An unrestrictedly parallel scheme for ultra-high-rate reprogrammable Huffman coding

This paper proposes a comprehensive method for overcoming the inherently serial nature of variable-length near-entropy coding to obtain unrestrictedly parallel realizations of Huffman compression. A codestream rearrangement technique together with a symbol-stream order-recovery procedure form a concurrent approach capable of exceeding all previously attainable code rate figures. Furthermore, the method is noteworthy for achieving 100% hardware utilization with no code rate overhead while maintaining data output in a traditional streamed format. To further this endeavor, bit-serial encoder and decoder designs that possess compelling speed and area advantages are developed for service as parallel processing elements. However, both are suitable in more general contexts as well. The decoder, in particular, is optimally fast. The encoder and decoder designs are programmable, thus suggesting the appropriateness of the composite approach for a general-purpose ultra-high-speed codec. The benefits for low-power and variable-rate applications are briefly discussed.