| 摘要 |
PROBLEM TO BE SOLVED: To perform effective compression processing by deciding a compression processing method especially for every image data regarding a data compressing device for compressing printing data, display data, etc. SOLUTION: An image data, for example, read from a scanner device 8 is extracted for each specified number of pixel and classified, into the case that the number of gradation of all pixel data are the same, or the case that only the image data with the binarized number of gradation is included or the case that the image data is constituted of the image data with a random number of gradation and the compression processing which is optimum for each case is performed by a data compression program to be stored in a ROM 2. For example, when the number of the gradation for all the read image data are the same, the number of gradation is recorded, and when the image data with two kinds of the number of gradation are repeated, in which of the cases the data with two kinds of numbers of gradation and each pixel data are included is stored by, for example, the data '0', '1'. When the image data is constituted of the image data with the random number of gradation, an average value of the number of gradation is calculated, and the data of the average value is stored as the data of the number of gradation. |
