ffmpeg: concat without temp files?

Question

Is it possible to concat without temp files using ffmpeg? eg;

# nice ffmpeg -v error -f concat \
  -ss "52.519" -copyts -to "53.153" -i in.mkv \
  -ss "53.186" -copyts -to "390.690" -i in.mkv \
  -ss "464.264" -copyts -to "2831.331" -i in.mkv \
  -c copy out.mkv < /dev/null
Invalid duration specification for ss: "52.519"

if so, what is ffmpeg version 4.2.4 complaining about? the "duration specification" is valid when using temp files followed by concat.

mkvtoolnix is able to do this btw.

Answer 1

If I understand the question correctly: yes! You can create a file that is a concatenation of different parts of the input video.

The script you're looking for is something like:

ffmpeg \
-i "$INPUT_FILE" \
-filter_complex \
"[0:v]trim=start=5:duration=10,setpts=PTS-STARTPTS[v0]; \
 [0:a]atrim=start=5:duration=10,asetpts=PTS-STARTPTS[a0]; \
 [0:v]trim=start=20:duration=10,setpts=PTS-STARTPTS[v1];
 [0:a]atrim=start=20:duration=10,asetpts=PTS-STARTPTS[a1]; \
 [v0][a0][v1][a1]concat=n=2:v=1:a=1[final]" \
-map "[final]" concat-video.mp4

You can read a little bit more about this on this blog post

(Disclaimer: I'm one of the co-founder of https://mediamachine.io)

Hope this helps!