__psd_test(stbi__context *s);
> +static void *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc);
> +static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp);
> +static int stbi__psd_is16(stbi__context *s);
> +#endif
> +
> +#ifndef STBI_NO_HDR
> +static int stbi__hdr_test(stbi__context *s);
> +static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
> +static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp);
> +#endif
> +
> +#ifndef STBI_NO_PIC
> +static int stbi__pic_test(stbi__context *s);
> +static void *stbi__pic_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
> +static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp);
> +#endif
> +
> +#ifndef STBI_NO_GIF
> +static int stbi__gif_test(stbi__context *s);
> +static void *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
> +static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y, int *z, int *comp, int req_comp);
> +static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp);
> +#endif
> +
> +#ifndef STBI_NO_PNM
> +static int stbi__pnm_test(stbi__context *s);
> +static void *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
> +static int stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp);
> +#endif
> +
> +static
> +#ifdef STBI_THREAD_LOCAL
> +STBI_THREAD_LOCAL
> +#endif
> +const char *stbi__g_failure_reason;
> +
> +STBIDEF const char *stbi_failure_reason(void)
> +{
> + return stbi__g_failure_reason;
> +}
> +
> +#ifndef STBI_NO_FAILURE_STRINGS
> +static int stbi__err(const char *str)
> +{
> + stbi__g_failure_reason = str;
> + return 0;
> +}
> +#endif
> +
> +static void *stbi__malloc(size_t size)
> +{
> + return STBI_MALLOC(size);
> +}
> +
> +// stb_image uses ints pervasively, including for offset calculations.
> +// therefore the largest decoded image size we can support with the
> +// current code, even on 64-bit targets, is INT_MAX. this is not a
> +// significant limitation for the intended use case.
> +//
> +// we do, however, need to make sure our size calculations don't
> +// overflow. hence a few helper functions for size calculations that
> +// multiply integers together, making sure that they're non-negative
> +// and no overflow occurs.
> +
> +// return 1 if the sum is valid, 0 on overflow.
> +// negative terms are considered invalid.
> +static int stbi__addsizes_valid(int a, int b)
> +{
> + if (b < 0) return 0;
> + // now 0 <= b <= INT_MAX, hence also
> + // 0 <= INT_MAX - b <= INTMAX.
> + // And "a + b <= INT_MAX" (which might overflow) is the
> + // same as a <= INT_MAX - b (no overflow)
> + return a <= INT_MAX - b;
> +}
> +
> +// returns 1 if the product is valid, 0 on overflow.
> +// negative factors are considered invalid.
> +static int stbi__mul2sizes_valid(int a, int b)
> +{
> + if (a < 0 || b < 0) return 0;
> + if (b == 0) return 1; // mul-by-0 is always safe
> + // portable way to check for no overflows in a*b
> + return a <= INT_MAX/b;
> +}
> +
> +#if !defined(STBI_NO_JPEG) || !defined(STBI_NO_PNG) || !defined(STBI_NO_TGA) || !defined(STBI_NO_HDR)
> +// returns 1 if "a*b + add" has no negative terms/factors and doesn't overflow
> +static int stbi__mad2sizes_valid(int a, int b, int add)
> +{
> + return stbi__mul2sizes_valid(a, b) && stbi__addsizes_valid(a*b, add);
> +}
> +#endif
> +
> +// returns 1 if "a*b*c + add" has no negative terms/factors and doesn't overflow
> +static int stbi__mad3sizes_valid(int a, int b, int c, int add)
> +{
> + return stbi__mul2sizes_valid(a, b) && stbi__mul2sizes_valid(a*b, c) &&
> + stbi__addsizes_valid(a*b*c, add);
> +}
> +
> +// returns 1 if "a*b*c*d + add" has no negative terms/factors and doesn't overflow
> +#if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR)
> +static int stbi__mad4sizes_valid(int a, int b, int c, int d, int add)
> +{
> + return stbi__mul2sizes_valid(a, b) && stbi__mul2sizes_valid(a*b, c) &&
> + stbi__mul2sizes_valid(a*b*c, d) && stbi__addsizes_valid(a*b*c*d, add);
> +}
> +#endif
> +
> +#if !defined(STBI_NO_JPEG) || !defined(STBI_NO_PNG) || !defined(STBI_NO_TGA) || !defined(STBI_NO_HDR)
> +// mallocs with size overflow checking
> +static void *stbi__malloc_mad2(int a, int b, int add)
> +{
> + if (!stbi__mad2sizes_valid(a, b, add)) return NULL;
> + return stbi__malloc(a*b + add);
> +}
> +#endif
> +
> +static void *stbi__malloc_mad3(int a, int b, int c, int add)
> +{
> + if (!stbi__mad3sizes_valid(a, b, c, add)) return NULL;
> + return stbi__malloc(a*b*c + add);
> +}
> +
> +#if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR)
> +static void *stbi__malloc_mad4(int a, int b, int c, int d, int add)
> +{
> + if (!stbi__mad4sizes_valid(a, b, c, d, add)) return NULL;
> + return stbi__malloc(a*b*c*d + add);
> +}
> +#endif
> +
> +// stbi__err - error
> +// stbi__errpf - error returning pointer to float
> +// stbi__errpuc - error returning pointer to unsigned char
> +
> +#ifdef STBI_NO_FAILURE_STRINGS
> + #define stbi__err(x,y) 0
> +#elif defined(STBI_FAILURE_USERMSG)
> + #define stbi__err(x,y) stbi__err(y)
> +#else
> + #define stbi__err(x,y) stbi__err(x)
> +#endif
> +
> +#define stbi__errpf(x,y) ((float *)(size_t) (stbi__err(x,y)?NULL:NULL))
> +#define stbi__errpuc(x,y) ((unsigned char *)(size_t) (stbi__err(x,y)?NULL:NULL))
> +
> +STBIDEF void stbi_image_free(void *retval_from_stbi_load)
> +{
> + STBI_FREE(retval_from_stbi_load);
> +}
> +
> +#ifndef STBI_NO_LINEAR
> +static float *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp);
> +#endif
> +
> +#ifndef STBI_NO_HDR
> +static stbi_uc *stbi__hdr_to_ldr(float *data, int x, int y, int comp);
> +#endif
> +
> +static int stbi__vertically_flip_on_load_global = 0;
> +
> +STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip)
> +{
> + stbi__vertically_flip_on_load_global = flag_true_if_should_flip;
> +}
> +
> +#ifndef STBI_THREAD_LOCAL
> +#define stbi__vertically_flip_on_load stbi__vertically_flip_on_load_global
> +#else
> +static STBI_THREAD_LOCAL int stbi__vertically_flip_on_load_local, stbi__vertically_flip_on_load_set;
> +
> +STBIDEF void stbi_set_flip_vertically_on_load_thread(int flag_true_if_should_flip)
> +{
> + stbi__vertically_flip_on_load_local = flag_true_if_should_flip;
> + stbi__vertically_flip_on_load_set = 1;
> +}
> +
> +#define stbi__vertically_flip_on_load (stbi__vertically_flip_on_load_set \
> + ? stbi__vertically_flip_on_load_local \
> + : stbi__vertically_flip_on_load_global)
> +#endif // STBI_THREAD_LOCAL
> +
> +static void *stbi__load_main(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc)
> +{
> + memset(ri, 0, sizeof(*ri)); // make sure it's initialized if we add new fields
> + ri->bits_per_channel = 8; // default is 8 so most paths don't have to be changed
> + ri->channel_order = STBI_ORDER_RGB; // all current input & output are this, but this is here so we can add BGR order
> + ri->num_channels = 0;
> +
> + #ifndef STBI_NO_JPEG
> + if (stbi__jpeg_test(s)) return stbi__jpeg_load(s,x,y,comp,req_comp, ri);
> + #endif
> + #ifndef STBI_NO_PNG
> + if (stbi__png_test(s)) return stbi__png_load(s,x,y,comp,req_comp, ri);
> + #endif
> + #ifndef STBI_NO_BMP
> + if (stbi__bmp_test(s)) return stbi__bmp_load(s,x,y,comp,req_comp, ri);
> + #endif
> + #ifndef STBI_NO_GIF
> + if (stbi__gif_test(s)) return stbi__gif_load(s,x,y,comp,req_comp, ri);
> + #endif
> + #ifndef STBI_NO_PSD
> + if (stbi__psd_test(s)) return stbi__psd_load(s,x,y,comp,req_comp, ri, bpc);
> + #else
> + STBI_NOTUSED(bpc);
> + #endif
> + #ifndef STBI_NO_PIC
> + if (stbi__pic_test(s)) return stbi__pic_load(s,x,y,comp,req_comp, ri);
> + #endif
> + #ifndef STBI_NO_PNM
> + if (stbi__pnm_test(s)) return stbi__pnm_load(s,x,y,comp,req_comp, ri);
> + #endif
> +
> + #ifndef STBI_NO_HDR
> + if (stbi__hdr_test(s)) {
> + float *hdr = stbi__hdr_load(s, x,y,comp,req_comp, ri);
> + return stbi__hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp);
> + }
> + #endif
> +
> + #ifndef STBI_NO_TGA
> + // test tga last because it's a crappy test!
> + if (stbi__tga_test(s))
> + return stbi__tga_load(s,x,y,comp,req_comp, ri);
> + #endif
> +
> + return stbi__errpuc("unknown image type", "Image not of any known type, or corrupt");
> +}
> +
> +static stbi_uc *stbi__convert_16_to_8(stbi__uint16 *orig, int w, int h, int channels)
> +{
> + int i;
> + int img_len = w * h * channels;
> + stbi_uc *reduced;
> +
> + reduced = (stbi_uc *) stbi__malloc(img_len);
> + if (reduced == NULL) return stbi__errpuc("outofmem", "Out of memory");
> +
> + for (i = 0; i < img_len; ++i)
> + reduced[i] = (stbi_uc)((orig[i] >> 8) & 0xFF); // top half of each byte is sufficient approx of 16->8 bit scaling
> +
> + STBI_FREE(orig);
> + return reduced;
> +}
> +
> +static stbi__uint16 *stbi__convert_8_to_16(stbi_uc *orig, int w, int h, int channels)
> +{
> + int i;
> + int img_len = w * h * channels;
> + stbi__uint16 *enlarged;
> +
> + enlarged = (stbi__uint16 *) stbi__malloc(img_len*2);
> + if (enlarged == NULL) return (stbi__uint16 *) stbi__errpuc("outofmem", "Out of memory");
> +
> + for (i = 0; i < img_len; ++i)
> + enlarged[i] = (stbi__uint16)((orig[i] << 8) + orig[i]); // replicate to high and low byte, maps 0->0, 255->0xffff
> +
> + STBI_FREE(orig);
> + return enlarged;
> +}
> +
> +static void stbi__vertical_flip(void *image, int w, int h, int bytes_per_pixel)
> +{
> + int row;
> + size_t bytes_per_row = (size_t)w * bytes_per_pixel;
> + stbi_uc temp[2048];
> + stbi_uc *bytes = (stbi_uc *)image;
> +
> + for (row = 0; row < (h>>1); row++) {
> + stbi_uc *row0 = bytes + row*bytes_per_row;
> + stbi_uc *row1 = bytes + (h - row - 1)*bytes_per_row;
> + // swap row0 with row1
> + size_t bytes_left = bytes_per_row;
> + while (bytes_left) {
> + size_t bytes_copy = (bytes_left < sizeof(temp)) ? bytes_left : sizeof(temp);
> + memcpy(temp, row0, bytes_copy);
> + memcpy(row0, row1, bytes_copy);
> + memcpy(row1, temp, bytes_copy);
> + row0 += bytes_copy;
> + row1 += bytes_copy;
> + bytes_left -= bytes_copy;
> + }
> + }
> +}
> +
> +#ifndef STBI_NO_GIF
> +static void stbi__vertical_flip_slices(void *image, int w, int h, int z, int bytes_per_pixel)
> +{
> + int slice;
> + int slice_size = w * h * bytes_per_pixel;
> +
> + stbi_uc *bytes = (stbi_uc *)image;
> + for (slice = 0; slice < z; ++slice) {
> + stbi__vertical_flip(bytes, w, h, bytes_per_pixel);
> + bytes += slice_size;
> + }
> +}
> +#endif
> +
> +static unsigned char *stbi__load_and_postprocess_8bit(stbi__context *s, int *x, int *y, int *comp, int req_comp)
> +{
> + stbi__result_info ri;
> + void *result = stbi__load_main(s, x, y, comp, req_comp, &ri, 8);
> +
> + if (result == NULL)
> + return NULL;
> +
> + // it is the responsibility of the loaders to make sure we get either 8 or 16 bit.
> + STBI_ASSERT(ri.bits_per_channel == 8 || ri.bits_per_channel == 16);
> +
> + if (ri.bits_per_channel != 8) {
> + result = stbi__convert_16_to_8((stbi__uint16 *) result, *x, *y, req_comp == 0 ? *comp : req_comp);
> + ri.bits_per_channel = 8;
> + }
> +
> + // @TODO: move stbi__convert_format to here
> +
> + if (stbi__vertically_flip_on_load) {
> + int channels = req_comp ? req_comp : *comp;
> + stbi__vertical_flip(result, *x, *y, channels * sizeof(stbi_uc));
> + }
> +
> + return (unsigned char *) result;
> +}
> +
> +static stbi__uint16 *stbi__load_and_postprocess_16bit(stbi__context *s, int *x, int *y, int *comp, int req_comp)
> +{
> + stbi__result_info ri;
> + void *result = stbi__load_main(s, x, y, comp, req_comp, &ri, 16);
> +
> + if (result == NULL)
> + return NULL;
> +
> + // it is the responsibility of the loaders to make sure we get either 8 or 16 bit.
> + STBI_ASSERT(ri.bits_per_channel == 8 || ri.bits_per_channel == 16);
> +
> + if (ri.bits_per_channel != 16) {
> + result = stbi__convert_8_to_16((stbi_uc *) result, *x, *y, req_comp == 0 ? *comp : req_comp);
> + ri.bits_per_channel = 16;
> + }
> +
> + // @TODO: move stbi__convert_format16 to here
> + // @TODO: special case RGB-to-Y (and RGBA-to-YA) for 8-bit-to-16-bit case to keep more precision
> +
> + if (stbi__vertically_flip_on_load) {
> + int channels = req_comp ? req_comp : *comp;
> + stbi__vertical_flip(result, *x, *y, channels * sizeof(stbi__uint16));
> + }
> +
> + return (stbi__uint16 *) result;
> +}
> +
> +#if !defined(STBI_NO_HDR) && !defined(STBI_NO_LINEAR)
> +static void stbi__float_postprocess(float *result, int *x, int *y, int *comp, int req_comp)
> +{
> + if (stbi__vertically_flip_on_load && result != NULL) {
> + int channels = req_comp ? req_comp : *comp;
> + stbi__vertical_flip(result, *x, *y, channels * sizeof(float));
> + }
> +}
> +#endif
> +
> +#ifndef STBI_NO_STDIO
> +
> +#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
> +STBI_EXTERN __declspec(dllimport) int __stdcall MultiByteToWideChar(unsigned int cp, unsigned long flags, const char *str, int cbmb, wchar_t *widestr, int cchwide);
> +STBI_EXTERN __declspec(dllimport) int __stdcall WideCharToMultiByte(unsigned int cp, unsigned long flags, const wchar_t *widestr, int cchwide, char *str, int cbmb, const char *defchar, int *used_default);
> +#endif
> +
> +#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
> +STBIDEF int stbi_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input)
> +{
> + return WideCharToMultiByte(65001 /* UTF8 */, 0, input, -1, buffer, (int) bufferlen, NULL, NULL);
> +}
> +#endif
> +
> +static FILE *stbi__fopen(char const *filename, char const *mode)
> +{
> + FILE *f;
> +#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
> + wchar_t wMode[64];
> + wchar_t wFilename[1024];
> + if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)))
> + return 0;
> +
> + if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)))
> + return 0;
> +
> +#if _MSC_VER >= 1400
> + if (0 != _wfopen_s(&f, wFilename, wMode))
> + f = 0;
> +#else
> + f = _wfopen(wFilename, wMode);
> +#endif
> +
> +#elif defined(_MSC_VER) && _MSC_VER >= 1400
> + if (0 != fopen_s(&f, filename, mode))
> + f=0;
> +#else
> + f = fopen(filename, mode);
> +#endif
> + return f;
> +}
> +
> +
> +STBIDEF stbi_uc *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp)
> +{
> + FILE *f = stbi__fopen(filename, "rb");
> + unsigned char *result;
> + if (!f) return stbi__errpuc("can't fopen", "Unable to open file");
> + result = stbi_load_from_file(f,x,y,comp,req_comp);
> + fclose(f);
> + return result;
> +}
> +
> +STBIDEF stbi_uc *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
> +{
> + unsigned char *result;
> + stbi__context s;
> + stbi__start_file(&s,f);
> + result = stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp);
> + if (result) {
> + // need to 'unget' all the characters in the IO buffer
> + fseek(f, - (int) (s.img_buffer_end - s.img_buffer), SEEK_CUR);
> + }
> + return result;
> +}
> +
> +STBIDEF stbi__uint16 *stbi_load_from_file_16(FILE *f, int *x, int *y, int *comp, int req_comp)
> +{
> + stbi__uint16 *result;
> + stbi__context s;
> + stbi__start_file(&s,f);
> + result = stbi__load_and_postprocess_16bit(&s,x,y,comp,req_comp);
> + if (result) {
> + // need to 'unget' all the characters in the IO buffer
> + fseek(f, - (int) (s.img_buffer_end - s.img_buffer), SEEK_CUR);
> + }
> + return result;
> +}
> +
> +STBIDEF stbi_us *stbi_load_16(char const *filename, int *x, int *y, int *comp, int req_comp)
> +{
> + FILE *f = stbi__fopen(filename, "rb");
> + stbi__uint16 *result;
> + if (!f) return (stbi_us *) stbi__errpuc("can't fopen", "Unable to open file");
> + result = stbi_load_from_file_16(f,x,y,comp,req_comp);
> + fclose(f);
> + return result;
> +}
> +
> +
> +#endif //!STBI_NO_STDIO
> +
> +STBIDEF stbi_us *stbi_load_16_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels)
> +{
> + stbi__context s;
> + stbi__start_mem(&s,buffer,len);
> + return stbi__load_and_postprocess_16bit(&s,x,y,channels_in_file,desired_channels);
> +}
> +
> +STBIDEF stbi_us *stbi_load_16_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *channels_in_file, int desired_channels)
> +{
> + stbi__context s;
> + stbi__start_callbacks(&s, (stbi_io_callbacks *)clbk, user);
> + return stbi__load_and_postprocess_16bit(&s,x,y,channels_in_file,desired_channels);
> +}
> +
> +STBIDEF stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
> +{
> + stbi__context s;
> + stbi__start_mem(&s,buffer,len);
> + return stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp);
> +}
> +
> +STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp)
> +{
> + stbi__context s;
> + stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
> + return stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp);
> +}
> +
> +#ifndef STBI_NO_GIF
> +STBIDEF stbi_uc *stbi_load_gif_from_memory(stbi_uc const *buffer, int len, int **delays, int *x, int *y, int *z, int *comp, int req_comp)
> +{
> + unsigned char *result;
> + stbi__context s;
> + stbi__start_mem(&s,buffer,len);
> +
> + result = (unsigned char*) stbi__load_gif_main(&s, delays, x, y, z, comp, req_comp);
> + if (stbi__vertically_flip_on_load) {
> + stbi__vertical_flip_slices( result, *x, *y, *z, *comp );
> + }
> +
> + return result;
> +}
> +#endif
> +
> +#ifndef STBI_NO_LINEAR
> +static float *stbi__loadf_main(stbi__context *s, int *x, int *y, int *comp, int req_comp)
> +{
> + unsigned char *data;
> + #ifndef STBI_NO_HDR
> + if (stbi__hdr_test(s)) {
> + stbi__result_info ri;
> + float *hdr_data = stbi__hdr_load(s,x,y,comp,req_comp, &ri);
> + if (hdr_data)
> + stbi__float_postprocess(hdr_data,x,y,comp,req_comp);
> + return hdr_data;
> + }
> + #endif
> + data = stbi__load_and_postprocess_8bit(s, x, y, comp, req_comp);
> + if (data)
> + return stbi__ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp);
> + return stbi__errpf("unknown image type", "Image not of any known type, or corrupt");
> +}
> +
> +STBIDEF float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
> +{
> + stbi__context s;
> + stbi__start_mem(&s,buffer,len);
> + return stbi__loadf_main(&s,x,y,comp,req_comp);
> +}
> +
> +STBIDEF float *stbi_loadf_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp)
> +{
> + stbi__context s;
> + stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
> + return stbi__loadf_main(&s,x,y,comp,req_comp);
> +}
> +
> +#ifndef STBI_NO_STDIO
> +STBIDEF float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp)
> +{
> + float *result;
> + FILE *f = stbi__fopen(filename, "rb");
> + if (!f) return stbi__errpf("can't fopen", "Unable to open file");
> + result = stbi_loadf_from_file(f,x,y,comp,req_comp);
> + fclose(f);
> + return result;
> +}
> +
> +STBIDEF float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
> +{
> + stbi__context s;
> + stbi__start_file(&s,f);
> + return stbi__loadf_main(&s,x,y,comp,req_comp);
> +}
> +#endif // !STBI_NO_STDIO
> +
> +#endif // !STBI_NO_LINEAR
> +
> +// these is-hdr-or-not is defined independent of whether STBI_NO_LINEAR is
> +// defined, for API simplicity; if STBI_NO_LINEAR is defined, it always
> +// reports false!
> +
> +STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len)
> +{
> + #ifndef STBI_NO_HDR
> + stbi__context s;
> + stbi__start_mem(&s,buffer,len);
> + return stbi__hdr_test(&s);
> + #else
> + STBI_NOTUSED(buffer);
> + STBI_NOTUSED(len);
> + return 0;
> + #endif
> +}
> +
> +#ifndef STBI_NO_STDIO
> +STBIDEF int stbi_is_hdr (char const *filename)
> +{
> + FILE *f = stbi__fopen(filename, "rb");
> + int result=0;
> + if (f) {
> + result = stbi_is_hdr_from_file(f);
> + fclose(f);
> + }
> + return result;
> +}
> +
> +STBIDEF int stbi_is_hdr_from_file(FILE *f)
> +{
> + #ifndef STBI_NO_HDR
> + long pos = ftell(f);
> + int res;
> + stbi__context s;
> + stbi__start_file(&s,f);
> + res = stbi__hdr_test(&s);
> + fseek(f, pos, SEEK_SET);
> + return res;
> + #else
> + STBI_NOTUSED(f);
> + return 0;
> + #endif
> +}
> +#endif // !STBI_NO_STDIO
> +
> +STBIDEF int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user)
> +{
> + #ifndef STBI_NO_HDR
> + stbi__context s;
> + stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
> + return stbi__hdr_test(&s);
> + #else
> + STBI_NOTUSED(clbk);
> + STBI_NOTUSED(user);
> + return 0;
> + #endif
> +}
> +
> +#ifndef STBI_NO_LINEAR
> +static float stbi__l2h_gamma=2.2f, stbi__l2h_scale=1.0f;
> +
> +STBIDEF void stbi_ldr_to_hdr_gamma(float gamma) { stbi__l2h_gamma = gamma; }
> +STBIDEF void stbi_ldr_to_hdr_scale(float scale) { stbi__l2h_scale = scale; }
> +#endif
> +
> +static float stbi__h2l_gamma_i=1.0f/2.2f, stbi__h2l_scale_i=1.0f;
> +
> +STBIDEF void stbi_hdr_to_ldr_gamma(float gamma) { stbi__h2l_gamma_i = 1/gamma; }
> +STBIDEF void stbi_hdr_to_ldr_scale(float scale) { stbi__h2l_scale_i = 1/scale; }
> +
> +
> +//////////////////////////////////////////////////////////////////////////////
> +//
> +// Common code used by all image loaders
> +//
> +
> +enum
> +{
> + STBI__SCAN_load=0,
> + STBI__SCAN_type,
> + STBI__SCAN_header
> +};
> +
> +static void stbi__refill_buffer(stbi__context *s)
> +{
> + int n = (s->io.read)(s->io_user_data,(char*)s->buffer_start,s->buflen);
> + s->callback_already_read += (int) (s->img_buffer - s->img_buffer_original);
> + if (n == 0) {
> + // at end of file, treat same as if from memory, but need to handle case
> + // where s->img_buffer isn't pointing to safe memory, e.g. 0-byte file
> + s->read_from_callbacks = 0;
> + s->img_buffer = s->buffer_start;
> + s->img_buffer_end = s->buffer_start+1;
> + *s->img_buffer = 0;
> + } else {
> + s->img_buffer = s->buffer_start;
> + s->img_buffer_end = s->buffer_start + n;
> + }
> +}
> +
> +stbi_inline static stbi_uc stbi__get8(stbi__context *s)
> +{
> + if (s->img_buffer < s->img_buffer_end)
> + return *s->img_buffer++;
> + if (s->read_from_callbacks) {
> + stbi__refill_buffer(s);
> + return *s->img_buffer++;
> + }
> + return 0;
> +}
> +
> +#if defined(STBI_NO_JPEG) && defined(STBI_NO_HDR) && defined(STBI_NO_PIC) && defined(STBI_NO_PNM)
> +// nothing
> +#else
> +stbi_inline static int stbi__at_eof(stbi__context *s)
> +{
> + if (s->io.read) {
> + if (!(s->io.eof)(s->io_user_data)) return 0;
> + // if feof() is true, check if buffer = end
> + // special case: we've only got the special 0 character at the end
> + if (s->read_from_callbacks == 0) return 1;
> + }
> +
> + return s->img_buffer >= s->img_buffer_end;
> +}
> +#endif
> +
> +#if defined(STBI_NO_JPEG) && defined(STBI_NO_PNG) && defined(STBI_NO_BMP) && defined(STBI_NO_PSD) && defined(STBI_NO_TGA) && defined(STBI_NO_GIF) && defined(STBI_NO_PIC)
> +// nothing
> +#else
> +static void stbi__skip(stbi__context *s, int n)
> +{
> + if (n == 0) return; // already there!
> + if (n < 0) {
> + s->img_buffer = s->img_buffer_end;
> + return;
> + }
> + if (s->io.read) {
> + int blen = (int) (s->img_buffer_end - s->img_buffer);
> + if (blen < n) {
> + s->img_buffer = s->img_buffer_end;
> + (s->io.skip)(s->io_user_data, n - blen);
> + return;
> + }
> + }
> + s->img_buffer += n;
> +}
> +#endif
> +
> +#if defined(STBI_NO_PNG) && defined(STBI_NO_TGA) && defined(STBI_NO_HDR) && defined(STBI_NO_PNM)
> +// nothing
> +#else
> +static int stbi__getn(stbi__context *s, stbi_uc *buffer, int n)
> +{
> + if (s->io.read) {
> + int blen = (int) (s->img_buffer_end - s->img_buffer);
> + if (blen < n) {
> + int res, count;
> +
> + memcpy(buffer, s->img_buffer, blen);
> +
> + count = (s->io.read)(s->io_user_data, (char*) buffer + blen, n - blen);
> + res = (count == (n-blen));
> + s->img_buffer = s->img_buffer_end;
> + return res;
> + }
> + }
> +
> + if (s->img_buffer+n <= s->img_buffer_end) {
> + memcpy(buffer, s->img_buffer, n);
> + s->img_buffer += n;
> + return 1;
> + } else
> + return 0;
> +}
> +#endif
> +
> +#if defined(STBI_NO_JPEG) && defined(STBI_NO_PNG) && defined(STBI_NO_PSD) && defined(STBI_NO_PIC)
> +// nothing
> +#else
> +static int stbi__get16be(stbi__context *s)
> +{
> + int z = stbi__get8(s);
> + return (z << 8) + stbi__get8(s);
> +}
> +#endif
> +
> +#if defined(STBI_NO_PNG) && defined(STBI_NO_PSD) && defined(STBI_NO_PIC)
> +// nothing
> +#else
> +static stbi__uint32 stbi__get32be(stbi__context *s)
> +{
> + stbi__uint32 z = stbi__get16be(s);
> + return (z << 16) + stbi__get16be(s);
> +}
> +#endif
> +
> +#if defined(STBI_NO_BMP) && defined(STBI_NO_TGA) && defined(STBI_NO_GIF)
> +// nothing
> +#else
> +static int stbi__get16le(stbi__context *s)
> +{
> + int z = stbi__get8(s);
> + return z + (stbi__get8(s) << 8);
> +}
> +#endif
> +
> +#ifndef STBI_NO_BMP
> +static stbi__uint32 stbi__get32le(stbi__context *s)
> +{
> + stbi__uint32 z = stbi__get16le(s);
> + return z + (stbi__get16le(s) << 16);
> +}
> +#endif
> +
> +#define STBI__BYTECAST(x) ((stbi_uc) ((x) & 255)) // truncate int to byte without warnings
> +
> +#if defined(STBI_NO_JPEG) && defined(STBI_NO_PNG) && defined(STBI_NO_BMP) && defined(STBI_NO_PSD) && defined(STBI_NO_TGA) && defined(STBI_NO_GIF) && defined(STBI_NO_PIC) && defined(STBI_NO_PNM)
> +// nothing
> +#else
> +//////////////////////////////////////////////////////////////////////////////
> +//
> +// generic converter from built-in img_n to req_comp
> +// individual types do this automatically as much as possible (e.g. jpeg
> +// does all cases internally since it needs to colorspace convert anyway,
> +// and it never has alpha, so very few cases ). png can automatically
> +// interleave an alpha=255 channel, but falls back to this for other cases
> +//
> +// assume data buffer is malloced, so malloc a new one and free that one
> +// only failure mode is malloc failing
> +
> +static stbi_uc stbi__compute_y(int r, int g, int b)
> +{
> + return (stbi_uc) (((r*77) + (g*150) + (29*b)) >> 8);
> +}
> +#endif
> +
> +#if defined(STBI_NO_PNG) && defined(STBI_NO_BMP) && defined(STBI_NO_PSD) && defined(STBI_NO_TGA) && defined(STBI_NO_GIF) && defined(STBI_NO_PIC) && defined(STBI_NO_PNM)
> +// nothing
> +#else
> +static unsigned char *stbi__convert_format(unsigned char *data, int img_n, int req_comp, unsigned int x, unsigned int y)
> +{
> + int i,j;
> + unsigned char *good;
> +
> + if (req_comp == img_n) return data;
> + STBI_ASSERT(req_comp >= 1 && req_comp <= 4);
> +
> + good = (unsigned char *) stbi__malloc_mad3(req_comp, x, y, 0);
> + if (good == NULL) {
> + STBI_FREE(data);
> + return stbi__errpuc("outofmem", "Out of memory");
> + }
> +
> + for (j=0; j < (int) y; ++j) {
> + unsigned char *src = data + j * x * img_n ;
> + unsigned char *dest = good + j * x * req_comp;
> +
> + #define STBI__COMBO(a,b) ((a)*8+(b))
> + #define STBI__CASE(a,b) case STBI__COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
> + // convert source image with img_n components to one with req_comp components;
> + // avoid switch per pixel, so use switch per scanline and massive macros
> + switch (STBI__COMBO(img_n, req_comp)) {
> + STBI__CASE(1,2) { dest[0]=src[0]; dest[1]=255; } break;
> + STBI__CASE(1,3) { dest[0]=dest[1]=dest[2]=src[0]; } break;
> + STBI__CASE(1,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=255; } break;
> + STBI__CASE(2,1) { dest[0]=src[0]; } break;
> + STBI__CASE(2,3) { dest[0]=dest[1]=dest[2]=src[0]; } break;
> + STBI__CASE(2,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=src[1]; } break;
> + STBI__CASE(3,4) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2];dest[3]=255; } break;
> + STBI__CASE(3,1) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); } break;
> + STBI__CASE(3,2) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); dest[1] = 255; } break;
> + STBI__CASE(4,1) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); } break;
> + STBI__CASE(4,2) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); dest[1] = src[3]; } break;
> + STBI__CASE(4,3) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2]; } break;
> + default: STBI_ASSERT(0); STBI_FREE(data); STBI_FREE(good); return stbi__errpuc("unsupported", "Unsupported format conversion");
> + }
> + #undef STBI__CASE
> + }
> +
> + STBI_FREE(data);
> + return good;
> +}
> +#endif
> +
> +#if defined(STBI_NO_PNG) && defined(STBI_NO_PSD)
> +// nothing
> +#else
> +static stbi__uint16 stbi__compute_y_16(int r, int g, int b)
> +{
> + return (stbi__uint16) (((r*77) + (g*150) + (29*b)) >> 8);
> +}
> +#endif
> +
> +#if defined(STBI_NO_PNG) && defined(STBI_NO_PSD)
> +// nothing
> +#else
> +static stbi__uint16 *stbi__convert_format16(stbi__uint16 *data, int img_n, int req_comp, unsigned int x, unsigned int y)
> +{
> + int i,j;
> + stbi__uint16 *good;
> +
> + if (req_comp == img_n) return data;
> + STBI_ASSERT(req_comp >= 1 && req_comp <= 4);
> +
> + good = (stbi__uint16 *) stbi__malloc(req_comp * x * y * 2);
> + if (good == NULL) {
> + STBI_FREE(data);
> + return (stbi__uint16 *) stbi__errpuc("outofmem", "Out of memory");
> + }
> +
> + for (j=0; j < (int) y; ++j) {
> + stbi__uint16 *src = data + j * x * img_n ;
> + stbi__uint16 *dest = good + j * x * req_comp;
> +
> + #define STBI__COMBO(a,b) ((a)*8+(b))
> + #define STBI__CASE(a,b) case STBI__COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
> + // convert source image with img_n components to one with req_comp components;
> + // avoid switch per pixel, so use switch per scanline and massive macros
> + switch (STBI__COMBO(img_n, req_comp)) {
> + STBI__CASE(1,2) { dest[0]=src[0]; dest[1]=0xffff; } break;
> + STBI__CASE(1,3) { dest[0]=dest[1]=dest[2]=src[0]; } break;
> + STBI__CASE(1,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=0xffff; } break;
> + STBI__CASE(2,1) { dest[0]=src[0]; } break;
> + STBI__CASE(2,3) { dest[0]=dest[1]=dest[2]=src[0]; } break;
> + STBI__CASE(2,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=src[1]; } break;
> + STBI__CASE(3,4) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2];dest[3]=0xffff; } break;
> + STBI__CASE(3,1) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); } break;
> + STBI__CASE(3,2) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); dest[1] = 0xffff; } break;
> + STBI__CASE(4,1) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); } break;
> + STBI__CASE(4,2) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); dest[1] = src[3]; } break;
> + STBI__CASE(4,3) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2]; } break;
> + default: STBI_ASSERT(0); STBI_FREE(data); STBI_FREE(good); return (stbi__uint16*) stbi__errpuc("unsupported", "Unsupported format conversion");
> + }
> + #undef STBI__CASE
> + }
> +
> + STBI_FREE(data);
> + return good;
> +}
> +#endif
> +
> +#ifndef STBI_NO_LINEAR
> +static float *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp)
> +{
> + int i,k,n;
> + float *output;
> + if (!data) return NULL;
> + output = (float *) stbi__malloc_mad4(x, y, comp, sizeof(float), 0);
> + if (output == NULL) { STBI_FREE(data); return stbi__errpf("outofmem", "Out of memory"); }
> + // compute number of non-alpha components
> + if (comp & 1) n = comp; else n = comp-1;
> + for (i=0; i < x*y; ++i) {
> + for (k=0; k < n; ++k) {
> + output[i*comp + k] = (float) (pow(data[i*comp+k]/255.0f, stbi__l2h_gamma) * stbi__l2h_scale);
> + }
> + }
> + if (n < comp) {
> + for (i=0; i < x*y; ++i) {
> + output[i*comp + n] = data[i*comp + n]/255.0f;
> + }
> + }
> + STBI_FREE(data);
> + return output;
> +}
> +#endif
> +
> +#ifndef STBI_NO_HDR
> +#define stbi__float2int(x) ((int) (x))
> +static stbi_uc *stbi__hdr_to_ldr(float *data, int x, int y, int comp)
> +{
> + int i,k,n;
> + stbi_uc *output;
> + if (!data) return NULL;
> + output = (stbi_uc *) stbi__malloc_mad3(x, y, comp, 0);
> + if (output == NULL) { STBI_FREE(data); return stbi__errpuc("outofmem", "Out of memory"); }
> + // compute number of non-alpha components
> + if (comp & 1) n = comp; else n = comp-1;
> + for (i=0; i < x*y; ++i) {
> + for (k=0; k < n; ++k) {
> + float z = (float) pow(data[i*comp+k]*stbi__h2l_scale_i, stbi__h2l_gamma_i) * 255 + 0.5f;
> + if (z < 0) z = 0;
> + if (z > 255) z = 255;
> + output[i*comp + k] = (stbi_uc) stbi__float2int(z);
> + }
> + if (k < comp) {
> + float z = data[i*comp+k] * 255 + 0.5f;
> + if (z < 0) z = 0;
> + if (z > 255) z = 255;
> + output[i*comp + k] = (stbi_uc) stbi__float2int(z);
> + }
> + }
> + STBI_FREE(data);
> + return output;
> +}
> +#endif
> +
> +//////////////////////////////////////////////////////////////////////////////
> +//
> +// "baseline" JPEG/JFIF decoder
> +//
> +// simple implementation
> +// - doesn't support delayed output of y-dimension
> +// - simple interface (only one output format: 8-bit interleaved RGB)
> +// - doesn't try to recover corrupt jpegs
> +// - doesn't allow partial loading, loading multiple at once
> +// - still fast on x86 (copying globals into locals doesn't help x86)
> +// - allocates lots of intermediate memory (full size of all components)
> +// - non-interleaved case requires this anyway
> +// - allows good upsampling (see next)
> +// high-quality
> +// - upsampled channels are bilinearly interpolated, even across blocks
> +// - quality integer IDCT derived from IJG's 'slow'
> +// performance
> +// - fast huffman; reasonable integer IDCT
> +// - some SIMD kernels for common paths on targets with SSE2/NEON
> +// - uses a lot of intermediate memory, could cache poorly
> +
> +#ifndef STBI_NO_JPEG
> +
> +// huffman decoding acceleration
> +#define FAST_BITS 9 // larger handles more cases; smaller stomps less cache
> +
> +typedef struct
> +{
> + stbi_uc fast[1 << FAST_BITS];
> + // weirdly, repacking this into AoS is a 10% speed loss, instead of a win
> + stbi__uint16 code[256];
> + stbi_uc values[256];
> + stbi_uc size[257];
> + unsigned int maxcode[18];
> + int delta[17]; // old 'firstsymbol' - old 'firstcode'
> +} stbi__huffman;
> +
> +typedef struct
> +{
> + stbi__context *s;
> + stbi__huffman huff_dc[4];
> + stbi__huffman huff_ac[4];
> + stbi__uint16 dequant[4][64];
> + stbi__int16 fast_ac[4][1 << FAST_BITS];
> +
> +// sizes for components, interleaved MCUs
> + int img_h_max, img_v_max;
> + int img_mcu_x, img_mcu_y;
> + int img_mcu_w, img_mcu_h;
> +
> +// definition of jpeg image component
> + struct
> + {
> + int id;
> + int h,v;
> + int tq;
> + int hd,ha;
> + int dc_pred;
> +
> + int x,y,w2,h2;
> + stbi_uc *data;
> + void *raw_data, *raw_coeff;
> + stbi_uc *linebuf;
> + short *coeff; // progressive only
> + int coeff_w, coeff_h; // number of 8x8 coefficient blocks
> + } img_comp[4];
> +
> + stbi__uint32 code_buffer; // jpeg entropy-coded buffer
> + int code_bits; // number of valid bits
> + unsigned char marker; // marker seen while filling entropy buffer
> + int nomore; // flag if we saw a marker so must stop
> +
> + int progressive;
> + int spec_start;
> + int spec_end;
> + int succ_high;
> + int succ_low;
> + int eob_run;
> + int jfif;
> + int app14_color_transform; // Adobe APP14 tag
> + int rgb;
> +
> + int scan_n, order[4];
> + int restart_interval, todo;
> +
> +// kernels
> + void (*idct_block_kernel)(stbi_uc *out, int out_stride, short data[64]);
> + void (*YCbCr_to_RGB_kernel)(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step);
> + stbi_uc *(*resample_row_hv_2_kernel)(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs);
> +} stbi__jpeg;
> +
> +static int stbi__build_huffman(stbi__huffman *h, int *count)
> +{
> + int i,j,k=0;
> + unsigned int code;
> + // build size list for each symbol (from JPEG spec)
> + for (i=0; i < 16; ++i)
> + for (j=0; j < count[i]; ++j)
> + h->size[k++] = (stbi_uc) (i+1);
> + h->size[k] = 0;
> +
> + // compute actual symbols (from jpeg spec)
> + code = 0;
> + k = 0;
> + for(j=1; j <= 16; ++j) {
> + // compute delta to add to code to compute symbol id
> + h->delta[j] = k - code;
> + if (h->size[k] == j) {
> + while (h->size[k] == j)
> + h->code[k++] = (stbi__uint16) (code++);
> + if (code-1 >= (1u << j)) return stbi__err("bad code lengths","Corrupt JPEG");
> + }
> + // compute largest code + 1 for this size, preshifted as needed later
> + h->maxcode[j] = code << (16-j);
> + code <<= 1;
> + }
> + h->maxcode[j] = 0xffffffff;
> +
> + // build non-spec acceleration table; 255 is flag for not-accelerated
> + memset(h->fast, 255, 1 << FAST_BITS);
> + for (i=0; i < k; ++i) {
> + int s = h->size[i];
> + if (s <= FAST_BITS) {
> + int c = h->code[i] << (FAST_BITS-s);
> + int m = 1 << (FAST_BITS-s);
> + for (j=0; j < m; ++j) {
> + h->fast[c+j] = (stbi_uc) i;
> + }
> + }
> + }
> + return 1;
> +}
> +
> +// build a table that decodes both magnitude and value of small ACs in
> +// one go.
> +static void stbi__build_fast_ac(stbi__int16 *fast_ac, stbi__huffman *h)
> +{
> + int i;
> + for (i=0; i < (1 << FAST_BITS); ++i) {
> + stbi_uc fast = h->fast[i];
> + fast_ac[i] = 0;
> + if (fast < 255) {
> + int rs = h->values[fast];
> + int run = (rs >> 4) & 15;
> + int magbits = rs & 15;
> + int len = h->size[fast];
> +
> + if (magbits && len + magbits <= FAST_BITS) {
> + // magnitude code followed by receive_extend code
> + int k = ((i << len) & ((1 << FAST_BITS) - 1)) >> (FAST_BITS - magbits);
> + int m = 1 << (magbits - 1);
> + if (k < m) k += (~0U << magbits) + 1;
> + // if the result is small enough, we can fit it in fast_ac table
> + if (k >= -128 && k <= 127)
> + fast_ac[i] = (stbi__int16) ((k * 256) + (run * 16) + (len + magbits));
> + }
> + }
> + }
> +}
> +
> +static void stbi__grow_buffer_unsafe(stbi__jpeg *j)
> +{
> + do {
> + unsigned int b = j->nomore ? 0 : stbi__get8(j->s);
> + if (b == 0xff) {
> + int c = stbi__get8(j->s);
> + while (c == 0xff) c = stbi__get8(j->s); // consume fill bytes
> + if (c != 0) {
> + j->marker = (unsigned char) c;
> + j->nomore = 1;
> + return;
> + }
> + }
> + j->code_buffer |= b << (24 - j->code_bits);
> + j->code_bits += 8;
> + } while (j->code_bits <= 24);
> +}
> +
> +// (1 << n) - 1
> +static const stbi__uint32 stbi__bmask[17]={0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535};
> +
> +// decode a jpeg huffman value from the bitstream
> +stbi_inline static int stbi__jpeg_huff_decode(stbi__jpeg *j, stbi__huffman *h)
> +{
> + unsigned int temp;
> + int c,k;
> +
> + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
> +
> + // look at the top FAST_BITS and determine what symbol ID it is,
> + // if the code is <= FAST_BITS
> + c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
> + k = h->fast[c];
> + if (k < 255) {
> + int s = h->size[k];
> + if (s > j->code_bits)
> + return -1;
> + j->code_buffer <<= s;
> + j->code_bits -= s;
> + return h->values[k];
> + }
> +
> + // naive test is to shift the code_buffer down so k bits are
> + // valid, then test against maxcode. To speed this up, we've
> + // preshifted maxcode left so that it has (16-k) 0s at the
> + // end; in other words, regardless of the number of bits, it
> + // wants to be compared against something shifted to have 16;
> + // that way we don't need to shift inside the loop.
> + temp = j->code_buffer >> 16;
> + for (k=FAST_BITS+1 ; ; ++k)
> + if (temp < h->maxcode[k])
> + break;
> + if (k == 17) {
> + // error! code not found
> + j->code_bits -= 16;
> + return -1;
> + }
> +
> + if (k > j->code_bits)
> + return -1;
> +
> + // convert the huffman code to the symbol id
> + c = ((j->code_buffer >> (32 - k)) & stbi__bmask[k]) + h->delta[k];
> + STBI_ASSERT((((j->code_buffer) >> (32 - h->size[c])) & stbi__bmask[h->size[c]]) == h->code[c]);
> +
> + // convert the id to a symbol
> + j->code_bits -= k;
> + j->code_buffer <<= k;
> + return h->values[c];
> +}
> +
> +// bias[n] = (-1<<n) + 1
> +static const int stbi__jbias[16] = {0,-1,-3,-7,-15,-31,-63,-127,-255,-511,-1023,-2047,-4095,-8191,-16383,-32767};
> +
> +// combined JPEG 'receive' and JPEG 'extend', since baseline
> +// always extends everything it receives.
> +stbi_inline static int stbi__extend_receive(stbi__jpeg *j, int n)
> +{
> + unsigned int k;
> + int sgn;
> + if (j->code_bits < n) stbi__grow_buffer_unsafe(j);
> +
> + sgn = (stbi__int32)j->code_buffer >> 31; // sign bit is always in MSB
> + k = stbi_lrot(j->code_buffer, n);
> + if (n < 0 || n >= (int) (sizeof(stbi__bmask)/sizeof(*stbi__bmask))) return 0;
> + j->code_buffer = k & ~stbi__bmask[n];
> + k &= stbi__bmask[n];
> + j->code_bits -= n;
> + return k + (stbi__jbias[n] & ~sgn);
> +}
> +
> +// get some unsigned bits
> +stbi_inline static int stbi__jpeg_get_bits(stbi__jpeg *j, int n)
> +{
> + unsigned int k;
> + if (j->code_bits < n) stbi__grow_buffer_unsafe(j);
> + k = stbi_lrot(j->code_buffer, n);
> + j->code_buffer = k & ~stbi__bmask[n];
> + k &= stbi__bmask[n];
> + j->code_bits -= n;
> + return k;
> +}
> +
> +stbi_inline static int stbi__jpeg_get_bit(stbi__jpeg *j)
> +{
> + unsigned int k;
> + if (j->code_bits < 1) stbi__grow_buffer_unsafe(j);
> + k = j->code_buffer;
> + j->code_buffer <<= 1;
> + --j->code_bits;
> + return k & 0x80000000;
> +}
> +
> +// given a value that's at position X in the zigzag stream,
> +// where does it appear in the 8x8 matrix coded as row-major?
> +static const stbi_uc stbi__jpeg_dezigzag[64+15] =
> +{
> + 0, 1, 8, 16, 9, 2, 3, 10,
> + 17, 24, 32, 25, 18, 11, 4, 5,
> + 12, 19, 26, 33, 40, 48, 41, 34,
> + 27, 20, 13, 6, 7, 14, 21, 28,
> + 35, 42, 49, 56, 57, 50, 43, 36,
> + 29, 22, 15, 23, 30, 37, 44, 51,
> + 58, 59, 52, 45, 38, 31, 39, 46,
> + 53, 60, 61, 54, 47, 55, 62, 63,
> + // let corrupt input sample past end
> + 63, 63, 63, 63, 63, 63, 63, 63,
> + 63, 63, 63, 63, 63, 63, 63
> +};
> +
> +// decode one 64-entry block--
> +static int stbi__jpeg_decode_block(stbi__jpeg *j, short data[64], stbi__huffman *hdc, stbi__huffman *hac, stbi__int16 *fac, int b, stbi__uint16 *dequant)
> +{
> + int diff,dc,k;
> + int t;
> +
> + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
> + t = stbi__jpeg_huff_decode(j, hdc);
> + if (t < 0) return stbi__err("bad huffman code","Corrupt JPEG");
> +
> + // 0 all the ac values now so we can do it 32-bits at a time
> + memset(data,0,64*sizeof(data[0]));
> +
> + diff = t ? stbi__extend_receive(j, t) : 0;
> + dc = j->img_comp[b].dc_pred + diff;
> + j->img_comp[b].dc_pred = dc;
> + data[0] = (short) (dc * dequant[0]);
> +
> + // decode AC components, see JPEG spec
> + k = 1;
> + do {
> + unsigned int zig;
> + int c,r,s;
> + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
> + c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
> + r = fac[c];
> + if (r) { // fast-AC path
> + k += (r >> 4) & 15; // run
> + s = r & 15; // combined length
> + j->code_buffer <<= s;
> + j->code_bits -= s;
> + // decode into unzigzag'd location
> + zig = stbi__jpeg_dezigzag[k++];
> + data[zig] = (short) ((r >> 8) * dequant[zig]);
> + } else {
> + int rs = stbi__jpeg_huff_decode(j, hac);
> + if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
> + s = rs & 15;
> + r = rs >> 4;
> + if (s == 0) {
> + if (rs != 0xf0) break; // end block
> + k += 16;
> + } else {
> + k += r;
> + // decode into unzigzag'd location
> + zig = stbi__jpeg_dezigzag[k++];
> + data[zig] = (short) (stbi__extend_receive(j,s) * dequant[zig]);
> + }
> + }
> + } while (k < 64);
> + return 1;
> +}
> +
> +static int stbi__jpeg_decode_block_prog_dc(stbi__jpeg *j, short data[64], stbi__huffman *hdc, int b)
> +{
> + int diff,dc;
> + int t;
> + if (j->spec_end != 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
> +
> + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
> +
> + if (j->succ_high == 0) {
> + // first scan for DC coefficient, must be first
> + memset(data,0,64*sizeof(data[0])); // 0 all the ac values now
> + t = stbi__jpeg_huff_decode(j, hdc);
> + if (t == -1) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
> + diff = t ? stbi__extend_receive(j, t) : 0;
> +
> + dc = j->img_comp[b].dc_pred + diff;
> + j->img_comp[b].dc_pred = dc;
> + data[0] = (short) (dc << j->succ_low);
> + } else {
> + // refinement scan for DC coefficient
> + if (stbi__jpeg_get_bit(j))
> + data[0] += (short) (1 << j->succ_low);
> + }
> + return 1;
> +}
> +
> +// @OPTIMIZE: store non-zigzagged during the decode passes,
> +// and only de-zigzag when dequantizing
> +static int stbi__jpeg_decode_block_prog_ac(stbi__jpeg *j, short data[64], stbi__huffman *hac, stbi__int16 *fac)
> +{
> + int k;
> + if (j->spec_start == 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
> +
> + if (j->succ_high == 0) {
> + int shift = j->succ_low;
> +
> + if (j->eob_run) {
> + --j->eob_run;
> + return 1;
> + }
> +
> + k = j->spec_start;
> + do {
> + unsigned int zig;
> + int c,r,s;
> + if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
> + c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
> + r = fac[c];
> + if (r) { // fast-AC path
> + k += (r >> 4) & 15; // run
> + s = r & 15; // combined length
> + j->code_buffer <<= s;
> + j->code_bits -= s;
> + zig = stbi__jpeg_dezigzag[k++];
> + data[zig] = (short) ((r >> 8) << shift);
> + } else {
> + int rs = stbi__jpeg_huff_decode(j, hac);
> + if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
> + s = rs & 15;
> + r = rs >> 4;
> + if (s == 0) {
> + if (r < 15) {
> + j->eob_run = (1 << r);
> + if (r)
> + j->eob_run += stbi__jpeg_get_bits(j, r);
> + --j->eob_run;
> + break;
> + }
> + k += 16;
> + } else {
> + k += r;
> + zig = stbi__jpeg_dezigzag[k++];
> + data[zig] = (short) (stbi__extend_receive(j,s) << shift);
> + }
> + }
> + } while (k <= j->spec_end);
> + } else {
> + // refinement scan for these AC coefficients
> +
> + short bit = (short) (1 << j->succ_low);
> +
> + if (j->eob_run) {
> + --j->eob_run;
> + for (k = j->spec_start; k <= j->spec_end; ++k) {
> + short *p = &data[stbi__jpeg_dezigzag[k]];
> + if (*p != 0)
> + if (stbi__jpeg_get_bit(j))
> + if ((*p & bit)==0) {
> + if (*p > 0)
> + *p += bit;
> + else
> + *p -= bit;
> + }
> + }
> + } else {
> + k = j->spec_start;
> + do {
> + int r,s;
> + int rs = stbi__jpeg_huff_decode(j, hac); // @OPTIMIZE see if we can use the fast path here, advance-by-r is so slow, eh
> + if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
> + s = rs & 15;
> + r = rs >> 4;
> + if (s == 0) {
> + if (r < 15) {
> + j->eob_run = (1 << r) - 1;
> + if (r)
> + j->eob_run += stbi__jpeg_get_bits(j, r);
> + r = 64; // force end of block
> + } else {
> + // r=15 s=0 should write 16 0s, so we just do
> + // a run of 15 0s and then write s (which is 0),
> + // so we don't have to do anything special here
> + }
> + } else {
> + if (s != 1) return stbi__err("bad huffman code", "Corrupt JPEG");
> + // sign bit
> + if (stbi__jpeg_get_bit(j))
> + s = bit;
> + else
> + s = -bit;
> + }
> +
> + // advance by r
> + while (k <= j->spec_end) {
> + short *p = &data[stbi__jpeg_dezigzag[k++]];
> + if (*p != 0) {
> + if (stbi__jpeg_get_bit(j))
> + if ((*p & bit)==0) {
> + if (*p > 0)
> + *p += bit;
> + else
> + *p -= bit;
> + }
> + } else {
> + if (r == 0) {
> + *p = (short) s;
> + break;
> + }
> + --r;
> + }
> + }
> + } while (k <= j->spec_end);
> + }
> + }
> + return 1;
> +}
> +
> +// take a -128..127 value and stbi__clamp it and convert to 0..255
> +stbi_inline static stbi_uc stbi__clamp(int x)
> +{
> + // trick to use a single test to catch both cases
> + if ((unsigned int) x > 255) {
> + if (x < 0) return 0;
> + if (x > 255) return 255;
> + }
> + return (stbi_uc) x;
> +}
> +
> +#define stbi__f2f(x) ((int) (((x) * 4096 + 0.5)))
> +#define stbi__fsh(x) ((x) * 4096)
> +
> +// derived from jidctint -- DCT_ISLOW
> +#define STBI__IDCT_1D(s0,s1,s2,s3,s4,s5,s6,s7) \
> + int t0,t1,t2,t3,p1,p2,p3,p4,p5,x0,x1,x2,x3; \
> + p2 = s2; \
> + p3 = s6; \
> + p1 = (p2+p3) * stbi__f2f(0.5411961f); \
> + t2 = p1 + p3*stbi__f2f(-1.847759065f); \
> + t3 = p1 + p2*stbi__f2f( 0.765366865f); \
> + p2 = s0; \
> + p3 = s4; \
> + t0 = stbi__fsh(p2+p3); \
> + t1 = stbi__fsh(p2-p3); \
> + x0 = t0+t3; \
> + x3 = t0-t3; \
> + x1 = t1+t2; \
> + x2 = t1-t2; \
> + t0 = s7; \
> + t1 = s5; \
> + t2 = s3; \
> + t3 = s1; \
> + p3 = t0+t2; \
> + p4 = t1+t3; \
> + p1 = t0+t3; \
> + p2 = t1+t2; \
> + p5 = (p3+p4)*stbi__f2f( 1.175875602f); \
> + t0 = t0*stbi__f2f( 0.298631336f); \
> + t1 = t1*stbi__f2f( 2.053119869f); \
> + t2 = t2*stbi__f2f( 3.072711026f); \
> + t3 = t3*stbi__f2f( 1.501321110f); \
> + p1 = p5 + p1*stbi__f2f(-0.899976223f); \
> + p2 = p5 + p2*stbi__f2f(-2.562915447f); \
> + p3 = p3*stbi__f2f(-1.961570560f); \
> + p4 = p4*stbi__f2f(-0.390180644f); \
> + t3 += p1+p4; \
> + t2 += p2+p3; \
> + t1 += p2+p4; \
> + t0 += p1+p3;
> +
> +static void stbi__idct_block(stbi_uc *out, int out_stride, short data[64])
> +{
> + int i,val[64],*v=val;
> + stbi_uc *o;
> + short *d = data;
> +
> + // columns
> + for (i=0; i < 8; ++i,++d, ++v) {
> + // if all zeroes, shortcut -- this avoids dequantizing 0s and IDCTing
> + if (d[ 8]==0 && d[16]==0 && d[24]==0 && d[32]==0
> + && d[40]==0 && d[48]==0 && d[56]==0) {
> + // no shortcut 0 seconds
> + // (1|2|3|4|5|6|7)==0 0 seconds
> + // all separate -0.047 seconds
> + // 1 && 2|3 && 4|5 && 6|7: -0.047 seconds
> + int dcterm = d[0]*4;
> + v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm;
> + } else {
> + STBI__IDCT_1D(d[ 0],d[ 8],d[16],d[24],d[32],d[40],d[48],d[56])
> + // constants scaled things up by 1<<12; let's bring them back
> + // down, but keep 2 extra bits of precision
> + x0 += 512; x1 += 512; x2 += 512; x3 += 512;
> + v[ 0] = (x0+t3) >> 10;
> + v[56] = (x0-t3) >> 10;
> + v[ 8] = (x1+t2) >> 10;
> + v[48] = (x1-t2) >> 10;
> + v[16] = (x2+t1) >> 10;
> + v[40] = (x2-t1) >> 10;
> + v[24] = (x3+t0) >> 10;
> + v[32] = (x3-t0) >> 10;
> + }
> + }
> +
> + for (i=0, v=val, o=out; i < 8; ++i,v+=8,o+=out_stride) {
> + // no fast case since the first 1D IDCT spread components out
> + STBI__IDCT_1D(v[0],v[1],v[2],v[3],v[4],v[5],v[6],v[7])
> + // constants scaled things up by 1<<12, plus we had 1<<2 from first
> + // loop, plus horizontal and vertical each scale by sqrt(8) so together
> + // we've got an extra 1<<3, so 1<<17 total we need to remove.
> + // so we want to round that, which means adding 0.5 * 1<<17,
> + // aka 65536. Also, we'll end up with -128 to 127 that we want
> + // to encode as 0..255 by adding 128, so we'll add that before the shift
> + x0 += 65536 + (128<<17);
> + x1 += 65536 + (128<<17);
> + x2 += 65536 + (128<<17);
> + x3 += 65536 + (128<<17);
> + // tried computing the shifts into temps, or'ing the temps to see
> + // if any were out of range, but that was slower
> + o[0] = stbi__clamp((x0+t3) >> 17);
> + o[7] = stbi__clamp((x0-t3) >> 17);
> + o[1] = stbi__clamp((x1+t2) >> 17);
> + o[6] = stbi__clamp((x1-t2) >> 17);
> + o[2] = stbi__clamp((x2+t1) >> 17);
> + o[5] = stbi__clamp((x2-t1) >> 17);
> + o[3] = stbi__clamp((x3+t0) >> 17);
> + o[4] = stbi__clamp((x3-t0) >> 17);
> + }
> +}
> +
> +#ifdef STBI_SSE2
> +// sse2 integer IDCT. not the fastest possible implementation but it
> +// produces bit-identical results to the generic C version so it's
> +// fully "transparent".
> +static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64])
> +{
> + // This is constructed to match our regular (generic) integer IDCT exactly.
> + __m128i row0, row1, row2, row3, row4, row5, row6, row7;
> + __m128i tmp;
> +
> + // dot product constant: even elems=x, odd elems=y
> + #define dct_const(x,y) _mm_setr_epi16((x),(y),(x),(y),(x),(y),(x),(y))
> +
> + // out(0) = c0[even]*x + c0[odd]*y (c0, x, y 16-bit, out 32-bit)
> + // out(1) = c1[even]*x + c1[odd]*y
> + #define dct_rot(out0,out1, x,y,c0,c1) \
> + __m128i c0##lo = _mm_unpacklo_epi16((x),(y)); \
> + __m128i c0##hi = _mm_unpackhi_epi16((x),(y)); \
> + __m128i out0##_l = _mm_madd_epi16(c0##lo, c0); \
> + __m128i out0##_h = _mm_madd_epi16(c0##hi, c0); \
> + __m128i out1##_l = _mm_madd_epi16(c0##lo, c1); \
> + __m128i out1##_h = _mm_madd_epi16(c0##hi, c1)
> +
> + // out = in << 12 (in 16-bit, out 32-bit)
> + #define dct_widen(out, in) \
> + __m128i out##_l = _mm_srai_epi32(_mm_unpacklo_epi16(_mm_setzero_si128(), (in)), 4); \
> + __m128i out##_h = _mm_srai_epi32(_mm_unpackhi_epi16(_mm_setzero_si128(), (in)), 4)
> +
> + // wide add
> + #define dct_wadd(out, a, b) \
> + __m128i out##_l = _mm_add_epi32(a##_l, b##_l); \
> + __m128i out##_h = _mm_add_epi32(a##_h, b##_h)
> +
> + // wide sub
> + #define dct_wsub(out, a, b) \
> + __m128i out##_l = _mm_sub_epi32(a##_l, b##_l); \
> + __m128i out##_h = _mm_sub_epi32(a##_h, b##_h)
> +
> + // butterfly a/b, add bias, then shift by "s" and pack
> + #define dct_bfly32o(out0, out1, a,b,bias,s) \
> + { \
> + __m128i abiased_l = _mm_add_epi32(a##_l, bias); \
> + __m128i abiased_h = _mm_add_epi32(a##_h, bias); \
> + dct_wadd(sum, abiased, b); \
> + dct_wsub(dif, abiased, b); \
> + out0 = _mm_packs_epi32(_mm_srai_epi32(sum_l, s), _mm_srai_epi32(sum_h, s)); \
> + out1 = _mm_packs_epi32(_mm_srai_epi32(dif_l, s), _mm_srai_epi32(dif_h, s)); \
> + }
> +
> + // 8-bit interleave step (for transposes)
> + #define dct_interleave8(a, b) \
> + tmp = a; \
> + a = _mm_unpacklo_epi8(a, b); \
> + b = _mm_unpackhi_epi8(tmp, b)
> +
> + // 16-bit interleave step (for transposes)
> + #define dct_interleave16(a, b) \
> + tmp = a; \
> + a = _mm_unpacklo_epi16(a, b); \
> + b = _mm_unpackhi_epi16(tmp, b)
> +
> + #define dct_pass(bias,shift) \
> + { \
> + /* even part */ \
> + dct_rot(t2e,t3e, row2,row6, rot0_0,rot0_1); \
> + __m128i sum04 = _mm_add_epi16(row0, row4); \
> + __m128i dif04 = _mm_sub_epi16(row0, row4); \
> + dct_widen(t0e, sum04); \
> + dct_widen(t1e, dif04); \
> + dct_wadd(x0, t0e, t3e); \
> + dct_wsub(x3, t0e, t3e); \
> + dct_wadd(x1, t1e, t2e); \
> + dct_wsub(x2, t1e, t2e); \
> + /* odd part */ \
> + dct_rot(y0o,y2o, row7,row3, rot2_0,rot2_1); \
> + dct_rot(y1o,y3o, row5,row1, rot3_0,rot3_1); \
> + __m128i sum17 = _mm_add_epi16(row1, row7); \
> + __m128i sum35 = _mm_add_epi16(row3, row5); \
> + dct_rot(y4o,y5o, sum17,sum35, rot1_0,rot1_1); \
> + dct_wadd(x4, y0o, y4o); \
> + dct_wadd(x5, y1o, y5o); \
> + dct_wadd(x6, y2o, y5o); \
> + dct_wadd(x7, y3o, y4o); \
> + dct_bfly32o(row0,row7, x0,x7,bias,shift); \
> + dct_bfly32o(row1,row6, x1,x6,bias,shift); \
> + dct_bfly32o(row2,row5, x2,x5,bias,shift); \
> + dct_bfly32o(row3,row4, x3,x4,bias,shift); \
> + }
> +
> + __m128i rot0_0 = dct_const(stbi__f2f(0.5411961f), stbi__f2f(0.5411961f) + stbi__f2f(-1.847759065f));
> + __m128i rot0_1 = dct_const(stbi__f2f(0.5411961f) + stbi__f2f( 0.765366865f), stbi__f2f(0.5411961f));
> + __m128i rot1_0 = dct_const(stbi__f2f(1.175875602f) + stbi__f2f(-0.899976223f), stbi__f2f(1.175875602f));
> + __m128i rot1_1 = dct_const(stbi__f2f(1.175875602f), stbi__f2f(1.175875602f) + stbi__f2f(-2.562915447f));
> + __m128i rot2_0 = dct_const(stbi__f2f(-1.961570560f) + stbi__f2f( 0.298631336f), stbi__f2f(-1.961570560f));
> + __m128i rot2_1 = dct_const(stbi__f2f(-1.961570560f), stbi__f2f(-1.961570560f) + stbi__f2f( 3.072711026f));
> + __m128i rot3_0 = dct_const(stbi__f2f(-0.390180644f) + stbi__f2f( 2.053119869f), stbi__f2f(-0.390180644f));
> + __m128i rot3_1 = dct_const(stbi__f2f(-0.390180644f), stbi__f2f(-0.390180644f) + stbi__f2f( 1.501321110f));
> +
> + // rounding biases in column/row passes, see stbi__idct_block for explanation.
> + __m128i bias_0 = _mm_set1_epi32(512);
> + __m128i bias_1 = _mm_set1_epi32(65536 + (128<<17));
> +
> + // load
> + row0 = _mm_load_si128((const __m128i *) (data + 0*8));
> + row1 = _mm_load_si128((const __m128i *) (data + 1*8));
> + row2 = _mm_load_si128((const __m128i *) (data + 2*8));
> + row3 = _mm_load_si128((const __m128i *) (data + 3*8));
> + row4 = _mm_load_si128((const __m128i *) (data + 4*8));
> + row5 = _mm_load_si128((const __m128i *) (data + 5*8));
> + row6 = _mm_load_si128((const __m128i *) (data + 6*8));
> + row7 = _mm_load_si128((const __m128i *) (data + 7*8));
> +
> + // column pass
> + dct_pass(bias_0, 10);
> +
> + {
> + // 16bit 8x8 transpose pass 1
> + dct_interleave16(row0, row4);
> + dct_interleave16(row1, row5);
> + dct_interleave16(row2, row6);
> + dct_interleave16(row3, row7);
> +
> + // transpose pass 2
> + dct_interleave16(row0, row2);
> + dct_interleave16(row1, row3);
> + dct_interleave16(row4, row6);
> + dct_interleave16(row5, row7);
> +
> + // transpose pass 3
> + dct_interleave16(row0, row1);
> + dct_interleave16(row2, row3);
> + dct_interleave16(row4, row5);
> + dct_interleave16(row6, row7);
> + }
> +
> + // row pass
> + dct_pass(bias_1, 17);
> +
> + {
> + // pack
> + __m128i p0 = _mm_packus_epi16(row0, row1); // a0a1a2a3...a7b0b1b2b3...b7
> + __m128i p1 = _mm_packus_epi16(row2, row3);
> + __m128i p2 = _mm_packus_epi16(row4, row5);
> + __m128i p3 = _mm_packus_epi16(row6, row7);
> +
> + // 8bit 8x8 transpose pass 1
> + dct_interleave8(p0, p2); // a0e0a1e1...
> + dct_interleave8(p1, p3); // c0g0c1g1...
> +
> + // transpose pass 2
> + dct_interleave8(p0, p1); // a0c0e0g0...
> + dct_interleave8(p2, p3); // b0d0f0h0...
> +
> + // transpose pass 3
> + dct_interleave8(p0, p2); // a0b0c0d0...
> + dct_interleave8(p1, p3); // a4b4c4d4...
> +
> + // store
> + _mm_storel_epi64((__m128i *) out, p0); out += out_stride;
> + _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p0, 0x4e)); out += out_stride;
> + _mm_storel_epi64((__m128i *) out, p2); out += out_stride;
> + _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p2, 0x4e)); out += out_stride;
> + _mm_storel_epi64((__m128i *) out, p1); out += out_stride;
> + _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p1, 0x4e)); out += out_stride;
> + _mm_storel_epi64((__m128i *) out, p3); out += out_stride;
> + _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p3, 0x4e));
> + }
> +
> +#undef dct_const
> +#undef dct_rot
> +#undef dct_widen
> +#undef dct_wadd
> +#undef dct_wsub
> +#undef dct_bfly32o
> +#undef dct_interleave8
> +#undef dct_interleave16
> +#undef dct_pass
> +}
> +
> +#endif // STBI_SSE2
> +
> +#ifdef STBI_NEON
> +
> +// NEON integer IDCT. should produce bit-identical
> +// results to the generic C version.
> +static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64])
> +{
> + int16x8_t row0, row1, row2, row3, row4, row5, row6, row7;
> +
> + int16x4_t rot0_0 = vdup_n_s16(stbi__f2f(0.5411961f));
> + int16x4_t rot0_1 = vdup_n_s16(stbi__f2f(-1.847759065f));
> + int16x4_t rot0_2 = vdup_n_s16(stbi__f2f( 0.765366865f));
> + int16x4_t rot1_0 = vdup_n_s16(stbi__f2f( 1.175875602f));
> + int16x4_t rot1_1 = vdup_n_s16(stbi__f2f(-0.899976223f));
> + int16x4_t rot1_2 = vdup_n_s16(stbi__f2f(-2.562915447f));
> + int16x4_t rot2_0 = vdup_n_s16(stbi__f2f(-1.961570560f));
> + int16x4_t rot2_1 = vdup_n_s16(stbi__f2f(-0.390180644f));
> + int16x4_t rot3_0 = vdup_n_s16(stbi__f2f( 0.298631336f));
> + int16x4_t rot3_1 = vdup_n_s16(stbi__f2f( 2.053119869f));
> + int16x4_t rot3_2 = vdup_n_s16(stbi__f2f( 3.072711026f));
> + int16x4_t rot3_3 = vdup_n_s16(stbi__f2f( 1.501321110f));
> +
> +#define dct_long_mul(out, inq, coeff) \
> + int32x4_t out##_l = vmull_s16(vget_low_s16(inq), coeff); \
> + int32x4_t out##_h = vmull_s16(vget_high_s16(inq), coeff)
> +
> +#define dct_long_mac(out, acc, inq, coeff) \
> + int32x4_t out##_l = vmlal_s16(acc##_l, vget_low_s16(inq), coeff); \
> + int32x4_t out##_h = vmlal_s16(acc##_h, vget_high_s16(inq), coeff)
> +
> +#define dct_widen(out, inq) \
> + int32x4_t out##_l = vshll_n_s16(vget_low_s16(inq), 12); \
> + int32x4_t out##_h = vshll_n_s16(vget_high_s16(inq), 12)
> +
> +// wide add
> +#define dct_wadd(out, a, b) \
> + int32x4_t out##_l = vaddq_s32(a##_l, b##_l); \
> + int32x4_t out##_h = vaddq_s32(a##_h, b##_h)
> +
> +// wide sub
> +#define dct_wsub(out, a, b) \
> + int32x4_t out##_l = vsubq_s32(a##_l, b##_l); \
> + int32x4_t out##_h = vsubq_s32(a##_h, b##_h)
> +
> +// butterfly a/b, then shift using "shiftop" by "s" and pack
> +#define dct_bfly32o(out0,out1, a,b,shiftop,s) \
> + { \
> + dct_wadd(sum, a, b); \
> + dct_wsub(dif, a, b); \
> + out0 = vcombine_s16(shiftop(sum_l, s), shiftop(sum_h, s)); \
> + out1 = vcombine_s16(shiftop(dif_l, s), shiftop(dif_h, s)); \
> + }
> +
> +#define dct_pass(shiftop, shift) \
> + { \
> + /* even part */ \
> + int16x8_t sum26 = vaddq_s16(row2, row6); \
> + dct_long_mul(p1e, sum26, rot0_0); \
> + dct_long_mac(t2e, p1e, row6, rot0_1); \
> + dct_long_mac(t3e, p1e, row2, rot0_2); \
> + int16x8_t sum04 = vaddq_s16(row0, row4); \
> + int16x8_t dif04 = vsubq_s16(row0, row4); \
> + dct_widen(t0e, sum04); \
> + dct_widen(t1e, dif04); \
> + dct_wadd(x0, t0e, t3e); \
> + dct_wsub(x3, t0e, t3e); \
> + dct_wadd(x1, t1e, t2e); \
> + dct_wsub(x2, t1e, t2e); \
> + /* odd part */ \
> + int16x8_t sum15 = vaddq_s16(row1, row5); \
> + int16x8_t sum17 = vaddq_s16(row1, row7); \
> + int16x8_t sum35 = vaddq_s16(row3, row5); \
> + int16x8_t sum37 = vaddq_s16(row3, row7); \
> + int16x8_t sumodd = vaddq_s16(sum17, sum35); \
> + dct_long_mul(p5o, sumodd, rot1_0); \
> + dct_long_mac(p1o, p5o, sum17, rot1_1); \
> + dct_long_mac(p2o, p5o, sum35, rot1_2); \
> + dct_long_mul(p3o, sum37, rot2_0); \
> + dct_long_mul(p4o, sum15, rot2_1); \
> + dct_wadd(sump13o, p1o, p3o); \
> + dct_wadd(sump24o, p2o, p4o); \
> + dct_wadd(sump23o, p2o, p3o); \
> + dct_wadd(sump14o, p1o, p4o); \
> + dct_long_mac(x4, sump13o, row7, rot3_0); \
> + dct_long_mac(x5, sump24o, row5, rot3_1); \
> + dct_long_mac(x6, sump23o, row3, rot3_2); \
> + dct_long_mac(x7, sump14o, row1, rot3_3); \
> + dct_bfly32o(row0,row7, x0,x7,shiftop,shift); \
> + dct_bfly32o(row1,row6, x1,x6,shiftop,shift); \
> + dct_bfly32o(row2,row5, x2,x5,shiftop,shift); \
> + dct_bfly32o(row3,row4, x3,x4,shiftop,shift); \
> + }
> +
> + // load
> + row0 = vld1q_s16(data + 0*8);
> + row1 = vld1q_s16(data + 1*8);
> + row2 = vld1q_s16(data + 2*8);
> + row3 = vld1q_s16(data + 3*8);
> + row4 = vld1q_s16(data + 4*8);
> + row5 = vld1q_s16(data + 5*8);
> + row6 = vld1q_s16(data + 6*8);
> + row7 = vld1q_s16(data + 7*8);
> +
> + // add DC bias
> + row0 = vaddq_s16(row0, vsetq_lane_s16(1024, vdupq_n_s16(0), 0));
> +
> + // column pass
> + dct_pass(vrshrn_n_s32, 10);
> +
> + // 16bit 8x8 transpose
> + {
> +// these three map to a single VTRN.16, VTRN.32, and VSWP, respectively.
> +// whether compilers actually get this is another story, sadly.
> +#define dct_trn16(x, y) { int16x8x2_t t = vtrnq_s16(x, y); x = t.val[0]; y = t.val[1]; }
> +#define dct_trn32(x, y) { int32x4x2_t t = vtrnq_s32(vreinterpretq_s32_s16(x), vreinterpretq_s32_s16(y)); x = vreinterpretq_s16_s32(t.val[0]); y = vreinterpretq_s16_s32(t.val[1]); }
> +#define dct_trn64(x, y) { int16x8_t x0 = x; int16x8_t y0 = y; x = vcombine_s16(vget_low_s16(x0), vget_low_s16(y0)); y = vcombine_s16(vget_high_s16(x0), vget_high_s16(y0)); }
> +
> + // pass 1
> + dct_trn16(row0, row1); // a0b0a2b2a4b4a6b6
> + dct_trn16(row2, row3);
> + dct_trn16(row4, row5);
> + dct_trn16(row6, row7);
> +
> + // pass 2
> + dct_trn32(row0, row2); // a0b0c0d0a4b4c4d4
> + dct_trn32(row1, row3);
> + dct_trn32(row4, row6);
> + dct_trn32(row5, row7);
> +
> + // pass 3
> + dct_trn64(row0, row4); // a0b0c0d0e0f0g0h0
> + dct_trn64(row1, row5);
> + dct_trn64(row2, row6);
> + dct_trn64(row3, row7);
> +
> +#undef dct_trn16
> +#undef dct_trn32
> +#undef dct_trn64
> + }
> +
> + // row pass
> + // vrshrn_n_s32 only supports shifts up to 16, we need
> + // 17. so do a non-rounding shift of 16 first then follow
> + // up with a rounding shift by 1.
> + dct_pass(vshrn_n_s32, 16);
> +
> + {
> + // pack and round
> + uint8x8_t p0 = vqrshrun_n_s16(row0, 1);
> + uint8x8_t p1 = vqrshrun_n_s16(row1, 1);
> + uint8x8_t p2 = vqrshrun_n_s16(row2, 1);
> + uint8x8_t p3 = vqrshrun_n_s16(row3, 1);
> + uint8x8_t p4 = vqrshrun_n_s16(row4, 1);
> + uint8x8_t p5 = vqrshrun_n_s16(row5, 1);
> + uint8x8_t p6 = vqrshrun_n_s16(row6, 1);
> + uint8x8_t p7 = vqrshrun_n_s16(row7, 1);
> +
> + // again, these can translate into one instruction, but often don't.
> +#define dct_trn8_8(x, y) { uint8x8x2_t t = vtrn_u8(x, y); x = t.val[0]; y = t.val[1]; }
> +#define dct_trn8_16(x, y) { uint16x4x2_t t = vtrn_u16(vreinterpret_u16_u8(x), vreinterpret_u16_u8(y)); x = vreinterpret_u8_u16(t.val[0]); y = vreinterpret_u8_u16(t.val[1]); }
> +#define dct_trn8_32(x, y) { uint32x2x2_t t = vtrn_u32(vreinterpret_u32_u8(x), vreinterpret_u32_u8(y)); x = vreinterpret_u8_u32(t.val[0]); y = vreinterpret_u8_u32(t.val[1]); }
> +
> + // sadly can't use interleaved stores here since we only write
> + // 8 bytes to each scan line!
> +
> + // 8x8 8-bit transpose pass 1
> + dct_trn8_8(p0, p1);
> + dct_trn8_8(p2, p3);
> + dct_trn8_8(p4, p5);
> + dct_trn8_8(p6, p7);
> +
> + // pass 2
> + dct_trn8_16(p0, p2);
> + dct_trn8_16(p1, p3);
> + dct_trn8_16(p4, p6);
> + dct_trn8_16(p5, p7);
> +
> + // pass 3
> + dct_trn8_32(p0, p4);
> + dct_trn8_32(p1, p5);
> + dct_trn8_32(p2, p6);
> + dct_trn8_32(p3, p7);
> +
> + // store
> + vst1_u8(out, p0); out += out_stride;
> + vst1_u8(out, p1); out += out_stride;
> + vst1_u8(out, p2); out += out_stride;
> + vst1_u8(out, p3); out += out_stride;
> + vst1_u8(out, p4); out += out_stride;
> + vst1_u8(out, p5); out += out_stride;
> + vst1_u8(out, p6); out += out_stride;
> + vst1_u8(out, p7);
> +
> +#undef dct_trn8_8
> +#undef dct_trn8_16
> +#undef dct_trn8_32
> + }
> +
> +#undef dct_long_mul
> +#undef dct_long_mac
> +#undef dct_widen
> +#undef dct_wadd
> +#undef dct_wsub
> +#undef dct_bfly32o
> +#undef dct_pass
> +}
> +
> +#endif // STBI_NEON
> +
> +#define STBI__MARKER_none 0xff
> +// if there's a pending marker from the entropy stream, return that
> +// otherwise, fetch from the stream and get a marker. if there's no
> +// marker, return 0xff, which is never a valid marker value
> +static stbi_uc stbi__get_marker(stbi__jpeg *j)
> +{
> + stbi_uc x;
> + if (j->marker != STBI__MARKER_none) { x = j->marker; j->marker = STBI__MARKER_none; return x; }
> + x = stbi__get8(j->s);
> + if (x != 0xff) return STBI__MARKER_none;
> + while (x == 0xff)
> + x = stbi__get8(j->s); // consume repeated 0xff fill bytes
> + return x;
> +}
> +
> +// in each scan, we'll have scan_n components, and the order
> +// of the components is specified by order[]
> +#define STBI__RESTART(x) ((x) >= 0xd0 && (x) <= 0xd7)
> +
> +// after a restart interval, stbi__jpeg_reset the entropy decoder and
> +// the dc prediction
> +static void stbi__jpeg_reset(stbi__jpeg *j)
> +{
> + j->code_bits = 0;
> + j->code_buffer = 0;
> + j->nomore = 0;
> + j->img_comp[0].dc_pred = j->img_comp[1].dc_pred = j->img_comp[2].dc_pred = j->img_comp[3].dc_pred = 0;
> + j->marker = STBI__MARKER_none;
> + j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff;
> + j->eob_run = 0;
> + // no more than 1<<31 MCUs if no restart_interal? that's plenty safe,
> + // since we don't even allow 1<<30 pixels
> +}
> +
> +static int stbi__parse_entropy_coded_data(stbi__jpeg *z)
> +{
> + stbi__jpeg_reset(z);
> + if (!z->progressive) {
> + if (z->scan_n == 1) {
> + int i,j;
> + STBI_SIMD_ALIGN(short, data[64]);
> + int n = z->order[0];
> + // non-interleaved data, we just need to process one block at a time,
> + // in trivial scanline order
> + // number of blocks to do just depends on how many actual "pixels" this
> + // component has, independent of interleaved MCU blocking and such
> + int w = (z->img_comp[n].x+7) >> 3;
> + int h = (z->img_comp[n].y+7) >> 3;
> + for (j=0; j < h; ++j) {
> + for (i=0; i < w; ++i) {
> + int ha = z->img_comp[n].ha;
> + if (!stbi__jpeg_decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0;
> + z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data);
> + // every data block is an MCU, so countdown the restart interval
> + if (--z->todo <= 0) {
> + if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
> + // if it's NOT a restart, then just bail, so we get corrupt data
> + // rather than no data
> + if (!STBI__RESTART(z->marker)) return 1;
> + stbi__jpeg_reset(z);
> + }
> + }
> + }
> + return 1;
> + } else { // interleaved
> + int i,j,k,x,y;
> + STBI_SIMD_ALIGN(short, data[64]);
> + for (j=0; j < z->img_mcu_y; ++j) {
> + for (i=0; i < z->img_mcu_x; ++i) {
> + // scan an interleaved mcu... process scan_n components in order
> + for (k=0; k < z->scan_n; ++k) {
> + int n = z->order[k];
> + // scan out an mcu's worth of this component; that's just determined
> + // by the basic H and V specified for the component
> + for (y=0; y < z->img_comp[n].v; ++y) {
> + for (x=0; x < z->img_comp[n].h; ++x) {
> + int x2 = (i*z->img_comp[n].h + x)*8;
> + int y2 = (j*z->img_comp[n].v + y)*8;
> + int ha = z->img_comp[n].ha;
> + if (!stbi__jpeg_decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0;
> + z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*y2+x2, z->img_comp[n].w2, data);
> + }
> + }
> + }
> + // after all interleaved components, that's an interleaved MCU,
> + // so now count down the restart interval
> + if (--z->todo <= 0) {
> + if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
> + if (!STBI__RESTART(z->marker)) return 1;
> + stbi__jpeg_reset(z);
> + }
> + }
> + }
> + return 1;
> + }
> + } else {
> + if (z->scan_n == 1) {
> + int i,j;
> + int n = z->order[0];
> + // non-interleaved data, we just need to process one block at a time,
> + // in trivial scanline order
> + // number of blocks to do just depends on how many actual "pixels" this
> + // component has, independent of interleaved MCU blocking and such
> + int w = (z->img_comp[n].x+7) >> 3;
> + int h = (z->img_comp[n].y+7) >> 3;
> + for (j=0; j < h; ++j) {
> + for (i=0; i < w; ++i) {
> + short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w);
> + if (z->spec_start == 0) {
> + if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n))
> + return 0;
> + } else {
> + int ha = z->img_comp[n].ha;
> + if (!stbi__jpeg_decode_block_prog_ac(z, data, &z->huff_ac[ha], z->fast_ac[ha]))
> + return 0;
> + }
> + // every data block is an MCU, so countdown the restart interval
> + if (--z->todo <= 0) {
> + if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
> + if (!STBI__RESTART(z->marker)) return 1;
> + stbi__jpeg_reset(z);
> + }
> + }
> + }
> + return 1;
> + } else { // interleaved
> + int i,j,k,x,y;
> + for (j=0; j < z->img_mcu_y; ++j) {
> + for (i=0; i < z->img_mcu_x; ++i) {
> + // scan an interleaved mcu... process scan_n components in order
> + for (k=0; k < z->scan_n; ++k) {
> + int n = z->order[k];
> + // scan out an mcu's worth of this component; that's just determined
> + // by the basic H and V specified for the component
> + for (y=0; y < z->img_comp[n].v; ++y) {
> + for (x=0; x < z->img_comp[n].h; ++x) {
> + int x2 = (i*z->img_comp[n].h + x);
> + int y2 = (j*z->img_comp[n].v + y);
> + short *data = z->img_comp[n].coeff + 64 * (x2 + y2 * z->img_comp[n].coeff_w);
> + if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n))
> + return 0;
> + }
> + }
> + }
> + // after all interleaved components, that's an interleaved MCU,
> + // so now count down the restart interval
> + if (--z->todo <= 0) {
> + if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
> + if (!STBI__RESTART(z->marker)) return 1;
> + stbi__jpeg_reset(z);
> + }
> + }
> + }
> + return 1;
> + }
> + }
> +}
> +
> +static void stbi__jpeg_dequantize(short *data, stbi__uint16 *dequant)
> +{
> + int i;
> + for (i=0; i < 64; ++i)
> + data[i] *= dequant[i];
> +}
> +
> +static void stbi__jpeg_finish(stbi__jpeg *z)
> +{
> + if (z->progressive) {
> + // dequantize and idct the data
> + int i,j,n;
> + for (n=0; n < z->s->img_n; ++n) {
> + int w = (z->img_comp[n].x+7) >> 3;
> + int h = (z->img_comp[n].y+7) >> 3;
> + for (j=0; j < h; ++j) {
> + for (i=0; i < w; ++i) {
> + short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w);
> + stbi__jpeg_dequantize(data, z->dequant[z->img_comp[n].tq]);
> + z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data);
> + }
> + }
> + }
> + }
> +}
> +
> +static int stbi__process_marker(stbi__jpeg *z, int m)
> +{
> + int L;
> + switch (m) {
> + case STBI__MARKER_none: // no marker found
> + return stbi__err("expected marker","Corrupt JPEG");
> +
> + case 0xDD: // DRI - specify restart interval
> + if (stbi__get16be(z->s) != 4) return stbi__err("bad DRI len","Corrupt JPEG");
> + z->restart_interval = stbi__get16be(z->s);
> + return 1;
> +
> + case 0xDB: // DQT - define quantization table
> + L = stbi__get16be(z->s)-2;
> + while (L > 0) {
> + int q = stbi__get8(z->s);
> + int p = q >> 4, sixteen = (p != 0);
> + int t = q & 15,i;
> + if (p != 0 && p != 1) return stbi__err("bad DQT type","Corrupt JPEG");
> + if (t > 3) return stbi__err("bad DQT table","Corrupt JPEG");
> +
> + for (i=0; i < 64; ++i)
> + z->dequant[t][stbi__jpeg_dezigzag[i]] = (stbi__uint16)(sixteen ? stbi__get16be(z->s) : stbi__get8(z->s));
> + L -= (sixteen ? 129 : 65);
> + }
> + return L==0;
> +
> + case 0xC4: // DHT - define huffman table
> + L = stbi__get16be(z->s)-2;
> + while (L > 0) {
> + stbi_uc *v;
> + int sizes[16],i,n=0;
> + int q = stbi__get8(z->s);
> + int tc = q >> 4;
> + int th = q & 15;
> + if (tc > 1 || th > 3) return stbi__err("bad DHT header","Corrupt JPEG");
> + for (i=0; i < 16; ++i) {
> + sizes[i] = stbi__get8(z->s);
> + n += sizes[i];
> + }
> + L -= 17;
> + if (tc == 0) {
> + if (!stbi__build_huffman(z->huff_dc+th, sizes)) return 0;
> + v = z->huff_dc[th].values;
> + } else {
> + if (!stbi__build_huffman(z->huff_ac+th, sizes)) return 0;
> + v = z->huff_ac[th].values;
> + }
> + for (i=0; i < n; ++i)
> + v[i] = stbi__get8(z->s);
> + if (tc != 0)
> + stbi__build_fast_ac(z->fast_ac[th], z->huff_ac + th);
> + L -= n;
> + }
> + return L==0;
> + }
> +
> + // check for comment block or APP blocks
> + if ((m >= 0xE0 && m <= 0xEF) || m == 0xFE) {
> + L = stbi__get16be(z->s);
> + if (L < 2) {
> + if (m == 0xFE)
> + return stbi__err("bad COM len","Corrupt JPEG");
> + else
> + return stbi__err("bad APP len","Corrupt JPEG");
> + }
> + L -= 2;
> +
> + if (m == 0xE0 && L >= 5) { // JFIF APP0 segment
> + static const unsigned char tag[5] = {'J','F','I','F','\0'};
> + int ok = 1;
> + int i;
> + for (i=0; i < 5; ++i)
> + if (stbi__get8(z->s) != tag[i])
> + ok = 0;
> + L -= 5;
> + if (ok)
> + z->jfif = 1;
> + } else if (m == 0xEE && L >= 12) { // Adobe APP14 segment
> + static const unsigned char tag[6] = {'A','d','o','b','e','\0'};
> + int ok = 1;
> + int i;
> + for (i=0; i < 6; ++i)
> + if (stbi__get8(z->s) != tag[i])
> + ok = 0;
> + L -= 6;
> + if (ok) {
> + stbi__get8(z->s); // version
> + stbi__get16be(z->s); // flags0
> + stbi__get16be(z->s); // flags1
> + z->app14_color_transform = stbi__get8(z->s); // color transform
> + L -= 6;
> + }
> + }
> +
> + stbi__skip(z->s, L);
> + return 1;
> + }
> +
> + return stbi__err("unknown marker","Corrupt JPEG");
> +}
> +
> +// after we see SOS
> +static int stbi__process_scan_header(stbi__jpeg *z)
> +{
> + int i;
> + int Ls = stbi__get16be(z->s);
> + z->scan_n = stbi__get8(z->s);
> + if (z->scan_n < 1 || z->scan_n > 4 || z->scan_n > (int) z->s->img_n) return stbi__err("bad SOS component count","Corrupt JPEG");
> + if (Ls != 6+2*z->scan_n) return stbi__err("bad SOS len","Corrupt JPEG");
> + for (i=0; i < z->scan_n; ++i) {
> + int id = stbi__get8(z->s), which;
> + int q = stbi__get8(z->s);
> + for (which = 0; which < z->s->img_n; ++which)
> + if (z->img_comp[which].id == id)
> + break;
> + if (which == z->s->img_n) return 0; // no match
> + z->img_comp[which].hd = q >> 4; if (z->img_comp[which].hd > 3) return stbi__err("bad DC huff","Corrupt JPEG");
> + z->img_comp[which].ha = q & 15; if (z->img_comp[which].ha > 3) return stbi__err("bad AC huff","Corrupt JPEG");
> + z->order[i] = which;
> + }
> +
> + {
> + int aa;
> + z->spec_start = stbi__get8(z->s);
> + z->spec_end = stbi__get8(z->s); // should be 63, but might be 0
> + aa = stbi__get8(z->s);
> + z->succ_high = (aa >> 4);
> + z->succ_low = (aa & 15);
> + if (z->progressive) {
> + if (z->spec_start > 63 || z->spec_end > 63 || z->spec_start > z->spec_end || z->succ_high > 13 || z->succ_low > 13)
> + return stbi__err("bad SOS", "Corrupt JPEG");
> + } else {
> + if (z->spec_start != 0) return stbi__err("bad SOS","Corrupt JPEG");
> + if (z->succ_high != 0 || z->succ_low != 0) return stbi__err("bad SOS","Corrupt JPEG");
> + z->spec_end = 63;
> + }
> + }
> +
> + return 1;
> +}
> +
> +static int stbi__free_jpeg_components(stbi__jpeg *z, int ncomp, int why)
> +{
> + int i;
> + for (i=0; i < ncomp; ++i) {
> + if (z->img_comp[i].raw_data) {
> + STBI_FREE(z->img_comp[i].raw_data);
> + z->img_comp[i].raw_data = NULL;
> + z->img_comp[i].data = NULL;
> + }
> + if (z->img_comp[i].raw_coeff) {
> + STBI_FREE(z->img_comp[i].raw_coeff);
> + z->img_comp[i].raw_coeff = 0;
> + z->img_comp[i].coeff = 0;
> + }
> + if (z->img_comp[i].linebuf) {
> + STBI_FREE(z->img_comp[i].linebuf);
> + z->img_comp[i].linebuf = NULL;
> + }
> + }
> + return why;
> +}
> +
> +static int stbi__process_frame_header(stbi__jpeg *z, int scan)
> +{
> + stbi__context *s = z->s;
> + int Lf,p,i,q, h_max=1,v_max=1,c;
> + Lf = stbi__get16be(s); if (Lf < 11) return stbi__err("bad SOF len","Corrupt JPEG"); // JPEG
> + p = stbi__get8(s); if (p != 8) return stbi__err("only 8-bit","JPEG format not supported: 8-bit only"); // JPEG baseline
> + s->img_y = stbi__get16be(s); if (s->img_y == 0) return stbi__err("no header height", "JPEG format not supported: delayed height"); // Legal, but we don't handle it--but neither does IJG
> + s->img_x = stbi__get16be(s); if (s->img_x == 0) return stbi__err("0 width","Corrupt JPEG"); // JPEG requires
> + if (s->img_y > STBI_MAX_DIMENSIONS) return stbi__err("too large","Very large image (corrupt?)");
> + if (s->img_x > STBI_MAX_DIMENSIONS) return stbi__err("too large","Very large image (corrupt?)");
> + c = stbi__get8(s);
> + if (c != 3 && c != 1 && c != 4) return stbi__err("bad component count","Corrupt JPEG");
> + s->img_n = c;
> + for (i=0; i < c; ++i) {
> + z->img_comp[i].data = NULL;
> + z->img_comp[i].linebuf = NULL;
> + }
> +
> + if (Lf != 8+3*s->img_n) return stbi__err("bad SOF len","Corrupt JPEG");
> +
> + z->rgb = 0;
> + for (i=0; i < s->img_n; ++i) {
> + static const unsigned char rgb[3] = { 'R', 'G', 'B' };
> + z->img_comp[i].id = stbi__get8(s);
> + if (s->img_n == 3 && z->img_comp[i].id == rgb[i])
> + ++z->rgb;
> + q = stbi__get8(s);
> + z->img_comp[i].h = (q >> 4); if (!z->img_comp[i].h || z->img_comp[i].h > 4) return stbi__err("bad H","Corrupt JPEG");
> + z->img_comp[i].v = q & 15; if (!z->img_comp[i].v || z->img_comp[i].v > 4) return stbi__err("bad V","Corrupt JPEG");
> + z->img_comp[i].tq = stbi__get8(s); if (z->img_comp[i].tq > 3) return stbi__err("bad TQ","Corrupt JPEG");
> + }
> +
> + if (scan != STBI__SCAN_load) return 1;
> +
> + if (!stbi__mad3sizes_valid(s->img_x, s->img_y, s->img_n, 0)) return stbi__err("too large", "Image too large to decode");
> +
> + for (i=0; i < s->img_n; ++i) {
> + if (z->img_comp[i].h > h_max) h_max = z->img_comp[i].h;
> + if (z->img_comp[i].v > v_max) v_max = z->img_comp[i].v;
> + }
> +
> + // compute interleaved mcu info
> + z->img_h_max = h_max;
> + z->img_v_max = v_max;
> + z->img_mcu_w = h_max * 8;
> + z->img_mcu_h = v_max * 8;
> + // these sizes can't be more than 17 bits
> + z->img_mcu_x = (s->img_x + z->img_mcu_w-1) / z->img_mcu_w;
> + z->img_mcu_y = (s->img_y + z->img_mcu_h-1) / z->img_mcu_h;
> +
> + for (i=0; i < s->img_n; ++i) {
> + // number of effective pixels (e.g. for non-interleaved MCU)
> + z->img_comp[i].x = (s->img_x * z->img_comp[i].h + h_max-1) / h_max;
> + z->img_comp[i].y = (s->img_y * z->img_comp[i].v + v_max-1) / v_max;
> + // to simplify generation, we'll allocate enough memory to decode
> + // the bogus oversized data from using interleaved MCUs and their
> + // big blocks (e.g. a 16x16 iMCU on an image of width 33); we won't
> + // discard the extra data until colorspace conversion
> + //
> + // img_mcu_x, img_mcu_y: <=17 bits; comp[i].h and .v are <=4 (checked earlier)
> + // so these muls can't overflow with 32-bit ints (which we require)
> + z->img_comp[i].w2 = z->img_mcu_x * z->img_comp[i].h * 8;
> + z->img_comp[i].h2 = z->img_mcu_y * z->img_comp[i].v * 8;
> + z->img_comp[i].coeff = 0;
> + z->img_comp[i].raw_coeff = 0;
> + z->img_comp[i].linebuf = NULL;
> + z->img_comp[i].raw_data = stbi__malloc_mad2(z->img_comp[i].w2, z->img_comp[i].h2, 15);
> + if (z->img_comp[i].raw_data == NULL)
> + return stbi__free_jpeg_components(z, i+1, stbi__err("outofmem", "Out of memory"));
> + // align blocks for idct using mmx/sse
> + z->img_comp[i].data = (stbi_uc*) (((size_t) z->img_comp[i].raw_data + 15) & ~15);
> + if (z->progressive) {
> + // w2, h2 are multiples of 8 (see above)
> + z->img_comp[i].coeff_w = z->img_comp[i].w2 / 8;
> + z->img_comp[i].coeff_h = z->img_comp[i].h2 / 8;
> + z->img_comp[i].raw_coeff = stbi__malloc_mad3(z->img_comp[i].w2, z->img_comp[i].h2, sizeof(short), 15);
> + if (z->img_comp[i].raw_coeff == NULL)
> + return stbi__free_jpeg_components(z, i+1, stbi__err("outofmem", "Out of memory"));
> + z->img_comp[i].coeff = (short*) (((size_t) z->img_comp[i].raw_coeff + 15) & ~15);
> + }
> + }
> +
> + return 1;
> +}
> +
> +// use comparisons since in some cases we handle more than one case (e.g. SOF)
> +#define stbi__DNL(x) ((x) == 0xdc)
> +#define stbi__SOI(x) ((x) == 0xd8)
> +#define stbi__EOI(x) ((x) == 0xd9)
> +#define stbi__SOF(x) ((x) == 0xc0 || (x) == 0xc1 || (x) == 0xc2)
> +#define stbi__SOS(x) ((x) == 0xda)
> +
> +#define stbi__SOF_progressive(x) ((x) == 0xc2)
> +
> +static int stbi__decode_jpeg_header(stbi__jpeg *z, int scan)
> +{
> + int m;
> + z->jfif = 0;
> + z->app14_color_transform = -1; // valid values are 0,1,2
> + z->marker = STBI__MARKER_none; // initialize cached marker to empty
> + m = stbi__get_marker(z);
> + if (!stbi__SOI(m)) return stbi__err("no SOI","Corrupt JPEG");
> + if (scan == STBI__SCAN_type) return 1;
> + m = stbi__get_marker(z);
> + while (!stbi__SOF(m)) {
> + if (!stbi__process_marker(z,m)) return 0;
> + m = stbi__get_marker(z);
> + while (m == STBI__MARKER_none) {
> + // some files have extra padding after their blocks, so ok, we'll scan
> + if (stbi__at_eof(z->s)) return stbi__err("no SOF", "Corrupt JPEG");
> + m = stbi__get_marker(z);
> + }
> + }
> + z->progressive = stbi__SOF_progressive(m);
> + if (!stbi__process_frame_header(z, scan)) return 0;
> + return 1;
> +}
> +
> +// decode image to YCbCr format
> +static int stbi__decode_jpeg_image(stbi__jpeg *j)
> +{
> + int m;
> + for (m = 0; m < 4; m++) {
> + j->img_comp[m].raw_data = NULL;
> + j->img_comp[m].raw_coeff = NULL;
> + }
> + j->restart_interval = 0;
> + if (!stbi__decode_jpeg_header(j, STBI__SCAN_load)) return 0;
> + m = stbi__get_marker(j);
> + while (!stbi__EOI(m)) {
> + if (stbi__SOS(m)) {
> + if (!stbi__process_scan_header(j)) return 0;
> + if (!stbi__parse_entropy_coded_data(j)) return 0;
> + if (j->marker == STBI__MARKER_none ) {
> + // handle 0s at the end of image data from IP Kamera 9060
> + while (!stbi__at_eof(j->s)) {
> + int x = stbi__get8(j->s);
> + if (x == 255) {
> + j->marker = stbi__get8(j->s);
> + break;
> + }
> + }
> + // if we reach eof without hitting a marker, stbi__get_marker() below will fail and we'll eventually return 0
> + }
> + } else if (stbi__DNL(m)) {
> + int Ld = stbi__get16be(j->s);
> + stbi__uint32 NL = stbi__get16be(j->s);
> + if (Ld != 4) return stbi__err("bad DNL len", "Corrupt JPEG");
> + if (NL != j->s->img_y) return stbi__err("bad DNL height", "Corrupt JPEG");
> + } else {
> + if (!stbi__process_marker(j, m)) return 0;
> + }
> + m = stbi__get_marker(j);
> + }
> + if (j->progressive)
> + stbi__jpeg_finish(j);
> + return 1;
> +}
> +
> +// static jfif-centered resampling (across block boundaries)
> +
> +typedef stbi_uc *(*resample_row_func)(stbi_uc *out, stbi_uc *in0, stbi_uc *in1,
> + int w, int hs);
> +
> +#define stbi__div4(x) ((stbi_uc) ((x) >> 2))
> +
> +static stbi_uc *resample_row_1(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
> +{
> + STBI_NOTUSED(out);
> + STBI_NOTUSED(in_far);
> + STBI_NOTUSED(w);
> + STBI_NOTUSED(hs);
> + return in_near;
> +}
> +
> +static stbi_uc* stbi__resample_row_v_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
> +{
> + // need to generate two samples vertically for every one in input
> + int i;
> + STBI_NOTUSED(hs);
> + for (i=0; i < w; ++i)
> + out[i] = stbi__div4(3*in_near[i] + in_far[i] + 2);
> + return out;
> +}
> +
> +static stbi_uc* stbi__resample_row_h_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
> +{
> + // need to generate two samples horizontally for every one in input
> + int i;
> + stbi_uc *input = in_near;
> +
> + if (w == 1) {
> + // if only one sample, can't do any interpolation
> + out[0] = out[1] = input[0];
> + return out;
> + }
> +
> + out[0] = input[0];
> + out[1] = stbi__div4(input[0]*3 + input[1] + 2);
> + for (i=1; i < w-1; ++i) {
> + int n = 3*input[i]+2;
> + out[i*2+0] = stbi__div4(n+input[i-1]);
> + out[i*2+1] = stbi__div4(n+input[i+1]);
> + }
> + out[i*2+0] = stbi__div4(input[w-2]*3 + input[w-1] + 2);
> + out[i*2+1] = input[w-1];
> +
> + STBI_NOTUSED(in_far);
> + STBI_NOTUSED(hs);
> +
> + return out;
> +}
> +
> +#define stbi__div16(x) ((stbi_uc) ((x) >> 4))
> +
> +static stbi_uc *stbi__resample_row_hv_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
> +{
> + // need to generate 2x2 samples for every one in input
> + int i,t0,t1;
> + if (w == 1) {
> + out[0] = out[1] = stbi__div4(3*in_near[0] + in_far[0] + 2);
> + return out;
> + }
> +
> + t1 = 3*in_near[0] + in_far[0];
> + out[0] = stbi__div4(t1+2);
> + for (i=1; i < w; ++i) {
> + t0 = t1;
> + t1 = 3*in_near[i]+in_far[i];
> + out[i*2-1] = stbi__div16(3*t0 + t1 + 8);
> + out[i*2 ] = stbi__div16(3*t1 + t0 + 8);
> + }
> + out[w*2-1] = stbi__div4(t1+2);
> +
> + STBI_NOTUSED(hs);
> +
> + return out;
> +}
> +
> +#if defined(STBI_SSE2) || defined(STBI_NEON)
> +static stbi_uc *stbi__resample_row_hv_2_simd(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
> +{
> + // need to generate 2x2 samples for every one in input
> + int i=0,t0,t1;
> +
> + if (w == 1) {
> + out[0] = out[1] = stbi__div4(3*in_near[0] + in_far[0] + 2);
> + return out;
> + }
> +
> + t1 = 3*in_near[0] + in_far[0];
> + // process groups of 8 pixels for as long as we can.
> + // note we can't handle the last pixel in a row in this loop
> + // because we need to handle the filter boundary conditions.
> + for (; i < ((w-1) & ~7); i += 8) {
> +#if defined(STBI_SSE2)
> + // load and perform the vertical filtering pass
> + // this uses 3*x + y = 4*x + (y - x)
> + __m128i zero = _mm_setzero_si128();
> + __m128i farb = _mm_loadl_epi64((__m128i *) (in_far + i));
> + __m128i nearb = _mm_loadl_epi64((__m128i *) (in_near + i));
> + __m128i farw = _mm_unpacklo_epi8(farb, zero);
> + __m128i nearw = _mm_unpacklo_epi8(nearb, zero);
> + __m128i diff = _mm_sub_epi16(farw, nearw);
> + __m128i nears = _mm_slli_epi16(nearw, 2);
> + __m128i curr = _mm_add_epi16(nears, diff); // current row
> +
> + // horizontal filter works the same based on shifted vers of current
> + // row. "prev" is current row shifted right by 1 pixel; we need to
> + // insert the previous pixel value (from t1).
> + // "next" is current row shifted left by 1 pixel, with first pixel
> + // of next block of 8 pixels added in.
> + __m128i prv0 = _mm_slli_si128(curr, 2);
> + __m128i nxt0 = _mm_srli_si128(curr, 2);
> + __m128i prev = _mm_insert_epi16(prv0, t1, 0);
> + __m128i next = _mm_insert_epi16(nxt0, 3*in_near[i+8] + in_far[i+8], 7);
> +
> + // horizontal filter, polyphase implementation since it's convenient:
> + // even pixels = 3*cur + prev = cur*4 + (prev - cur)
> + // odd pixels = 3*cur + next = cur*4 + (next - cur)
> + // note the shared term.
> + __m128i bias = _mm_set1_epi16(8);
> + __m128i curs = _mm_slli_epi16(curr, 2);
> + __m128i prvd = _mm_sub_epi16(prev, curr);
> + __m128i nxtd = _mm_sub_epi16(next, curr);
> + __m128i curb = _mm_add_epi16(curs, bias);
> + __m128i even = _mm_add_epi16(prvd, curb);
> + __m128i odd = _mm_add_epi16(nxtd, curb);
> +
> + // interleave even and odd pixels, then undo scaling.
> + __m128i int0 = _mm_unpacklo_epi16(even, odd);
> + __m128i int1 = _mm_unpackhi_epi16(even, odd);
> + __m128i de0 = _mm_srli_epi16(int0, 4);
> + __m128i de1 = _mm_srli_epi16(int1, 4);
> +
> + // pack and write output
> + __m128i outv = _mm_packus_epi16(de0, de1);
> + _mm_storeu_si128((__m128i *) (out + i*2), outv);
> +#elif defined(STBI_NEON)
> + // load and perform the vertical filtering pass
> + // this uses 3*x + y = 4*x + (y - x)
> + uint8x8_t farb = vld1_u8(in_far + i);
> + uint8x8_t nearb = vld1_u8(in_near + i);
> + int16x8_t diff = vreinterpretq_s16_u16(vsubl_u8(farb, nearb));
> + int16x8_t nears = vreinterpretq_s16_u16(vshll_n_u8(nearb, 2));
> + int16x8_t curr = vaddq_s16(nears, diff); // current row
> +
> + // horizontal filter works the same based on shifted vers of current
> + // row. "prev" is current row shifted right by 1 pixel; we need to
> + // insert the previous pixel value (from t1).
> + // "next" is current row shifted left by 1 pixel, with first pixel
> + // of next block of 8 pixels added in.
> + int16x8_t prv0 = vextq_s16(curr, curr, 7);
> + int16x8_t nxt0 = vextq_s16(curr, curr, 1);
> + int16x8_t prev = vsetq_lane_s16(t1, prv0, 0);
> + int16x8_t next = vsetq_lane_s16(3*in_near[i+8] + in_far[i+8], nxt0, 7);
> +
> + // horizontal filter, polyphase implementation since it's convenient:
> + // even pixels = 3*cur + prev = cur*4 + (prev - cur)
> + // odd pixels = 3*cur + next = cur*4 + (next - cur)
> + // note the shared term.
> + int16x8_t curs = vshlq_n_s16(curr, 2);
> + int16x8_t prvd = vsubq_s16(prev, curr);
> + int16x8_t nxtd = vsubq_s16(next, curr);
> + int16x8_t even = vaddq_s16(curs, prvd);
> + int16x8_t odd = vaddq_s16(curs, nxtd);
> +
> + // undo scaling and round, then store with even/odd phases interleaved
> + uint8x8x2_t o;
> + o.val[0] = vqrshrun_n_s16(even, 4);
> + o.val[1] = vqrshrun_n_s16(odd, 4);
> + vst2_u8(out + i*2, o);
> +#endif
> +
> + // "previous" value for next iter
> + t1 = 3*in_near[i+7] + in_far[i+7];
> + }
> +
> + t0 = t1;
> + t1 = 3*in_near[i] + in_far[i];
> + out[i*2] = stbi__div16(3*t1 + t0 + 8);
> +
> + for (++i; i < w; ++i) {
> + t0 = t1;
> + t1 = 3*in_near[i]+in_far[i];
> + out[i*2-1] = stbi__div16(3*t0 + t1 + 8);
> + out[i*2 ] = stbi__div16(3*t1 + t0 + 8);
> + }
> + out[w*2-1] = stbi__div4(t1+2);
> +
> + STBI_NOTUSED(hs);
> +
> + return out;
> +}
> +#endif
> +
> +static stbi_uc *stbi__resample_row_generic(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
> +{
> + // resample with nearest-neighbor
> + int i,j;
> + STBI_NOTUSED(in_far);
> + for (i=0; i < w; ++i)
> + for (j=0; j < hs; ++j)
> + out[i*hs+j] = in_near[i];
> + return out;
> +}
> +
> +// this is a reduced-precision calculation of YCbCr-to-RGB introduced
> +// to make sure the code produces the same results in both SIMD and scalar
> +#define stbi__float2fixed(x) (((int) ((x) * 4096.0f + 0.5f)) << 8)
> +static void stbi__YCbCr_to_RGB_row(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step)
> +{
> + int i;
> + for (i=0; i < count; ++i) {
> + int y_fixed = (y[i] << 20) + (1<<19); // rounding
> + int r,g,b;
> + int cr = pcr[i] - 128;
> + int cb = pcb[i] - 128;
> + r = y_fixed + cr* stbi__float2fixed(1.40200f);
> + g = y_fixed + (cr*-stbi__float2fixed(0.71414f)) + ((cb*-stbi__float2fixed(0.34414f)) & 0xffff0000);
> + b = y_fixed + cb* stbi__float2fixed(1.77200f);
> + r >>= 20;
> + g >>= 20;
> + b >>= 20;
> + if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; }
> + if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; }
> + if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; }
> + out[0] = (stbi_uc)r;
> + out[1] = (stbi_uc)g;
> + out[2] = (stbi_uc)b;
> + out[3] = 255;
> + out += step;
> + }
> +}
> +
> +#if defined(STBI_SSE2) || defined(STBI_NEON)
> +static void stbi__YCbCr_to_RGB_simd(stbi_uc *out, stbi_uc const *y, stbi_uc const *pcb, stbi_uc const *pcr, int count, int step)
> +{
> + int i = 0;
> +
> +#ifdef STBI_SSE2
> + // step == 3 is pretty ugly on the final interleave, and i'm not convinced
> + // it's useful in practice (you wouldn't use it for textures, for example).
> + // so just accelerate step == 4 case.
> + if (step == 4) {
> + // this is a fairly straightforward implementation and not super-optimized.
> + __m128i signflip = _mm_set1_epi8(-0x80);
> + __m128i cr_const0 = _mm_set1_epi16( (short) ( 1.40200f*4096.0f+0.5f));
> + __m128i cr_const1 = _mm_set1_epi16( - (short) ( 0.71414f*4096.0f+0.5f));
> + __m128i cb_const0 = _mm_set1_epi16( - (short) ( 0.34414f*4096.0f+0.5f));
> + __m128i cb_const1 = _mm_set1_epi16( (short) ( 1.77200f*4096.0f+0.5f));
> + __m128i y_bias = _mm_set1_epi8((char) (unsigned char) 128);
> + __m128i xw = _mm_set1_epi16(255); // alpha channel
> +
> + for (; i+7 < count; i += 8) {
> + // load
> + __m128i y_bytes = _mm_loadl_epi64((__m128i *) (y+i));
> + __m128i cr_bytes = _mm_loadl_epi64((__m128i *) (pcr+i));
> + __m128i cb_bytes = _mm_loadl_epi64((__m128i *) (pcb+i));
> + __m128i cr_biased = _mm_xor_si128(cr_bytes, signflip); // -128
> + __m128i cb_biased = _mm_xor_si128(cb_bytes, signflip); // -128
> +
> + // unpack to short (and left-shift cr, cb by 8)
> + __m128i yw = _mm_unpacklo_epi8(y_bias, y_bytes);
> + __m128i crw = _mm_unpacklo_epi8(_mm_setzero_si128(), cr_biased);
> + __m128i cbw = _mm_unpacklo_epi8(_mm_setzero_si128(), cb_biased);
> +
> + // color transform
> + __m128i yws = _mm_srli_epi16(yw, 4);
> + __m128i cr0 = _mm_mulhi_epi16(cr_const0, crw);
> + __m128i cb0 = _mm_mulhi_epi16(cb_const0, cbw);
> + __m128i cb1 = _mm_mulhi_epi16(cbw, cb_const1);
> + __m128i cr1 = _mm_mulhi_epi16(crw, cr_const1);
> + __m128i rws = _mm_add_epi16(cr0, yws);
> + __m128i gwt = _mm_add_epi16(cb0, yws);
> + __m128i bws = _mm_add_epi16(yws, cb1);
> + __m128i gws = _mm_add_epi16(gwt, cr1);
> +
> + // descale
> + __m128i rw = _mm_srai_epi16(rws, 4);
> + __m128i bw = _mm_srai_epi16(bws, 4);
> + __m128i gw = _mm_srai_epi16(gws, 4);
> +
> + // back to byte, set up for transpose
> + __m128i brb = _mm_packus_epi16(rw, bw);
> + __m128i gxb = _mm_packus_epi16(gw, xw);
> +
> + // transpose to interleave channels
> + __m128i t0 = _mm_unpacklo_epi8(brb, gxb);
> + __m128i t1 = _mm_unpackhi_epi8(brb, gxb);
> + __m128i o0 = _mm_unpacklo_epi16(t0, t1);
> + __m128i o1 = _mm_unpackhi_epi16(t0, t1);
> +
> + // store
> + _mm_storeu_si128((__m128i *) (out + 0), o0);
> + _mm_storeu_si128((__m128i *) (out + 16), o1);
> + out += 32;
> + }
> + }
> +#endif
> +
> +#ifdef STBI_NEON
> + // in this version, step=3 support would be easy to add. but is there demand?
> + if (step == 4) {
> + // this is a fairly straightforward implementation and not super-optimized.
> + uint8x8_t signflip = vdup_n_u8(0x80);
> + int16x8_t cr_const0 = vdupq_n_s16( (short) ( 1.40200f*4096.0f+0.5f));
> + int16x8_t cr_const1 = vdupq_n_s16( - (short) ( 0.71414f*4096.0f+0.5f));
> + int16x8_t cb_const0 = vdupq_n_s16( - (short) ( 0.34414f*4096.0f+0.5f));
> + int16x8_t cb_const1 = vdupq_n_s16( (short) ( 1.77200f*4096.0f+0.5f));
> +
> + for (; i+7 < count; i += 8) {
> + // load
> + uint8x8_t y_bytes = vld1_u8(y + i);
> + uint8x8_t cr_bytes = vld1_u8(pcr + i);
> + uint8x8_t cb_bytes = vld1_u8(pcb + i);
> + int8x8_t cr_biased = vreinterpret_s8_u8(vsub_u8(cr_bytes, signflip));
> + int8x8_t cb_biased = vreinterpret_s8_u8(vsub_u8(cb_bytes, signflip));
> +
> + // expand to s16
> + int16x8_t yws = vreinterpretq_s16_u16(vshll_n_u8(y_bytes, 4));
> + int16x8_t crw = vshll_n_s8(cr_biased, 7);
> + int16x8_t cbw = vshll_n_s8(cb_biased, 7);
> +
> + // color transform
> + int16x8_t cr0 = vqdmulhq_s16(crw, cr_const0);
> + int16x8_t cb0 = vqdmulhq_s16(cbw, cb_const0);
> + int16x8_t cr1 = vqdmulhq_s16(crw, cr_const1);
> + int16x8_t cb1 = vqdmulhq_s16(cbw, cb_const1);
> + int16x8_t rws = vaddq_s16(yws, cr0);
> + int16x8_t gws = vaddq_s16(vaddq_s16(yws, cb0), cr1);
> + int16x8_t bws = vaddq_s16(yws, cb1);
> +
> + // undo scaling, round, convert to byte
> + uint8x8x4_t o;
> + o.val[0] = vqrshrun_n_s16(rws, 4);
> + o.val[1] = vqrshrun_n_s16(gws, 4);
> + o.val[2] = vqrshrun_n_s16(bws, 4);
> + o.val[3] = vdup_n_u8(255);
> +
> + // store, interleaving r/g/b/a
> + vst4_u8(out, o);
> + out += 8*4;
> + }
> + }
> +#endif
> +
> + for (; i < count; ++i) {
> + int y_fixed = (y[i] << 20) + (1<<19); // rounding
> + int r,g,b;
> + int cr = pcr[i] - 128;
> + int cb = pcb[i] - 128;
> + r = y_fixed + cr* stbi__float2fixed(1.40200f);
> + g = y_fixed + cr*-stbi__float2fixed(0.71414f) + ((cb*-stbi__float2fixed(0.34414f)) & 0xffff0000);
> + b = y_fixed + cb* stbi__float2fixed(1.77200f);
> + r >>= 20;
> + g >>= 20;
> + b >>= 20;
> + if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; }
> + if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; }
> + if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; }
> + out[0] = (stbi_uc)r;
> + out[1] = (stbi_uc)g;
> + out[2] = (stbi_uc)b;
> + out[3] = 255;
> + out += step;
> + }
> +}
> +#endif
> +
> +// set up the kernels
> +static void stbi__setup_jpeg(stbi__jpeg *j)
> +{
> + j->idct_block_kernel = stbi__idct_block;
> + j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_row;
> + j->resample_row_hv_2_kernel = stbi__resample_row_hv_2;
> +
> +#ifdef STBI_SSE2
> + if (stbi__sse2_available()) {
> + j->idct_block_kernel = stbi__idct_simd;
> + j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd;
> + j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd;
> + }
> +#endif
> +
> +#ifdef STBI_NEON
> + j->idct_block_kernel = stbi__idct_simd;
> + j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd;
> + j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd;
> +#endif
> +}
> +
> +// clean up the temporary component buffers
> +static void stbi__cleanup_jpeg(stbi__jpeg *j)
> +{
> + stbi__free_jpeg_components(j, j->s->img_n, 0);
> +}
> +
> +typedef struct
> +{
> + resample_row_func resample;
> + stbi_uc *line0,*line1;
> + int hs,vs; // expansion factor in each axis
> + int w_lores; // horizontal pixels pre-expansion
> + int ystep; // how far through vertical expansion we are
> + int ypos; // which pre-expansion row we're on
> +} stbi__resample;
> +
> +// fast 0..255 * 0..255 => 0..255 rounded multiplication
> +static stbi_uc stbi__blinn_8x8(stbi_uc x, stbi_uc y)
> +{
> + unsigned int t = x*y + 128;
> + return (stbi_uc) ((t + (t >>8)) >> 8);
> +}
> +
> +static stbi_uc *load_jpeg_image(stbi__jpeg *z, int *out_x, int *out_y, int *comp, int req_comp)
> +{
> + int n, decode_n, is_rgb;
> + z->s->img_n = 0; // make stbi__cleanup_jpeg safe
> +
> + // validate req_comp
> + if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error");
> +
> + // load a jpeg image from whichever source, but leave in YCbCr format
> + if (!stbi__decode_jpeg_image(z)) { stbi__cleanup_jpeg(z); return NULL; }
> +
> + // determine actual number of components to generate
> + n = req_comp ? req_comp : z->s->img_n >= 3 ? 3 : 1;
> +
> + is_rgb = z->s->img_n == 3 && (z->rgb == 3 || (z->app14_color_transform == 0 && !z->jfif));
> +
> + if (z->s->img_n == 3 && n < 3 && !is_rgb)
> + decode_n = 1;
> + else
> + decode_n = z->s->img_n;
> +
> + // resample and color-convert
> + {
> + int k;
> + unsigned int i,j;
> + stbi_uc *output;
> + stbi_uc *coutput[4] = { NULL, NULL, NULL, NULL };
> +
> + stbi__resample res_comp[4];
> +
> + for (k=0; k < decode_n; ++k) {
> + stbi__resample *r = &res_comp[k];
> +
> + // allocate line buffer big enough for upsampling off the edges
> + // with upsample factor of 4
> + z->img_comp[k].linebuf = (stbi_uc *) stbi__malloc(z->s->img_x + 3);
> + if (!z->img_comp[k].linebuf) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); }
> +
> + r->hs = z->img_h_max / z->img_comp[k].h;
> + r->vs = z->img_v_max / z->img_comp[k].v;
> + r->ystep = r->vs >> 1;
> + r->w_lores = (z->s->img_x + r->hs-1) / r->hs;
> + r->ypos = 0;
> + r->line0 = r->line1 = z->img_comp[k].data;
> +
> + if (r->hs == 1 && r->vs == 1) r->resample = resample_row_1;
> + else if (r->hs == 1 && r->vs == 2) r->resample = stbi__resample_row_v_2;
> + else if (r->hs == 2 && r->vs == 1) r->resample = stbi__resample_row_h_2;
> + else if (r->hs == 2 && r->vs == 2) r->resample = z->resample_row_hv_2_kernel;
> + else r->resample = stbi__resample_row_generic;
> + }
> +
> + // can't error after this so, this is safe
> + output = (stbi_uc *) stbi__malloc_mad3(n, z->s->img_x, z->s->img_y, 1);
> + if (!output) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); }
> +
> + // now go ahead and resample
> + for (j=0; j < z->s->img_y; ++j) {
> + stbi_uc *out = output + n * z->s->img_x * j;
> + for (k=0; k < decode_n; ++k) {
> + stbi__resample *r = &res_comp[k];
> + int y_bot = r->ystep >= (r->vs >> 1);
> + coutput[k] = r->resample(z->img_comp[k].linebuf,
> + y_bot ? r->line1 : r->line0,
> + y_bot ? r->line0 : r->line1,
> + r->w_lores, r->hs);
> + if (++r->ystep >= r->vs) {
> + r->ystep = 0;
> + r->line0 = r->line1;
> + if (++r->ypos < z->img_comp[k].y)
> + r->line1 += z->img_comp[k].w2;
> + }
> + }
> + if (n >= 3) {
> + stbi_uc *y = coutput[0];
> + if (z->s->img_n == 3) {
> + if (is_rgb) {
> + for (i=0; i < z->s->img_x; ++i) {
> + out[0] = y[i];
> + out[1] = coutput[1][i];
> + out[2] = coutput[2][i];
> + out[3] = 255;
> + out += n;
> + }
> + } else {
> + z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n);
> + }
> + } else if (z->s->img_n == 4) {
> + if (z->app14_color_transform == 0) { // CMYK
> + for (i=0; i < z->s->img_x; ++i) {
> + stbi_uc m = coutput[3][i];
> + out[0] = stbi__blinn_8x8(coutput[0][i], m);
> + out[1] = stbi__blinn_8x8(coutput[1][i], m);
> + out[2] = stbi__blinn_8x8(coutput[2][i], m);
> + out[3] = 255;
> + out += n;
> + }
> + } else if (z->app14_color_transform == 2) { // YCCK
> + z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n);
> + for (i=0; i < z->s->img_x; ++i) {
> + stbi_uc m = coutput[3][i];
> + out[0] = stbi__blinn_8x8(255 - out[0], m);
> + out[1] = stbi__blinn_8x8(255 - out[1], m);
> + out[2] = stbi__blinn_8x8(255 - out[2], m);
> + out += n;
> + }
> + } else { // YCbCr + alpha? Ignore the fourth channel for now
> + z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n);
> + }
> + } else
> + for (i=0; i < z->s->img_x; ++i) {
> + out[0] = out[1] = out[2] = y[i];
> + out[3] = 255; // not used if n==3
> + out += n;
> + }
> + } else {
> + if (is_rgb) {
> + if (n == 1)
> + for (i=0; i < z->s->img_x; ++i)
> + *out++ = stbi__compute_y(coutput[0][i], coutput[1][i], coutput[2][i]);
> + else {
> + for (i=0; i < z->s->img_x; ++i, out += 2) {
> + out[0] = stbi__compute_y(coutput[0][i], coutput[1][i], coutput[2][i]);
> + out[1] = 255;
> + }
> + }
> + } else if (z->s->img_n == 4 && z->app14_color_transform == 0) {
> + for (i=0; i < z->s->img_x; ++i) {
> + stbi_uc m = coutput[3][i];
> + stbi_uc r = stbi__blinn_8x8(coutput[0][i], m);
> + stbi_uc g = stbi__blinn_8x8(coutput[1][i], m);
> + stbi_uc b = stbi__blinn_8x8(coutput[2][i], m);
> + out[0] = stbi__compute_y(r, g, b);
> + out[1] = 255;
> + out += n;
> + }
> + } else if (z->s->img_n == 4 && z->app14_color_transform == 2) {
> + for (i=0; i < z->s->img_x; ++i) {
> + out[0] = stbi__blinn_8x8(255 - coutput[0][i], coutput[3][i]);
> + out[1] = 255;
> + out += n;
> + }
> + } else {
> + stbi_uc *y = coutput[0];
> + if (n == 1)
> + for (i=0; i < z->s->img_x; ++i) out[i] = y[i];
> + else
> + for (i=0; i < z->s->img_x; ++i) { *out++ = y[i]; *out++ = 255; }
> + }
> + }
> + }
> + stbi__cleanup_jpeg(z);
> + *out_x = z->s->img_x;
> + *out_y = z->s->img_y;
> + if (comp) *comp = z->s->img_n >= 3 ? 3 : 1; // report original components, not output
> + return output;
> + }
> +}
> +
> +static void *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
> +{
> + unsigned char* result;
> + stbi__jpeg* j = (stbi__jpeg*) stbi__malloc(sizeof(stbi__jpeg));
> + STBI_NOTUSED(ri);
> + j->s = s;
> + stbi__setup_jpeg(j);
> + result = load_jpeg_image(j, x,y,comp,req_comp);
> + STBI_FREE(j);
> + return result;
> +}
> +
> +static int stbi__jpeg_test(stbi__context *s)
> +{
> + int r;
> + stbi__jpeg* j = (stbi__jpeg*)stbi__malloc(sizeof(stbi__jpeg));
> + j->s = s;
> + stbi__setup_jpeg(j);
> + r = stbi__decode_jpeg_header(j, STBI__SCAN_type);
> + stbi__rewind(s);
> + STBI_FREE(j);
> + return r;
> +}
> +
> +static int stbi__jpeg_info_raw(stbi__jpeg *j, int *x, int *y, int *comp)
> +{
> + if (!stbi__decode_jpeg_header(j, STBI__SCAN_header)) {
> + stbi__rewind( j->s );
> + return 0;
> + }
> + if (x) *x = j->s->img_x;
> + if (y) *y = j->s->img_y;
> + if (comp) *comp = j->s->img_n >= 3 ? 3 : 1;
> + return 1;
> +}
> +
> +static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + int result;
> + stbi__jpeg* j = (stbi__jpeg*) (stbi__malloc(sizeof(stbi__jpeg)));
> + j->s = s;
> + result = stbi__jpeg_info_raw(j, x, y, comp);
> + STBI_FREE(j);
> + return result;
> +}
> +#endif
> +
> +// public domain zlib decode v0.2 Sean Barrett 2006-11-18
> +// simple implementation
> +// - all input must be provided in an upfront buffer
> +// - all output is written to a single output buffer (can malloc/realloc)
> +// performance
> +// - fast huffman
> +
> +#ifndef STBI_NO_ZLIB
> +
> +// fast-way is faster to check than jpeg huffman, but slow way is slower
> +#define STBI__ZFAST_BITS 9 // accelerate all cases in default tables
> +#define STBI__ZFAST_MASK ((1 << STBI__ZFAST_BITS) - 1)
> +
> +// zlib-style huffman encoding
> +// (jpegs packs from left, zlib from right, so can't share code)
> +typedef struct
> +{
> + stbi__uint16 fast[1 << STBI__ZFAST_BITS];
> + stbi__uint16 firstcode[16];
> + int maxcode[17];
> + stbi__uint16 firstsymbol[16];
> + stbi_uc size[288];
> + stbi__uint16 value[288];
> +} stbi__zhuffman;
> +
> +stbi_inline static int stbi__bitreverse16(int n)
> +{
> + n = ((n & 0xAAAA) >> 1) | ((n & 0x5555) << 1);
> + n = ((n & 0xCCCC) >> 2) | ((n & 0x3333) << 2);
> + n = ((n & 0xF0F0) >> 4) | ((n & 0x0F0F) << 4);
> + n = ((n & 0xFF00) >> 8) | ((n & 0x00FF) << 8);
> + return n;
> +}
> +
> +stbi_inline static int stbi__bit_reverse(int v, int bits)
> +{
> + STBI_ASSERT(bits <= 16);
> + // to bit reverse n bits, reverse 16 and shift
> + // e.g. 11 bits, bit reverse and shift away 5
> + return stbi__bitreverse16(v) >> (16-bits);
> +}
> +
> +static int stbi__zbuild_huffman(stbi__zhuffman *z, const stbi_uc *sizelist, int num)
> +{
> + int i,k=0;
> + int code, next_code[16], sizes[17];
> +
> + // DEFLATE spec for generating codes
> + memset(sizes, 0, sizeof(sizes));
> + memset(z->fast, 0, sizeof(z->fast));
> + for (i=0; i < num; ++i)
> + ++sizes[sizelist[i]];
> + sizes[0] = 0;
> + for (i=1; i < 16; ++i)
> + if (sizes[i] > (1 << i))
> + return stbi__err("bad sizes", "Corrupt PNG");
> + code = 0;
> + for (i=1; i < 16; ++i) {
> + next_code[i] = code;
> + z->firstcode[i] = (stbi__uint16) code;
> + z->firstsymbol[i] = (stbi__uint16) k;
> + code = (code + sizes[i]);
> + if (sizes[i])
> + if (code-1 >= (1 << i)) return stbi__err("bad codelengths","Corrupt PNG");
> + z->maxcode[i] = code << (16-i); // preshift for inner loop
> + code <<= 1;
> + k += sizes[i];
> + }
> + z->maxcode[16] = 0x10000; // sentinel
> + for (i=0; i < num; ++i) {
> + int s = sizelist[i];
> + if (s) {
> + int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s];
> + stbi__uint16 fastv = (stbi__uint16) ((s << 9) | i);
> + z->size [c] = (stbi_uc ) s;
> + z->value[c] = (stbi__uint16) i;
> + if (s <= STBI__ZFAST_BITS) {
> + int j = stbi__bit_reverse(next_code[s],s);
> + while (j < (1 << STBI__ZFAST_BITS)) {
> + z->fast[j] = fastv;
> + j += (1 << s);
> + }
> + }
> + ++next_code[s];
> + }
> + }
> + return 1;
> +}
> +
> +// zlib-from-memory implementation for PNG reading
> +// because PNG allows splitting the zlib stream arbitrarily,
> +// and it's annoying structurally to have PNG call ZLIB call PNG,
> +// we require PNG read all the IDATs and combine them into a single
> +// memory buffer
> +
> +typedef struct
> +{
> + stbi_uc *zbuffer, *zbuffer_end;
> + int num_bits;
> + stbi__uint32 code_buffer;
> +
> + char *zout;
> + char *zout_start;
> + char *zout_end;
> + int z_expandable;
> +
> + stbi__zhuffman z_length, z_distance;
> +} stbi__zbuf;
> +
> +stbi_inline static int stbi__zeof(stbi__zbuf *z)
> +{
> + return (z->zbuffer >= z->zbuffer_end);
> +}
> +
> +stbi_inline static stbi_uc stbi__zget8(stbi__zbuf *z)
> +{
> + return stbi__zeof(z) ? 0 : *z->zbuffer++;
> +}
> +
> +static void stbi__fill_bits(stbi__zbuf *z)
> +{
> + do {
> + if (z->code_buffer >= (1U << z->num_bits)) {
> + z->zbuffer = z->zbuffer_end; /* treat this as EOF so we fail. */
> + return;
> + }
> + z->code_buffer |= (unsigned int) stbi__zget8(z) << z->num_bits;
> + z->num_bits += 8;
> + } while (z->num_bits <= 24);
> +}
> +
> +stbi_inline static unsigned int stbi__zreceive(stbi__zbuf *z, int n)
> +{
> + unsigned int k;
> + if (z->num_bits < n) stbi__fill_bits(z);
> + k = z->code_buffer & ((1 << n) - 1);
> + z->code_buffer >>= n;
> + z->num_bits -= n;
> + return k;
> +}
> +
> +static int stbi__zhuffman_decode_slowpath(stbi__zbuf *a, stbi__zhuffman *z)
> +{
> + int b,s,k;
> + // not resolved by fast table, so compute it the slow way
> + // use jpeg approach, which requires MSbits at top
> + k = stbi__bit_reverse(a->code_buffer, 16);
> + for (s=STBI__ZFAST_BITS+1; ; ++s)
> + if (k < z->maxcode[s])
> + break;
> + if (s >= 16) return -1; // invalid code!
> + // code size is s, so:
> + b = (k >> (16-s)) - z->firstcode[s] + z->firstsymbol[s];
> + if ((long unsigned int) b >= sizeof (z->size)) return -1; // some data was corrupt somewhere!
> + if (z->size[b] != s) return -1; // was originally an assert, but report failure instead.
> + a->code_buffer >>= s;
> + a->num_bits -= s;
> + return z->value[b];
> +}
> +
> +stbi_inline static int stbi__zhuffman_decode(stbi__zbuf *a, stbi__zhuffman *z)
> +{
> + int b,s;
> + if (a->num_bits < 16) {
> + if (stbi__zeof(a)) {
> + return -1; /* report error for unexpected end of data. */
> + }
> + stbi__fill_bits(a);
> + }
> + b = z->fast[a->code_buffer & STBI__ZFAST_MASK];
> + if (b) {
> + s = b >> 9;
> + a->code_buffer >>= s;
> + a->num_bits -= s;
> + return b & 511;
> + }
> + return stbi__zhuffman_decode_slowpath(a, z);
> +}
> +
> +static int stbi__zexpand(stbi__zbuf *z, char *zout, int n) // need to make room for n bytes
> +{
> + char *q;
> + unsigned int cur, limit, old_limit;
> + z->zout = zout;
> + if (!z->z_expandable) return stbi__err("output buffer limit","Corrupt PNG");
> + cur = (unsigned int) (z->zout - z->zout_start);
> + limit = old_limit = (unsigned) (z->zout_end - z->zout_start);
> + if (UINT_MAX - cur < (unsigned) n) return stbi__err("outofmem", "Out of memory");
> + while (cur + n > limit) {
> + if(limit > UINT_MAX / 2) return stbi__err("outofmem", "Out of memory");
> + limit *= 2;
> + }
> + q = (char *) STBI_REALLOC_SIZED(z->zout_start, old_limit, limit);
> + STBI_NOTUSED(old_limit);
> + if (q == NULL) return stbi__err("outofmem", "Out of memory");
> + z->zout_start = q;
> + z->zout = q + cur;
> + z->zout_end = q + limit;
> + return 1;
> +}
> +
> +static const int stbi__zlength_base[31] = {
> + 3,4,5,6,7,8,9,10,11,13,
> + 15,17,19,23,27,31,35,43,51,59,
> + 67,83,99,115,131,163,195,227,258,0,0 };
> +
> +static const int stbi__zlength_extra[31]=
> +{ 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 };
> +
> +static const int stbi__zdist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,
> +257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0};
> +
> +static const int stbi__zdist_extra[32] =
> +{ 0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
> +
> +static int stbi__parse_huffman_block(stbi__zbuf *a)
> +{
> + char *zout = a->zout;
> + for(;;) {
> + int z = stbi__zhuffman_decode(a, &a->z_length);
> + if (z < 256) {
> + if (z < 0) return stbi__err("bad huffman code","Corrupt PNG"); // error in huffman codes
> + if (zout >= a->zout_end) {
> + if (!stbi__zexpand(a, zout, 1)) return 0;
> + zout = a->zout;
> + }
> + *zout++ = (char) z;
> + } else {
> + stbi_uc *p;
> + int len,dist;
> + if (z == 256) {
> + a->zout = zout;
> + return 1;
> + }
> + z -= 257;
> + len = stbi__zlength_base[z];
> + if (stbi__zlength_extra[z]) len += stbi__zreceive(a, stbi__zlength_extra[z]);
> + z = stbi__zhuffman_decode(a, &a->z_distance);
> + if (z < 0) return stbi__err("bad huffman code","Corrupt PNG");
> + dist = stbi__zdist_base[z];
> + if (stbi__zdist_extra[z]) dist += stbi__zreceive(a, stbi__zdist_extra[z]);
> + if (zout - a->zout_start < dist) return stbi__err("bad dist","Corrupt PNG");
> + if (zout + len > a->zout_end) {
> + if (!stbi__zexpand(a, zout, len)) return 0;
> + zout = a->zout;
> + }
> + p = (stbi_uc *) (zout - dist);
> + if (dist == 1) { // run of one byte; common in images.
> + stbi_uc v = *p;
> + if (len) { do *zout++ = v; while (--len); }
> + } else {
> + if (len) { do *zout++ = *p++; while (--len); }
> + }
> + }
> + }
> +}
> +
> +static int stbi__compute_huffman_codes(stbi__zbuf *a)
> +{
> + static const stbi_uc length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 };
> + stbi__zhuffman z_codelength;
> + stbi_uc lencodes[286+32+137];//padding for maximum single op
> + stbi_uc codelength_sizes[19];
> + int i,n;
> +
> + int hlit = stbi__zreceive(a,5) + 257;
> + int hdist = stbi__zreceive(a,5) + 1;
> + int hclen = stbi__zreceive(a,4) + 4;
> + int ntot = hlit + hdist;
> +
> + memset(codelength_sizes, 0, sizeof(codelength_sizes));
> + for (i=0; i < hclen; ++i) {
> + int s = stbi__zreceive(a,3);
> + codelength_sizes[length_dezigzag[i]] = (stbi_uc) s;
> + }
> + if (!stbi__zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0;
> +
> + n = 0;
> + while (n < ntot) {
> + int c = stbi__zhuffman_decode(a, &z_codelength);
> + if (c < 0 || c >= 19) return stbi__err("bad codelengths", "Corrupt PNG");
> + if (c < 16)
> + lencodes[n++] = (stbi_uc) c;
> + else {
> + stbi_uc fill = 0;
> + if (c == 16) {
> + c = stbi__zreceive(a,2)+3;
> + if (n == 0) return stbi__err("bad codelengths", "Corrupt PNG");
> + fill = lencodes[n-1];
> + } else if (c == 17) {
> + c = stbi__zreceive(a,3)+3;
> + } else if (c == 18) {
> + c = stbi__zreceive(a,7)+11;
> + } else {
> + return stbi__err("bad codelengths", "Corrupt PNG");
> + }
> + if (ntot - n < c) return stbi__err("bad codelengths", "Corrupt PNG");
> + memset(lencodes+n, fill, c);
> + n += c;
> + }
> + }
> + if (n != ntot) return stbi__err("bad codelengths","Corrupt PNG");
> + if (!stbi__zbuild_huffman(&a->z_length, lencodes, hlit)) return 0;
> + if (!stbi__zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0;
> + return 1;
> +}
> +
> +static int stbi__parse_uncompressed_block(stbi__zbuf *a)
> +{
> + stbi_uc header[4];
> + int len,nlen,k;
> + if (a->num_bits & 7)
> + stbi__zreceive(a, a->num_bits & 7); // discard
> + // drain the bit-packed data into header
> + k = 0;
> + while (a->num_bits > 0) {
> + header[k++] = (stbi_uc) (a->code_buffer & 255); // suppress MSVC run-time check
> + a->code_buffer >>= 8;
> + a->num_bits -= 8;
> + }
> + if (a->num_bits < 0) return stbi__err("zlib corrupt","Corrupt PNG");
> + // now fill header the normal way
> + while (k < 4)
> + header[k++] = stbi__zget8(a);
> + len = header[1] * 256 + header[0];
> + nlen = header[3] * 256 + header[2];
> + if (nlen != (len ^ 0xffff)) return stbi__err("zlib corrupt","Corrupt PNG");
> + if (a->zbuffer + len > a->zbuffer_end) return stbi__err("read past buffer","Corrupt PNG");
> + if (a->zout + len > a->zout_end)
> + if (!stbi__zexpand(a, a->zout, len)) return 0;
> + memcpy(a->zout, a->zbuffer, len);
> + a->zbuffer += len;
> + a->zout += len;
> + return 1;
> +}
> +
> +static int stbi__parse_zlib_header(stbi__zbuf *a)
> +{
> + int cmf = stbi__zget8(a);
> + int cm = cmf & 15;
> + /* int cinfo = cmf >> 4; */
> + int flg = stbi__zget8(a);
> + if (stbi__zeof(a)) return stbi__err("bad zlib header","Corrupt PNG"); // zlib spec
> + if ((cmf*256+flg) % 31 != 0) return stbi__err("bad zlib header","Corrupt PNG"); // zlib spec
> + if (flg & 32) return stbi__err("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png
> + if (cm != 8) return stbi__err("bad compression","Corrupt PNG"); // DEFLATE required for png
> + // window = 1 << (8 + cinfo)... but who cares, we fully buffer output
> + return 1;
> +}
> +
> +static const stbi_uc stbi__zdefault_length[288] =
> +{
> + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
> + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
> + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
> + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
> + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
> + 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
> + 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
> + 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
> + 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8
> +};
> +static const stbi_uc stbi__zdefault_distance[32] =
> +{
> + 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5
> +};
> +/*
> +Init algorithm:
> +{
> + int i; // use <= to match clearly with spec
> + for (i=0; i <= 143; ++i) stbi__zdefault_length[i] = 8;
> + for ( ; i <= 255; ++i) stbi__zdefault_length[i] = 9;
> + for ( ; i <= 279; ++i) stbi__zdefault_length[i] = 7;
> + for ( ; i <= 287; ++i) stbi__zdefault_length[i] = 8;
> +
> + for (i=0; i <= 31; ++i) stbi__zdefault_distance[i] = 5;
> +}
> +*/
> +
> +static int stbi__parse_zlib(stbi__zbuf *a, int parse_header)
> +{
> + int final, type;
> + if (parse_header)
> + if (!stbi__parse_zlib_header(a)) return 0;
> + a->num_bits = 0;
> + a->code_buffer = 0;
> + do {
> + final = stbi__zreceive(a,1);
> + type = stbi__zreceive(a,2);
> + if (type == 0) {
> + if (!stbi__parse_uncompressed_block(a)) return 0;
> + } else if (type == 3) {
> + return 0;
> + } else {
> + if (type == 1) {
> + // use fixed code lengths
> + if (!stbi__zbuild_huffman(&a->z_length , stbi__zdefault_length , 288)) return 0;
> + if (!stbi__zbuild_huffman(&a->z_distance, stbi__zdefault_distance, 32)) return 0;
> + } else {
> + if (!stbi__compute_huffman_codes(a)) return 0;
> + }
> + if (!stbi__parse_huffman_block(a)) return 0;
> + }
> + } while (!final);
> + return 1;
> +}
> +
> +static int stbi__do_zlib(stbi__zbuf *a, char *obuf, int olen, int exp, int parse_header)
> +{
> + a->zout_start = obuf;
> + a->zout = obuf;
> + a->zout_end = obuf + olen;
> + a->z_expandable = exp;
> +
> + return stbi__parse_zlib(a, parse_header);
> +}
> +
> +STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen)
> +{
> + stbi__zbuf a;
> + char *p = (char *) stbi__malloc(initial_size);
> + if (p == NULL) return NULL;
> + a.zbuffer = (stbi_uc *) buffer;
> + a.zbuffer_end = (stbi_uc *) buffer + len;
> + if (stbi__do_zlib(&a, p, initial_size, 1, 1)) {
> + if (outlen) *outlen = (int) (a.zout - a.zout_start);
> + return a.zout_start;
> + } else {
> + STBI_FREE(a.zout_start);
> + return NULL;
> + }
> +}
> +
> +STBIDEF char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen)
> +{
> + return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen);
> +}
> +
> +STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header)
> +{
> + stbi__zbuf a;
> + char *p = (char *) stbi__malloc(initial_size);
> + if (p == NULL) return NULL;
> + a.zbuffer = (stbi_uc *) buffer;
> + a.zbuffer_end = (stbi_uc *) buffer + len;
> + if (stbi__do_zlib(&a, p, initial_size, 1, parse_header)) {
> + if (outlen) *outlen = (int) (a.zout - a.zout_start);
> + return a.zout_start;
> + } else {
> + STBI_FREE(a.zout_start);
> + return NULL;
> + }
> +}
> +
> +STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen)
> +{
> + stbi__zbuf a;
> + a.zbuffer = (stbi_uc *) ibuffer;
> + a.zbuffer_end = (stbi_uc *) ibuffer + ilen;
> + if (stbi__do_zlib(&a, obuffer, olen, 0, 1))
> + return (int) (a.zout - a.zout_start);
> + else
> + return -1;
> +}
> +
> +STBIDEF char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen)
> +{
> + stbi__zbuf a;
> + char *p = (char *) stbi__malloc(16384);
> + if (p == NULL) return NULL;
> + a.zbuffer = (stbi_uc *) buffer;
> + a.zbuffer_end = (stbi_uc *) buffer+len;
> + if (stbi__do_zlib(&a, p, 16384, 1, 0)) {
> + if (outlen) *outlen = (int) (a.zout - a.zout_start);
> + return a.zout_start;
> + } else {
> + STBI_FREE(a.zout_start);
> + return NULL;
> + }
> +}
> +
> +STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen)
> +{
> + stbi__zbuf a;
> + a.zbuffer = (stbi_uc *) ibuffer;
> + a.zbuffer_end = (stbi_uc *) ibuffer + ilen;
> + if (stbi__do_zlib(&a, obuffer, olen, 0, 0))
> + return (int) (a.zout - a.zout_start);
> + else
> + return -1;
> +}
> +#endif
> +
> +// public domain "baseline" PNG decoder v0.10 Sean Barrett 2006-11-18
> +// simple implementation
> +// - only 8-bit samples
> +// - no CRC checking
> +// - allocates lots of intermediate memory
> +// - avoids problem of streaming data between subsystems
> +// - avoids explicit window management
> +// performance
> +// - uses stb_zlib, a PD zlib implementation with fast huffman decoding
> +
> +#ifndef STBI_NO_PNG
> +typedef struct
> +{
> + stbi__uint32 length;
> + stbi__uint32 type;
> +} stbi__pngchunk;
> +
> +static stbi__pngchunk stbi__get_chunk_header(stbi__context *s)
> +{
> + stbi__pngchunk c;
> + c.length = stbi__get32be(s);
> + c.type = stbi__get32be(s);
> + return c;
> +}
> +
> +static int stbi__check_png_header(stbi__context *s)
> +{
> + static const stbi_uc png_sig[8] = { 137,80,78,71,13,10,26,10 };
> + int i;
> + for (i=0; i < 8; ++i)
> + if (stbi__get8(s) != png_sig[i]) return stbi__err("bad png sig","Not a PNG");
> + return 1;
> +}
> +
> +typedef struct
> +{
> + stbi__context *s;
> + stbi_uc *idata, *expanded, *out;
> + int depth;
> +} stbi__png;
> +
> +
> +enum {
> + STBI__F_none=0,
> + STBI__F_sub=1,
> + STBI__F_up=2,
> + STBI__F_avg=3,
> + STBI__F_paeth=4,
> + // synthetic filters used for first scanline to avoid needing a dummy row of 0s
> + STBI__F_avg_first,
> + STBI__F_paeth_first
> +};
> +
> +static stbi_uc first_row_filter[5] =
> +{
> + STBI__F_none,
> + STBI__F_sub,
> + STBI__F_none,
> + STBI__F_avg_first,
> + STBI__F_paeth_first
> +};
> +
> +static int stbi__paeth(int a, int b, int c)
> +{
> + int p = a + b - c;
> + int pa = abs(p-a);
> + int pb = abs(p-b);
> + int pc = abs(p-c);
> + if (pa <= pb && pa <= pc) return a;
> + if (pb <= pc) return b;
> + return c;
> +}
> +
> +static const stbi_uc stbi__depth_scale_table[9] = { 0, 0xff, 0x55, 0, 0x11, 0,0,0, 0x01 };
> +
> +// create the png data from post-deflated data
> +static int stbi__create_png_image_raw(stbi__png *a, stbi_uc *raw, stbi__uint32 raw_len, int out_n, stbi__uint32 x, stbi__uint32 y, int depth, int color)
> +{
> + int bytes = (depth == 16? 2 : 1);
> + stbi__context *s = a->s;
> + stbi__uint32 i,j,stride = x*out_n*bytes;
> + stbi__uint32 img_len, img_width_bytes;
> + int k;
> + int img_n = s->img_n; // copy it into a local for later
> +
> + int output_bytes = out_n*bytes;
> + int filter_bytes = img_n*bytes;
> + int width = x;
> +
> + STBI_ASSERT(out_n == s->img_n || out_n == s->img_n+1);
> + a->out = (stbi_uc *) stbi__malloc_mad3(x, y, output_bytes, 0); // extra bytes to write off the end into
> + if (!a->out) return stbi__err("outofmem", "Out of memory");
> +
> + if (!stbi__mad3sizes_valid(img_n, x, depth, 7)) return stbi__err("too large", "Corrupt PNG");
> + img_width_bytes = (((img_n * x * depth) + 7) >> 3);
> + img_len = (img_width_bytes + 1) * y;
> +
> + // we used to check for exact match between raw_len and img_len on non-interlaced PNGs,
> + // but issue #276 reported a PNG in the wild that had extra data at the end (all zeros),
> + // so just check for raw_len < img_len always.
> + if (raw_len < img_len) return stbi__err("not enough pixels","Corrupt PNG");
> +
> + for (j=0; j < y; ++j) {
> + stbi_uc *cur = a->out + stride*j;
> + stbi_uc *prior;
> + int filter = *raw++;
> +
> + if (filter > 4)
> + return stbi__err("invalid filter","Corrupt PNG");
> +
> + if (depth < 8) {
> + if (img_width_bytes > x) return stbi__err("invalid width","Corrupt PNG");
> + cur += x*out_n - img_width_bytes; // store output to the rightmost img_len bytes, so we can decode in place
> + filter_bytes = 1;
> + width = img_width_bytes;
> + }
> + prior = cur - stride; // bugfix: need to compute this after 'cur +=' computation above
> +
> + // if first row, use special filter that doesn't sample previous row
> + if (j == 0) filter = first_row_filter[filter];
> +
> + // handle first byte explicitly
> + for (k=0; k < filter_bytes; ++k) {
> + switch (filter) {
> + case STBI__F_none : cur[k] = raw[k]; break;
> + case STBI__F_sub : cur[k] = raw[k]; break;
> + case STBI__F_up : cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
> + case STBI__F_avg : cur[k] = STBI__BYTECAST(raw[k] + (prior[k]>>1)); break;
> + case STBI__F_paeth : cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(0,prior[k],0)); break;
> + case STBI__F_avg_first : cur[k] = raw[k]; break;
> + case STBI__F_paeth_first: cur[k] = raw[k]; break;
> + }
> + }
> +
> + if (depth == 8) {
> + if (img_n != out_n)
> + cur[img_n] = 255; // first pixel
> + raw += img_n;
> + cur += out_n;
> + prior += out_n;
> + } else if (depth == 16) {
> + if (img_n != out_n) {
> + cur[filter_bytes] = 255; // first pixel top byte
> + cur[filter_bytes+1] = 255; // first pixel bottom byte
> + }
> + raw += filter_bytes;
> + cur += output_bytes;
> + prior += output_bytes;
> + } else {
> + raw += 1;
> + cur += 1;
> + prior += 1;
> + }
> +
> + // this is a little gross, so that we don't switch per-pixel or per-component
> + if (depth < 8 || img_n == out_n) {
> + int nk = (width - 1)*filter_bytes;
> + #define STBI__CASE(f) \
> + case f: \
> + for (k=0; k < nk; ++k)
> + switch (filter) {
> + // "none" filter turns into a memcpy here; make that explicit.
> + case STBI__F_none: memcpy(cur, raw, nk); break;
> + STBI__CASE(STBI__F_sub) { cur[k] = STBI__BYTECAST(raw[k] + cur[k-filter_bytes]); } break;
> + STBI__CASE(STBI__F_up) { cur[k] = STBI__BYTECAST(raw[k] + prior[k]); } break;
> + STBI__CASE(STBI__F_avg) { cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k-filter_bytes])>>1)); } break;
> + STBI__CASE(STBI__F_paeth) { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],prior[k],prior[k-filter_bytes])); } break;
> + STBI__CASE(STBI__F_avg_first) { cur[k] = STBI__BYTECAST(raw[k] + (cur[k-filter_bytes] >> 1)); } break;
> + STBI__CASE(STBI__F_paeth_first) { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],0,0)); } break;
> + }
> + #undef STBI__CASE
> + raw += nk;
> + } else {
> + STBI_ASSERT(img_n+1 == out_n);
> + #define STBI__CASE(f) \
> + case f: \
> + for (i=x-1; i >= 1; --i, cur[filter_bytes]=255,raw+=filter_bytes,cur+=output_bytes,prior+=output_bytes) \
> + for (k=0; k < filter_bytes; ++k)
> + switch (filter) {
> + STBI__CASE(STBI__F_none) { cur[k] = raw[k]; } break;
> + STBI__CASE(STBI__F_sub) { cur[k] = STBI__BYTECAST(raw[k] + cur[k- output_bytes]); } break;
> + STBI__CASE(STBI__F_up) { cur[k] = STBI__BYTECAST(raw[k] + prior[k]); } break;
> + STBI__CASE(STBI__F_avg) { cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k- output_bytes])>>1)); } break;
> + STBI__CASE(STBI__F_paeth) { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k- output_bytes],prior[k],prior[k- output_bytes])); } break;
> + STBI__CASE(STBI__F_avg_first) { cur[k] = STBI__BYTECAST(raw[k] + (cur[k- output_bytes] >> 1)); } break;
> + STBI__CASE(STBI__F_paeth_first) { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k- output_bytes],0,0)); } break;
> + }
> + #undef STBI__CASE
> +
> + // the loop above sets the high byte of the pixels' alpha, but for
> + // 16 bit png files we also need the low byte set. we'll do that here.
> + if (depth == 16) {
> + cur = a->out + stride*j; // start at the beginning of the row again
> + for (i=0; i < x; ++i,cur+=output_bytes) {
> + cur[filter_bytes+1] = 255;
> + }
> + }
> + }
> + }
> +
> + // we make a separate pass to expand bits to pixels; for performance,
> + // this could run two scanlines behind the above code, so it won't
> + // intefere with filtering but will still be in the cache.
> + if (depth < 8) {
> + for (j=0; j < y; ++j) {
> + stbi_uc *cur = a->out + stride*j;
> + stbi_uc *in = a->out + stride*j + x*out_n - img_width_bytes;
> + // unpack 1/2/4-bit into a 8-bit buffer. allows us to keep the common 8-bit path optimal at minimal cost for 1/2/4-bit
> + // png guarante byte alignment, if width is not multiple of 8/4/2 we'll decode dummy trailing data that will be skipped in the later loop
> + stbi_uc scale = (color == 0) ? stbi__depth_scale_table[depth] : 1; // scale grayscale values to 0..255 range
> +
> + // note that the final byte might overshoot and write more data than desired.
> + // we can allocate enough data that this never writes out of memory, but it
> + // could also overwrite the next scanline. can it overwrite non-empty data
> + // on the next scanline? yes, consider 1-pixel-wide scanlines with 1-bit-per-pixel.
> + // so we need to explicitly clamp the final ones
> +
> + if (depth == 4) {
> + for (k=x*img_n; k >= 2; k-=2, ++in) {
> + *cur++ = scale * ((*in >> 4) );
> + *cur++ = scale * ((*in ) & 0x0f);
> + }
> + if (k > 0) *cur++ = scale * ((*in >> 4) );
> + } else if (depth == 2) {
> + for (k=x*img_n; k >= 4; k-=4, ++in) {
> + *cur++ = scale * ((*in >> 6) );
> + *cur++ = scale * ((*in >> 4) & 0x03);
> + *cur++ = scale * ((*in >> 2) & 0x03);
> + *cur++ = scale * ((*in ) & 0x03);
> + }
> + if (k > 0) *cur++ = scale * ((*in >> 6) );
> + if (k > 1) *cur++ = scale * ((*in >> 4) & 0x03);
> + if (k > 2) *cur++ = scale * ((*in >> 2) & 0x03);
> + } else if (depth == 1) {
> + for (k=x*img_n; k >= 8; k-=8, ++in) {
> + *cur++ = scale * ((*in >> 7) );
> + *cur++ = scale * ((*in >> 6) & 0x01);
> + *cur++ = scale * ((*in >> 5) & 0x01);
> + *cur++ = scale * ((*in >> 4) & 0x01);
> + *cur++ = scale * ((*in >> 3) & 0x01);
> + *cur++ = scale * ((*in >> 2) & 0x01);
> + *cur++ = scale * ((*in >> 1) & 0x01);
> + *cur++ = scale * ((*in ) & 0x01);
> + }
> + if (k > 0) *cur++ = scale * ((*in >> 7) );
> + if (k > 1) *cur++ = scale * ((*in >> 6) & 0x01);
> + if (k > 2) *cur++ = scale * ((*in >> 5) & 0x01);
> + if (k > 3) *cur++ = scale * ((*in >> 4) & 0x01);
> + if (k > 4) *cur++ = scale * ((*in >> 3) & 0x01);
> + if (k > 5) *cur++ = scale * ((*in >> 2) & 0x01);
> + if (k > 6) *cur++ = scale * ((*in >> 1) & 0x01);
> + }
> + if (img_n != out_n) {
> + int q;
> + // insert alpha = 255
> + cur = a->out + stride*j;
> + if (img_n == 1) {
> + for (q=x-1; q >= 0; --q) {
> + cur[q*2+1] = 255;
> + cur[q*2+0] = cur[q];
> + }
> + } else {
> + STBI_ASSERT(img_n == 3);
> + for (q=x-1; q >= 0; --q) {
> + cur[q*4+3] = 255;
> + cur[q*4+2] = cur[q*3+2];
> + cur[q*4+1] = cur[q*3+1];
> + cur[q*4+0] = cur[q*3+0];
> + }
> + }
> + }
> + }
> + } else if (depth == 16) {
> + // force the image data from big-endian to platform-native.
> + // this is done in a separate pass due to the decoding relying
> + // on the data being untouched, but could probably be done
> + // per-line during decode if care is taken.
> + stbi_uc *cur = a->out;
> + stbi__uint16 *cur16 = (stbi__uint16*)cur;
> +
> + for(i=0; i < x*y*out_n; ++i,cur16++,cur+=2) {
> + *cur16 = (cur[0] << 8) | cur[1];
> + }
> + }
> +
> + return 1;
> +}
> +
> +static int stbi__create_png_image(stbi__png *a, stbi_uc *image_data, stbi__uint32 image_data_len, int out_n, int depth, int color, int interlaced)
> +{
> + int bytes = (depth == 16 ? 2 : 1);
> + int out_bytes = out_n * bytes;
> + stbi_uc *final;
> + int p;
> + if (!interlaced)
> + return stbi__create_png_image_raw(a, image_data, image_data_len, out_n, a->s->img_x, a->s->img_y, depth, color);
> +
> + // de-interlacing
> + final = (stbi_uc *) stbi__malloc_mad3(a->s->img_x, a->s->img_y, out_bytes, 0);
> + for (p=0; p < 7; ++p) {
> + int xorig[] = { 0,4,0,2,0,1,0 };
> + int yorig[] = { 0,0,4,0,2,0,1 };
> + int xspc[] = { 8,8,4,4,2,2,1 };
> + int yspc[] = { 8,8,8,4,4,2,2 };
> + int i,j,x,y;
> + // pass1_x[4] = 0, pass1_x[5] = 1, pass1_x[12] = 1
> + x = (a->s->img_x - xorig[p] + xspc[p]-1) / xspc[p];
> + y = (a->s->img_y - yorig[p] + yspc[p]-1) / yspc[p];
> + if (x && y) {
> + stbi__uint32 img_len = ((((a->s->img_n * x * depth) + 7) >> 3) + 1) * y;
> + if (!stbi__create_png_image_raw(a, image_data, image_data_len, out_n, x, y, depth, color)) {
> + STBI_FREE(final);
> + return 0;
> + }
> + for (j=0; j < y; ++j) {
> + for (i=0; i < x; ++i) {
> + int out_y = j*yspc[p]+yorig[p];
> + int out_x = i*xspc[p]+xorig[p];
> + memcpy(final + out_y*a->s->img_x*out_bytes + out_x*out_bytes,
> + a->out + (j*x+i)*out_bytes, out_bytes);
> + }
> + }
> + STBI_FREE(a->out);
> + image_data += img_len;
> + image_data_len -= img_len;
> + }
> + }
> + a->out = final;
> +
> + return 1;
> +}
> +
> +static int stbi__compute_transparency(stbi__png *z, stbi_uc tc[3], int out_n)
> +{
> + stbi__context *s = z->s;
> + stbi__uint32 i, pixel_count = s->img_x * s->img_y;
> + stbi_uc *p = z->out;
> +
> + // compute color-based transparency, assuming we've
> + // already got 255 as the alpha value in the output
> + STBI_ASSERT(out_n == 2 || out_n == 4);
> +
> + if (out_n == 2) {
> + for (i=0; i < pixel_count; ++i) {
> + p[1] = (p[0] == tc[0] ? 0 : 255);
> + p += 2;
> + }
> + } else {
> + for (i=0; i < pixel_count; ++i) {
> + if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2])
> + p[3] = 0;
> + p += 4;
> + }
> + }
> + return 1;
> +}
> +
> +static int stbi__compute_transparency16(stbi__png *z, stbi__uint16 tc[3], int out_n)
> +{
> + stbi__context *s = z->s;
> + stbi__uint32 i, pixel_count = s->img_x * s->img_y;
> + stbi__uint16 *p = (stbi__uint16*) z->out;
> +
> + // compute color-based transparency, assuming we've
> + // already got 65535 as the alpha value in the output
> + STBI_ASSERT(out_n == 2 || out_n == 4);
> +
> + if (out_n == 2) {
> + for (i = 0; i < pixel_count; ++i) {
> + p[1] = (p[0] == tc[0] ? 0 : 65535);
> + p += 2;
> + }
> + } else {
> + for (i = 0; i < pixel_count; ++i) {
> + if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2])
> + p[3] = 0;
> + p += 4;
> + }
> + }
> + return 1;
> +}
> +
> +static int stbi__expand_png_palette(stbi__png *a, stbi_uc *palette, int len, int pal_img_n)
> +{
> + stbi__uint32 i, pixel_count = a->s->img_x * a->s->img_y;
> + stbi_uc *p, *temp_out, *orig = a->out;
> +
> + p = (stbi_uc *) stbi__malloc_mad2(pixel_count, pal_img_n, 0);
> + if (p == NULL) return stbi__err("outofmem", "Out of memory");
> +
> + // between here and free(out) below, exitting would leak
> + temp_out = p;
> +
> + if (pal_img_n == 3) {
> + for (i=0; i < pixel_count; ++i) {
> + int n = orig[i]*4;
> + p[0] = palette[n ];
> + p[1] = palette[n+1];
> + p[2] = palette[n+2];
> + p += 3;
> + }
> + } else {
> + for (i=0; i < pixel_count; ++i) {
> + int n = orig[i]*4;
> + p[0] = palette[n ];
> + p[1] = palette[n+1];
> + p[2] = palette[n+2];
> + p[3] = palette[n+3];
> + p += 4;
> + }
> + }
> + STBI_FREE(a->out);
> + a->out = temp_out;
> +
> + STBI_NOTUSED(len);
> +
> + return 1;
> +}
> +
> +static int stbi__unpremultiply_on_load = 0;
> +static int stbi__de_iphone_flag = 0;
> +
> +STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply)
> +{
> + stbi__unpremultiply_on_load = flag_true_if_should_unpremultiply;
> +}
> +
> +STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert)
> +{
> + stbi__de_iphone_flag = flag_true_if_should_convert;
> +}
> +
> +static void stbi__de_iphone(stbi__png *z)
> +{
> + stbi__context *s = z->s;
> + stbi__uint32 i, pixel_count = s->img_x * s->img_y;
> + stbi_uc *p = z->out;
> +
> + if (s->img_out_n == 3) { // convert bgr to rgb
> + for (i=0; i < pixel_count; ++i) {
> + stbi_uc t = p[0];
> + p[0] = p[2];
> + p[2] = t;
> + p += 3;
> + }
> + } else {
> + STBI_ASSERT(s->img_out_n == 4);
> + if (stbi__unpremultiply_on_load) {
> + // convert bgr to rgb and unpremultiply
> + for (i=0; i < pixel_count; ++i) {
> + stbi_uc a = p[3];
> + stbi_uc t = p[0];
> + if (a) {
> + stbi_uc half = a / 2;
> + p[0] = (p[2] * 255 + half) / a;
> + p[1] = (p[1] * 255 + half) / a;
> + p[2] = ( t * 255 + half) / a;
> + } else {
> + p[0] = p[2];
> + p[2] = t;
> + }
> + p += 4;
> + }
> + } else {
> + // convert bgr to rgb
> + for (i=0; i < pixel_count; ++i) {
> + stbi_uc t = p[0];
> + p[0] = p[2];
> + p[2] = t;
> + p += 4;
> + }
> + }
> + }
> +}
> +
> +#define STBI__PNG_TYPE(a,b,c,d) (((unsigned) (a) << 24) + ((unsigned) (b) << 16) + ((unsigned) (c) << 8) + (unsigned) (d))
> +
> +static int stbi__parse_png_file(stbi__png *z, int scan, int req_comp)
> +{
> + stbi_uc palette[1024], pal_img_n=0;
> + stbi_uc has_trans=0, tc[3]={0};
> + stbi__uint16 tc16[3];
> + stbi__uint32 ioff=0, idata_limit=0, i, pal_len=0;
> + int first=1,k,interlace=0, color=0, is_iphone=0;
> + stbi__context *s = z->s;
> +
> + z->expanded = NULL;
> + z->idata = NULL;
> + z->out = NULL;
> +
> + if (!stbi__check_png_header(s)) return 0;
> +
> + if (scan == STBI__SCAN_type) return 1;
> +
> + for (;;) {
> + stbi__pngchunk c = stbi__get_chunk_header(s);
> + switch (c.type) {
> + case STBI__PNG_TYPE('C','g','B','I'):
> + is_iphone = 1;
> + stbi__skip(s, c.length);
> + break;
> + case STBI__PNG_TYPE('I','H','D','R'): {
> + int comp,filter;
> + if (!first) return stbi__err("multiple IHDR","Corrupt PNG");
> + first = 0;
> + if (c.length != 13) return stbi__err("bad IHDR len","Corrupt PNG");
> + s->img_x = stbi__get32be(s);
> + s->img_y = stbi__get32be(s);
> + if (s->img_y > STBI_MAX_DIMENSIONS) return stbi__err("too large","Very large image (corrupt?)");
> + if (s->img_x > STBI_MAX_DIMENSIONS) return stbi__err("too large","Very large image (corrupt?)");
> + z->depth = stbi__get8(s); if (z->depth != 1 && z->depth != 2 && z->depth != 4 && z->depth != 8 && z->depth != 16) return stbi__err("1/2/4/8/16-bit only","PNG not supported: 1/2/4/8/16-bit only");
> + color = stbi__get8(s); if (color > 6) return stbi__err("bad ctype","Corrupt PNG");
> + if (color == 3 && z->depth == 16) return stbi__err("bad ctype","Corrupt PNG");
> + if (color == 3) pal_img_n = 3; else if (color & 1) return stbi__err("bad ctype","Corrupt PNG");
> + comp = stbi__get8(s); if (comp) return stbi__err("bad comp method","Corrupt PNG");
> + filter= stbi__get8(s); if (filter) return stbi__err("bad filter method","Corrupt PNG");
> + interlace = stbi__get8(s); if (interlace>1) return stbi__err("bad interlace method","Corrupt PNG");
> + if (!s->img_x || !s->img_y) return stbi__err("0-pixel image","Corrupt PNG");
> + if (!pal_img_n) {
> + s->img_n = (color & 2 ? 3 : 1) + (color & 4 ? 1 : 0);
> + if ((1 << 30) / s->img_x / s->img_n < s->img_y) return stbi__err("too large", "Image too large to decode");
> + if (scan == STBI__SCAN_header) return 1;
> + } else {
> + // if paletted, then pal_n is our final components, and
> + // img_n is # components to decompress/filter.
> + s->img_n = 1;
> + if ((1 << 30) / s->img_x / 4 < s->img_y) return stbi__err("too large","Corrupt PNG");
> + // if SCAN_header, have to scan to see if we have a tRNS
> + }
> + break;
> + }
> +
> + case STBI__PNG_TYPE('P','L','T','E'): {
> + if (first) return stbi__err("first not IHDR", "Corrupt PNG");
> + if (c.length > 256*3) return stbi__err("invalid PLTE","Corrupt PNG");
> + pal_len = c.length / 3;
> + if (pal_len * 3 != c.length) return stbi__err("invalid PLTE","Corrupt PNG");
> + for (i=0; i < pal_len; ++i) {
> + palette[i*4+0] = stbi__get8(s);
> + palette[i*4+1] = stbi__get8(s);
> + palette[i*4+2] = stbi__get8(s);
> + palette[i*4+3] = 255;
> + }
> + break;
> + }
> +
> + case STBI__PNG_TYPE('t','R','N','S'): {
> + if (first) return stbi__err("first not IHDR", "Corrupt PNG");
> + if (z->idata) return stbi__err("tRNS after IDAT","Corrupt PNG");
> + if (pal_img_n) {
> + if (scan == STBI__SCAN_header) { s->img_n = 4; return 1; }
> + if (pal_len == 0) return stbi__err("tRNS before PLTE","Corrupt PNG");
> + if (c.length > pal_len) return stbi__err("bad tRNS len","Corrupt PNG");
> + pal_img_n = 4;
> + for (i=0; i < c.length; ++i)
> + palette[i*4+3] = stbi__get8(s);
> + } else {
> + if (!(s->img_n & 1)) return stbi__err("tRNS with alpha","Corrupt PNG");
> + if (c.length != (stbi__uint32) s->img_n*2) return stbi__err("bad tRNS len","Corrupt PNG");
> + has_trans = 1;
> + if (z->depth == 16) {
> + for (k = 0; k < s->img_n; ++k) tc16[k] = (stbi__uint16)stbi__get16be(s); // copy the values as-is
> + } else {
> + for (k = 0; k < s->img_n; ++k) tc[k] = (stbi_uc)(stbi__get16be(s) & 255) * stbi__depth_scale_table[z->depth]; // non 8-bit images will be larger
> + }
> + }
> + break;
> + }
> +
> + case STBI__PNG_TYPE('I','D','A','T'): {
> + if (first) return stbi__err("first not IHDR", "Corrupt PNG");
> + if (pal_img_n && !pal_len) return stbi__err("no PLTE","Corrupt PNG");
> + if (scan == STBI__SCAN_header) { s->img_n = pal_img_n; return 1; }
> + if ((int)(ioff + c.length) < (int)ioff) return 0;
> + if (ioff + c.length > idata_limit) {
> + stbi__uint32 idata_limit_old = idata_limit;
> + stbi_uc *p;
> + if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096;
> + while (ioff + c.length > idata_limit)
> + idata_limit *= 2;
> + STBI_NOTUSED(idata_limit_old);
> + p = (stbi_uc *) STBI_REALLOC_SIZED(z->idata, idata_limit_old, idata_limit); if (p == NULL) return stbi__err("outofmem", "Out of memory");
> + z->idata = p;
> + }
> + if (!stbi__getn(s, z->idata+ioff,c.length)) return stbi__err("outofdata","Corrupt PNG");
> + ioff += c.length;
> + break;
> + }
> +
> + case STBI__PNG_TYPE('I','E','N','D'): {
> + stbi__uint32 raw_len, bpl;
> + if (first) return stbi__err("first not IHDR", "Corrupt PNG");
> + if (scan != STBI__SCAN_load) return 1;
> + if (z->idata == NULL) return stbi__err("no IDAT","Corrupt PNG");
> + // initial guess for decoded data size to avoid unnecessary reallocs
> + bpl = (s->img_x * z->depth + 7) / 8; // bytes per line, per component
> + raw_len = bpl * s->img_y * s->img_n /* pixels */ + s->img_y /* filter mode per row */;
> + z->expanded = (stbi_uc *) stbi_zlib_decode_malloc_guesssize_headerflag((char *) z->idata, ioff, raw_len, (int *) &raw_len, !is_iphone);
> + if (z->expanded == NULL) return 0; // zlib should set error
> + STBI_FREE(z->idata); z->idata = NULL;
> + if ((req_comp == s->img_n+1 && req_comp != 3 && !pal_img_n) || has_trans)
> + s->img_out_n = s->img_n+1;
> + else
> + s->img_out_n = s->img_n;
> + if (!stbi__create_png_image(z, z->expanded, raw_len, s->img_out_n, z->depth, color, interlace)) return 0;
> + if (has_trans) {
> + if (z->depth == 16) {
> + if (!stbi__compute_transparency16(z, tc16, s->img_out_n)) return 0;
> + } else {
> + if (!stbi__compute_transparency(z, tc, s->img_out_n)) return 0;
> + }
> + }
> + if (is_iphone && stbi__de_iphone_flag && s->img_out_n > 2)
> + stbi__de_iphone(z);
> + if (pal_img_n) {
> + // pal_img_n == 3 or 4
> + s->img_n = pal_img_n; // record the actual colors we had
> + s->img_out_n = pal_img_n;
> + if (req_comp >= 3) s->img_out_n = req_comp;
> + if (!stbi__expand_png_palette(z, palette, pal_len, s->img_out_n))
> + return 0;
> + } else if (has_trans) {
> + // non-paletted image with tRNS -> source image has (constant) alpha
> + ++s->img_n;
> + }
> + STBI_FREE(z->expanded); z->expanded = NULL;
> + // end of PNG chunk, read and skip CRC
> + stbi__get32be(s);
> + return 1;
> + }
> +
> + default:
> + // if critical, fail
> + if (first) return stbi__err("first not IHDR", "Corrupt PNG");
> + if ((c.type & (1 << 29)) == 0) {
> + #ifndef STBI_NO_FAILURE_STRINGS
> + // not threadsafe
> + static char invalid_chunk[] = "XXXX PNG chunk not known";
> + invalid_chunk[0] = STBI__BYTECAST(c.type >> 24);
> + invalid_chunk[1] = STBI__BYTECAST(c.type >> 16);
> + invalid_chunk[2] = STBI__BYTECAST(c.type >> 8);
> + invalid_chunk[3] = STBI__BYTECAST(c.type >> 0);
> + #endif
> + return stbi__err(invalid_chunk, "PNG not supported: unknown PNG chunk type");
> + }
> + stbi__skip(s, c.length);
> + break;
> + }
> + // end of PNG chunk, read and skip CRC
> + stbi__get32be(s);
> + }
> +}
> +
> +static void *stbi__do_png(stbi__png *p, int *x, int *y, int *n, int req_comp, stbi__result_info *ri)
> +{
> + void *result=NULL;
> + if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error");
> + if (stbi__parse_png_file(p, STBI__SCAN_load, req_comp)) {
> + if (p->depth <= 8)
> + ri->bits_per_channel = 8;
> + else if (p->depth == 16)
> + ri->bits_per_channel = 16;
> + else
> + return stbi__errpuc("bad bits_per_channel", "PNG not supported: unsupported color depth");
> + result = p->out;
> + p->out = NULL;
> + if (req_comp && req_comp != p->s->img_out_n) {
> + if (ri->bits_per_channel == 8)
> + result = stbi__convert_format((unsigned char *) result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y);
> + else
> + result = stbi__convert_format16((stbi__uint16 *) result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y);
> + p->s->img_out_n = req_comp;
> + if (result == NULL) return result;
> + }
> + *x = p->s->img_x;
> + *y = p->s->img_y;
> + if (n) *n = p->s->img_n;
> + }
> + STBI_FREE(p->out); p->out = NULL;
> + STBI_FREE(p->expanded); p->expanded = NULL;
> + STBI_FREE(p->idata); p->idata = NULL;
> +
> + return result;
> +}
> +
> +static void *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
> +{
> + stbi__png p;
> + p.s = s;
> + return stbi__do_png(&p, x,y,comp,req_comp, ri);
> +}
> +
> +static int stbi__png_test(stbi__context *s)
> +{
> + int r;
> + r = stbi__check_png_header(s);
> + stbi__rewind(s);
> + return r;
> +}
> +
> +static int stbi__png_info_raw(stbi__png *p, int *x, int *y, int *comp)
> +{
> + if (!stbi__parse_png_file(p, STBI__SCAN_header, 0)) {
> + stbi__rewind( p->s );
> + return 0;
> + }
> + if (x) *x = p->s->img_x;
> + if (y) *y = p->s->img_y;
> + if (comp) *comp = p->s->img_n;
> + return 1;
> +}
> +
> +static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + stbi__png p;
> + p.s = s;
> + return stbi__png_info_raw(&p, x, y, comp);
> +}
> +
> +static int stbi__png_is16(stbi__context *s)
> +{
> + stbi__png p;
> + p.s = s;
> + if (!stbi__png_info_raw(&p, NULL, NULL, NULL))
> + return 0;
> + if (p.depth != 16) {
> + stbi__rewind(p.s);
> + return 0;
> + }
> + return 1;
> +}
> +#endif
> +
> +// Microsoft/Windows BMP image
> +
> +#ifndef STBI_NO_BMP
> +static int stbi__bmp_test_raw(stbi__context *s)
> +{
> + int r;
> + int sz;
> + if (stbi__get8(s) != 'B') return 0;
> + if (stbi__get8(s) != 'M') return 0;
> + stbi__get32le(s); // discard filesize
> + stbi__get16le(s); // discard reserved
> + stbi__get16le(s); // discard reserved
> + stbi__get32le(s); // discard data offset
> + sz = stbi__get32le(s);
> + r = (sz == 12 || sz == 40 || sz == 56 || sz == 108 || sz == 124);
> + return r;
> +}
> +
> +static int stbi__bmp_test(stbi__context *s)
> +{
> + int r = stbi__bmp_test_raw(s);
> + stbi__rewind(s);
> + return r;
> +}
> +
> +
> +// returns 0..31 for the highest set bit
> +static int stbi__high_bit(unsigned int z)
> +{
> + int n=0;
> + if (z == 0) return -1;
> + if (z >= 0x10000) { n += 16; z >>= 16; }
> + if (z >= 0x00100) { n += 8; z >>= 8; }
> + if (z >= 0x00010) { n += 4; z >>= 4; }
> + if (z >= 0x00004) { n += 2; z >>= 2; }
> + if (z >= 0x00002) { n += 1;/* >>= 1;*/ }
> + return n;
> +}
> +
> +static int stbi__bitcount(unsigned int a)
> +{
> + a = (a & 0x55555555) + ((a >> 1) & 0x55555555); // max 2
> + a = (a & 0x33333333) + ((a >> 2) & 0x33333333); // max 4
> + a = (a + (a >> 4)) & 0x0f0f0f0f; // max 8 per 4, now 8 bits
> + a = (a + (a >> 8)); // max 16 per 8 bits
> + a = (a + (a >> 16)); // max 32 per 8 bits
> + return a & 0xff;
> +}
> +
> +// extract an arbitrarily-aligned N-bit value (N=bits)
> +// from v, and then make it 8-bits long and fractionally
> +// extend it to full full range.
> +static int stbi__shiftsigned(unsigned int v, int shift, int bits)
> +{
> + static unsigned int mul_table[9] = {
> + 0,
> + 0xff/*0b11111111*/, 0x55/*0b01010101*/, 0x49/*0b01001001*/, 0x11/*0b00010001*/,
> + 0x21/*0b00100001*/, 0x41/*0b01000001*/, 0x81/*0b10000001*/, 0x01/*0b00000001*/,
> + };
> + static unsigned int shift_table[9] = {
> + 0, 0,0,1,0,2,4,6,0,
> + };
> + if (shift < 0)
> + v <<= -shift;
> + else
> + v >>= shift;
> + STBI_ASSERT(v < 256);
> + v >>= (8-bits);
> + STBI_ASSERT(bits >= 0 && bits <= 8);
> + return (int) ((unsigned) v * mul_table[bits]) >> shift_table[bits];
> +}
> +
> +typedef struct
> +{
> + int bpp, offset, hsz;
> + unsigned int mr,mg,mb,ma, all_a;
> + int extra_read;
> +} stbi__bmp_data;
> +
> +static void *stbi__bmp_parse_header(stbi__context *s, stbi__bmp_data *info)
> +{
> + int hsz;
> + if (stbi__get8(s) != 'B' || stbi__get8(s) != 'M') return stbi__errpuc("not BMP", "Corrupt BMP");
> + stbi__get32le(s); // discard filesize
> + stbi__get16le(s); // discard reserved
> + stbi__get16le(s); // discard reserved
> + info->offset = stbi__get32le(s);
> + info->hsz = hsz = stbi__get32le(s);
> + info->mr = info->mg = info->mb = info->ma = 0;
> + info->extra_read = 14;
> +
> + if (info->offset < 0) return stbi__errpuc("bad BMP", "bad BMP");
> +
> + if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108 && hsz != 124) return stbi__errpuc("unknown BMP", "BMP type not supported: unknown");
> + if (hsz == 12) {
> + s->img_x = stbi__get16le(s);
> + s->img_y = stbi__get16le(s);
> + } else {
> + s->img_x = stbi__get32le(s);
> + s->img_y = stbi__get32le(s);
> + }
> + if (stbi__get16le(s) != 1) return stbi__errpuc("bad BMP", "bad BMP");
> + info->bpp = stbi__get16le(s);
> + if (hsz != 12) {
> + int compress = stbi__get32le(s);
> + if (compress == 1 || compress == 2) return stbi__errpuc("BMP RLE", "BMP type not supported: RLE");
> + stbi__get32le(s); // discard sizeof
> + stbi__get32le(s); // discard hres
> + stbi__get32le(s); // discard vres
> + stbi__get32le(s); // discard colorsused
> + stbi__get32le(s); // discard max important
> + if (hsz == 40 || hsz == 56) {
> + if (hsz == 56) {
> + stbi__get32le(s);
> + stbi__get32le(s);
> + stbi__get32le(s);
> + stbi__get32le(s);
> + }
> + if (info->bpp == 16 || info->bpp == 32) {
> + if (compress == 0) {
> + if (info->bpp == 32) {
> + info->mr = 0xffu << 16;
> + info->mg = 0xffu << 8;
> + info->mb = 0xffu << 0;
> + info->ma = 0xffu << 24;
> + info->all_a = 0; // if all_a is 0 at end, then we loaded alpha channel but it was all 0
> + } else {
> + info->mr = 31u << 10;
> + info->mg = 31u << 5;
> + info->mb = 31u << 0;
> + }
> + } else if (compress == 3) {
> + info->mr = stbi__get32le(s);
> + info->mg = stbi__get32le(s);
> + info->mb = stbi__get32le(s);
> + info->extra_read += 12;
> + // not documented, but generated by photoshop and handled by mspaint
> + if (info->mr == info->mg && info->mg == info->mb) {
> + // ?!?!?
> + return stbi__errpuc("bad BMP", "bad BMP");
> + }
> + } else
> + return stbi__errpuc("bad BMP", "bad BMP");
> + }
> + } else {
> + int i;
> + if (hsz != 108 && hsz != 124)
> + return stbi__errpuc("bad BMP", "bad BMP");
> + info->mr = stbi__get32le(s);
> + info->mg = stbi__get32le(s);
> + info->mb = stbi__get32le(s);
> + info->ma = stbi__get32le(s);
> + stbi__get32le(s); // discard color space
> + for (i=0; i < 12; ++i)
> + stbi__get32le(s); // discard color space parameters
> + if (hsz == 124) {
> + stbi__get32le(s); // discard rendering intent
> + stbi__get32le(s); // discard offset of profile data
> + stbi__get32le(s); // discard size of profile data
> + stbi__get32le(s); // discard reserved
> + }
> + }
> + }
> + return (void *) 1;
> +}
> +
> +
> +static void *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
> +{
> + stbi_uc *out;
> + unsigned int mr=0,mg=0,mb=0,ma=0, all_a;
> + stbi_uc pal[256][4];
> + int psize=0,i,j,width;
> + int flip_vertically, pad, target;
> + stbi__bmp_data info;
> + STBI_NOTUSED(ri);
> +
> + info.all_a = 255;
> + if (stbi__bmp_parse_header(s, &info) == NULL)
> + return NULL; // error code already set
> +
> + flip_vertically = ((int) s->img_y) > 0;
> + s->img_y = abs((int) s->img_y);
> +
> + if (s->img_y > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> + if (s->img_x > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> +
> + mr = info.mr;
> + mg = info.mg;
> + mb = info.mb;
> + ma = info.ma;
> + all_a = info.all_a;
> +
> + if (info.hsz == 12) {
> + if (info.bpp < 24)
> + psize = (info.offset - info.extra_read - 24) / 3;
> + } else {
> + if (info.bpp < 16)
> + psize = (info.offset - info.extra_read - info.hsz) >> 2;
> + }
> + if (psize == 0) {
> + STBI_ASSERT(info.offset == s->callback_already_read + (int) (s->img_buffer - s->img_buffer_original));
> + if (info.offset != s->callback_already_read + (s->img_buffer - s->buffer_start)) {
> + return stbi__errpuc("bad offset", "Corrupt BMP");
> + }
> + }
> +
> + if (info.bpp == 24 && ma == 0xff000000)
> + s->img_n = 3;
> + else
> + s->img_n = ma ? 4 : 3;
> + if (req_comp && req_comp >= 3) // we can directly decode 3 or 4
> + target = req_comp;
> + else
> + target = s->img_n; // if they want monochrome, we'll post-convert
> +
> + // sanity-check size
> + if (!stbi__mad3sizes_valid(target, s->img_x, s->img_y, 0))
> + return stbi__errpuc("too large", "Corrupt BMP");
> +
> + out = (stbi_uc *) stbi__malloc_mad3(target, s->img_x, s->img_y, 0);
> + if (!out) return stbi__errpuc("outofmem", "Out of memory");
> + if (info.bpp < 16) {
> + int z=0;
> + if (psize == 0 || psize > 256) { STBI_FREE(out); return stbi__errpuc("invalid", "Corrupt BMP"); }
> + for (i=0; i < psize; ++i) {
> + pal[i][2] = stbi__get8(s);
> + pal[i][1] = stbi__get8(s);
> + pal[i][0] = stbi__get8(s);
> + if (info.hsz != 12) stbi__get8(s);
> + pal[i][3] = 255;
> + }
> + stbi__skip(s, info.offset - info.extra_read - info.hsz - psize * (info.hsz == 12 ? 3 : 4));
> + if (info.bpp == 1) width = (s->img_x + 7) >> 3;
> + else if (info.bpp == 4) width = (s->img_x + 1) >> 1;
> + else if (info.bpp == 8) width = s->img_x;
> + else { STBI_FREE(out); return stbi__errpuc("bad bpp", "Corrupt BMP"); }
> + pad = (-width)&3;
> + if (info.bpp == 1) {
> + for (j=0; j < (int) s->img_y; ++j) {
> + int bit_offset = 7, v = stbi__get8(s);
> + for (i=0; i < (int) s->img_x; ++i) {
> + int color = (v>>bit_offset)&0x1;
> + out[z++] = pal[color][0];
> + out[z++] = pal[color][1];
> + out[z++] = pal[color][2];
> + if (target == 4) out[z++] = 255;
> + if (i+1 == (int) s->img_x) break;
> + if((--bit_offset) < 0) {
> + bit_offset = 7;
> + v = stbi__get8(s);
> + }
> + }
> + stbi__skip(s, pad);
> + }
> + } else {
> + for (j=0; j < (int) s->img_y; ++j) {
> + for (i=0; i < (int) s->img_x; i += 2) {
> + int v=stbi__get8(s),v2=0;
> + if (info.bpp == 4) {
> + v2 = v & 15;
> + v >>= 4;
> + }
> + out[z++] = pal[v][0];
> + out[z++] = pal[v][1];
> + out[z++] = pal[v][2];
> + if (target == 4) out[z++] = 255;
> + if (i+1 == (int) s->img_x) break;
> + v = (info.bpp == 8) ? stbi__get8(s) : v2;
> + out[z++] = pal[v][0];
> + out[z++] = pal[v][1];
> + out[z++] = pal[v][2];
> + if (target == 4) out[z++] = 255;
> + }
> + stbi__skip(s, pad);
> + }
> + }
> + } else {
> + int rshift=0,gshift=0,bshift=0,ashift=0,rcount=0,gcount=0,bcount=0,acount=0;
> + int z = 0;
> + int easy=0;
> + stbi__skip(s, info.offset - info.extra_read - info.hsz);
> + if (info.bpp == 24) width = 3 * s->img_x;
> + else if (info.bpp == 16) width = 2*s->img_x;
> + else /* bpp = 32 and pad = 0 */ width=0;
> + pad = (-width) & 3;
> + if (info.bpp == 24) {
> + easy = 1;
> + } else if (info.bpp == 32) {
> + if (mb == 0xff && mg == 0xff00 && mr == 0x00ff0000 && ma == 0xff000000)
> + easy = 2;
> + }
> + if (!easy) {
> + if (!mr || !mg || !mb) { STBI_FREE(out); return stbi__errpuc("bad masks", "Corrupt BMP"); }
> + // right shift amt to put high bit in position #7
> + rshift = stbi__high_bit(mr)-7; rcount = stbi__bitcount(mr);
> + gshift = stbi__high_bit(mg)-7; gcount = stbi__bitcount(mg);
> + bshift = stbi__high_bit(mb)-7; bcount = stbi__bitcount(mb);
> + ashift = stbi__high_bit(ma)-7; acount = stbi__bitcount(ma);
> + if (rcount > 8 || gcount > 8 || bcount > 8 || acount > 8) { STBI_FREE(out); return stbi__errpuc("bad masks", "Corrupt BMP"); }
> + }
> + for (j=0; j < (int) s->img_y; ++j) {
> + if (easy) {
> + for (i=0; i < (int) s->img_x; ++i) {
> + unsigned char a;
> + out[z+2] = stbi__get8(s);
> + out[z+1] = stbi__get8(s);
> + out[z+0] = stbi__get8(s);
> + z += 3;
> + a = (easy == 2 ? stbi__get8(s) : 255);
> + all_a |= a;
> + if (target == 4) out[z++] = a;
> + }
> + } else {
> + int bpp = info.bpp;
> + for (i=0; i < (int) s->img_x; ++i) {
> + stbi__uint32 v = (bpp == 16 ? (stbi__uint32) stbi__get16le(s) : stbi__get32le(s));
> + unsigned int a;
> + out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mr, rshift, rcount));
> + out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mg, gshift, gcount));
> + out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mb, bshift, bcount));
> + a = (ma ? stbi__shiftsigned(v & ma, ashift, acount) : 255);
> + all_a |= a;
> + if (target == 4) out[z++] = STBI__BYTECAST(a);
> + }
> + }
> + stbi__skip(s, pad);
> + }
> + }
> +
> + // if alpha channel is all 0s, replace with all 255s
> + if (target == 4 && all_a == 0)
> + for (i=4*s->img_x*s->img_y-1; i >= 0; i -= 4)
> + out[i] = 255;
> +
> + if (flip_vertically) {
> + stbi_uc t;
> + for (j=0; j < (int) s->img_y>>1; ++j) {
> + stbi_uc *p1 = out + j *s->img_x*target;
> + stbi_uc *p2 = out + (s->img_y-1-j)*s->img_x*target;
> + for (i=0; i < (int) s->img_x*target; ++i) {
> + t = p1[i]; p1[i] = p2[i]; p2[i] = t;
> + }
> + }
> + }
> +
> + if (req_comp && req_comp != target) {
> + out = stbi__convert_format(out, target, req_comp, s->img_x, s->img_y);
> + if (out == NULL) return out; // stbi__convert_format frees input on failure
> + }
> +
> + *x = s->img_x;
> + *y = s->img_y;
> + if (comp) *comp = s->img_n;
> + return out;
> +}
> +#endif
> +
> +// Targa Truevision - TGA
> +// by Jonathan Dummer
> +#ifndef STBI_NO_TGA
> +// returns STBI_rgb or whatever, 0 on error
> +static int stbi__tga_get_comp(int bits_per_pixel, int is_grey, int* is_rgb16)
> +{
> + // only RGB or RGBA (incl. 16bit) or grey allowed
> + if (is_rgb16) *is_rgb16 = 0;
> + switch(bits_per_pixel) {
> + case 8: return STBI_grey;
> + case 16: if(is_grey) return STBI_grey_alpha;
> + // fallthrough
> + case 15: if(is_rgb16) *is_rgb16 = 1;
> + return STBI_rgb;
> + case 24: // fallthrough
> + case 32: return bits_per_pixel/8;
> + default: return 0;
> + }
> +}
> +
> +static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + int tga_w, tga_h, tga_comp, tga_image_type, tga_bits_per_pixel, tga_colormap_bpp;
> + int sz, tga_colormap_type;
> + stbi__get8(s); // discard Offset
> + tga_colormap_type = stbi__get8(s); // colormap type
> + if( tga_colormap_type > 1 ) {
> + stbi__rewind(s);
> + return 0; // only RGB or indexed allowed
> + }
> + tga_image_type = stbi__get8(s); // image type
> + if ( tga_colormap_type == 1 ) { // colormapped (paletted) image
> + if (tga_image_type != 1 && tga_image_type != 9) {
> + stbi__rewind(s);
> + return 0;
> + }
> + stbi__skip(s,4); // skip index of first colormap entry and number of entries
> + sz = stbi__get8(s); // check bits per palette color entry
> + if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) {
> + stbi__rewind(s);
> + return 0;
> + }
> + stbi__skip(s,4); // skip image x and y origin
> + tga_colormap_bpp = sz;
> + } else { // "normal" image w/o colormap - only RGB or grey allowed, +/- RLE
> + if ( (tga_image_type != 2) && (tga_image_type != 3) && (tga_image_type != 10) && (tga_image_type != 11) ) {
> + stbi__rewind(s);
> + return 0; // only RGB or grey allowed, +/- RLE
> + }
> + stbi__skip(s,9); // skip colormap specification and image x/y origin
> + tga_colormap_bpp = 0;
> + }
> + tga_w = stbi__get16le(s);
> + if( tga_w < 1 ) {
> + stbi__rewind(s);
> + return 0; // test width
> + }
> + tga_h = stbi__get16le(s);
> + if( tga_h < 1 ) {
> + stbi__rewind(s);
> + return 0; // test height
> + }
> + tga_bits_per_pixel = stbi__get8(s); // bits per pixel
> + stbi__get8(s); // ignore alpha bits
> + if (tga_colormap_bpp != 0) {
> + if((tga_bits_per_pixel != 8) && (tga_bits_per_pixel != 16)) {
> + // when using a colormap, tga_bits_per_pixel is the size of the indexes
> + // I don't think anything but 8 or 16bit indexes makes sense
> + stbi__rewind(s);
> + return 0;
> + }
> + tga_comp = stbi__tga_get_comp(tga_colormap_bpp, 0, NULL);
> + } else {
> + tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3) || (tga_image_type == 11), NULL);
> + }
> + if(!tga_comp) {
> + stbi__rewind(s);
> + return 0;
> + }
> + if (x) *x = tga_w;
> + if (y) *y = tga_h;
> + if (comp) *comp = tga_comp;
> + return 1; // seems to have passed everything
> +}
> +
> +static int stbi__tga_test(stbi__context *s)
> +{
> + int res = 0;
> + int sz, tga_color_type;
> + stbi__get8(s); // discard Offset
> + tga_color_type = stbi__get8(s); // color type
> + if ( tga_color_type > 1 ) goto errorEnd; // only RGB or indexed allowed
> + sz = stbi__get8(s); // image type
> + if ( tga_color_type == 1 ) { // colormapped (paletted) image
> + if (sz != 1 && sz != 9) goto errorEnd; // colortype 1 demands image type 1 or 9
> + stbi__skip(s,4); // skip index of first colormap entry and number of entries
> + sz = stbi__get8(s); // check bits per palette color entry
> + if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) goto errorEnd;
> + stbi__skip(s,4); // skip image x and y origin
> + } else { // "normal" image w/o colormap
> + if ( (sz != 2) && (sz != 3) && (sz != 10) && (sz != 11) ) goto errorEnd; // only RGB or grey allowed, +/- RLE
> + stbi__skip(s,9); // skip colormap specification and image x/y origin
> + }
> + if ( stbi__get16le(s) < 1 ) goto errorEnd; // test width
> + if ( stbi__get16le(s) < 1 ) goto errorEnd; // test height
> + sz = stbi__get8(s); // bits per pixel
> + if ( (tga_color_type == 1) && (sz != 8) && (sz != 16) ) goto errorEnd; // for colormapped images, bpp is size of an index
> + if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) goto errorEnd;
> +
> + res = 1; // if we got this far, everything's good and we can return 1 instead of 0
> +
> +errorEnd:
> + stbi__rewind(s);
> + return res;
> +}
> +
> +// read 16bit value and convert to 24bit RGB
> +static void stbi__tga_read_rgb16(stbi__context *s, stbi_uc* out)
> +{
> + stbi__uint16 px = (stbi__uint16)stbi__get16le(s);
> + stbi__uint16 fiveBitMask = 31;
> + // we have 3 channels with 5bits each
> + int r = (px >> 10) & fiveBitMask;
> + int g = (px >> 5) & fiveBitMask;
> + int b = px & fiveBitMask;
> + // Note that this saves the data in RGB(A) order, so it doesn't need to be swapped later
> + out[0] = (stbi_uc)((r * 255)/31);
> + out[1] = (stbi_uc)((g * 255)/31);
> + out[2] = (stbi_uc)((b * 255)/31);
> +
> + // some people claim that the most significant bit might be used for alpha
> + // (possibly if an alpha-bit is set in the "image descriptor byte")
> + // but that only made 16bit test images completely translucent..
> + // so let's treat all 15 and 16bit TGAs as RGB with no alpha.
> +}
> +
> +static void *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
> +{
> + // read in the TGA header stuff
> + int tga_offset = stbi__get8(s);
> + int tga_indexed = stbi__get8(s);
> + int tga_image_type = stbi__get8(s);
> + int tga_is_RLE = 0;
> + int tga_palette_start = stbi__get16le(s);
> + int tga_palette_len = stbi__get16le(s);
> + int tga_palette_bits = stbi__get8(s);
> + int tga_x_origin = stbi__get16le(s);
> + int tga_y_origin = stbi__get16le(s);
> + int tga_width = stbi__get16le(s);
> + int tga_height = stbi__get16le(s);
> + int tga_bits_per_pixel = stbi__get8(s);
> + int tga_comp, tga_rgb16=0;
> + int tga_inverted = stbi__get8(s);
> + // int tga_alpha_bits = tga_inverted & 15; // the 4 lowest bits - unused (useless?)
> + // image data
> + unsigned char *tga_data;
> + unsigned char *tga_palette = NULL;
> + int i, j;
> + unsigned char raw_data[4] = {0};
> + int RLE_count = 0;
> + int RLE_repeating = 0;
> + int read_next_pixel = 1;
> + STBI_NOTUSED(ri);
> + STBI_NOTUSED(tga_x_origin); // @TODO
> + STBI_NOTUSED(tga_y_origin); // @TODO
> +
> + if (tga_height > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> + if (tga_width > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> +
> + // do a tiny bit of precessing
> + if ( tga_image_type >= 8 )
> + {
> + tga_image_type -= 8;
> + tga_is_RLE = 1;
> + }
> + tga_inverted = 1 - ((tga_inverted >> 5) & 1);
> +
> + // If I'm paletted, then I'll use the number of bits from the palette
> + if ( tga_indexed ) tga_comp = stbi__tga_get_comp(tga_palette_bits, 0, &tga_rgb16);
> + else tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3), &tga_rgb16);
> +
> + if(!tga_comp) // shouldn't really happen, stbi__tga_test() should have ensured basic consistency
> + return stbi__errpuc("bad format", "Can't find out TGA pixelformat");
> +
> + // tga info
> + *x = tga_width;
> + *y = tga_height;
> + if (comp) *comp = tga_comp;
> +
> + if (!stbi__mad3sizes_valid(tga_width, tga_height, tga_comp, 0))
> + return stbi__errpuc("too large", "Corrupt TGA");
> +
> + tga_data = (unsigned char*)stbi__malloc_mad3(tga_width, tga_height, tga_comp, 0);
> + if (!tga_data) return stbi__errpuc("outofmem", "Out of memory");
> +
> + // skip to the data's starting position (offset usually = 0)
> + stbi__skip(s, tga_offset );
> +
> + if ( !tga_indexed && !tga_is_RLE && !tga_rgb16 ) {
> + for (i=0; i < tga_height; ++i) {
> + int row = tga_inverted ? tga_height -i - 1 : i;
> + stbi_uc *tga_row = tga_data + row*tga_width*tga_comp;
> + stbi__getn(s, tga_row, tga_width * tga_comp);
> + }
> + } else {
> + // do I need to load a palette?
> + if ( tga_indexed)
> + {
> + if (tga_palette_len == 0) { /* you have to have at least one entry! */
> + STBI_FREE(tga_data);
> + return stbi__errpuc("bad palette", "Corrupt TGA");
> + }
> +
> + // any data to skip? (offset usually = 0)
> + stbi__skip(s, tga_palette_start );
> + // load the palette
> + tga_palette = (unsigned char*)stbi__malloc_mad2(tga_palette_len, tga_comp, 0);
> + if (!tga_palette) {
> + STBI_FREE(tga_data);
> + return stbi__errpuc("outofmem", "Out of memory");
> + }
> + if (tga_rgb16) {
> + stbi_uc *pal_entry = tga_palette;
> + STBI_ASSERT(tga_comp == STBI_rgb);
> + for (i=0; i < tga_palette_len; ++i) {
> + stbi__tga_read_rgb16(s, pal_entry);
> + pal_entry += tga_comp;
> + }
> + } else if (!stbi__getn(s, tga_palette, tga_palette_len * tga_comp)) {
> + STBI_FREE(tga_data);
> + STBI_FREE(tga_palette);
> + return stbi__errpuc("bad palette", "Corrupt TGA");
> + }
> + }
> + // load the data
> + for (i=0; i < tga_width * tga_height; ++i)
> + {
> + // if I'm in RLE mode, do I need to get a RLE stbi__pngchunk?
> + if ( tga_is_RLE )
> + {
> + if ( RLE_count == 0 )
> + {
> + // yep, get the next byte as a RLE command
> + int RLE_cmd = stbi__get8(s);
> + RLE_count = 1 + (RLE_cmd & 127);
> + RLE_repeating = RLE_cmd >> 7;
> + read_next_pixel = 1;
> + } else if ( !RLE_repeating )
> + {
> + read_next_pixel = 1;
> + }
> + } else
> + {
> + read_next_pixel = 1;
> + }
> + // OK, if I need to read a pixel, do it now
> + if ( read_next_pixel )
> + {
> + // load however much data we did have
> + if ( tga_indexed )
> + {
> + // read in index, then perform the lookup
> + int pal_idx = (tga_bits_per_pixel == 8) ? stbi__get8(s) : stbi__get16le(s);
> + if ( pal_idx >= tga_palette_len ) {
> + // invalid index
> + pal_idx = 0;
> + }
> + pal_idx *= tga_comp;
> + for (j = 0; j < tga_comp; ++j) {
> + raw_data[j] = tga_palette[pal_idx+j];
> + }
> + } else if(tga_rgb16) {
> + STBI_ASSERT(tga_comp == STBI_rgb);
> + stbi__tga_read_rgb16(s, raw_data);
> + } else {
> + // read in the data raw
> + for (j = 0; j < tga_comp; ++j) {
> + raw_data[j] = stbi__get8(s);
> + }
> + }
> + // clear the reading flag for the next pixel
> + read_next_pixel = 0;
> + } // end of reading a pixel
> +
> + // copy data
> + for (j = 0; j < tga_comp; ++j)
> + tga_data[i*tga_comp+j] = raw_data[j];
> +
> + // in case we're in RLE mode, keep counting down
> + --RLE_count;
> + }
> + // do I need to invert the image?
> + if ( tga_inverted )
> + {
> + for (j = 0; j*2 < tga_height; ++j)
> + {
> + int index1 = j * tga_width * tga_comp;
> + int index2 = (tga_height - 1 - j) * tga_width * tga_comp;
> + for (i = tga_width * tga_comp; i > 0; --i)
> + {
> + unsigned char temp = tga_data[index1];
> + tga_data[index1] = tga_data[index2];
> + tga_data[index2] = temp;
> + ++index1;
> + ++index2;
> + }
> + }
> + }
> + // clear my palette, if I had one
> + if ( tga_palette != NULL )
> + {
> + STBI_FREE( tga_palette );
> + }
> + }
> +
> + // swap RGB - if the source data was RGB16, it already is in the right order
> + if (tga_comp >= 3 && !tga_rgb16)
> + {
> + unsigned char* tga_pixel = tga_data;
> + for (i=0; i < tga_width * tga_height; ++i)
> + {
> + unsigned char temp = tga_pixel[0];
> + tga_pixel[0] = tga_pixel[2];
> + tga_pixel[2] = temp;
> + tga_pixel += tga_comp;
> + }
> + }
> +
> + // convert to target component count
> + if (req_comp && req_comp != tga_comp)
> + tga_data = stbi__convert_format(tga_data, tga_comp, req_comp, tga_width, tga_height);
> +
> + // the things I do to get rid of an error message, and yet keep
> + // Microsoft's C compilers happy... [8^(
> + tga_palette_start = tga_palette_len = tga_palette_bits =
> + tga_x_origin = tga_y_origin = 0;
> + STBI_NOTUSED(tga_palette_start);
> + // OK, done
> + return tga_data;
> +}
> +#endif
> +
> +// *************************************************************************************************
> +// Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicolas Schulz, tweaked by STB
> +
> +#ifndef STBI_NO_PSD
> +static int stbi__psd_test(stbi__context *s)
> +{
> + int r = (stbi__get32be(s) == 0x38425053);
> + stbi__rewind(s);
> + return r;
> +}
> +
> +static int stbi__psd_decode_rle(stbi__context *s, stbi_uc *p, int pixelCount)
> +{
> + int count, nleft, len;
> +
> + count = 0;
> + while ((nleft = pixelCount - count) > 0) {
> + len = stbi__get8(s);
> + if (len == 128) {
> + // No-op.
> + } else if (len < 128) {
> + // Copy next len+1 bytes literally.
> + len++;
> + if (len > nleft) return 0; // corrupt data
> + count += len;
> + while (len) {
> + *p = stbi__get8(s);
> + p += 4;
> + len--;
> + }
> + } else if (len > 128) {
> + stbi_uc val;
> + // Next -len+1 bytes in the dest are replicated from next source byte.
> + // (Interpret len as a negative 8-bit int.)
> + len = 257 - len;
> + if (len > nleft) return 0; // corrupt data
> + val = stbi__get8(s);
> + count += len;
> + while (len) {
> + *p = val;
> + p += 4;
> + len--;
> + }
> + }
> + }
> +
> + return 1;
> +}
> +
> +static void *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc)
> +{
> + int pixelCount;
> + int channelCount, compression;
> + int channel, i;
> + int bitdepth;
> + int w,h;
> + stbi_uc *out;
> + STBI_NOTUSED(ri);
> +
> + // Check identifier
> + if (stbi__get32be(s) != 0x38425053) // "8BPS"
> + return stbi__errpuc("not PSD", "Corrupt PSD image");
> +
> + // Check file type version.
> + if (stbi__get16be(s) != 1)
> + return stbi__errpuc("wrong version", "Unsupported version of PSD image");
> +
> + // Skip 6 reserved bytes.
> + stbi__skip(s, 6 );
> +
> + // Read the number of channels (R, G, B, A, etc).
> + channelCount = stbi__get16be(s);
> + if (channelCount < 0 || channelCount > 16)
> + return stbi__errpuc("wrong channel count", "Unsupported number of channels in PSD image");
> +
> + // Read the rows and columns of the image.
> + h = stbi__get32be(s);
> + w = stbi__get32be(s);
> +
> + if (h > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> + if (w > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> +
> + // Make sure the depth is 8 bits.
> + bitdepth = stbi__get16be(s);
> + if (bitdepth != 8 && bitdepth != 16)
> + return stbi__errpuc("unsupported bit depth", "PSD bit depth is not 8 or 16 bit");
> +
> + // Make sure the color mode is RGB.
> + // Valid options are:
> + // 0: Bitmap
> + // 1: Grayscale
> + // 2: Indexed color
> + // 3: RGB color
> + // 4: CMYK color
> + // 7: Multichannel
> + // 8: Duotone
> + // 9: Lab color
> + if (stbi__get16be(s) != 3)
> + return stbi__errpuc("wrong color format", "PSD is not in RGB color format");
> +
> + // Skip the Mode Data. (It's the palette for indexed color; other info for other modes.)
> + stbi__skip(s,stbi__get32be(s) );
> +
> + // Skip the image resources. (resolution, pen tool paths, etc)
> + stbi__skip(s, stbi__get32be(s) );
> +
> + // Skip the reserved data.
> + stbi__skip(s, stbi__get32be(s) );
> +
> + // Find out if the data is compressed.
> + // Known values:
> + // 0: no compression
> + // 1: RLE compressed
> + compression = stbi__get16be(s);
> + if (compression > 1)
> + return stbi__errpuc("bad compression", "PSD has an unknown compression format");
> +
> + // Check size
> + if (!stbi__mad3sizes_valid(4, w, h, 0))
> + return stbi__errpuc("too large", "Corrupt PSD");
> +
> + // Create the destination image.
> +
> + if (!compression && bitdepth == 16 && bpc == 16) {
> + out = (stbi_uc *) stbi__malloc_mad3(8, w, h, 0);
> + ri->bits_per_channel = 16;
> + } else
> + out = (stbi_uc *) stbi__malloc(4 * w*h);
> +
> + if (!out) return stbi__errpuc("outofmem", "Out of memory");
> + pixelCount = w*h;
> +
> + // Initialize the data to zero.
> + //memset( out, 0, pixelCount * 4 );
> +
> + // Finally, the image data.
> + if (compression) {
> + // RLE as used by .PSD and .TIFF
> + // Loop until you get the number of unpacked bytes you are expecting:
> + // Read the next source byte into n.
> + // If n is between 0 and 127 inclusive, copy the next n+1 bytes literally.
> + // Else if n is between -127 and -1 inclusive, copy the next byte -n+1 times.
> + // Else if n is 128, noop.
> + // Endloop
> +
> + // The RLE-compressed data is preceded by a 2-byte data count for each row in the data,
> + // which we're going to just skip.
> + stbi__skip(s, h * channelCount * 2 );
> +
> + // Read the RLE data by channel.
> + for (channel = 0; channel < 4; channel++) {
> + stbi_uc *p;
> +
> + p = out+channel;
> + if (channel >= channelCount) {
> + // Fill this channel with default data.
> + for (i = 0; i < pixelCount; i++, p += 4)
> + *p = (channel == 3 ? 255 : 0);
> + } else {
> + // Read the RLE data.
> + if (!stbi__psd_decode_rle(s, p, pixelCount)) {
> + STBI_FREE(out);
> + return stbi__errpuc("corrupt", "bad RLE data");
> + }
> + }
> + }
> +
> + } else {
> + // We're at the raw image data. It's each channel in order (Red, Green, Blue, Alpha, ...)
> + // where each channel consists of an 8-bit (or 16-bit) value for each pixel in the image.
> +
> + // Read the data by channel.
> + for (channel = 0; channel < 4; channel++) {
> + if (channel >= channelCount) {
> + // Fill this channel with default data.
> + if (bitdepth == 16 && bpc == 16) {
> + stbi__uint16 *q = ((stbi__uint16 *) out) + channel;
> + stbi__uint16 val = channel == 3 ? 65535 : 0;
> + for (i = 0; i < pixelCount; i++, q += 4)
> + *q = val;
> + } else {
> + stbi_uc *p = out+channel;
> + stbi_uc val = channel == 3 ? 255 : 0;
> + for (i = 0; i < pixelCount; i++, p += 4)
> + *p = val;
> + }
> + } else {
> + if (ri->bits_per_channel == 16) { // output bpc
> + stbi__uint16 *q = ((stbi__uint16 *) out) + channel;
> + for (i = 0; i < pixelCount; i++, q += 4)
> + *q = (stbi__uint16) stbi__get16be(s);
> + } else {
> + stbi_uc *p = out+channel;
> + if (bitdepth == 16) { // input bpc
> + for (i = 0; i < pixelCount; i++, p += 4)
> + *p = (stbi_uc) (stbi__get16be(s) >> 8);
> + } else {
> + for (i = 0; i < pixelCount; i++, p += 4)
> + *p = stbi__get8(s);
> + }
> + }
> + }
> + }
> + }
> +
> + // remove weird white matte from PSD
> + if (channelCount >= 4) {
> + if (ri->bits_per_channel == 16) {
> + for (i=0; i < w*h; ++i) {
> + stbi__uint16 *pixel = (stbi__uint16 *) out + 4*i;
> + if (pixel[3] != 0 && pixel[3] != 65535) {
> + float a = pixel[3] / 65535.0f;
> + float ra = 1.0f / a;
> + float inv_a = 65535.0f * (1 - ra);
> + pixel[0] = (stbi__uint16) (pixel[0]*ra + inv_a);
> + pixel[1] = (stbi__uint16) (pixel[1]*ra + inv_a);
> + pixel[2] = (stbi__uint16) (pixel[2]*ra + inv_a);
> + }
> + }
> + } else {
> + for (i=0; i < w*h; ++i) {
> + unsigned char *pixel = out + 4*i;
> + if (pixel[3] != 0 && pixel[3] != 255) {
> + float a = pixel[3] / 255.0f;
> + float ra = 1.0f / a;
> + float inv_a = 255.0f * (1 - ra);
> + pixel[0] = (unsigned char) (pixel[0]*ra + inv_a);
> + pixel[1] = (unsigned char) (pixel[1]*ra + inv_a);
> + pixel[2] = (unsigned char) (pixel[2]*ra + inv_a);
> + }
> + }
> + }
> + }
> +
> + // convert to desired output format
> + if (req_comp && req_comp != 4) {
> + if (ri->bits_per_channel == 16)
> + out = (stbi_uc *) stbi__convert_format16((stbi__uint16 *) out, 4, req_comp, w, h);
> + else
> + out = stbi__convert_format(out, 4, req_comp, w, h);
> + if (out == NULL) return out; // stbi__convert_format frees input on failure
> + }
> +
> + if (comp) *comp = 4;
> + *y = h;
> + *x = w;
> +
> + return out;
> +}
> +#endif
> +
> +// *************************************************************************************************
> +// Softimage PIC loader
> +// by Tom Seddon
> +//
> +// See http://softimage.wiki.softimage.com/index.php/INFO:_PIC_file_format
> +// See http://ozviz.wasp.uwa.edu.au/~pbourke/dataformats/softimagepic/
> +
> +#ifndef STBI_NO_PIC
> +static int stbi__pic_is4(stbi__context *s,const char *str)
> +{
> + int i;
> + for (i=0; i<4; ++i)
> + if (stbi__get8(s) != (stbi_uc)str[i])
> + return 0;
> +
> + return 1;
> +}
> +
> +static int stbi__pic_test_core(stbi__context *s)
> +{
> + int i;
> +
> + if (!stbi__pic_is4(s,"\x53\x80\xF6\x34"))
> + return 0;
> +
> + for(i=0;i<84;++i)
> + stbi__get8(s);
> +
> + if (!stbi__pic_is4(s,"PICT"))
> + return 0;
> +
> + return 1;
> +}
> +
> +typedef struct
> +{
> + stbi_uc size,type,channel;
> +} stbi__pic_packet;
> +
> +static stbi_uc *stbi__readval(stbi__context *s, int channel, stbi_uc *dest)
> +{
> + int mask=0x80, i;
> +
> + for (i=0; i<4; ++i, mask>>=1) {
> + if (channel & mask) {
> + if (stbi__at_eof(s)) return stbi__errpuc("bad file","PIC file too short");
> + dest[i]=stbi__get8(s);
> + }
> + }
> +
> + return dest;
> +}
> +
> +static void stbi__copyval(int channel,stbi_uc *dest,const stbi_uc *src)
> +{
> + int mask=0x80,i;
> +
> + for (i=0;i<4; ++i, mask>>=1)
> + if (channel&mask)
> + dest[i]=src[i];
> +}
> +
> +static stbi_uc *stbi__pic_load_core(stbi__context *s,int width,int height,int *comp, stbi_uc *result)
> +{
> + int act_comp=0,num_packets=0,y,chained;
> + stbi__pic_packet packets[10];
> +
> + // this will (should...) cater for even some bizarre stuff like having data
> + // for the same channel in multiple packets.
> + do {
> + stbi__pic_packet *packet;
> +
> + if (num_packets==sizeof(packets)/sizeof(packets[0]))
> + return stbi__errpuc("bad format","too many packets");
> +
> + packet = &packets[num_packets++];
> +
> + chained = stbi__get8(s);
> + packet->size = stbi__get8(s);
> + packet->type = stbi__get8(s);
> + packet->channel = stbi__get8(s);
> +
> + act_comp |= packet->channel;
> +
> + if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (reading packets)");
> + if (packet->size != 8) return stbi__errpuc("bad format","packet isn't 8bpp");
> + } while (chained);
> +
> + *comp = (act_comp & 0x10 ? 4 : 3); // has alpha channel?
> +
> + for(y=0; y<height; ++y) {
> + int packet_idx;
> +
> + for(packet_idx=0; packet_idx < num_packets; ++packet_idx) {
> + stbi__pic_packet *packet = &packets[packet_idx];
> + stbi_uc *dest = result+y*width*4;
> +
> + switch (packet->type) {
> + default:
> + return stbi__errpuc("bad format","packet has bad compression type");
> +
> + case 0: {//uncompressed
> + int x;
> +
> + for(x=0;x<width;++x, dest+=4)
> + if (!stbi__readval(s,packet->channel,dest))
> + return 0;
> + break;
> + }
> +
> + case 1://Pure RLE
> + {
> + int left=width, i;
> +
> + while (left>0) {
> + stbi_uc count,value[4];
> +
> + count=stbi__get8(s);
> + if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (pure read count)");
> +
> + if (count > left)
> + count = (stbi_uc) left;
> +
> + if (!stbi__readval(s,packet->channel,value)) return 0;
> +
> + for(i=0; i<count; ++i,dest+=4)
> + stbi__copyval(packet->channel,dest,value);
> + left -= count;
> + }
> + }
> + break;
> +
> + case 2: {//Mixed RLE
> + int left=width;
> + while (left>0) {
> + int count = stbi__get8(s), i;
> + if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (mixed read count)");
> +
> + if (count >= 128) { // Repeated
> + stbi_uc value[4];
> +
> + if (count==128)
> + count = stbi__get16be(s);
> + else
> + count -= 127;
> + if (count > left)
> + return stbi__errpuc("bad file","scanline overrun");
> +
> + if (!stbi__readval(s,packet->channel,value))
> + return 0;
> +
> + for(i=0;i<count;++i, dest += 4)
> + stbi__copyval(packet->channel,dest,value);
> + } else { // Raw
> + ++count;
> + if (count>left) return stbi__errpuc("bad file","scanline overrun");
> +
> + for(i=0;i<count;++i, dest+=4)
> + if (!stbi__readval(s,packet->channel,dest))
> + return 0;
> + }
> + left-=count;
> + }
> + break;
> + }
> + }
> + }
> + }
> +
> + return result;
> +}
> +
> +static void *stbi__pic_load(stbi__context *s,int *px,int *py,int *comp,int req_comp, stbi__result_info *ri)
> +{
> + stbi_uc *result;
> + int i, x,y, internal_comp;
> + STBI_NOTUSED(ri);
> +
> + if (!comp) comp = &internal_comp;
> +
> + for (i=0; i<92; ++i)
> + stbi__get8(s);
> +
> + x = stbi__get16be(s);
> + y = stbi__get16be(s);
> +
> + if (y > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> + if (x > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> +
> + if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (pic header)");
> + if (!stbi__mad3sizes_valid(x, y, 4, 0)) return stbi__errpuc("too large", "PIC image too large to decode");
> +
> + stbi__get32be(s); //skip `ratio'
> + stbi__get16be(s); //skip `fields'
> + stbi__get16be(s); //skip `pad'
> +
> + // intermediate buffer is RGBA
> + result = (stbi_uc *) stbi__malloc_mad3(x, y, 4, 0);
> + memset(result, 0xff, x*y*4);
> +
> + if (!stbi__pic_load_core(s,x,y,comp, result)) {
> + STBI_FREE(result);
> + result=0;
> + }
> + *px = x;
> + *py = y;
> + if (req_comp == 0) req_comp = *comp;
> + result=stbi__convert_format(result,4,req_comp,x,y);
> +
> + return result;
> +}
> +
> +static int stbi__pic_test(stbi__context *s)
> +{
> + int r = stbi__pic_test_core(s);
> + stbi__rewind(s);
> + return r;
> +}
> +#endif
> +
> +// *************************************************************************************************
> +// GIF loader -- public domain by Jean-Marc Lienher -- simplified/shrunk by stb
> +
> +#ifndef STBI_NO_GIF
> +typedef struct
> +{
> + stbi__int16 prefix;
> + stbi_uc first;
> + stbi_uc suffix;
> +} stbi__gif_lzw;
> +
> +typedef struct
> +{
> + int w,h;
> + stbi_uc *out; // output buffer (always 4 components)
> + stbi_uc *background; // The current "background" as far as a gif is concerned
> + stbi_uc *history;
> + int flags, bgindex, ratio, transparent, eflags;
> + stbi_uc pal[256][4];
> + stbi_uc lpal[256][4];
> + stbi__gif_lzw codes[8192];
> + stbi_uc *color_table;
> + int parse, step;
> + int lflags;
> + int start_x, start_y;
> + int max_x, max_y;
> + int cur_x, cur_y;
> + int line_size;
> + int delay;
> +} stbi__gif;
> +
> +static int stbi__gif_test_raw(stbi__context *s)
> +{
> + int sz;
> + if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8') return 0;
> + sz = stbi__get8(s);
> + if (sz != '9' && sz != '7') return 0;
> + if (stbi__get8(s) != 'a') return 0;
> + return 1;
> +}
> +
> +static int stbi__gif_test(stbi__context *s)
> +{
> + int r = stbi__gif_test_raw(s);
> + stbi__rewind(s);
> + return r;
> +}
> +
> +static void stbi__gif_parse_colortable(stbi__context *s, stbi_uc pal[256][4], int num_entries, int transp)
> +{
> + int i;
> + for (i=0; i < num_entries; ++i) {
> + pal[i][2] = stbi__get8(s);
> + pal[i][1] = stbi__get8(s);
> + pal[i][0] = stbi__get8(s);
> + pal[i][3] = transp == i ? 0 : 255;
> + }
> +}
> +
> +static int stbi__gif_header(stbi__context *s, stbi__gif *g, int *comp, int is_info)
> +{
> + stbi_uc version;
> + if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8')
> + return stbi__err("not GIF", "Corrupt GIF");
> +
> + version = stbi__get8(s);
> + if (version != '7' && version != '9') return stbi__err("not GIF", "Corrupt GIF");
> + if (stbi__get8(s) != 'a') return stbi__err("not GIF", "Corrupt GIF");
> +
> + stbi__g_failure_reason = "";
> + g->w = stbi__get16le(s);
> + g->h = stbi__get16le(s);
> + g->flags = stbi__get8(s);
> + g->bgindex = stbi__get8(s);
> + g->ratio = stbi__get8(s);
> + g->transparent = -1;
> +
> + if (g->w > STBI_MAX_DIMENSIONS) return stbi__err("too large","Very large image (corrupt?)");
> + if (g->h > STBI_MAX_DIMENSIONS) return stbi__err("too large","Very large image (corrupt?)");
> +
> + if (comp != 0) *comp = 4; // can't actually tell whether it's 3 or 4 until we parse the comments
> +
> + if (is_info) return 1;
> +
> + if (g->flags & 0x80)
> + stbi__gif_parse_colortable(s,g->pal, 2 << (g->flags & 7), -1);
> +
> + return 1;
> +}
> +
> +static int stbi__gif_info_raw(stbi__context *s, int *x, int *y, int *comp)
> +{
> + stbi__gif* g = (stbi__gif*) stbi__malloc(sizeof(stbi__gif));
> + if (!stbi__gif_header(s, g, comp, 1)) {
> + STBI_FREE(g);
> + stbi__rewind( s );
> + return 0;
> + }
> + if (x) *x = g->w;
> + if (y) *y = g->h;
> + STBI_FREE(g);
> + return 1;
> +}
> +
> +static void stbi__out_gif_code(stbi__gif *g, stbi__uint16 code)
> +{
> + stbi_uc *p, *c;
> + int idx;
> +
> + // recurse to decode the prefixes, since the linked-list is backwards,
> + // and working backwards through an interleaved image would be nasty
> + if (g->codes[code].prefix >= 0)
> + stbi__out_gif_code(g, g->codes[code].prefix);
> +
> + if (g->cur_y >= g->max_y) return;
> +
> + idx = g->cur_x + g->cur_y;
> + p = &g->out[idx];
> + g->history[idx / 4] = 1;
> +
> + c = &g->color_table[g->codes[code].suffix * 4];
> + if (c[3] > 128) { // don't render transparent pixels;
> + p[0] = c[2];
> + p[1] = c[1];
> + p[2] = c[0];
> + p[3] = c[3];
> + }
> + g->cur_x += 4;
> +
> + if (g->cur_x >= g->max_x) {
> + g->cur_x = g->start_x;
> + g->cur_y += g->step;
> +
> + while (g->cur_y >= g->max_y && g->parse > 0) {
> + g->step = (1 << g->parse) * g->line_size;
> + g->cur_y = g->start_y + (g->step >> 1);
> + --g->parse;
> + }
> + }
> +}
> +
> +static stbi_uc *stbi__process_gif_raster(stbi__context *s, stbi__gif *g)
> +{
> + stbi_uc lzw_cs;
> + stbi__int32 len, init_code;
> + stbi__uint32 first;
> + stbi__int32 codesize, codemask, avail, oldcode, bits, valid_bits, clear;
> + stbi__gif_lzw *p;
> +
> + lzw_cs = stbi__get8(s);
> + if (lzw_cs > 12) return NULL;
> + clear = 1 << lzw_cs;
> + first = 1;
> + codesize = lzw_cs + 1;
> + codemask = (1 << codesize) - 1;
> + bits = 0;
> + valid_bits = 0;
> + for (init_code = 0; init_code < clear; init_code++) {
> + g->codes[init_code].prefix = -1;
> + g->codes[init_code].first = (stbi_uc) init_code;
> + g->codes[init_code].suffix = (stbi_uc) init_code;
> + }
> +
> + // support no starting clear code
> + avail = clear+2;
> + oldcode = -1;
> +
> + len = 0;
> + for(;;) {
> + if (valid_bits < codesize) {
> + if (len == 0) {
> + len = stbi__get8(s); // start new block
> + if (len == 0)
> + return g->out;
> + }
> + --len;
> + bits |= (stbi__int32) stbi__get8(s) << valid_bits;
> + valid_bits += 8;
> + } else {
> + stbi__int32 code = bits & codemask;
> + bits >>= codesize;
> + valid_bits -= codesize;
> + // @OPTIMIZE: is there some way we can accelerate the non-clear path?
> + if (code == clear) { // clear code
> + codesize = lzw_cs + 1;
> + codemask = (1 << codesize) - 1;
> + avail = clear + 2;
> + oldcode = -1;
> + first = 0;
> + } else if (code == clear + 1) { // end of stream code
> + stbi__skip(s, len);
> + while ((len = stbi__get8(s)) > 0)
> + stbi__skip(s,len);
> + return g->out;
> + } else if (code <= avail) {
> + if (first) {
> + return stbi__errpuc("no clear code", "Corrupt GIF");
> + }
> +
> + if (oldcode >= 0) {
> + p = &g->codes[avail++];
> + if (avail > 8192) {
> + return stbi__errpuc("too many codes", "Corrupt GIF");
> + }
> +
> + p->prefix = (stbi__int16) oldcode;
> + p->first = g->codes[oldcode].first;
> + p->suffix = (code == avail) ? p->first : g->codes[code].first;
> + } else if (code == avail)
> + return stbi__errpuc("illegal code in raster", "Corrupt GIF");
> +
> + stbi__out_gif_code(g, (stbi__uint16) code);
> +
> + if ((avail & codemask) == 0 && avail <= 0x0FFF) {
> + codesize++;
> + codemask = (1 << codesize) - 1;
> + }
> +
> + oldcode = code;
> + } else {
> + return stbi__errpuc("illegal code in raster", "Corrupt GIF");
> + }
> + }
> + }
> +}
> +
> +// this function is designed to support animated gifs, although stb_image doesn't support it
> +// two back is the image from two frames ago, used for a very specific disposal format
> +static stbi_uc *stbi__gif_load_next(stbi__context *s, stbi__gif *g, int *comp, int req_comp, stbi_uc *two_back)
> +{
> + int dispose;
> + int first_frame;
> + int pi;
> + int pcount;
> + STBI_NOTUSED(req_comp);
> +
> + // on first frame, any non-written pixels get the background colour (non-transparent)
> + first_frame = 0;
> + if (g->out == 0) {
> + if (!stbi__gif_header(s, g, comp,0)) return 0; // stbi__g_failure_reason set by stbi__gif_header
> + if (!stbi__mad3sizes_valid(4, g->w, g->h, 0))
> + return stbi__errpuc("too large", "GIF image is too large");
> + pcount = g->w * g->h;
> + g->out = (stbi_uc *) stbi__malloc(4 * pcount);
> + g->background = (stbi_uc *) stbi__malloc(4 * pcount);
> + g->history = (stbi_uc *) stbi__malloc(pcount);
> + if (!g->out || !g->background || !g->history)
> + return stbi__errpuc("outofmem", "Out of memory");
> +
> + // image is treated as "transparent" at the start - ie, nothing overwrites the current background;
> + // background colour is only used for pixels that are not rendered first frame, after that "background"
> + // color refers to the color that was there the previous frame.
> + memset(g->out, 0x00, 4 * pcount);
> + memset(g->background, 0x00, 4 * pcount); // state of the background (starts transparent)
> + memset(g->history, 0x00, pcount); // pixels that were affected previous frame
> + first_frame = 1;
> + } else {
> + // second frame - how do we dispose of the previous one?
> + dispose = (g->eflags & 0x1C) >> 2;
> + pcount = g->w * g->h;
> +
> + if ((dispose == 3) && (two_back == 0)) {
> + dispose = 2; // if I don't have an image to revert back to, default to the old background
> + }
> +
> + if (dispose == 3) { // use previous graphic
> + for (pi = 0; pi < pcount; ++pi) {
> + if (g->history[pi]) {
> + memcpy( &g->out[pi * 4], &two_back[pi * 4], 4 );
> + }
> + }
> + } else if (dispose == 2) {
> + // restore what was changed last frame to background before that frame;
> + for (pi = 0; pi < pcount; ++pi) {
> + if (g->history[pi]) {
> + memcpy( &g->out[pi * 4], &g->background[pi * 4], 4 );
> + }
> + }
> + } else {
> + // This is a non-disposal case eithe way, so just
> + // leave the pixels as is, and they will become the new background
> + // 1: do not dispose
> + // 0: not specified.
> + }
> +
> + // background is what out is after the undoing of the previou frame;
> + memcpy( g->background, g->out, 4 * g->w * g->h );
> + }
> +
> + // clear my history;
> + memset( g->history, 0x00, g->w * g->h ); // pixels that were affected previous frame
> +
> + for (;;) {
> + int tag = stbi__get8(s);
> + switch (tag) {
> + case 0x2C: /* Image Descriptor */
> + {
> + stbi__int32 x, y, w, h;
> + stbi_uc *o;
> +
> + x = stbi__get16le(s);
> + y = stbi__get16le(s);
> + w = stbi__get16le(s);
> + h = stbi__get16le(s);
> + if (((x + w) > (g->w)) || ((y + h) > (g->h)))
> + return stbi__errpuc("bad Image Descriptor", "Corrupt GIF");
> +
> + g->line_size = g->w * 4;
> + g->start_x = x * 4;
> + g->start_y = y * g->line_size;
> + g->max_x = g->start_x + w * 4;
> + g->max_y = g->start_y + h * g->line_size;
> + g->cur_x = g->start_x;
> + g->cur_y = g->start_y;
> +
> + // if the width of the specified rectangle is 0, that means
> + // we may not see *any* pixels or the image is malformed;
> + // to make sure this is caught, move the current y down to
> + // max_y (which is what out_gif_code checks).
> + if (w == 0)
> + g->cur_y = g->max_y;
> +
> + g->lflags = stbi__get8(s);
> +
> + if (g->lflags & 0x40) {
> + g->step = 8 * g->line_size; // first interlaced spacing
> + g->parse = 3;
> + } else {
> + g->step = g->line_size;
> + g->parse = 0;
> + }
> +
> + if (g->lflags & 0x80) {
> + stbi__gif_parse_colortable(s,g->lpal, 2 << (g->lflags & 7), g->eflags & 0x01 ? g->transparent : -1);
> + g->color_table = (stbi_uc *) g->lpal;
> + } else if (g->flags & 0x80) {
> + g->color_table = (stbi_uc *) g->pal;
> + } else
> + return stbi__errpuc("missing color table", "Corrupt GIF");
> +
> + o = stbi__process_gif_raster(s, g);
> + if (!o) return NULL;
> +
> + // if this was the first frame,
> + pcount = g->w * g->h;
> + if (first_frame && (g->bgindex > 0)) {
> + // if first frame, any pixel not drawn to gets the background color
> + for (pi = 0; pi < pcount; ++pi) {
> + if (g->history[pi] == 0) {
> + g->pal[g->bgindex][3] = 255; // just in case it was made transparent, undo that; It will be reset next frame if need be;
> + memcpy( &g->out[pi * 4], &g->pal[g->bgindex], 4 );
> + }
> + }
> + }
> +
> + return o;
> + }
> +
> + case 0x21: // Comment Extension.
> + {
> + int len;
> + int ext = stbi__get8(s);
> + if (ext == 0xF9) { // Graphic Control Extension.
> + len = stbi__get8(s);
> + if (len == 4) {
> + g->eflags = stbi__get8(s);
> + g->delay = 10 * stbi__get16le(s); // delay - 1/100th of a second, saving as 1/1000ths.
> +
> + // unset old transparent
> + if (g->transparent >= 0) {
> + g->pal[g->transparent][3] = 255;
> + }
> + if (g->eflags & 0x01) {
> + g->transparent = stbi__get8(s);
> + if (g->transparent >= 0) {
> + g->pal[g->transparent][3] = 0;
> + }
> + } else {
> + // don't need transparent
> + stbi__skip(s, 1);
> + g->transparent = -1;
> + }
> + } else {
> + stbi__skip(s, len);
> + break;
> + }
> + }
> + while ((len = stbi__get8(s)) != 0) {
> + stbi__skip(s, len);
> + }
> + break;
> + }
> +
> + case 0x3B: // gif stream termination code
> + return (stbi_uc *) s; // using '1' causes warning on some compilers
> +
> + default:
> + return stbi__errpuc("unknown code", "Corrupt GIF");
> + }
> + }
> +}
> +
> +static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y, int *z, int *comp, int req_comp)
> +{
> + if (stbi__gif_test(s)) {
> + int layers = 0;
> + stbi_uc *u = 0;
> + stbi_uc *out = 0;
> + stbi_uc *two_back = 0;
> + stbi__gif g;
> + int stride;
> + memset(&g, 0, sizeof(g));
> + if (delays) {
> + *delays = 0;
> + }
> +
> + do {
> + u = stbi__gif_load_next(s, &g, comp, req_comp, two_back);
> + if (u == (stbi_uc *) s) u = 0; // end of animated gif marker
> +
> + if (u) {
> + *x = g.w;
> + *y = g.h;
> + ++layers;
> + stride = g.w * g.h * 4;
> +
> + if (out) {
> + void *tmp = (stbi_uc*) STBI_REALLOC_SIZED( out, 0, layers * stride );
> + if (NULL == tmp) {
> + STBI_FREE(g.out);
> + STBI_FREE(g.history);
> + STBI_FREE(g.background);
> + return stbi__errpuc("outofmem", "Out of memory");
> + }
> + else {
> + out = (stbi_uc*) tmp;
> + }
> +
> + if (delays) {
> + *delays = (int*) STBI_REALLOC_SIZED( *delays, 0, sizeof(int) * layers );
> + }
> + } else {
> + out = (stbi_uc*)stbi__malloc( layers * stride );
> + if (delays) {
> + *delays = (int*) stbi__malloc( layers * sizeof(int) );
> + }
> + }
> + memcpy( out + ((layers - 1) * stride), u, stride );
> + if (layers >= 2) {
> + two_back = out - 2 * stride;
> + }
> +
> + if (delays) {
> + (*delays)[layers - 1U] = g.delay;
> + }
> + }
> + } while (u != 0);
> +
> + // free temp buffer;
> + STBI_FREE(g.out);
> + STBI_FREE(g.history);
> + STBI_FREE(g.background);
> +
> + // do the final conversion after loading everything;
> + if (req_comp && req_comp != 4)
> + out = stbi__convert_format(out, 4, req_comp, layers * g.w, g.h);
> +
> + *z = layers;
> + return out;
> + } else {
> + return stbi__errpuc("not GIF", "Image was not as a gif type.");
> + }
> +}
> +
> +static void *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
> +{
> + stbi_uc *u = 0;
> + stbi__gif g;
> + memset(&g, 0, sizeof(g));
> + STBI_NOTUSED(ri);
> +
> + u = stbi__gif_load_next(s, &g, comp, req_comp, 0);
> + if (u == (stbi_uc *) s) u = 0; // end of animated gif marker
> + if (u) {
> + *x = g.w;
> + *y = g.h;
> +
> + // moved conversion to after successful load so that the same
> + // can be done for multiple frames.
> + if (req_comp && req_comp != 4)
> + u = stbi__convert_format(u, 4, req_comp, g.w, g.h);
> + } else if (g.out) {
> + // if there was an error and we allocated an image buffer, free it!
> + STBI_FREE(g.out);
> + }
> +
> + // free buffers needed for multiple frame loading;
> + STBI_FREE(g.history);
> + STBI_FREE(g.background);
> +
> + return u;
> +}
> +
> +static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + return stbi__gif_info_raw(s,x,y,comp);
> +}
> +#endif
> +
> +// *************************************************************************************************
> +// Radiance RGBE HDR loader
> +// originally by Nicolas Schulz
> +#ifndef STBI_NO_HDR
> +static int stbi__hdr_test_core(stbi__context *s, const char *signature)
> +{
> + int i;
> + for (i=0; signature[i]; ++i)
> + if (stbi__get8(s) != signature[i])
> + return 0;
> + stbi__rewind(s);
> + return 1;
> +}
> +
> +static int stbi__hdr_test(stbi__context* s)
> +{
> + int r = stbi__hdr_test_core(s, "#?RADIANCE\n");
> + stbi__rewind(s);
> + if(!r) {
> + r = stbi__hdr_test_core(s, "#?RGBE\n");
> + stbi__rewind(s);
> + }
> + return r;
> +}
> +
> +#define STBI__HDR_BUFLEN 1024
> +static char *stbi__hdr_gettoken(stbi__context *z, char *buffer)
> +{
> + int len=0;
> + char c = '\0';
> +
> + c = (char) stbi__get8(z);
> +
> + while (!stbi__at_eof(z) && c != '\n') {
> + buffer[len++] = c;
> + if (len == STBI__HDR_BUFLEN-1) {
> + // flush to end of line
> + while (!stbi__at_eof(z) && stbi__get8(z) != '\n')
> + ;
> + break;
> + }
> + c = (char) stbi__get8(z);
> + }
> +
> + buffer[len] = 0;
> + return buffer;
> +}
> +
> +static void stbi__hdr_convert(float *output, stbi_uc *input, int req_comp)
> +{
> + if ( input[3] != 0 ) {
> + float f1;
> + // Exponent
> + f1 = (float) ldexp(1.0f, input[3] - (int)(128 + 8));
> + if (req_comp <= 2)
> + output[0] = (input[0] + input[1] + input[2]) * f1 / 3;
> + else {
> + output[0] = input[0] * f1;
> + output[1] = input[1] * f1;
> + output[2] = input[2] * f1;
> + }
> + if (req_comp == 2) output[1] = 1;
> + if (req_comp == 4) output[3] = 1;
> + } else {
> + switch (req_comp) {
> + case 4: output[3] = 1; /* fallthrough */
> + case 3: output[0] = output[1] = output[2] = 0;
> + break;
> + case 2: output[1] = 1; /* fallthrough */
> + case 1: output[0] = 0;
> + break;
> + }
> + }
> +}
> +
> +static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
> +{
> + char buffer[STBI__HDR_BUFLEN];
> + char *token;
> + int valid = 0;
> + int width, height;
> + stbi_uc *scanline;
> + float *hdr_data;
> + int len;
> + unsigned char count, value;
> + int i, j, k, c1,c2, z;
> + const char *headerToken;
> + STBI_NOTUSED(ri);
> +
> + // Check identifier
> + headerToken = stbi__hdr_gettoken(s,buffer);
> + if (strcmp(headerToken, "#?RADIANCE") != 0 && strcmp(headerToken, "#?RGBE") != 0)
> + return stbi__errpf("not HDR", "Corrupt HDR image");
> +
> + // Parse header
> + for(;;) {
> + token = stbi__hdr_gettoken(s,buffer);
> + if (token[0] == 0) break;
> + if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1;
> + }
> +
> + if (!valid) return stbi__errpf("unsupported format", "Unsupported HDR format");
> +
> + // Parse width and height
> + // can't use sscanf() if we're not using stdio!
> + token = stbi__hdr_gettoken(s,buffer);
> + if (strncmp(token, "-Y ", 3)) return stbi__errpf("unsupported data layout", "Unsupported HDR format");
> + token += 3;
> + height = (int) strtol(token, &token, 10);
> + while (*token == ' ') ++token;
> + if (strncmp(token, "+X ", 3)) return stbi__errpf("unsupported data layout", "Unsupported HDR format");
> + token += 3;
> + width = (int) strtol(token, NULL, 10);
> +
> + if (height > STBI_MAX_DIMENSIONS) return stbi__errpf("too large","Very large image (corrupt?)");
> + if (width > STBI_MAX_DIMENSIONS) return stbi__errpf("too large","Very large image (corrupt?)");
> +
> + *x = width;
> + *y = height;
> +
> + if (comp) *comp = 3;
> + if (req_comp == 0) req_comp = 3;
> +
> + if (!stbi__mad4sizes_valid(width, height, req_comp, sizeof(float), 0))
> + return stbi__errpf("too large", "HDR image is too large");
> +
> + // Read data
> + hdr_data = (float *) stbi__malloc_mad4(width, height, req_comp, sizeof(float), 0);
> + if (!hdr_data)
> + return stbi__errpf("outofmem", "Out of memory");
> +
> + // Load image data
> + // image data is stored as some number of sca
> + if ( width < 8 || width >= 32768) {
> + // Read flat data
> + for (j=0; j < height; ++j) {
> + for (i=0; i < width; ++i) {
> + stbi_uc rgbe[4];
> + main_decode_loop:
> + stbi__getn(s, rgbe, 4);
> + stbi__hdr_convert(hdr_data + j * width * req_comp + i * req_comp, rgbe, req_comp);
> + }
> + }
> + } else {
> + // Read RLE-encoded data
> + scanline = NULL;
> +
> + for (j = 0; j < height; ++j) {
> + c1 = stbi__get8(s);
> + c2 = stbi__get8(s);
> + len = stbi__get8(s);
> + if (c1 != 2 || c2 != 2 || (len & 0x80)) {
> + // not run-length encoded, so we have to actually use THIS data as a decoded
> + // pixel (note this can't be a valid pixel--one of RGB must be >= 128)
> + stbi_uc rgbe[4];
> + rgbe[0] = (stbi_uc) c1;
> + rgbe[1] = (stbi_uc) c2;
> + rgbe[2] = (stbi_uc) len;
> + rgbe[3] = (stbi_uc) stbi__get8(s);
> + stbi__hdr_convert(hdr_data, rgbe, req_comp);
> + i = 1;
> + j = 0;
> + STBI_FREE(scanline);
> + goto main_decode_loop; // yes, this makes no sense
> + }
> + len <<= 8;
> + len |= stbi__get8(s);
> + if (len != width) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("invalid decoded scanline length", "corrupt HDR"); }
> + if (scanline == NULL) {
> + scanline = (stbi_uc *) stbi__malloc_mad2(width, 4, 0);
> + if (!scanline) {
> + STBI_FREE(hdr_data);
> + return stbi__errpf("outofmem", "Out of memory");
> + }
> + }
> +
> + for (k = 0; k < 4; ++k) {
> + int nleft;
> + i = 0;
> + while ((nleft = width - i) > 0) {
> + count = stbi__get8(s);
> + if (count > 128) {
> + // Run
> + value = stbi__get8(s);
> + count -= 128;
> + if (count > nleft) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("corrupt", "bad RLE data in HDR"); }
> + for (z = 0; z < count; ++z)
> + scanline[i++ * 4 + k] = value;
> + } else {
> + // Dump
> + if (count > nleft) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("corrupt", "bad RLE data in HDR"); }
> + for (z = 0; z < count; ++z)
> + scanline[i++ * 4 + k] = stbi__get8(s);
> + }
> + }
> + }
> + for (i=0; i < width; ++i)
> + stbi__hdr_convert(hdr_data+(j*width + i)*req_comp, scanline + i*4, req_comp);
> + }
> + if (scanline)
> + STBI_FREE(scanline);
> + }
> +
> + return hdr_data;
> +}
> +
> +static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + char buffer[STBI__HDR_BUFLEN];
> + char *token;
> + int valid = 0;
> + int dummy;
> +
> + if (!x) x = &dummy;
> + if (!y) y = &dummy;
> + if (!comp) comp = &dummy;
> +
> + if (stbi__hdr_test(s) == 0) {
> + stbi__rewind( s );
> + return 0;
> + }
> +
> + for(;;) {
> + token = stbi__hdr_gettoken(s,buffer);
> + if (token[0] == 0) break;
> + if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1;
> + }
> +
> + if (!valid) {
> + stbi__rewind( s );
> + return 0;
> + }
> + token = stbi__hdr_gettoken(s,buffer);
> + if (strncmp(token, "-Y ", 3)) {
> + stbi__rewind( s );
> + return 0;
> + }
> + token += 3;
> + *y = (int) strtol(token, &token, 10);
> + while (*token == ' ') ++token;
> + if (strncmp(token, "+X ", 3)) {
> + stbi__rewind( s );
> + return 0;
> + }
> + token += 3;
> + *x = (int) strtol(token, NULL, 10);
> + *comp = 3;
> + return 1;
> +}
> +#endif // STBI_NO_HDR
> +
> +#ifndef STBI_NO_BMP
> +static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + void *p;
> + stbi__bmp_data info;
> +
> + info.all_a = 255;
> + p = stbi__bmp_parse_header(s, &info);
> + stbi__rewind( s );
> + if (p == NULL)
> + return 0;
> + if (x) *x = s->img_x;
> + if (y) *y = s->img_y;
> + if (comp) {
> + if (info.bpp == 24 && info.ma == 0xff000000)
> + *comp = 3;
> + else
> + *comp = info.ma ? 4 : 3;
> + }
> + return 1;
> +}
> +#endif
> +
> +#ifndef STBI_NO_PSD
> +static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + int channelCount, dummy, depth;
> + if (!x) x = &dummy;
> + if (!y) y = &dummy;
> + if (!comp) comp = &dummy;
> + if (stbi__get32be(s) != 0x38425053) {
> + stbi__rewind( s );
> + return 0;
> + }
> + if (stbi__get16be(s) != 1) {
> + stbi__rewind( s );
> + return 0;
> + }
> + stbi__skip(s, 6);
> + channelCount = stbi__get16be(s);
> + if (channelCount < 0 || channelCount > 16) {
> + stbi__rewind( s );
> + return 0;
> + }
> + *y = stbi__get32be(s);
> + *x = stbi__get32be(s);
> + depth = stbi__get16be(s);
> + if (depth != 8 && depth != 16) {
> + stbi__rewind( s );
> + return 0;
> + }
> + if (stbi__get16be(s) != 3) {
> + stbi__rewind( s );
> + return 0;
> + }
> + *comp = 4;
> + return 1;
> +}
> +
> +static int stbi__psd_is16(stbi__context *s)
> +{
> + int channelCount, depth;
> + if (stbi__get32be(s) != 0x38425053) {
> + stbi__rewind( s );
> + return 0;
> + }
> + if (stbi__get16be(s) != 1) {
> + stbi__rewind( s );
> + return 0;
> + }
> + stbi__skip(s, 6);
> + channelCount = stbi__get16be(s);
> + if (channelCount < 0 || channelCount > 16) {
> + stbi__rewind( s );
> + return 0;
> + }
> + (void) stbi__get32be(s);
> + (void) stbi__get32be(s);
> + depth = stbi__get16be(s);
> + if (depth != 16) {
> + stbi__rewind( s );
> + return 0;
> + }
> + return 1;
> +}
> +#endif
> +
> +#ifndef STBI_NO_PIC
> +static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + int act_comp=0,num_packets=0,chained,dummy;
> + stbi__pic_packet packets[10];
> +
> + if (!x) x = &dummy;
> + if (!y) y = &dummy;
> + if (!comp) comp = &dummy;
> +
> + if (!stbi__pic_is4(s,"\x53\x80\xF6\x34")) {
> + stbi__rewind(s);
> + return 0;
> + }
> +
> + stbi__skip(s, 88);
> +
> + *x = stbi__get16be(s);
> + *y = stbi__get16be(s);
> + if (stbi__at_eof(s)) {
> + stbi__rewind( s);
> + return 0;
> + }
> + if ( (*x) != 0 && (1 << 28) / (*x) < (*y)) {
> + stbi__rewind( s );
> + return 0;
> + }
> +
> + stbi__skip(s, 8);
> +
> + do {
> + stbi__pic_packet *packet;
> +
> + if (num_packets==sizeof(packets)/sizeof(packets[0]))
> + return 0;
> +
> + packet = &packets[num_packets++];
> + chained = stbi__get8(s);
> + packet->size = stbi__get8(s);
> + packet->type = stbi__get8(s);
> + packet->channel = stbi__get8(s);
> + act_comp |= packet->channel;
> +
> + if (stbi__at_eof(s)) {
> + stbi__rewind( s );
> + return 0;
> + }
> + if (packet->size != 8) {
> + stbi__rewind( s );
> + return 0;
> + }
> + } while (chained);
> +
> + *comp = (act_comp & 0x10 ? 4 : 3);
> +
> + return 1;
> +}
> +#endif
> +
> +// *************************************************************************************************
> +// Portable Gray Map and Portable Pixel Map loader
> +// by Ken Miller
> +//
> +// PGM: http://netpbm.sourceforge.net/doc/pgm.html
> +// PPM: http://netpbm.sourceforge.net/doc/ppm.html
> +//
> +// Known limitations:
> +// Does not support comments in the header section
> +// Does not support ASCII image data (formats P2 and P3)
> +// Does not support 16-bit-per-channel
> +
> +#ifndef STBI_NO_PNM
> +
> +static int stbi__pnm_test(stbi__context *s)
> +{
> + char p, t;
> + p = (char) stbi__get8(s);
> + t = (char) stbi__get8(s);
> + if (p != 'P' || (t != '5' && t != '6')) {
> + stbi__rewind( s );
> + return 0;
> + }
> + return 1;
> +}
> +
> +static void *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
> +{
> + stbi_uc *out;
> + STBI_NOTUSED(ri);
> +
> + if (!stbi__pnm_info(s, (int *)&s->img_x, (int *)&s->img_y, (int *)&s->img_n))
> + return 0;
> +
> + if (s->img_y > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> + if (s->img_x > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
> +
> + *x = s->img_x;
> + *y = s->img_y;
> + if (comp) *comp = s->img_n;
> +
> + if (!stbi__mad3sizes_valid(s->img_n, s->img_x, s->img_y, 0))
> + return stbi__errpuc("too large", "PNM too large");
> +
> + out = (stbi_uc *) stbi__malloc_mad3(s->img_n, s->img_x, s->img_y, 0);
> + if (!out) return stbi__errpuc("outofmem", "Out of memory");
> + stbi__getn(s, out, s->img_n * s->img_x * s->img_y);
> +
> + if (req_comp && req_comp != s->img_n) {
> + out = stbi__convert_format(out, s->img_n, req_comp, s->img_x, s->img_y);
> + if (out == NULL) return out; // stbi__convert_format frees input on failure
> + }
> + return out;
> +}
> +
> +static int stbi__pnm_isspace(char c)
> +{
> + return c == ' ' || c == '\t' || c == '\n' || c == '\v' || c == '\f' || c == '\r';
> +}
> +
> +static void stbi__pnm_skip_whitespace(stbi__context *s, char *c)
> +{
> + for (;;) {
> + while (!stbi__at_eof(s) && stbi__pnm_isspace(*c))
> + *c = (char) stbi__get8(s);
> +
> + if (stbi__at_eof(s) || *c != '#')
> + break;
> +
> + while (!stbi__at_eof(s) && *c != '\n' && *c != '\r' )
> + *c = (char) stbi__get8(s);
> + }
> +}
> +
> +static int stbi__pnm_isdigit(char c)
> +{
> + return c >= '0' && c <= '9';
> +}
> +
> +static int stbi__pnm_getinteger(stbi__context *s, char *c)
> +{
> + int value = 0;
> +
> + while (!stbi__at_eof(s) && stbi__pnm_isdigit(*c)) {
> + value = value*10 + (*c - '0');
> + *c = (char) stbi__get8(s);
> + }
> +
> + return value;
> +}
> +
> +static int stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp)
> +{
> + int maxv, dummy;
> + char c, p, t;
> +
> + if (!x) x = &dummy;
> + if (!y) y = &dummy;
> + if (!comp) comp = &dummy;
> +
> + stbi__rewind(s);
> +
> + // Get identifier
> + p = (char) stbi__get8(s);
> + t = (char) stbi__get8(s);
> + if (p != 'P' || (t != '5' && t != '6')) {
> + stbi__rewind(s);
> + return 0;
> + }
> +
> + *comp = (t == '6') ? 3 : 1; // '5' is 1-component .pgm; '6' is 3-component .ppm
> +
> + c = (char) stbi__get8(s);
> + stbi__pnm_skip_whitespace(s, &c);
> +
> + *x = stbi__pnm_getinteger(s, &c); // read width
> + stbi__pnm_skip_whitespace(s, &c);
> +
> + *y = stbi__pnm_getinteger(s, &c); // read height
> + stbi__pnm_skip_whitespace(s, &c);
> +
> + maxv = stbi__pnm_getinteger(s, &c); // read max value
> +
> + if (maxv > 255)
> + return stbi__err("max value > 255", "PPM image not 8-bit");
> + else
> + return 1;
> +}
> +#endif
> +
> +static int stbi__info_main(stbi__context *s, int *x, int *y, int *comp)
> +{
> + #ifndef STBI_NO_JPEG
> + if (stbi__jpeg_info(s, x, y, comp)) return 1;
> + #endif
> +
> + #ifndef STBI_NO_PNG
> + if (stbi__png_info(s, x, y, comp)) return 1;
> + #endif
> +
> + #ifndef STBI_NO_GIF
> + if (stbi__gif_info(s, x, y, comp)) return 1;
> + #endif
> +
> + #ifndef STBI_NO_BMP
> + if (stbi__bmp_info(s, x, y, comp)) return 1;
> + #endif
> +
> + #ifndef STBI_NO_PSD
> + if (stbi__psd_info(s, x, y, comp)) return 1;
> + #endif
> +
> + #ifndef STBI_NO_PIC
> + if (stbi__pic_info(s, x, y, comp)) return 1;
> + #endif
> +
> + #ifndef STBI_NO_PNM
> + if (stbi__pnm_info(s, x, y, comp)) return 1;
> + #endif
> +
> + #ifndef STBI_NO_HDR
> + if (stbi__hdr_info(s, x, y, comp)) return 1;
> + #endif
> +
> + // test tga last because it's a crappy test!
> + #ifndef STBI_NO_TGA
> + if (stbi__tga_info(s, x, y, comp))
> + return 1;
> + #endif
> + return stbi__err("unknown image type", "Image not of any known type, or corrupt");
> +}
> +
> +static int stbi__is_16_main(stbi__context *s)
> +{
> + #ifndef STBI_NO_PNG
> + if (stbi__png_is16(s)) return 1;
> + #endif
> +
> + #ifndef STBI_NO_PSD
> + if (stbi__psd_is16(s)) return 1;
> + #endif
> +
> + return 0;
> +}
> +
> +#ifndef STBI_NO_STDIO
> +STBIDEF int stbi_info(char const *filename, int *x, int *y, int *comp)
> +{
> + FILE *f = stbi__fopen(filename, "rb");
> + int result;
> + if (!f) return stbi__err("can't fopen", "Unable to open file");
> + result = stbi_info_from_file(f, x, y, comp);
> + fclose(f);
> + return result;
> +}
> +
> +STBIDEF int stbi_info_from_file(FILE *f, int *x, int *y, int *comp)
> +{
> + int r;
> + stbi__context s;
> + long pos = ftell(f);
> + stbi__start_file(&s, f);
> + r = stbi__info_main(&s,x,y,comp);
> + fseek(f,pos,SEEK_SET);
> + return r;
> +}
> +
> +STBIDEF int stbi_is_16_bit(char const *filename)
> +{
> + FILE *f = stbi__fopen(filename, "rb");
> + int result;
> + if (!f) return stbi__err("can't fopen", "Unable to open file");
> + result = stbi_is_16_bit_from_file(f);
> + fclose(f);
> + return result;
> +}
> +
> +STBIDEF int stbi_is_16_bit_from_file(FILE *f)
> +{
> + int r;
> + stbi__context s;
> + long pos = ftell(f);
> + stbi__start_file(&s, f);
> + r = stbi__is_16_main(&s);
> + fseek(f,pos,SEEK_SET);
> + return r;
> +}
> +#endif // !STBI_NO_STDIO
> +
> +STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp)
> +{
> + stbi__context s;
> + stbi__start_mem(&s,buffer,len);
> + return stbi__info_main(&s,x,y,comp);
> +}
> +
> +STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *c, void *user, int *x, int *y, int *comp)
> +{
> + stbi__context s;
> + stbi__start_callbacks(&s, (stbi_io_callbacks *) c, user);
> + return stbi__info_main(&s,x,y,comp);
> +}
> +
> +STBIDEF int stbi_is_16_bit_from_memory(stbi_uc const *buffer, int len)
> +{
> + stbi__context s;
> + stbi__start_mem(&s,buffer,len);
> + return stbi__is_16_main(&s);
> +}
> +
> +STBIDEF int stbi_is_16_bit_from_callbacks(stbi_io_callbacks const *c, void *user)
> +{
> + stbi__context s;
> + stbi__start_callbacks(&s, (stbi_io_callbacks *) c, user);
> + return stbi__is_16_main(&s);
> +}
> +
> +#endif // STB_IMAGE_IMPLEMENTATION
> +
> +/*
> + revision history:
> + 2.20 (2019-02-07) support utf8 filenames in Windows; fix warnings and platform ifdefs
> + 2.19 (2018-02-11) fix warning
> + 2.18 (2018-01-30) fix warnings
> + 2.17 (2018-01-29) change sbti__shiftsigned to avoid clang -O2 bug
> + 1-bit BMP
> + *_is_16_bit api
> + avoid warnings
> + 2.16 (2017-07-23) all functions have 16-bit variants;
> + STBI_NO_STDIO works again;
> + compilation fixes;
> + fix rounding in unpremultiply;
> + optimize vertical flip;
> + disable raw_len validation;
> + documentation fixes
> + 2.15 (2017-03-18) fix png-1,2,4 bug; now all Imagenet JPGs decode;
> + warning fixes; disable run-time SSE detection on gcc;
> + uniform handling of optional "return" values;
> + thread-safe initialization of zlib tables
> + 2.14 (2017-03-03) remove deprecated STBI_JPEG_OLD; fixes for Imagenet JPGs
> + 2.13 (2016-11-29) add 16-bit API, only supported for PNG right now
> + 2.12 (2016-04-02) fix typo in 2.11 PSD fix that caused crashes
> + 2.11 (2016-04-02) allocate large structures on the stack
> + remove white matting for transparent PSD
> + fix reported channel count for PNG & BMP
> + re-enable SSE2 in non-gcc 64-bit
> + support RGB-formatted JPEG
> + read 16-bit PNGs (only as 8-bit)
> + 2.10 (2016-01-22) avoid warning introduced in 2.09 by STBI_REALLOC_SIZED
> + 2.09 (2016-01-16) allow comments in PNM files
> + 16-bit-per-pixel TGA (not bit-per-component)
> + info() for TGA could break due to .hdr handling
> + info() for BMP to shares code instead of sloppy parse
> + can use STBI_REALLOC_SIZED if allocator doesn't support realloc
> + code cleanup
> + 2.08 (2015-09-13) fix to 2.07 cleanup, reading RGB PSD as RGBA
> + 2.07 (2015-09-13) fix compiler warnings
> + partial animated GIF support
> + limited 16-bpc PSD support
> + #ifdef unused functions
> + bug with < 92 byte PIC,PNM,HDR,TGA
> + 2.06 (2015-04-19) fix bug where PSD returns wrong '*comp' value
> + 2.05 (2015-04-19) fix bug in progressive JPEG handling, fix warning
> + 2.04 (2015-04-15) try to re-enable SIMD on MinGW 64-bit
> + 2.03 (2015-04-12) extra corruption checking (mmozeiko)
> + stbi_set_flip_vertically_on_load (nguillemot)
> + fix NEON support; fix mingw support
> + 2.02 (2015-01-19) fix incorrect assert, fix warning
> + 2.01 (2015-01-17) fix various warnings; suppress SIMD on gcc 32-bit without -msse2
> + 2.00b (2014-12-25) fix STBI_MALLOC in progressive JPEG
> + 2.00 (2014-12-25) optimize JPG, including x86 SSE2 & NEON SIMD (ryg)
> + progressive JPEG (stb)
> + PGM/PPM support (Ken Miller)
> + STBI_MALLOC,STBI_REALLOC,STBI_FREE
> + GIF bugfix -- seemingly never worked
> + STBI_NO_*, STBI_ONLY_*
> + 1.48 (2014-12-14) fix incorrectly-named assert()
> + 1.47 (2014-12-14) 1/2/4-bit PNG support, both direct and paletted (Omar Cornut & stb)
> + optimize PNG (ryg)
> + fix bug in interlaced PNG with user-specified channel count (stb)
> + 1.46 (2014-08-26)
> + fix broken tRNS chunk (colorkey-style transparency) in non-paletted PNG
> + 1.45 (2014-08-16)
> + fix MSVC-ARM internal compiler error by wrapping malloc
> + 1.44 (2014-08-07)
> + various warning fixes from Ronny Chevalier
> + 1.43 (2014-07-15)
> + fix MSVC-only compiler problem in code changed in 1.42
> + 1.42 (2014-07-09)
> + don't define _CRT_SECURE_NO_WARNINGS (affects user code)
> + fixes to stbi__cleanup_jpeg path
> + added STBI_ASSERT to avoid requiring assert.h
> + 1.41 (2014-06-25)
> + fix search&replace from 1.36 that messed up comments/error messages
> + 1.40 (2014-06-22)
> + fix gcc struct-initialization warning
> + 1.39 (2014-06-15)
> + fix to TGA optimization when req_comp != number of components in TGA;
> + fix to GIF loading because BMP wasn't rewinding (whoops, no GIFs in my test suite)
> + add support for BMP version 5 (more ignored fields)
> + 1.38 (2014-06-06)
> + suppress MSVC warnings on integer casts truncating values
> + fix accidental rename of 'skip' field of I/O
> + 1.37 (2014-06-04)
> + remove duplicate typedef
> + 1.36 (2014-06-03)
> + convert to header file single-file library
> + if de-iphone isn't set, load iphone images color-swapped instead of returning NULL
> + 1.35 (2014-05-27)
> + various warnings
> + fix broken STBI_SIMD path
> + fix bug where stbi_load_from_file no longer left file pointer in correct place
> + fix broken non-easy path for 32-bit BMP (possibly never used)
> + TGA optimization by Arseny Kapoulkine
> + 1.34 (unknown)
> + use STBI_NOTUSED in stbi__resample_row_generic(), fix one more leak in tga failure case
> + 1.33 (2011-07-14)
> + make stbi_is_hdr work in STBI_NO_HDR (as specified), minor compiler-friendly improvements
> + 1.32 (2011-07-13)
> + support for "info" function for all supported filetypes (SpartanJ)
> + 1.31 (2011-06-20)
> + a few more leak fixes, bug in PNG handling (SpartanJ)
> + 1.30 (2011-06-11)
> + added ability to load files via callbacks to accomidate custom input streams (Ben Wenger)
> + removed deprecated format-specific test/load functions
> + removed support for installable file formats (stbi_loader) -- would have been broken for IO callbacks anyway
> + error cases in bmp and tga give messages and don't leak (Raymond Barbiero, grisha)
> + fix inefficiency in decoding 32-bit BMP (David Woo)
> + 1.29 (2010-08-16)
> + various warning fixes from Aurelien Pocheville
> + 1.28 (2010-08-01)
> + fix bug in GIF palette transparency (SpartanJ)
> + 1.27 (2010-08-01)
> + cast-to-stbi_uc to fix warnings
> + 1.26 (2010-07-24)
> + fix bug in file buffering for PNG reported by SpartanJ
> + 1.25 (2010-07-17)
> + refix trans_data warning (Won Chun)
> + 1.24 (2010-07-12)
> + perf improvements reading from files on platforms with lock-heavy fgetc()
> + minor perf improvements for jpeg
> + deprecated type-specific functions so we'll get feedback if they're needed
> + attempt to fix trans_data warning (Won Chun)
> + 1.23 fixed bug in iPhone support
> + 1.22 (2010-07-10)
> + removed image *writing* support
> + stbi_info support from Jetro Lauha
> + GIF support from Jean-Marc Lienher
> + iPhone PNG-extensions from James Brown
> + warning-fixes from Nicolas Schulz and Janez Zemva (i.stbi__err. Janez (U+017D)emva)
> + 1.21 fix use of 'stbi_uc' in header (reported by jon blow)
> + 1.20 added support for Softimage PIC, by Tom Seddon
> + 1.19 bug in interlaced PNG corruption check (found by ryg)
> + 1.18 (2008-08-02)
> + fix a threading bug (local mutable static)
> + 1.17 support interlaced PNG
> + 1.16 major bugfix - stbi__convert_format converted one too many pixels
> + 1.15 initialize some fields for thread safety
> + 1.14 fix threadsafe conversion bug
> + header-file-only version (#define STBI_HEADER_FILE_ONLY before including)
> + 1.13 threadsafe
> + 1.12 const qualifiers in the API
> + 1.11 Support installable IDCT, colorspace conversion routines
> + 1.10 Fixes for 64-bit (don't use "unsigned long")
> + optimized upsampling by Fabian "ryg" Giesen
> + 1.09 Fix format-conversion for PSD code (bad global variables!)
> + 1.08 Thatcher Ulrich's PSD code integrated by Nicolas Schulz
> + 1.07 attempt to fix C++ warning/errors again
> + 1.06 attempt to fix C++ warning/errors again
> + 1.05 fix TGA loading to return correct *comp and use good luminance calc
> + 1.04 default float alpha is 1, not 255; use 'void *' for stbi_image_free
> + 1.03 bugfixes to STBI_NO_STDIO, STBI_NO_HDR
> + 1.02 support for (subset of) HDR files, float interface for preferred access to them
> + 1.01 fix bug: possible bug in handling right-side up bmps... not sure
> + fix bug: the stbi__bmp_load() and stbi__tga_load() functions didn't work at all
> + 1.00 interface to zlib that skips zlib header
> + 0.99 correct handling of alpha in palette
> + 0.98 TGA loader by lonesock; dynamically add loaders (untested)
> + 0.97 jpeg errors on too large a file; also catch another malloc failure
> + 0.96 fix detection of invalid v value - particleman at mollyrocket forum
> + 0.95 during header scan, seek to markers in case of padding
> + 0.94 STBI_NO_STDIO to disable stdio usage; rename all #defines the same
> + 0.93 handle jpegtran output; verbose errors
> + 0.92 read 4,8,16,24,32-bit BMP files of several formats
> + 0.91 output 24-bit Windows 3.0 BMP files
> + 0.90 fix a few more warnings; bump version number to approach 1.0
> + 0.61 bugfixes due to Marc LeBlanc, Christopher Lloyd
> + 0.60 fix compiling as c++
> + 0.59 fix warnings: merge Dave Moore's -Wall fixes
> + 0.58 fix bug: zlib uncompressed mode len/nlen was wrong endian
> + 0.57 fix bug: jpg last huffman symbol before marker was >9 bits but less than 16 available
> + 0.56 fix bug: zlib uncompressed mode len vs. nlen
> + 0.55 fix bug: restart_interval not initialized to 0
> + 0.54 allow NULL for 'int *comp'
> + 0.53 fix bug in png 3->4; speedup png decoding
> + 0.52 png handles req_comp=3,4 directly; minor cleanup; jpeg comments
> + 0.51 obey req_comp requests, 1-component jpegs return as 1-component,
> + on 'test' only check type, not whether we support this variant
> + 0.50 (2006-11-19)
> + first released version
> +*/
> +
> +
> +/*
> +------------------------------------------------------------------------------
> +This software is available under 2 licenses -- choose whichever you prefer.
> +------------------------------------------------------------------------------
> +ALTERNATIVE A - MIT License
> +Copyright (c) 2017 Sean Barrett
> +Permission is hereby granted, free of charge, to any person obtaining a copy of
> +this software and associated documentation files (the "Software"), to deal in
> +the Software without restriction, including without limitation the rights to
> +use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
> +of the Software, and to permit persons to whom the Software is furnished to do
> +so, subject to the following conditions:
> +The above copyright notice and this permission notice shall be included in all
> +copies or substantial portions of the Software.
> +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
> +SOFTWARE.
> +------------------------------------------------------------------------------
> +ALTERNATIVE B - Public Domain (www.unlicense.org)
> +This is free and unencumbered software released into the public domain.
> +Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
> +software, either in source code form or as a compiled binary, for any purpose,
> +commercial or non-commercial, and by any means.
> +In jurisdictions that recognize copyright laws, the author or authors of this
> +software dedicate any and all copyright interest in the software to the public
> +domain. We make this dedication for the benefit of the public at large and to
> +the detriment of our heirs and successors. We intend this dedication to be an
> +overt act of relinquishment in perpetuity of all present and future rights to
> +this software under copyright law.
> +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> +AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
> +ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
> +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
> +------------------------------------------------------------------------------
> +*/
>
--
Pengutronix e.K. | |
Steuerwalder Str. 21 | http://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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