CAM-based VLSI architecture for Huffman coding with real-time optimization of the code word table [image coding example]

• Main Authors: Kumaki, T., Kuroda, Y., Koide, T., Mattausch, H.J., Noda, H., Dosaka, K., Arimoto, K., Saito, K.
• Format: Conference Proceeding
• Language: English
• Subjects: CADCAM; Clocks; Computer aided manufacturing; Data compression; Encoding; Hardware; Huffman coding; Image coding; Image reconstruction; Very large scale integration
• ISSN: 0271-4302; 2158-1525
• DOI: 10.1109/ISCAS.2005.1465807

Huffman coding is probably the best known and most widely used data compression technique. Nevertheless, the task of further decreased compression ratio through Huffman code up-dating in real-time is still a largely unsolved problem. In this paper, a novel architecture for CAM (content addressable memory)-based Huffman coding with real-time optimization of the code word table, called CHRC, is proposed. A CAM is exploited to implement fast Huffman encoding, and simultaneously the code word table is reconstructed and up-dated in realtime. The effectiveness of the proposed architecture is verified by structure, encoding flow and simulation results. The example of a JPEG application shows that our proposed CHRC method is able to achieve up to 40% smaller encoded picture sizes, and 6 times smaller clock cycle number for the encoding hardware than conventional Huffman coding methods.