[FFmpeg-devel] [RFC] consider all mpeg4 tb_unreliable()

[Måns Rullgård]

Reimar D?ffinger <Reimar.Doeffinger at stud.uni-karlsruhe.de> writes:

> On Fri, Mar 06, 2009 at 04:23:25PM +0100, elupus wrote:
>> I just ran into an avi file which contains a mpeg4 video stream with a
>> time_base of 23.9.. This have been muxed into a 25fps avi, and the audio
>> resampled to sync..
>> 
>> Now r_frame_rate for this file get's set to 23.9.. instead of the real
>> framerate (at playback based on timestamps), 25 fps.
>> 
>> Forcing the codec to be considered as tb_unreliable() will work for the
>> sample in question ( 25fpsVidConsidered24fps.avi in incomming ). 
>> 
>> But i'm not sure what other problems that might cause.
>> 
>> Any thoughs?
>
> That the real issue here is container vs. codec frame rate, and the
> container frame rate usually should be considered authoritative,
> at least for containers like AVI.

Except when the codec has the correct rate and the container is
telling lies.  I've seen both often enough with AVI that I wouldn't
pick either one blindly.

I don't play AVI files much these days though...

-- 
M?ns Rullg?rd
mans at mansr.com