[Ffmpeg-devel] [PATCH] fix frame duration computation in find_stream_infos
Mon Apr 2 15:24:26 CEST 2007
Michael Niedermayer wrote:
>> We need something like "useful_frame_rate" that matches our intuitive
>> notions of the true speed of the file. :)
> no we dont, you want something you cant describe and cant implement
> and you reappear every few month and complain about it
It's true that I haven't kept up well with this list. My pattern of
reappearing is mainly due to seeing something that is particular
interest to me (frame rate) and commenting on it.
I commented on this case because it seems evident that others besides
myself are wrestling with the meaning of r_frame_rate, and that there
exists an intuitive expectation that something (whether it is
r_frame_rate or something else) give a fairly robust estimate of the
true frame rate of a video.
> fixed rate video has per definition clean timestamps if not its not fixed
> also average fps will not make any more sense than r_frame_rate for such
If a video file starts with one screwy frame, followed by 1000 precisely
and equally timed frames, then I would argue that it is "almost
everywhere" fixed rate. I also argue that it is useful to detect and
> so you complain about your own lazyness?
Yes. It is a confession, not a complaint. :)
>> but it is an existence proof that average
>> frame rate can be made useless.
> it IS useless beyond providing some statistics about the video ...
Agreed. The point was that there are cases where average frame rate is
useless. However, I am much more interested in the case where there are
a small number of screwy frames and a large number of well-timed frames.
More information about the ffmpeg-devel