如何获得RGB颜色的名称？

Question

How do you find the color name of a pixel in Java? I have found the RGB values of the pixel, but have no idea of how to get the name "yellow" from the pixel.

Answer 1

I haven't come across a part of the Java API that lets you do that. It is a feature you would most likely need to implement on your own, especially since not all rgb color combinations will have names.

One place you could start is by creating a lookup table using the rgb color values and names given on a site such as the Wikipedia list of colors page .

However, since not every combination of rgb values will map to a defined color, you would need to come up with an algorithm to map a set of values to the closest color. This could be something along the lines of computing the mean squared error between the rgb value for the pixel, and the rgb values for each color name. You could then pick the color name with the lowest score.

Here is a gist with some code (note however, it may not compile) that illustrates how a ColorNameLookup class that computes the mean square error to find the closest matching color name could work: https://gist.github.com/nightlark/6482130

Answer 2

there are some standard colors in java and others can be generated using RGB or HSB constructors. there is no way of getting the color name as there may be many combinations of RGB values (256 x 256 x 256) . Only few combinations have name (standard colors like white, red, yellow, black etc.)

Answer 3

I am sure, you have got the basic problem with your question.

If you are trying to find out the color name of any possible combination of RGB values, this will require a exhaustive storage where you already have mapped all possible RGB values to a unique color name.

This means, your question cannot be answered with 100% correctness, until this map is with you. But yes you can definitely find the color name for the colors defined in java.awt.Color class.

So, you can also use reflection in java to find out the list of public static final Color properties defined in the java.awt.Color and for each value of RGB you have, you can compare it across all the declared Color in java.