Oliff & Berridge, PLC
Image forming apparatus and image processor
 To prevent the density of a low density part when an output image varies from the low density part to a high density part in a vertical scanning direction from being lowered without expanding an image forming apparatus or an image output device and increasing the cost, an image processing section first extracts an edge picture element of the low density part which is in contact with the high density part when an image output based upon input image data Si varies from the low density part to the high density part in the vertical scanning direction or from the high density part to the low density part in the vertical scanning direction. Next, the image processing section reads the number a of picture elements to be corrected and pixel value corrected quantity b from a look-up table based upon the low density part pixel value L and the high density part pixel value L before and after the edge picture element, corrects the pixel value of the input image data Si and sends the corrected output image data So to an image output section. 
Fuji Xerox Co., Ltd.
H G
H04N G06K
inventional inventional
Kouichiro Nobuyuki Masahiro Masahiko
Shinohara Kato Takamatsu Kubo