[FFmpeg-user] concat Missing part2.mov

[Dan Norton]

On Sat, 24 Mar 2018 18:43:35 -0800
Lou Logan <lou at lrcd.com> wrote:

> On Sat, Mar 24, 2018, at 3:10 PM, Dan Norton wrote:
> > I have two .mov files which were made on Debian 9 by running the
> > following:
> > 
> > $ ffmpeg -y -i "Norton 8mm Reel 04.mov" -ss 00:00:00 -to 00:20:00 -c
> > copy -bufsize 2048K part1.mov 
> > $ ffmpeg -y -ss 00:21:12 -i "Norton 8mm Reel 04.mov" -c copy
> > -bufsize 2048K part2.mov
> > 
> > Viewed individually part1 and part2 are OK. When I tried to
> > concatenate them, the output is missing part2. Here's what I did:
> > 
> > $ ffmpeg -i "concat:part1.mov|part2.mov" -c copy
> > out.mov   
> 
> The concat protocol is too simplistic for this format. It can only be
> used with inputs that support file level concatenation.
> 
> Use the concat demuxer instead.
> 
> https://ffmpeg.org/ffmpeg-formats.html#concat-1
> https://trac.ffmpeg.org/wiki/Concatenate#demuxer
> _______________________________________________

OK, I made "filelist" in the same directory as the videos, containing:
file 'part1.mov'
file 'part2.mov'

...and ran:
$ ffmpeg -y -f concat -i filelist -c copy out.mov

...which produced the desired result, despite two warning messages:

[concat @ 0x5615412aad80] Could not find codec parameters for stream 1
(Unknown: none): unknown codec Consider increasing the value for the
'analyzeduration' and 'probesize' options

[mov @ 0x5612acdcad80] Non-monotonous DTS in output stream 0:0;
previous: 14385600, current: 14385600; changing to 14385601. This may
result in incorrect timestamps in the output file.

Thanks, Lou.