How to ignore a 16-bit pseudocolour colourmap

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anthony
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Post by anthony » 2006-02-09T17:31:01-07:00

The color map is what contains the pixel values.

If you want just the colormap indexes the image is using, say as a grey scale image, then you are out of luck.. IM does the rigt thing according to the image, and that is to look up the colors from the color map, not use the index to the color map.

You will need to find some other program to convert colormap index values, into a greyscale image of some type. OR use the lower level API of Magcik Core to do the job. Not a simple matter.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
http://www.imagemagick.org/Usage/

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anthony
Posts: 8867
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Location: Brisbane, Australia

Post by anthony » 2006-02-12T20:46:42-07:00

If you want top access the pixel data, there are lots better formats than png.
Look at txt: xpm: and ppm: The latter can be made into a non-binary format
by filtering it with "pnmnoraw".
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
http://www.imagemagick.org/Usage/

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