Legacy ImageMagick Discussions Archive

How do I colorize an image (in the meaning of PSP or PS)?

I mean so it would only have one color in different tones.

Please see this post and add the extra details: viewtopic.php?f=1&t=9620

Ok... got an image:



Colorize process:

1. Turning it into a greyscale:



2. Colorizing it (for example to green):



3. Output:

FlashT wrote: ↑2018-01-17T15:08:01-07:003. Output:

From a Windows CMD prompt you can get very nearly that result with a command like this...
With ImageMagick you would use "-tint" to preserve the blacks and whites while adding color to the mid tones. The operator "-colorize" would add a certain percentage of the fill color over the entire image. Try the same command above with "-colorize 50" instead of "-tint 100" to see the difference in results.

On Debian, but will be the same...

Sorry, I didn't use imagemagick much before... and can't test it now... is "green" a named color? Can I use HTML color instead or something similar?

You can use:

Name Cyan

HEX #00ffff
You may need use ' around the colour '#00ffff'

RGB rgb\(0,255,255\)

RGBA rgba\(0,255,255,1\)

HSL hsl\(180,100,50\)

HSLA hsla\(180,100,50,1.0\)

CMYK cmyk\(100,0,0,0\)

CMYKA cmyka\(100,0,0,0,100\)

FlashT wrote: ↑2018-01-17T15:27:19-07:00Sorry, I didn't use imagemagick much before... and can't test it now... is "green" a named color? Can I use HTML color instead or something similar?

Yes, "green" is recognized by IM as a color name, and is equal to "rgb( 0, 128, 0)" or "#008000". See THIS PAGE for a list of colors and an explanation of all the ways you can specify colors in IM. Any of these methods should work here.

Thank you!

In the OPs screen snap, the hue=75 and saturation=128, do not make a green color. This would be the equivalent of GeeMack's command using HSV values.
You can see that from
# ImageMagick pixel enumeration: 1,1,65535,hsv
0,0: (21845,65535,32896) #55FF80 hsv(120,100%,50%)

Converting % to the range 0 to 255 gives: hsv(120,255,127.5)

What tool was used by the OP in that screen snap to do the colorizing? What is the range of Hue and Saturation values in that tool?

I've used (and still using) Paint Shop Pro 9 made in 2004 (the best graphics app ever made in my opinion, made by Jasc... when Corel bought it, they've ruined it totally). Hue and Saturation range is 0-255.

For hue of 75 that would be 360*75/255=106, which is not green (120). The value of 106 might still be a shade of green. But your saturation seems way off.

See:



Are you sure about the range of saturation in your tool? Might range from -128 to 128 or the like, so that 128 is max saturation?

Those numbers you show just do not make sense

I am totally sure, checked it to answer your question... both values are 0-255...




BTW... 0 is red as well as 255. You can see a color on bottom of value.

BTW... 0 is red as well as 255. You can see a color on bottom of value.

Yes, that makes sense if the range is 0 to 255. In normal hue the range is 0 to 360 with 0 and 360 being the same.

But that means your green color is slightly off as 75->106, but true green is 120. In Imagemagick green not rgb(0,255,0), but is rgb( 0, 128, 0). So a darker green at half the green channel. So its hue should still be 120.
# ImageMagick pixel enumeration: 1,1,65535,hsb
0,0: (21845,65535,32896) #55FF80 hsb(120,100%,50%)

Thus it would be Hue=120 (range 0 to 360) or 120*255/360=85 (not 75), Saturation 100% or 255 and Brightness 50% or 127.5

Your Hue=75:

Hue=85 (true green)

For additional information on specifying colors...
http://www.imagemagick.org/Usage/color_basics/#colors

And for the myriad methods and techniques available in re-coloring images...
http://www.imagemagick.org/Usage/color_mods/

For tinting...
http://www.imagemagick.org/Usage/color_mods/#tinting