PseudoColor overlay bits

[begal]

Hi all,

In overlay mode (8 bits pseudocolor + 24 bits truecolor), how come the number of colors in pseudocolor plane is 32 (5 bits).

Is it possible that the overlay is downgrading pseudocolor from 8 bits to 5?

Did I missed some configs in xorg.conf?

Thx

[AaronP]

Hi begal,

I assume you're talking about visuals that look like this (from xdpyinfo):

  visual:
    visual id:    0x70
    class:    PseudoColor
    depth:    8 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0x0, 0x0, 0x0
    significant bits in color specification:    5 bits

This means that the visual has 8 planes, for a total of 256 colormap entries. Each colormap entry has a depth of 15 bits (5 bits per channel) for a total of 32,768 colors per colormap entry. The reason it's 5 bits per channel and not 8 is because the overlay hardware only supports depth 15.

[begal]

My xdpyinfo is the same,

That means that we are stucked with 32 colors in pseudocolor when using overlay mode?

[begal]

Is there any cards doing 24 bits overlay ? (8 bits per channel)

[angel2]

Hi,
I'm also looking for a card that can support the full 8 bits in overlay mode. I've got a QUADRO FX 560 but it gives me only 5 significant bits per color. Which NVIDIA cards support the 8 bits/color in overlay mode?
thanks,