[FFmpeg-devel] [PATCH] lavfi: add geq filter.

[Marton Balint]

On Thu, 1 Nov 2012, Stefano Sabatini wrote:

> On date Wednesday 2012-10-31 20:40:15 +0100, Clément Bœsch encoded:
>> TODO: bump minor
>> ---
>> Another portage from MPlayer filters. It seems to work, but I still have some
>> issues with ffplay when the filter is complex/heavy. Try for instance this one
>> (stolen from a random guy on #mplayer):
>>
>>     ffplay -f lavfi -i 'testsrc,geq=p(lt(X\,W/2)*X*(1+sin(N*PI/100))+not(lt(X\,W/2))*(W-X)*(1+sin(N*PI/100))\,lt(Y\,H/2)*Y*(1+sin(N*PI/100))+not(lt(Y\,H/2))*(H-Y)*(1+sin(N*PI/100)))'
>>
>> mplayer seems to deal relatively well with slow filters contrary to ffplay, but
>> I have no idea how to avoid the current frame drop (playing with the options
>> didn't help).
>
> -noframedrop may help
>

Yes, or use -sync video. In fact, only since a recent change ffplay forces 
realtime display of the video when no audio is present.

If you want realtime display AND useable output use this:

./ffplay -f lavfi -i 'testsrc' -vf 'geq=p(lt(X\,W/2)*X*(1+sin(N*PI/100))+not(lt(X\,W/2))*(W-X)*(1+sin(N*PI/100))\,lt(Y\,H/2)*Y*(1+sin(N*PI/100))+not(lt(Y\,H/2))*(H-Y)*(1+sin(N*PI/100)))'

It is better, because ffplay can detect that the filter processing is 
taking too much time and drop frames before passing them to the filter.

Regards,
Marton