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You should be able to pass multiple -ss
and -to
flags. Should look something like this;
ffmpeg -i "E01 - Part One [x265].mkv" -ss 00:05:50 -to 00:11:00 -c copy 1.mkv -ss 00:58:00 -to 00:68:00 -c copy 2.mkv
ffmpeg -i 1.mkv -i 2.mkv -filter_complex "[0:0][0:1][1:0][1:1]concat=n=2:v=1:a=1[outv][outa]" -map "[outv]" -map "[outa]" output.mkv
I’ve confirmed that this works fine.
https://youtu.be/T_D3d1RWBrI?t=5