Modern Error Correcting Codes And Their Applications In Distributed Video Coding

Distributed Source Coding (DSC) is a new communication frame which has a simple encoder. It is especially useful in practices in which the encoder has low computation abilities, such as mobile camera phones, sensor network and so on. DSC has been received much interest from industrial and academic fields at present. Distributed Video Coding (DVC) is an application of DSC in video coding. It enables low-complexity encoding by shifting the bulk of the computation to the decoder. This thesis proposes a DVC scheme which realizes video compression by intra-frame encoding and inter-frame decoding.Two modern error correcting codes, Turbo and LDPC, are studied and introduced to DVC under binary symmetric channel (BSC) to improve the quality of the whole system. The main work and achievements are as follows:1. Propose a DVC scheme based on Turbo codes, and reconstruct puncturing pattern to get Rate Compatible Punctured Turbo codes (RCPT), such pattern makes the code rate match inter-frame redundancy better.2. Propose a DVC scheme based on LDPC codes, and realize Rate Compatible Punctured LDPC codes (RC-LDPC) to match inter-frame redundancy.3. Experiment results show that LDPC is more suitable for DVC frame than Turbo.Compared with H.263+, our proposed system's PSNR value is 2-8dB higher than intra-frame encoding but lower than the inter-frame model based on motion compensation. For video sequences with high motion, LDPC performs better in our DVC system and have about 0.8 dB improvement in PSNR compared with Turbo.