| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a technology capable of enhancing processing efficiency in an image processing apparatus for carrying out tone reduction processing by using a plurality of processing methods. <P>SOLUTION: The image processing apparatus reduces the number of gradations of image data on the basis of which an image output apparatus outputs an image. The image processing apparatus is provided with a tone reduction unit for using the plurality of tone reduction processing methods whose processing contents differ from each other to reduce the number of gradations of each pixel of the image data to a prescribed number of gradations by each of a plurality of colors. The plurality of tone reduction methods are characterized by including: a first processing method that switches a color of a processing object every time the processing of a first pixel block including comparatively many pixels is finished, each pixel requiring comparatively many arithmetic processing volumes by each color; and a second processing method that switches a color of a processing object every time the processing of a second pixel block including comparatively a few pixels is finished, each pixel requiring comparatively a few arithmetic processing volumes for every color. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
