This paper proposes a robust resilient transmission scheme for images that have been compressed using the Set Partitioning In Hierarchical Trees (SPIHT) algorithm. The scheme employs Unequal Error Protection (UEP), prioritised Automatic Repeat reQuest (ARQ) and twodimensional adaptive Wiener filtering. In order to apply UEP, the SPIHT coded bit-stream is partitioned into bit-classes of unequal importance. UEP is then applied at two levels. Firstly, Rate Compatible Punctured Convolutional (RCPC) codes are used to encode the bit-classes with different code-rates hence providing them with different levels of protection. Secondly, prioritized retransmissions are used such that the more important bit-classes are allocated a greater number of retransmissions than the less important ones. Equal gain combining is also performed to further improve the performance. The proposed UEP scheme provides an average gain of 3 dB in Peak Signal to Noise Ratio (PSNR) over a conventional Equal Error Protection (EEP) in the range 0dB≤Eb/No≤6dB with 16-QAM and an average gain of 3.5 dB in PSNR in the range 0dB≤Eb/No≤3dB with BPSK modulation. Moreover, de-noising with a two dimensional Wiener filter provides an additional gain of 0.76 to 0.90 dB.

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<p>H.264/AVC is currently the most widely adopted video coding standard due to its high compression capability and flexibility. However, compressed videos are highly vulnerable to channel errors which may result in severe quality degradation of a video. This paper presents a concealment aware Unequal Error Protection (UEP) scheme for H.264 video compression using Reed Solomon (RS) codes. The proposed UEP technique assigns a code rate to each Macroblock (MB) based on the type of concealment and a Concealment Dependent Index (CDI). Two interleaving techniques, namely Frame Level Interleaving (FLI) and Group Level Interleaving (GLI) have also been employed. Finally, prioritised concealment is applied in cases where error correction is beyond the capability of the RS decoder. Simulation results have demonstrated that the proposed framework provides an average gain of 2.96 dB over a scheme that used Equal Error Protection (EEP).</p>

Video compression standards such as H.264/AVC and H.265/HEVC are widely used in applications such as video conferencing, streaming and television broadcasting. These compression standards have been ubiquitously adopted due to their high compression performance as compared to previous standards. However, compressed video may suffer from severe degradation during transmission over unreliable channels due to packet losses which can result in low Quality of Service (QoS). In this paper, a new Space Time Flexible Macroblock Ordering (ST-FMO) scheme is proposed which considers both spatial and temporal re-mapping of Macroblocks(MBs) within a Group of Pictures (GOP). Moreover, a new prioritisation method to determine the concealment order of lost blocks is proposed. The new method uses the autocorrelation function as a measure to determine which blocks should be concealed first. The combined application of the novel ST-FMO and prioritisation scheme provides average gains of over of 2.34 dB over a conventional scheme and 1.11 dB over an existing FMO and prioritisation scheme.