[Lazarus] Extract the color data and alpha from a PNG image

[José Mejuto]

El 05/02/2013 15:36, silvioprog escribió:
> Hello friends,
>
> I'm trying to extract the color data and alpha from a PNG image. In PHP
> it is very easy to implement, but in FPC I don't know how to do it. I
> tried to do it via "chunk.data", "ZData" etc., but, without success.

The question is what information are you looking for ? The compressed 
PNG data, uncompressed, palette applied or not... I doubt that you need 
the raw uncompressed bitmap.

That PHP code is a toy and can handle only a subset of PNGs.

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