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jpg negated with -thumbnail option

Posted: 2011-01-27T22:03:12-07:00
by jsasitorn
When using the -thumbnail option in imagemagick 6.3.7 11/17/10, I got an image that became negated (negative b&w).
Image

Code: Select all

convert -thumbnail 400x350 -format jpg image.jpg  result.jpg
Produces:

Image

A normal resize performs as expected.

Code: Select all

convert -resize 400x350 -format jpg image.jpg  normal.jpg
Image

Is this a bug? Or am I not using this correctly?

Thanks,
James

Re: jpg negated with -thumbnail option

Posted: 2011-01-28T13:56:43-07:00
by jsasitorn
Never mind.. Figured it out. Its from the -strip option (-thumbnail does an implicit call to this). The -strip was removing the color profile, which is CYMK..

And I guess CYMK simply stripped of the profile is a negated RGB.