[FFmpeg-soc] libavfilter: filter setpts

[Víctor Paesa]

Hi,

On 1/11/08, Vitor Sessak wrote:
> Hi
>
> Víctor Paesa wrote:
> > Hi,
> >
> > Here is attached a filter to manipulate the PTS.
> >
> > Could you please review it?
>
> I cannot spot anything wrong with it (apart a tiny nitpick), but I have
> to admit that there are some points in the filter API that I don't
> understand fully...

Neither do I ;-)

> BTW, when you do slow motion/fast motion with this filter, do you get
> the right FPS printed by ffmpeg.c? I don't think it will work without
> the fix I proposed in the "libavfilter: fps ignored in ffmpeg command
> line" thread (but thinking again about it, I can skip step 4 and just
> use the suggested_rate field only to print the fps in the UI)...

As you guessed, ffmpeg prints a wrong FPS. And the output.avi has
the right number of frames but a wrong FPS.

Maybe you can use this vf_setpts to torture the ffmpeg.c integration
code ;-)

> Now the nitpick:
>
> > Index: vf_setpts.c
> > ===================================================================
> > --- vf_setpts.c       (revision 0)
> > +++ vf_setpts.c       (revision 0)
> > @@ -0,0 +1,136 @@
> > +/*
> > + * Video pts modification filter
>
> Maybe write here "presentation timestamp" instead of "pts" in case a
> user tries to read the source to see what this filter does...

Commited with your suggestion.

Thanks for your review,
Víctor