| 摘要 |
PROBLEM TO BE SOLVED: To prevent outline blur which is caused in a boundary between a low gradation area and a high gradation area due to pseudo multi-gradation processing. SOLUTION: This image processor is provided with: a first bit shift part 5 for performing bit shift to the pixel data of a result acquired by carrying out cumulative addition for noise shape processing; a second bit shift part 6 for simply carrying out bit shift to the input pixel data; an inter-pixel subtraction circuit 8 for calculating a gradation level difference between present pixel data and previous pixel data in a horizontal direction; a boundary decision circuit 9 for comparing a gradation level difference dh between adjacent pixels in a horizontal direction by the inter-pixel subtraction circuit 8 with a predetermined threshold th1, and for deciding the presence/no presence of a boundary between the low gradation area and high gradation area in the horizontal direction; and a selection means 7 for selecting bit shift pixel data by the first bit shift part 5 when it is decided that there is no boundary by the boundary decision circuit 9, and for selecting bit shift pixel data by the second bit shift part 6 when it is decided that there is any boundary as the result of decision. COPYRIGHT: (C)2008,JPO&INPIT
|
