Memory efficient progressive rate-distortion algorithm for JPEG 2000

Abstract

A novel rate-distortion optimization algorithm for JPEG 2000 is proposed. In JPEG 2000 standard, the encoder generates a number of independent compressed bit streams. But it is the rate-control algorithm that generates truncation points for these bit streams in an optimal way in order to minimize the distortion according to a target bit rate. In this letter, we propose a computationally efficient rate-distortion optimization algorithm that generates the truncation points of the compressed bit streams during the encoding procedure to avoid unnecessary coding of the possible discarded bit streams for the given bit rate. This algorithm meets memory buffer requirement for the compressed bit streams quite strictly according to a given bit rate. Moreover, before the encoding process even starts, a required memory buffer size can be estimated. This algorithm can also help avoid unnecessary encoding for some parts of an image. Hence, it is memory efficient and supports progressive encoding also. In low bit rate application the proposed algorithm can greatly reduce the encoder complexity and buffer requirement.