hi!

here's my problem:

i have a 24bpp pic.

i want to dither that picture so that it looks good on a R5B5G5 display.
so i want the resulting image to be a bitmap (24bpp, wont be palettized) that only uses colors that have only 5bits per color, ie the 3 lowest bits to zero (cause the mobilephone display will cut them anyway).

BUT, i want the picture to be dithered anyway, using these (5bits=32shades per channel), or  2^15 colors, to make it look as there is more bits/channel , so more colors.

its simple in fact, how come i dont find some freeware to do it? if you know some commercial app that will do it (maybe PSP or Pshop) it's fine too.

many thanks!


Posted on 2007-04-11 12:39:49 by HeLLoWorld
photoshop can do it. just open picture and save-as in format you desire.

but IMHO you should just google for some free / trial "Image Converter", i saw lots of them around
Posted on 2007-04-11 12:53:16 by vid
its not as simple as saveing in another format.
its not 256 nor 32bpp...

BUT i have found how to do it!

photoshop annd the gimp can do it, this paper explains it:

http://tcpro.lasyk.net/files/dg_adapt_images_r2a.pdf

however you'll have to manually separate the channels, edit a grayscale uniform palette, dither the channels with this palette and recompose them, then save.

bye!
Posted on 2007-04-11 13:14:27 by HeLLoWorld