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K.I.L.E.R
25-Mar-2003, 11:48
http://www.rage3d.net/board/showthread.php?s=&threadid=33674893

quote:
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Ok tell you guys that want DV. Tell me what it is and I can give it to you. (bet you wont be able to tell me what it is).
Yeah I know color looks better...

Like I said before it is already there in our sliders already. If they are too dificult to use then I understand.

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From Catalyst Maker.

I told you about Omega using it on earlier drivers didn't I?
Well with a little bit of messing around you can get it similar to nVidia's. I already screwed around with the settings and made funny stuff occur.

Captain Chickenpants
25-Mar-2003, 12:10
DV (Digital Vibrance) is an increase of the colour saturation.

It cannot be done purely in drivers, their needs to be hw support for this. Gamma ramps are not sufficient.

As it requires transferring into YUV domain, and then calculate and increasing the saturation, followed by a conversion back into RGB.

Hue = tan^-1 (U/V)
Saturation = (UxU + VxV)^(1/2)

I think those are right ...


CC

Hyp-X
25-Mar-2003, 19:58
DV (Digital Vibrance) is an increase of the colour saturation.

It cannot be done purely in drivers, their needs to be hw support for this. Gamma ramps are not sufficient.

As it requires transferring into YUV domain, and then calculate and increasing the saturation, followed by a conversion back into RGB.

Hue = tan^-1 (U/V)
Saturation = (UxU + VxV)^(1/2)

I think those are right ...

CC

It can be done this way:

Y = 0.29900 * R + 0.58700 * G + 0.11400 * B

R' = Y + (R - Y) * sat
G' = Y + (G - Y) * sat
B' = Y + (B - Y) * sat

where sat=1 is the default, sat>1 increases saturation sat<1 decreases it.
when sat=0 the picture is fully desaturated.

Captain Chickenpants
26-Mar-2003, 08:36
It can be done this way:

Y = 0.29900 * R + 0.58700 * G + 0.11400 * B

R' = Y + (R - Y) * sat
G' = Y + (G - Y) * sat
B' = Y + (B - Y) * sat

where sat=1 is the default, sat>1 increases saturation sat<1 decreases it.
when sat=0 the picture is fully desaturated.


Nice, however it still cannot be handled with just a gammaramp, as R' is dependant on more than just R. Because G and B both affect Y.

I guess if someone really wanted to do it, they could use pixelshaders to do it. That would be a little messy and would impact performance.