| 摘要 |
Two grey values for an original image, such as a facsimile image, are stored in a memory, 1 the image enhancement device 2' reads the grey values from the two greyscale image input memory 1 and enhances their pixels by enlarging them. The multiple grey-level converter 11 in the grey scale converter 10 converts the two grey values for the pixels into multiple grey values, and stores the multiple grey values in the multi- greyscale image input memory 4. The low-pass filter 6 then reads the grey values for the enhanced multi-greyscale image input memory 4, extracts low frequency elements to smooth the outline of the image and stores the low frequency elements in a memory 5. The determination means 12a of the two grey level converter 12 in the grey scale converter 10 reads multiple grey values from the memory 5. The grey values that are read are changed to two grey values by referring to the set value that is stored in advance in the set value area 12b and the two grey values are stored in the two greyscale image output memory 3. |
