Have you tried if it works on the command line with the regular ImageMagick convert command (as you've quoted)?  PerlMagick wouldn't be applying any other magick, essentially...

Not all operations make sense with all image types, such as "indexed" vs. "truecolor" (PNGs may be either).   Could you provide a sample image?

In reply to Re^3: perlmagick color change. by almut
in thread perlmagick color change. by Anonymous Monk

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