Brethern --

Is there a way to pass an RGB value to a function/module/etc and get back a fairly simple color name?

All I am looking to do is determine if a color is red, black, green, yellow, blue, etc (not mauve, terracotta, or taupe) based on it's RGB value.

The RGB value is not something nice and round like 255,0,0 for red but 223,8,13 (which still looks really red). So I can't do a look up in rgb.txt because there isn't an entry for that color.

I have tried using GD's 
colorClosest

$image->colorClosest(red,green,blue) object method 
This returns the index of the color closest in the color table to the 
+red green and blue components specified. If no colors have yet been a
+llocated, then this call returns -1.

Example:

        $apricot = $myImage->colorClosest(255,200,180);

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and then turn that into an RGB colorset so I can do a look up of the color via:
rgb

$image->rgb(colorIndex) object method 
This returns a list containing the red, green and blue components of t
+he specified color index.

Example:

        @RGB = $myImage->rgb($peachy);

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But for the example I gave for red above, it returns the exact same RGB numbers.

Couldn't find any modules on CPAN that would do what I want or out on the Net.

I figure this is a kind of subjective request ("does this look blue to you?") and that I'll probably have to write a routine that has a range of numbers that "equal" blue or red or whatever but am hoping this has already been done.

Thanks,
Matt

In reply to RGB values and color name by mdog

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