The video signal conversion device, image display device, the video signal conversion method

摘要

PROBLEM TO BE SOLVED: To provide an image signal conversion device where, upon converting a primary image signal having a color range that is larger than that of an image display part to a secondary image signal having a color range within that of the image display part, color continuity in the converted image signal is secured as much as possible, further, the signal conversion is carried out with low calculation load.;SOLUTION: In the case where intermediate signal values obtained by expressions (A1) and (A2) include values exceeding an output upper-limit value, the maximum intermediate signal value is converted to the output upper-limit value, and other intermediate signal values are compressed with a compression ratio smaller than a compression ratio used for the compression of the maximum intermediate signal value to the upper-limit value within an output extent, then, the secondary image signal is generated. If not in the case, the intermediate signal value is not converted, and used as the secondary image signal. In the expressions, Smin denotes an output lower-limit value, Xr to Xb denote RGB values of the primary image signal, k denotes constant, Lr to Lb denote RGB intermediate signal values.;COPYRIGHT: (C)2010,JPO&INPIT