METHOD FOR PROCESSING VIDEO PICTURES FOR FALSE CONTOURS AND DITHERING NOISE COMPENSATION

摘要

A method for processing a video image for compensating false contour and dithering noise is provided to optimize reduction of the false contour effect and the dithering noise by using a GCC(Gravity Center Coding) codeword set. A RGB(Red,Green,Blue) image is transmitted to a gamma block(1) that performs a quadratic function such as out=4095X(input/maximum)^gamma. The gamma is about 2.2 and the maximum indicates a highest possible input value. An output of the gamma block is provided to a gradient extraction block(2). The gradient extraction block extracts a gradient level and sends it to a coding select block(3). The coding select block selects a GCC coding set to be used. A rescaling LUT(Look Up Table)(4) and a coding LUT(6) are updated based on the selected GCC coding set. A dithering block(7) adds a dithering having a 4-bit over in order for rendering a video signal accurately.