[FFmpeg-devel] [PATCH] libmpcodecs support

Reimar Döffinger Reimar.Doeffinger
Sat Jan 15 23:23:23 CET 2011

On Sat, Jan 15, 2011 at 11:10:36PM +0100, Michael Niedermayer wrote:
> On Sat, Jan 15, 2011 at 09:01:42PM +0100, Reimar D?ffinger wrote:
> > > i see nothing unpredictable on it
> > 
> > Let me explain: hue adjustments could be done for free for yuv<->rgb conversions.
> > This combined with above approach means that the results of the VFCTRL_SET_EQUALIZER will
> > mean that if you have
> > -vf swapuv
> > the behaviour off hue adjustment will be completely different for a RGB vs. a YUV
> > codec because for RGB you have the filters
> > scale(convert to yuv), swapuv, output
> > here hue adjustement would be done in scale, before swapuv.
> > With YUV input you'd only have
> > swapuv, output
> > and thus hue would be adjusted in output, i.e. after swapuv.
> yes but where is the difference between mplayer-libmpcodec and ffplay-libavfilter
> here?
> you said "for libavfilter that approach is likely too unpredictable though."

That libavfilter is supposed to be more general.
I realize that I forgot that it is possible to send a VFCTRL to a specific
filter if you know you want to change exactly that one.
Still, since libavfilter is a reimplementation thinking of a design that
allows avoiding this issue would make sense I'd say.
Anyway, that has nothing to do with the original issue, for which we
can just say at least inside MPlayer the hue etc. filters can be adjusted
dynamically (I haven't looked at your patch I admit).

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