Abstract-In this paper, we propose a family of short block codes (SBCs) designed for guaranteed convergence in soft-bitassisted iterative joint source and channel decoding, which facilitate improved iterative soft-bit source decoding (SBSD) and channel decoding. Data-partitioned (DP) H.264 source-coded video is used to evaluate the performance of our system using SBCassisted SBSD, in conjunction with recursive systematic convolution (RSC) codes for transmission over correlated narrow-band Rayleigh fading channels. The effect of different SBC schemes having diverse minimum Hamming distances d H,min and code rates on the attainable system performance is demonstrated, when using iterative SBSD and channel decoding, while keeping the overall bit rate budget constant by appropriately partitioning the total available bit rate budget between the source and channel codecs to improve the overall bit error rate (BER) performance and to enhance the objective video quality expressed in terms of peak signal-to-noise ratio (PSNR).1 EXtrinsic Information Transfer (EXIT) charts were used to analyze the attainable system performance. Explicitly, our experimental results show that the proposed error protection scheme using rate-1/3 SBCs having d H,min = 6 outperforms the identical-rate SBCs having d H,min = 3 by about 2.25 dB at the PSNR degradation point of 1 dB. Additionally, an E b /N 0 gain of 9 dB was achieved, compared with the rate-5/6 SBC having d H,min = 2 and an identical overall code rate. Furthermore, an E b /N 0 gain of 25 dB is attained at the PSNR degradation point of 1 dB while using iterative soft-bit source and channel decoding with the aid of rate-1/3 SBCs relative to the identical-rate benchmarker. . However, only moderate residual redundancy is left in the sourcecoded bit stream when using advanced state-of-the-art coding techniques. Therefore, we propose to deliberately impose additional redundancy on the source-coded bit stream with the aid of the novel class of SBCs proposed. In our experimental setup, the H.264/AVC video codec [13] is used to encode the input video sequence and generate the source-coded bit stream. The H.264/AVC codec employs heterogeneous variable length coding and predictive coding techniques to achieve high compression efficiency, which makes the compressed bit stream susceptible to transmission errors [1]. A single bit error in the coded stream may corrupt the decoding of numerous future codewords. Moreover, due to predictive coding, the effects of channel errors may affect the neighboring video blocks due to error propagation. Therefore, the transmission of compressed video over wireless systems is a challenging task. Various errorresilient schemes have been proposed in [1] to alleviate these problems, but the price paid is potential reduction in the achievable compression efficiency and increase in computational complexity. An iterative joint source-channel decoding procedure inspired by the concept of serial concatenated codes was presented in [14]. A symbol-based soft-input a post...

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Abstract-In this contribution we propose a robust H.264 coded wireless video transmission scheme using iteratively decoded self-concatenated convolutional coding (SECCC). The proposed SECCC scheme is composed of constituent recursive systematic convolutional (RSC) codes and an interleaver is used to randomise the extrinsic information exchanged between the constituent RSC codes. Additionally, a puncturer is used to increase the achievable bandwidth efficiency. At the receiver selfiterative decoding is invoked between the hypothetical decoder components. The performance of the system was evaluated using the H.264/AVC source codec for interactive video telephony. Furthermore, EXIT charts were utilised in order to analyse the convergence behaviour of the SECCC scheme advocated. We demonstrate the efficiency of this approach by showing that the video quality is significantly improved, when using the binary SECCC scheme. More explicitly, the proposed system exhibits an E b /N0 gain of 6 dB at the PSNR degradation point of 2 dB in comparison to the identical-rate benchmarker carrying out RSC coding and puncturing, while communicating over correlated Rayleigh fading channels.

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