| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image processor capable of reducing a memory used for forming a histogram by forming a histogram of gradation values in a plurality of stages for the same frame data. <P>SOLUTION: The image processor has a histogram formation means for forming, every time when frame data are read, the histogram showing the frequency distribution of gradation values for the read frame data. The histogram formation means counts the frequency for every predetermined gradation number to form the histogram, and determines an effective gradation range from the formed histogram. The histogram formation means forms the histogram in a plurality of stages for the same frame data read a plurality of times. At this time, the histogram formation means forms the histogram only for the effective gradation range determined in the frame data read last. According to this, the memory for forming the histogram can be reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
