| 摘要 |
Color images are processed in a digital electronic device as data in the YCBCR (YUV) (luminance, chrominance-blue, chrominance-red) color space. However, output devices usually require the color data to be converted to RGB (red, green, blue) data and may have a color resolution less than the color resolution of the original image. The present invention provides a method of constructing a perceptually optimized color palette useful in converting higher resolution images of YCBCR data to lower resolution images of RGB data. To construct the palette the RGB color gamut is defined in the YCBCR color space. The YCBCR color space is divided into a grid of colors equally spaced along the CB and CR axes and perceptually equally spaced along the luminance, Y, axis. Colors in the grid are moved to the boundary of the RGB color gamut in each luminance plane to ensure maximally saturated colors. Substitutions for colors in the palette can also be made if incremental adjustment of coordinates of colors not on the boundary of the gamut of output colors reduces the variation of the palette colors.
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