[MPlayer-dev-eng] [PATCH] pc2tv/tv2pc conversion

[Michael Niedermayer]

Hi

On Thursday 08 July 2004 14:25, Nico Sabbi wrote:
> Michael Niedermayer wrote:
> >Hi
> >
> >On Thursday 08 July 2004 08:36, Nico Sabbi wrote:
> >>Il gio, 2004-07-08 alle 02:36, Michael Niedermayer ha scritto:
> >>>Hi
> >>>
> >>>On Wednesday 07 July 2004 19:53, Nico Sabbi wrote:
> >>>>This patch extends vf_yuvcsp.c to rescale luma and chroma when
> >>>>converting from tv->pc and viceversa.
> >>>>
> >>>>Now the filter accepts an optional parameter which can be "pc2tv",
> >>>>"tv2pc" or "clamp" (the default, old algorithm).
> >>>>
> >>>>It's implemented as a LUT for performance reasons.
> >>>>
> >>>>As far as I understand how CCIR601 works, this code seems to be
> >>>>correct, but I wish someone more familiar with colorspace conversions
> >>>>will give it a look.
> >>>
> >>>did u look at the tables? dont u think the pc2tv tables look strange?
> >>
> >>because of these sudden jumps from 0xd9 to the top?
> >>
> >>0xd7, 0xd8, 0xd8, 0xd9, 0xeb, 0xeb, 0xeb, 0xeb,
> >
> >yes
> >
> >[...]
>
> right, 1000l to me. What can you tell me about the dithering you were
> talking about in your previous mail?
> I never made anything of that kind.
its very easy, see vf_spp.c, grep for dither and RTFS the few related lines of 
code :)
the dithering implemented in vf_spp.c is a simple ordered dither, which is 
more then good enough for 24bpp output, for a low number of colors like 2 or 
16, FS dither and more complicated stuff will look much better though

[...]
-- 
Michael
level[i]= get_vlc(); i+=get_vlc();		(violates patent EP0266049)
median(mv[y-1][x], mv[y][x-1], mv[y+1][x+1]);	(violates patent #5,905,535)
buf[i]= qp - buf[i-1];				(violates patent #?)
for more examples, see http://mplayerhq.hu/~michael/patent.html
stop it, see http://petition.eurolinux.org & http://petition.ffii.org/eubsa/en