code: private static final double[] getRGB(double cyan, double magenta, double yellow, double black) {
          double[] rgb = {0.0, 0.0, 0.0};
  
          rgb[0] = 1.0 - Math.min(1.0, cyan    * (1.0 - black) + black);
          rgb[1] = 1.0 - Math.min(1.0, magenta * (1.0 - black) + black);
          rgb[2] = 1.0 - Math.min(1.0, yellow  * (1.0 - black) + black);
  
          return rgb;
      }
docs: Convert CMYK (Cyan, Magenta, Yellow, Black) to RGB values.
  
  @param cyan
  @param magenta
  @param yellow
  @param black
  
  @return RGB values.