public static double getColorDistance(Color c1, Color c2) {
    double rmean = (c1.getRed() + c2.getRed()) / 2.0;
    int r = c1.getRed() - c2.getRed();
    int g = c1.getGreen() - c2.getGreen();
    int b = c1.getBlue() - c2.getBlue();
    double weightR = 2 + rmean / 256;
    double weightG = 4.0;
    double weightB = 2 + (255 - rmean) / 256;
    return Math.sqrt(weightR * r * r + weightG * g * g + weightB * b * b);
  }
public static double getColorDistance(Color c1, Color c2)