| 摘要 |
<p>PROBLEM TO BE SOLVED: To code and compress image data at a high compression rate with a simple arithmetic operation in the method for compressing color image data. SOLUTION: A median Y of color signals (B, G, R) of color image data is calculated, color signals are separated into a luminance component Y and chrominance components according to equation in the step S2 and the luminance component is used for lightness information. A numeric pattern most adapted to a concerned chrominance component is selected by using a hue coding template decided in advance based on the concerned chrominance component (S3) as hue information, and a ratio of the chrominance component with respect to the numeric pattern is used for saturation information (S4). Then the data are coded by using the lightness information, the hue information and the saturation information obtained as above.</p> |
