| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an image compression apparatus, compressed image outputting apparatus, image compression method, computer program and recording medium, by which visibility of a character included in a compressed image can be improved. <P>SOLUTION: When compressing a source image by means of a compression processing section (image compressor) 3, in a color image processing apparatus 2, an edge of a black character and/or line drawing in the source image is detected, a foreground layer (first image) is produced by representing the detected edge as a binary image, and the foreground layer is reversibly compressed. Furthermore, a background layer (second image) is produced by reducing a density difference between the edge and another portion in the source image, and the background layer is irreversibly compressed. In an image obtained by expanding a compression file, a contour of the black character or line drawing is sharply represented. Furthermore, by reducing the density difference, noise caused by compression is reduced during irreversible compression. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
