Thank you - great work ....

Vangelis forthnet northmedia1 at the.forthnet.gr
Fri Nov 7 12:48:06 PST 2014


On Fri Nov 7 14:12:27 GMT 2014, SquarePenguin wrote:

> After download it transcodes 
> (I think that's the right word) the flv to mp4

With respect SP, "transcodes" refers to change 
of video and/or audio codec (from one codec to 
another codec - this involves decoding the first 
codec and encode with a different codec, e.g. 
WMV+WMA -> Xvid+MP3). This is a time 
consuming and resource heavy process.
 What GiP does with video files is a simple 
change of container formats, from the Adobe 
proprietary FLash Video container to the more 
compatible with standalone players MP4 container; 
I think remux (short for re-multiplex) is the term 
that better describes this...

>> size=     116kB time=00:00:07.39 bitrate= 129.0kbits/s
>> size=     163kB time=00:00:10.34 bitrate= 128.7kbits/s
>
> Aren't those the transcoding rate indicators?

128kbps is the mean value of the bitrate of the 
flashaacstd audio mode; most probably, this is 
ffmpeg output from the remuxing process of the 
initial FLV container to the MP4 one (which, 
for audio streams, uses the Apple introduced 
.m4a file extension).
Unless the OP (CJB) has --aactomp3 in his 
"options" file, in which case it should be (as you say) 
ffmpeg output from the "transcoding" process 
of the AAC-LC audio stream (contained in the 
FLV file) to the end MP3 audio stream (GiP 
by default encodes to MP3 at 128kbps CBR).

Cheers,
Vangelis.



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