[FFmpeg-user] Keeping A/V sync during telecine

[Carl Eugen Hoyos]

2017-12-30 20:24 GMT+01:00 Carl Zwanzig <cpz at tuunq.com>:
> On 12/30/2017 11:13 AM, Carl Eugen Hoyos wrote:
>>
>> 2017-12-29 22:03 GMT+01:00 Carl Zwanzig <cpz at tuunq.com>:
>>>
>>> cpz at video-proc-0:/mnt/videofiles % ffmpeg -r ntsc-film -i INPUT.vob
>
>> You cannot force an input frame-rate for variable frame-rate files,
>> or to say it differently, you can but it must lead to av-desync.
>
> Removing "-r ntsc-film" and setting the fps in the vf chain seems to produce
> proper sync in my limited test.

Just to make sure:
The fps filter drops frames from the 30fps segment of the input to
produce 24fps for the telecine filter (framerate interpolates).
Don't use fps (and telecine) if the input is already 30fps...

Carl Eugen