[FFmpeg-user] Matroska segmented output changes video duration

[Carl Eugen Hoyos]

Am Mi., 29. Jan. 2020 um 22:47 Uhr schrieb andreymal via ffmpeg-user
<ffmpeg-user at ffmpeg.org>:
>
> Hello. I have a video grabbed from EasyCAP (UTV007). It has variable
> frame rate, so I use "-vsync passthrough" everywhere to keep it. You can
> download a segment of this video here:
> https://andreymal.org/files/ffmpeg/contra_test.mkv
>
> I need to split this video into several segments. I tried to use this
> command:
>
> ffmpeg -vsync passthrough -i contra_test.mkv \
>   -map 0 -c copy -f segment -segment_time 1 \
>   -segment_list test.ffcat -reset_timestamps 1 test-%02d.mkv
>
> To verify that everything is fine, I merge the video back:

Why do you think that this is possible in the general case?
(Apart from the fact that I suspect -vsync passthrough sees
significantly less testing than the default)

[...]

> I use ffmpeg 4.2.2 installed from Arch Linux repository.

Please test current FFmpeg before reporting issues here.

Carl Eugen