Pre-compression rate-distortion optimization method for JPEG 2000

摘要

A method of optimizing a compression of a still image in JPEG 2000 format, which includes the steps of: (a) dividing an image into a predetermined numbers of tiles each having a predetermined numbers of tile pixels; (b) decomposing each of the tiles into a predetermined number of subbands by Discrete Wavelet Transform (DWT); (c) partitioning each of the subbands into a predetermined number of code-blocks which are arranged into a plurality of bit-planes respectively; (d) minimizing a total rate with a given predetermined total distortion of image so as to pre-determine an optimal truncation point for each of the code-blocks; (e) truncating a predetermined part of the DWT coefficients for each of the code-blocks so as to reduce computational resource; and (f) encoding each of the code-blocks by embedded block-coding to form an embedded code-stream having a plurality of code passes.