The video fade filter has a start_frame option which starts the fade effect when the ordinal count of the processed frame reaches the start_frame value e.g.
ffmpeg -f lavfi -i testsrc2=d=5 -vf trim=2,fade=s=25:d=1 vfade-works-by-frame-count.mp4 In the command above, the video output fades in starting at pts_time 3.00 whereas the command, ffmpeg -f lavfi -i testsrc2=d=5 -vf trim=2,fade=st=1:d=1 vfade-fails-by-timestamp.mp4 fails because 'st' references timestamps and trim does not reset them. With the afade filter, the command ffmpeg -f lavfi -i sine=d=5 -af atrim=2,afade=ss=44100:d=1 afade-fails-by-sample-count.mp4 fails. Audio remains at native volume throughout. But the command ffmpeg -f lavfi -i sine=d=5 -af atrim=2,afade=ss=88200:d=1 afade-works-if-sample-count-is-pts.mp4 works. Audio fades in from pts_time 2.00 to 3.00. Which indicates that 'ss' refers to the original sample PTS rather than the ordinal count of processed audio samples. Is this intended? If yes, can one emulate the behaviour of the video fade filter. If no, should I file a bug report? All commands executed with N-85917 git-cc25a887c5 Thanks, Gyan _______________________________________________ ffmpeg-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
