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Tobias K
July 21st 05, 06:19 PM
Hello,

can anyone tell me how a 32 Bit Colormode works.

Is it:
8 Bit R, 8 Bit G, 8 Bit B, 8 Bit Brightness ?

Or how ?

Greetings

Tobias

Phil Weldon
July 21st 05, 08:53 PM
'Tobias K' wrote, in part:
| can anyone tell me how a 32 Bit Colormode works.

_____

Thirty-two bit color, true color is
8 bits for Red
8 bits for Green
8 bits for Blue.

Brightness (luminance is the correct term for a video signal) is the sum of
Red, Blue, and Green. Various levels of gray are equal values for Red,
Green, and Blue, from 0,0,0 for black to 255, 255, 255 for pure white.

This requires only 24 bits. The other 8 bits are either unused or serve
another purpose. The reason for 32 bits is that data is handled 32 bits at
a time, or some other power of two. Even if 8 bits are wasted, handling the
data 32 bits rather than 24 bits at a time is faster.

Phil Weldon


"Tobias K" > wrote in message
...
> Hello,
>
> can anyone tell me how a 32 Bit Colormode works.
>
> Is it:
> 8 Bit R, 8 Bit G, 8 Bit B, 8 Bit Brightness ?
>
> Or how ?
>
> Greetings
>
> Tobias
>

Robert Hancock
July 21st 05, 09:02 PM
Tobias K wrote:
> Hello,
>
> can anyone tell me how a 32 Bit Colormode works.
>
> Is it:
> 8 Bit R, 8 Bit G, 8 Bit B, 8 Bit Brightness ?
>
> Or how ?
>
> Greetings
>
> Tobias
>
>

There are 8 bits for R, G, B, and the other 8 bits are either unused or
used for something else (such as an alpha value for transparency). This
is more efficient than storing 24 bits per pixel since the video card's
memory bus is a multiple of 32 bits wide.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from
Home Page: http://www.roberthancock.com/

Granulated
July 22nd 05, 03:37 PM
On Thu, 21 Jul 2005 19:19:41 +0200 "Tobias K" > meeped :

>Hello,
>
>can anyone tell me how a 32 Bit Colormode works.
>
>Is it:
>8 Bit R, 8 Bit G, 8 Bit B, 8 Bit Brightness ?
>
>Or how ?
>
>Greetings
>
>Tobias
>

the extra 8 bits for alpha ?

(or is that just in graphics files ?)
--

Granulated
++++++++++
"Dang! You got shocks, pegs. Lucky!
You ever take it off any sweet jumps?"

Napoleon Dynamite

First of One
July 23rd 05, 02:30 AM
In 3D textures it's 8 R, 8 G, 8 B, 8 A (alpha transparency). I believe it's
also done this way in certain image file formats like TGA and PNG.

--
"War is the continuation of politics by other means.
It can therefore be said that politics is war without
bloodshed while war is politics with bloodshed."


"Tobias K" > wrote in message
...
> Hello,
>
> can anyone tell me how a 32 Bit Colormode works.
>
> Is it:
> 8 Bit R, 8 Bit G, 8 Bit B, 8 Bit Brightness ?
>
> Or how ?
>
> Greetings
>
> Tobias
>