Legacy ImageMagick Discussions Archive

Conversion to an indexed PNG is erroneous if the number of colors in the input image is 1, 2, or 5 to 16, no matter if the input is indexed or not.

Example input

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~ $ convert in.png png8:out.png

Output

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~ $ convert -type palette in.png png8:out2.png

Output

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~ $ convert out2.png png8:out3.png

Output

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~ $ convert out3.png png8:out4.png

Output

Another example with a random image:

Input

, output

This seems to be the same issue as for croco.png in this thread, but I opened a new thread because there was already confusion about 2 issues in 1 thread.

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~ $ convert -version
Version: ImageMagick 6.4.3 2008-08-20 Q16 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2008 ImageMagick Studio LLC

We have a fix for the problem you reported in the Subversion trunk. It will also be available in the next point release.

I applied the patch from http://trac.imagemagick.org/changeset/11997 to 6.4.3-0 and it works for me now. Thanks for the quick fix!

BTW, this also seems to have fixed the bug with duplicate palette entries.

Legacy ImageMagick Discussions Archive

Error in indexed PNG output if number of colors <= 16

Error in indexed PNG output if number of colors <= 16

Re: Error in indexed PNG output if number of colors <= 16

Re: Error in indexed PNG output if number of colors <= 16