Patent ID: 6342951
Filing Date: 2002-01-29
Classification: G06F,H04N

Abstract:
A method of digital image processing comprising:receiving digital image data including a plurality of input pixel values selected from an input color gamut, each of said input pixel values defined in terms of plural gray values wherein each gray value is scaled into the range of 0&lE;gray value &lE;1, respectively mapping each input pixel value to an output pixel value, said mapping including: (a) individually inverting said gray values for each input pixel value according to the equation: 1-gray value, (b) applying a gamma value (&ggr;) individually to each inverted gray value according to the equation: (inverted gray value)&ggr;, said gamma value being related to an amount by which a dynamic lightness range of the digital image data is to be compressed relative to an output color gamut of an image output device, and, (c) inverting each inverted gray value after application of said gamma function thereto according to the equation: 1-(inverted gray value)&ggr;so that said gray values defining said input pixel values are mapped to gamma-modified gray values defining said output pixel values, respectively.