1. /******************************************************************************
2.  
3.  CALCULATES THE 'DISTANCE' BETWEEN TWO COLORS
4.  
5.  via: http://stackoverflow.com/questions/5066439/compare-pixel-colour-java
6.  
7.  ******************************************************************************/
8. float colorDist(color c1, color c2)
9. {
10.   float rmean =(red(c1) + red(c2)) / 2;
11.   float r = red(c1) - red(c2);
12.   float g = green(c1) - green(c2);
13.   float b = blue(c1) - blue(c2);
14.   return sqrt((int(((512+rmean)*r*r))>>8)+(4*g*g)+(int(((767-rmean)*b*b))>>8));
15. } // colorDist()

I hope it helps!

Rolf

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