From: Ludvig Larsson <ludvig AT club-internet DOT fr>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Help: Converting 24bit bitmap to seperate R,G,B files using Allegro?
Date: Wed, 24 Feb 1999 02:30:25 +0100
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

As you are dealing with 24-bit color, there are no need
for a palette, 8-red bits, 8-green bits and 8 blue
gives about 16million colors.

I don't know if Allegro has any facilities to split up
24-bit colors in 8-bits, but from a normal .bmp the colors
are already split up(if it is saved in truecolormode, 24-bit).
AFAIK First 54 bytes are a header(info about size etc like byte [18]
+byte[19]*256 equals the width and the two following the height)
and then, the rest are one byte red-info one byte green, one byte
blue, one byte red info(for the second pixel then)etc.

If you want to split up a 8-bit bitmap, I think you
have to check up the corresponding colors in the palette and
therefrom gather the information about red-green-blue.

Or, maybe Allegro Do comes with a facility for this:)

HTH

Ludvig Larsson