Legacy ImageMagick Discussions Archive

I wolud fill - dinamically - another color at the place of a specific color... In other words I want use the "fill" tool of common grapfhic programs using imagemagick.


For example this image has two colors: black and white.. I would transform black to red.. to green.. to... another color



Thanks!! (sorry my english)

kali wrote:I wolud fill - dinamically - another color at the place of a specific color... In other words I want use the "fill" tool of common grapfhic programs using imagemagick.


For example this image has two colors: black and white.. I would transform black to red.. to green.. to... another color



Thanks!! (sorry my english)

The easiest way to change from black and white to any other colors is to use Anthony's new +level-colors, for example:

convert bw_image.jpg +level-colors red,blue rb_image.jpg

This will convert black to red and white to blue. You can assign any valid IM colors.

see

http://www.imagemagick.org/Usage/color/#level_plus
http://imagemagick.org/script/color.php

Use the -opaque option. Here's an example. http://www.imagemagick.org/Usage/color/#opaque

rmagick wrote:Use the -opaque option. Here's an example. http://www.imagemagick.org/Usage/color/#opaque

Thank your reply

I have solve using: convert mucca.jpg -fuzz 30% -fill red -opaque black balloon_red.gi

DO NOT USE -opaque This method only changes ONE exact or near-exact color (or NOT (+ form) that color) to another color without regard to color shades and anti-aliasing.

As given previously you can use the greyscale to color gradient replacement using +level-colors or turn white into transparency (negate to make black transparent) and set the other color using -alpha shape

given your original image as "cow.jpg"
This generates a red on white cow, without edge aliasing problems! See IM examples Level change by color

You will definatally NOT get such a 'clean' color change using -opaque