Audio and video gradually go out of sync

Vangelis forthnet northmedia1 at the.forthnet.gr
Wed Apr 20 08:33:13 PDT 2016


On Wed Apr 20 08:34:34 BST 2016, Nick Payne wrote:

> I used --modes=hlsbest for the download.
> This is the same option as for the other downloads
> which didn't suffer this loss of sync.

In GiP 2.94, that would've fetched hlshd1 (720p, 25FPS, ca. 2400kbps).
FFmpeg is used for the download (and lossless remux to MP4 container).

I typed:

get_iplayer --pid=b078dl2z --modes=hlshd1 --force --overwrite

and that got me an 807 MiB (48:25) tagged MP4 file - FFmpeg.exe v3.0 (32bit)
was used; File was tried in MPC-BE 1.4.6, MPC-HC 1.7.10, VLC 2.2.2 and 
PotPlayer 1.6.5:
in all players, AV was in sync up to the last second of duration.
So can't reproduce, it is definitely something at your end.

Please do as advised in my previous e-mail:

>> Delete problematic file and redownload manually,
>> at a time of day when your internet speed is the best

For flashhd type:

get_iplayer --pid=b078dl2z --modes=flashhd --force --overwrite

>> verify in the CLI that rtmpdump does not stop;

>> It's a long shot, but perhaps you could also update
>> your FFmpeg binary - GiP 2.94 came with FFmpeg 2.2.3,
>> we're now up to version 3.0.1; maybe significant
>> improvements were introduced in both AppleHLS
>> downloading and MP4 container remuxing...

To update FFmpeg, read towards the end of my recent list post:

http://lists.infradead.org/pipermail/get_iplayer/2016-April/008905.html

> I didn't notice any errors indicated in the console window.

It was an hls tvmode you fetched, so my initial remark applies:

>> (harder to spot those errors while
>> ffmpeg continuously writes output in the command
>> prompt window)

> Does GiP create a log file? I couldn't find one.

Not by default; you'd have to add --verbose (--debug) in
the CLI command and then redirect output to file; for flashhd:

get_iplayer --pid=b078dl2z --modes=flashhd --force --overwrite -v > 
"path-to\Log.txt" 2>&1

I personally do not have any other advice to suggest,
as it doesn't appear (at least to me) that GiP is at fault here...

Regards,
Vangelis. 




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