Image processing apparatus image forming apparatus and color image determination method thereof
OwnerYoshihiko Hirota, Katsuhisa Toyama +3inventors
InventorsYoshihiko Hirota, Katsuhisa Toyama, Shoji Imaizumi, Hideyuki Hashimoto, Kazuhiro Ishiguro
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Abstract
The inventive image processing apparatus takes steps of 1) dividing an image to be processed into numerals of blocks; 2) determining whether a block is a color block or not; 3) determining whether the image is a color image or not based on the rate of color blocks to the entire blocks. Thereby, valid color pixel rate can be obtained at blocks belonging to a color region even though an image is almost monochrome but partially colored. Accordingly, the inventive image processing apparatus can appropriately determine whether the image is a color image or not.
Claims7
An image processing apparatus including:
- a brightness data extracting section for extracting brightness data from image information of each pixel;
- means for determining a reference value based on extracted brightness data;
- a first determination means for determining whether or not a pixel included in an image is a color pixel by using the reference value;
- means for dividing the image into a predetermined number of a plurality of blocks;
- counting means for counting the number of color pixels for each block;
- and
- second determination means for determining whether or not the image is a color image based on the counting result by the counting means, wherein
- the second determination means determines whether or not an image is a color image even if the numbers of color pixels for blocks are not completely counted, and the counting means for counting the number of color pixels for each block stops counting operation after the second determination means completes color image determination.
Dependencies are inferred from the claim text.