On Tue, 31 May 2022 13:15:02 +0200, Michael Koch <astroelectro...@t-online.de> wrote:
>> So reading this thread I get the feeling that there is a way to use the list >> of >> cut times in a *single ffmpeg command* to create the output mp4 file >> *without* >> creating the list file and essentially doing everything in this single ffmpeg >> command. > >I have a short example in chapter 2.57 of my book: >http://www.astro-electronic.de/FFmpeg_Book.pdf > >Michael > So I used the command that re-encodes the video from example 2.57 for an input file of 64 minutes where the cuts sum to 44m33s time ffmpeg -hide_banner \ -ss 25 -t 1100 -i input.mp4 \ -ss 1338 -t 265 -i input.u.mp4 \ -ss 1831 -t 573 -i input.u.mp4 \ -ss 2647 -t 735 -i input.u.mp4 \ -lavfi "concat=n=4:v=1:a=1" -an output.mp4 real 6m53.455s So this took almost 7 minutes to cut out the 4 sections and concatenate them onto the output file. I had to change :a=0 to :a=1 in order to get audio too. This slower concatenation (compared to using -c copy as in example 2.56) produces a much smoother video transition between cuts. No interruptions like I have in my existing concat function, which uses copy. But the downside is of course the long processing, using copy makes the process run for 3-6 seconds only... But it *is* a one-command ffmpeg concat of multiple sections in the same source file onto an output file including audio.... I also tried to concat using the 2.56 example but with two files recorded from the same stream but at different times. Did not work at all, the first part plays OK but the second half is muted and there are a lot of error output during the encoding, many-many lines like this: [mp4 @ 0x5622ce1a0200] Non-monotonous DTS in output stream 0:0; previous: 81976537, current: 81940035; changing to 81976538. This may result in incorrect timestamps in the output file. -- Bo Berglund Developer in Sweden _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".