| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To flexibly change a compression distribution in a space frequency range by effectively utilizing conditions when image data is imaged. <P>SOLUTION: The method for compression coding comprises a trial step of digitizing and coding the image data after an orthogonal transformation by using a digitizing table obtained by multiplying a trial scale factor by a standard digitizing table, obtaining the compression coding amount of the image data, a parameter estimating step of estimating a scale factor for compressing the image data to a target code amount based on the compression code amount of the obtained image data, and a compression step of digitizing and coding the image data after the orthogonal transformation by using the digitizing table obtained by multiplying the estimated scale factor by the standard digitizing table. In this method, the trial step and the compression step prepare the standard digitizing table at each variation of imaging conditions, and selectively uses the standard digitizing table corresponding to the imaging conditions of the image data. <P>COPYRIGHT: (C)2003,JPO</p> |
