[FFmpeg-user] Lossless cut from a h264 video with audio

Martin Underwood martin.underwood464 at gmail.com
Wed Oct 10 20:04:06 EEST 2018

>> Q: is there a way to cut a 10 second clip from a h264 video (downloaded 
>> from youtube) to later use it in web browsers with no quality loss?

> try this one...
> /usr/bin/env ffmpeg -y -ss 0:03:18  -i cook.mp4 -t 0:00:10 -c copy 
> cook-start.mp4 &> cook-start.txt

Does ffmpeg suffer from the same problem as AVIdemux that cuts must be made 
on a GOP boundary in order for the cut to be clean? Or does it recode a few 
full and differential frames so that the second clip of a cut always starts 
with a full frame followed by regenerated differential frames *wrt that full 
frame*, until the next full frame in the source video, like VideoReDo does?

Apologies for terms full and differential, but I can never remember which 
are I, B and P frames.

Is MPEG2 more prone to this problem than H264? 

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