| 摘要 |
<p>PROBLEM TO BE SOLVED: To efficiently convert the multi-level picture data of a low resolution to the binary pictures of picture quality with no jaggy and with clear edges by resolution-converting first multi-level pictures to second multi-level pictures and converting the second multi-level pictures to the bindary pictures whose density is expressed by the combination of plural picture elements. SOLUTION: A window preparation part 102 prepares a window whose center is the picture element under consideration based on the picture information of the low resolution for several lines held in a line buffer 101. A resolution conversion part 103 converts one picture element under consideration to (n×m) picture elements by using a picture element value inside the window. In the conversion, when it is assumed that the picture element under consideration is information provided with the gradation number of A bits, it is converted to the information for (n×m) picture elements while the gradation number is kept as A bits. A density pattern part 104 prepares the binary information of the plural picture elements of vertically (N/n)-fold and horizontally (M/m) fold from one multilevel picture element after resolution conversion.</p> |
