| 摘要 |
PROBLEM TO BE SOLVED: To reduce data saving from a main memory to a nonvolatile storage device.SOLUTION: In a file memory 16 allocated to the main memory, there is secured a necessary area which is an area having a size required to store compressed line image data 60 in the file memory 16 if one-page line image data 60 is compressed at an assumed compression rate Ra. Then, if even a part of band compression data 61 obtained from the line image data 60 by a compression circuit 10p cannot be stored in the necessary area, the band compression data 61 is saved into a mass storage device 10d while being stored on a partial basis into the necessary area. If it is possible to store, all band compressed data 61 are stored into the necessary area.SELECTED DRAWING: Figure 5 |
