| 摘要 |
PROBLEM TO BE SOLVED: To obtain a reduced image whose contour is sharp by stetting a reduction parameter so that the weighting value on a picture element in question is maximized and the weighting value of other picture elements than the picture element in question is a value inversely proportional to a distance of a picture element in question with respect to the picture element in question. SOLUTION: An input section 1 receives an original image and stores it to an original image buffer 2, and the input section 1 receives an image reduction rate and stores it to a reduction rate buffer 3. A reduction parameter decision means 41 stores a reduction parameter decided based on an image reduction rate of the buffer 3 to a reduction parameter buffer 42. That is, lateral and longitudinal picture elements of an integrated area and a weight of a filter to be multiplied with a gradation of each picture element are stored. A calculation value S of the integrated area is obtained by a specific equation based on the weight for the filter in the buffer 42. A gradation decision means 44 decides the gradation from the calculation value S based on a threshold level and the result is stored in a reduced image buffer 5. Vertical ruled lines in the image of the buffer 5 are retrieved, and the gradation of the picture element in a dark or light gray color is converted into a gradation value 3 indicating a white color and the result is outputted. |
