| 摘要 |
PROBLEM TO BE SOLVED: To provide a technology for enhancing a compression ratio of a color image and which is capable of sharply displaying the contour of characters or the like. SOLUTION: A hue cluster classification / integration section 15 decreases the number of hue values on the basis of a hue histogram, assigns the hue values whose number is decreased to each pixel of a color image and classifies pixels having the same hue value to one cluster. Further, the hue cluster classifying / integrating section 15 integrates clusters whose difference in hues is a prescribed value or smaller. Moreover, the hue cluster classifying / integrating section 15 traces the contour of clusters whose size is less than a reference value to discriminate the clusters including many change points as a character region. A coding section 17 discriminates the characteristics of the clusters, on the basis of the result of the discrimination of a region discrimination section 14 and a result of the discrimination of rules lines and the character region to code the cluster, in response to a coding method which in turn, in response to the characteristics of each cluster. COPYRIGHT: (C)2005,JPO&NCIPI |
