[FFmpeg-user] Timestamp for variable frame rate (VFR ) video

[Wolfgang Hugemann]

> If the input file has the correct timestamps, then the pts function is what
> you need - it is not a "frame counter". You can format the output like
> shown at https://video.stackexchange.com/a/21907/1871

This had been my original approach, see my first e-mail. But the time
displayed (blended in) then strictly corresponded to CFR, although the
vfrdet filter (and the observation of the video itself) proofed differently.

(Same thing with ffprobe and best_effort_timestamp_time.)

Perhaps I shoulf first generate a VBR test video with known framerates ...

How could I possibly concatenate two videos with different framerate
into one with VFR? I tried

ffmpeg -y -vsync 2 -i "concat:25.avi|50.avi" test.mp4

with different values for vsync, but it seems that the first input video
settles the (constant) framerate of the output, i.e. 25 fps in the above
example.

Any ideas?

Wolfgang Hugemann