png.h RGB-palette conversion help

[floobles]

Hi, I'm trying to obtain the number of colors and possibly the color
table of png files. However, most of my files are RGB (not palette)
mode. Does anyone know how to obtain those info?

I am using the png.h library. I have tried using the png_set_dither
function to convert the rgb mode to palette mode, but did not succeed.
(I would prefer to be able to directly get the info from RGB mode
though.)

Thanks, much appreciated.

 

[Thomas Matthews]

Hi, I'm trying to obtain the number of colors and possibly the color
table of png files. However, most of my files are RGB (not palette)
mode. Does anyone know how to obtain those info?

Have you tried searching the web for the formats of PNG files?
http://www.wotsit.org

I am using the png.h library. I have tried using the png_set_dither
function to convert the rgb mode to palette mode, but did not succeed.
(I would prefer to be able to directly get the info from RGB mode
though.)

Thanks, much appreciated.

Perhaps some people in a graphics group or a group about
your platform could be of better assistance. In this
newsgroup, we discuss issues with the
language, not applications of the language. The language
does not have facilities for graphics or file formats,
so we don't discuss those topics here.

Read the FAQ and Welcome.txt below.

--
Thomas Matthews

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