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Graphics > Select numbers of 16color palettes

#22468 - ProblemBaby - Tue Jun 22, 2004 8:28 am

Hi

I wonder if anyone know a program/GBA tool or anything that
can convert an image to use 16 color palettes.
Here comes the tricky part: I want to be able to tell the tool how many palettes it should use if it overflows!

in Photoshop I can set how many colors a whole image should have
but the tiles can still have more than 16 colors in it and it doesnt
takes care of the transparent color in each 16-color bank.
But maybe i can trick with it cause it is quite much Index color functions in
photoshop!

Help would be great!

#22471 - sgeos - Tue Jun 22, 2004 11:19 am

I use the gimp. Make sure to put your transparent pixel in the upper lefthand corner. Then convert from RGB to Indexed.

Your transparent pixel will probably not be index 0 at this point. Convert back to RGB then back to Indexed and everrything should be good. This only works to convert full color images to 15 + transparency color images. Results are not alway good. (Render plasma and try converting it.)

-Brendan

#22478 - ProblemBaby - Tue Jun 22, 2004 1:33 pm

Yes I know but the problem is that I want to use more then one 16 color palette for my image.
Its hard to select myself which tiles that should use which one.

#22479 - sajiimori - Tue Jun 22, 2004 5:02 pm

There's a program called Quither that's been flying around here for a while. If you'd be interested, this sort of program can take a truecolor image, break it into tiles, and pick a set of 16 palettes that will retain as much accuracy as possible (according to the algorithm).

#22480 - cosmic4z - Tue Jun 22, 2004 5:15 pm

You can also do this in Pro Motion ... but the results are not what I would call good.

From a programmers perspective ... the main problem is calculating an optimal palette from a 24 bit colour image (and after that it's just a case of remapping colours to closest match).

Does anyone know of any online resources for computing an optimal palette !?
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#22488 - ProblemBaby - Tue Jun 22, 2004 11:04 pm

sajiimori:
Is it possible to get output in same format (Bitmap) with fixed palettes
with Quither.
And where can I find it?

#22492 - sajiimori - Wed Jun 23, 2004 1:31 am

I don't know its exact capabilities, but there's a link from the Announcements section, in one of the threads about color quantizers.

#22526 - Miked0801 - Wed Jun 23, 2004 5:55 pm

Yes. Go grab it and give it a run. It a pretty neat tool. You'll get 256 color bmps for output with the palettes aligned as needed.