| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method and device for compressing image data that can achieve improved image and at the same time excellent compression ratio. SOLUTION: This method for compressing image data has a cell reference compression process, and a line reference run length compression process. In the cell reference compression process, the image data consisting of n×m dots (n and m are multiples of y.) is divided into cells in y×y dots configuration before the cell reference compression process, the dot of the cell to be treated is compared with a corresponding one between the cells adjacent to the cell to be treated for dividing into a cell consisting of merely a heater and a cell consisting of the header and y×y dots data. In the line reference run length compression process, the cell consisting of the header and y×y dots is divided in line units, corresponding dots between a line to be treated and a reference line on the line 1 are compared, the header indicating the presence of the reference line is stored when they match, and the line without the reference line is subjected to run length compression.</p> |
