Subblock-Based BPE Scheme to Conquer Mismatch in Memory Access Pattern

A novel subblock-based scheme for bit plane encoder (BPE) of EBCOT in JPEG2000 is presented to conquer the mismatch in access pattern to code block memory. A codeblock is partitioned into 4 times 4 subblocks and encoded subblock by subblock; each subblock is encoded as the traditional scheme. The new scheme is compatible to existing accelerating technologies, such as sample-parallel, pass-parallel, bit-plane-parallel. Moreover the parallelism between subblocks can be exploited. A subblock-parallel and sample-parallel BPE architecture is implemented in FPGA. The system throughput is improved from O(N²) to O(N), and memory requirement for status is decreased by > 30%. Experimental results show that our design outperforms related works considered by at least 1.3X and up to 26X.