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Re: images in php4

This is good enough. For more info, I'd suggest the svgalib mailing list. Sergio Masci might have some really helpful tips. Generally the palette is stored with the image and it is possible to have separate palettes for images. Also different images with the pallette missing will look strange if opened with a different palette. It is also possible to choose your own indexes in a simple text file (photo-cryptography anyone?) and use that to create png. No idea of GIF but guess that works the same way. "Definitive guide to PNG" is a great book on the subject.


PS: my program dnacgr has a snippet of code to generate png from a memory dump of the screen.

On Wed, Apr 11, 2001 at 11:40:20AM +0530, Kingsly John wrote:
> On Tue, 10 Apr 2001, Sudhakar Chandra wrote:
>  |What are indexed images?
> GIF's PNG etc are indexed images... they have a fixed number of colors
> which is stores in a color table(palette).. and then the image is rendered
> using the index number for the colors in the table/palette (so if you have
> a 256 color image each pixel is represented by a single number from 0-255
> (1byte)as opposed to RGB (3bytes)
> <disclaimer>
> This is a very rough explaination and may not be technically accurate
> </disclaimer>