Abstract: With the broad application of the image coding algorithms to engineering, the researches on the memory-constrained image coding algorithms have been paid more and more attention to. In this paper, an embedded image coding algorithm based on zeroblock, called Embedded ZeroBlock coding with Optimized runcation(EZBOT), is presented. It operates the set-partition based on zeroblock, in which the independence between the zeroblocks ensures that the algorithm is effective under the memory-constrained condition. In order to improve the quality of the reconstructed image, we introduce an optimized truncation scheme to allocate the number of every sub-bitstream's bits. In this scheme, there is more than one truncation point available in every zeroblock, at which the value of the rate-distortion function can be computed. So, given the compression ratio, we can select the approximate optimized truncation point for every zeroblock according to the slope of the rate-distortion function at each truncation point. The experimental result shows that EZBOT is very effective under the memory-constrained condition.

Key words: zeroblock, set-partition, optimized truncation