| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an image processing unit that can execute gradation conversion processing and density conversion processing at the same time with less image quality deterioration without the need for a memory with a large capacity and an arithmetic means with a large-scale. SOLUTION: In the case of conducting double density gradation processing where input image data of an n-value (n>3) are converted into binary image data having double resolution in the main scanning direction, an error spread section 22 and a comparison section 23 process the input image data received from an input section 21 to convert the data into ternary image data. Then a pixel interpolation section 26 divides each pixel of the ternary image data into two, interpolates binary density processing to each division pixel and an output section 29 outputs the result. In a series of the processes above, each process is executed in parallel through the pipeline processing. Thus, since binary density is interpolated to the division pixels from pixels placed over a wider range by utilizing many more sets of information, high-speed processing and high image quality can be realized.</p> |
