Imagemagick Issue - transparency thats turning blue!

Questions and postings pertaining to the development of ImageMagick, feature enhancements, and ImageMagick internals. ImageMagick source code and algorithms are discussed here. Usage questions which are too arcane for the normal user list should also be posted here.
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magick
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Post by magick » 2006-06-21T15:56:03-07:00

The reason it happens is that GIF only supports one transparent color whereas many images have a variety of transparent values ranging from 0 to 255. Since transparency is binary we choose values from 0 to 127 as transparent and values from 128 to 255 as opaque. A future version of ImageMagick will permit you to specify a specific color as transparent instead of it deciding based on the alpha channel.

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Post by magick » 2006-06-21T18:26:58-07:00

See http://www.cit.gu.edu.au/~anthony/graphics/imagick6 for a discussion on how to make transparency work properly with GIF images and why GIF is a bad choice for transparent images and how PNG is the preferred choice.

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Post by magick » 2006-06-21T18:40:12-07:00

Perhaps there is a bug in the PSD image reader. Post a URL to your original PSD image so we can download it and reproduce the problem.

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Post by magick » 2006-06-21T19:13:04-07:00

Until we get a patch, try this:
  • convert '50cent1.psd[1]' 50cent1.png

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