I have an image sequence of 5,664 .tga images which are to be played at 24fps (so 236 seconds) and an audio ac3 file which I edited to be exactly 236 seconds (plus minus 0.01s) in length.
I used the following ffmpeg command to mix them into a .mpg file:
ffmpeg -i music.ac3 -i o%04d.tga -r 24 -sameq a.mpg
The audio played for the full 236 seconds; however the video finished at only 226 seconds, holding the final frame for the last 10s of audio.
Why is ffmpeg shortening my image sequence playback by 10s, and how can I get it to run for the full time?