Patent US 8,928,947

A method for contrast enhancement for digital images, including filtering an original image having original color values, to generate a filtered image, receiving parameters for a response curve, the response curve being a function of color value that is user-adjustable, deriving local multipliers by applying the response curve to the filtered image, multiplying the original color values by the local multipliers, thereby generating a contrast-enhanced image from the original image. A system and a computer-readable storage medium are also described.