Generic Code Design Algorithms for Reversible Variable-length Codes from the Huffman Code

Variable-length codes (VLCs) are generally employed to improve compression efficiency using data statistics. However, VLCs are weak to bit errors in noisy transmission environments such as wireless channel. Recently, reversible variable-length codes (RVLCs) have been introduced due to their capability of recovering information from corrupted compressed streams; hence, enhancing the robustness of VLCs to bit errors. However, existing RVLCs are complicated in their design and have some room for improvement in coding efficiency. In this paper, we propose generic code construction algorithms both for symmetrical RVLCs and for asymmetrical RVLCs from the optimal Huffman code table. The proposed algorithms have simpler construction processes and also demonstrate improved performances in terms of the average codeword length than existing RVLC algorithms.