[Magick-bugs] convert -colorize

[Salvatore De Paolis]

Hi all,

I'm trying to use convert, ImageMagick 6.2.4, with the colorize option
but I notice it doesn't really work properly.

First thing I notice is: (from documentation)

-colorize value

colorize the image with the fill color.

Specify the amount of colorization as a percentage. You can apply separate
colorization values to the red, green, and blue channels of the image with a
colorization value list delimited with commas (e.g. 0,0,50).

IHMO it would be much more comfortable to use normal rgb syntax
rgb(0|255,0|255,0|255) though the actual percentage way works the inverse as it
should be.
Eg. -colorize 0,0,100 don't give you a blue colorize as it recall (blue at
100%) but a yellow image (combine red,green). So the properly value for blue is
-colorize 100,100,0. Not really how it should be.

Second problem... colorize doesn't actually work as the Gimp colorize.
If I have a white picture and I want to colorize to blue I can do that.
If the picture is different from white, colorize do not work cause seems to
care of the original colour of the picture.
What follow of this is:
if you try to do:

convert test.jpg -colorize 50,50,50 test.jpg <- with input == output
it fails if you repeat this command more than one time cause you get different
colorations.

The Gimp colorize doesn't care of the current image colour and I think that's
the way it should be.

Best Regards
S.