Method and apparatus for generating binary image data of high resolution in relation to linear edges.

摘要

PURPOSE:To prevent the rattling from being produced in a corresponding high resolution edge part as much as possible even if there is a slight fluctuation in the straight line edge of an original picture by outputting high resolution binarization picture data constituting the smooth straight line edge to a picture element to be processed according to the gradient of the picture element to be processed. CONSTITUTION:In a high resolution circuit 3, the binarization picture data of higher resolution than a reading resolution is formed and processed by using the gradient in obtained multigradation picture data. The formed high gradation binarization picture data is compressed in run length by a compressor 4, and thereafter stored in a working memory 5 or a disk 6. A selector 15 receives a straight line edge detection signal X, selects the output data of the first high resolution circuit 12 when detecting the straight line edge and selects the output data of the second high resolution circuit 14 when X=1.