WAVELET TRANSFORMATION ENCODING METHOD FOR DIGITAL IMAGE, AND DIGITAL IMAGE CODER

摘要

PROBLEM TO BE SOLVED: To process plural small areas by respective different transformation function in the transformation encoding of digital images. ;SOLUTION: An input image 11 is divided into image segments and a filter selected from a filter bank 13 for transformation is allocated to the respective segments. The filter bank 13 is composed of filters 13a 13b and 13n suited to the different kinds of image contents, and the filter is allocated to the respective image segments so as to generate minimum distortion at a given target bit rate. The respective filters generate the transformation coefficient of the segment by using sub band setting and a scale in common to the overall images. Then, the valid coefficients of the respective segments are combined, and a single combined wavelet image is formed. The image is similar to the single wavelet transformation of a complete image, however, the different filters are used and the different parts of coefficient images are created.;COPYRIGHT: (C)2000,JPO