/** * Turns an RGB value into grayscale. * * @param integer[] $originalPixel A hash with 'red', 'green', and 'blue' * values. * * @return integer[] A hash with 'red', 'green', and 'blue' values for the * corresponding gray color. */ public static function grayscalePixel($originalPixel) { $gray = Horde_Image::grayscaleValue($originalPixel['red'], $originalPixel['green'], $originalPixel['blue']); return array('red' => $gray, 'green' => $gray, 'blue' => $gray); }