color problem EGA-VGA

color problem EGA-VGA

Post by Adelaida Delgad » Sat, 25 Nov 1995 04:00:00



When I save a graphic, done with a PC with a VGA, with 16 colors, and
then I load it into a PC with an EGA, there are important changes of
colors, for example red by blue. How could I resolve this problem?
 
 
 

color problem EGA-VGA

Post by David Bourgi » Wed, 29 Nov 1995 04:00:00



> When I save a graphic, done with a PC with a VGA, with 16 colors, and
> then I load it into a PC with an EGA, there are important changes of
> colors, for example red by blue. How could I resolve this problem?

When you're working on a picture, the most important of all notions
is the "definition". A definition of a picture contains:
- Size (WidthxHeight) in absolute or defined units
- Colors given with a color space (in your case it's RGB, except
if you consider the 4 bit-planes of the EGA/VGA cases) and the
colors used in the picture (in your case, the palette info must be
retrieved).

So your palette seems to not be the same in EGA and VGA applications.
You must store and load the palette. Never forget that EGA has
64 fixed different colors available with 16 index but VGA has 256
index using 262144 different fixed colors!

Hope it helps,

--
                                              David

David Bourgin - UFR IMA (French University - Grenoble)
I'm a netsurfer, and as such a citizen of the world!