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Transparent image loose color data?

Posted: 2009-07-03T00:47:20-07:00
by Pipen
Dear ppl,
I spent hours and hours trying to solve this, i use 6.4.5, but i also tried with 6.5.3-9

Code: Select all

convert characters_heading.png -resize 97% -alpha off -colors 256 -alpha on -depth 8 test.png
Why do the output image loose the orange color?

Image
Image


EDIT:
running 6.4.5 on ubuntu and 6.5.3-9 on debian

Re: Transparent image loose color data?

Posted: 2009-07-03T09:37:20-07:00
by fmw42
seems to have to do with -colors 256 making your image mostly black probably because the resize converted only a few colors into a lot of nearby colors and -colors 256 chose too many near black values.

this works, but I don't know if that is what you want

convert characters_heading.png -resize 97% -alpha off -alpha on -depth 8 test.png

and this works (kind of)

convert characters_heading.png -resize 97% -alpha off -alpha on -depth 8 -colors 256 test.png

Re: Transparent image loose color data?

Posted: 2009-07-05T23:34:59-07:00
by anthony
It also happens for -quantize transparent -colors 256 which should do the same thing and the -alpha off and on.

I have no idea why it is failing! I would report this as a bug of some kind!