Optimization processing for integrated circuit physical design automation system using optimally switched cost function computations

摘要

There is provided a signal processing apparatus for processing input three primary color signals, which is capable of providing natural color reproduction. Input color signals R to B are subjected to a matrix operation to obtain color difference signals (R-Y)0 and (B-Y)0. The color signals R to B are compressed by means of high luminance compression circuits 12R to 12B, respectively, and these output color signals R1, G1 and B1 are subjected to obtain a luminance signal Y1, color difference signals (R-Y)1 and (B-Y)1. The respective outputs obtained from the matrix operation are operated by means of look-up tables 43 to 45 and 52 to obtain color difference signals (R-Y)3 and (B- Y)3 for representing a color which has the same hue as a hue &thgr; 0 of color represented by color signals R to B and a saturation same with the saturation r1 of color represented by color signals R1, G1 and B1. Then, the luminance signal Y1, color difference signals (R-Y)3 and (B- Y)3 are subjected to an inverse matrix operation to obtain output color signals Rn, Gn and Bn. The color signals thus obtained have no change in a hue and the saturation smaller than that of conventional ones even if high luminance compression processing is executed. Accordingly, a high luminance portion can be prevented from being too deeply colored.