| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To compress image data according to a desired target code amount. <P>SOLUTION: An image data compression device executes quantizing processing and entropy coding processing for input image data which consists of luminance data and color difference data. The device divides a whole one screen by making a 2×2 block of a discrete cosine transform (DTC) coefficient regarding the luminance data out of a result of the DCT processing of the image data as one group unit, carries out quantizing processing and entropy coding processing of only each 1st block of the group over the whole one screen, obtains the code amount, executes processing to create a quantizing table for a 2nd block until a 4th block in order, creates the quantizing table which becomes a target luminance code amount by the result when the whole one screen is finally compressed, compresses the whole one screen of the luminance data, and outputs them together with the compressed data of the color difference data compressed before. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
