[MPlayer-dev-eng] Re: ccache

[D Richard Felker III]

On Sun, Jan 05, 2003 at 11:28:13AM +0100, Attila Kinali wrote:
> On Sun, 5 Jan 2003 04:24:30 +0100
> Tobias Diedrich <td at sim.uni-hannover.de> wrote:
> 
> 
> > 6)
> > PAL vs. NTSC:
> > PAL has a slightly higher luma resolution, but a halfed chroma
> > resolution because of the Phase Alternating Line Color Encoding.
> > IIRC NTSC is information wise comparable to YUV422 while PAL carries
> > only as much information as an YUV411 picture...
> 
> 
> Can someone explain me how those numbers (420, 422, 411) are related
> to the picture format ? I never could find anything on the net about it.

I agree. The first relationship is obvious (4:2:? means 2 u/v samples
for every 4 y), but I have no idea how 4:2:2 is supposed to convey the
idea of one chroma line for each luma line, whereas 4:2:0 means one
chroma line for every two luma. Does anyone have any idea where this
confusing notation came from? (Perhaps MS? ;)

Rich