multiple description coding has been receiving attention as a robust transmission framework for multimedia services. This paper studies the iterative decoding of FEC-based multipledescription codes. The proposed deco...
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multiple description coding has been receiving attention as a robust transmission framework for multimedia services. This paper studies the iterative decoding of FEC-based multipledescription codes. The proposed decoding algorithms take advantage of the error detection capability of Reed-Solomon (RS) erasure codes. The information of correctly decoded RS codewords is exploited to enhance the error correction capability of the Viterbi algorithm at the next iteration of decoding. In the proposed algorithm, an intradescription interleaver is synergistically combined with the iterative decoder. The interleaver does not affect the performance of noniterative decoding but greatly enhances the performance when the system is iteratively decoded. We also address the optimal allocation of RS parity symbols for unequal error protection. For the optimal allocation in iterative decoding, we derive mathematical equations from which the probability distributions of description erasures can be generated in a simple way. The performance of the algorithm is evaluated over an orthogonal frequency-division multiplexing system. The results show that the performance of the multipledescription codes is significantly enhanced.
In this article, a two-description distributed video coding (2D-DVC) is proposed to address the robust video transmission of low-power capturers. The odd/even frame-splitting partitions a video into two sub-sequences ...
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In this article, a two-description distributed video coding (2D-DVC) is proposed to address the robust video transmission of low-power capturers. The odd/even frame-splitting partitions a video into two sub-sequences to produce two descriptions. Each description consists of two parts, where part 1 is a zero-motion based H. 264-coded bitstream of a sub-sequence and part 2 is a Wyner-Ziv (WZ)-coded bitstream of the other sub-sequence. As the redundant part, the WZ-coded bitstream guarantees that the lost sub-sequence is recovered when one description is lost. On the other hand, the redundancy degrades the rate-distortion performance as no loss occurs. A residual 2D-DVC is employed to further improve the rate-distortion performance, where the difference of two sub-sequences is WZ encoded to generate part 2 in each description. Furthermore, an optimization method is applied to control an appropriate amount of redundancy and therefore facilitate the tuning of central/side distortion tradeoff. The experimental results show that the proposed schemes achieve better performance than the referenced one especially for low-motion videos. Moreover, our schemes still maintain low-complexity encoding property.
Presently, application layer multicast protocols (ALM) are proposed as substitute for IP multicast and have made extraordinary achievements. Integrated with Multi-data-stream mode such as multiple description coding (...
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Presently, application layer multicast protocols (ALM) are proposed as substitute for IP multicast and have made extraordinary achievements. Integrated with Multi-data-stream mode such as multiple description coding (MDC), ALM becomes more scalable and robust in high-dynamic Internet environment compared with single data stream. Although MDC can provide a flexible data transmission style, the synchronization of different descriptions encoded from one video source is proved to be difficult due to different delay on diverse transmission paths. In this paper, an ALM system called HMDC is proposed to improve accepted video quality of streaming media, hosts can join the separate overlay trees in different layers simultaneously, then the maximum synchronized descriptions of the same layer are worked out to acquire the best video quality. Simulations implemented on Internet-like topology indicate that HMDC achieves better video quality, lower link stress, higher robustness and comparable latency compared with traditional ALM protocols.
This paper proposes a novel and efficient two-description image coding scheme in the wavelet ***,each description includes one basic description produced by pairwise correlating transform (PCT) and one enhanced descri...
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This paper proposes a novel and efficient two-description image coding scheme in the wavelet ***,each description includes one basic description produced by pairwise correlating transform (PCT) and one enhanced description formed by quincunx ***,we partition the low-frequency wavelet coefficients into two *** the PCT was applied between the two groups to generate two new correlated groups as two basic descriptions,which are coded and transmitted through two separate ***,we can get two enhanced descriptions from the high-frequency wavelet coefficients of the highest-level decomposition by quincunx *** the Wavelet Domain Interpolation for tree Reconstruction (WDIR) is used to conceal coefficients loss in Wavelet-Trees when one enhanced description lost during *** results demonstrate that the proposed MDC scheme can achieve good coding performance.
Presently, application layer multicast protocols(ALM) are proposed as substitute for IP multicast and have made extraordinary achievements. Integrated with Multi-data-stream mode such as multiple description coding(MD...
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Presently, application layer multicast protocols(ALM) are proposed as substitute for IP multicast and have made extraordinary achievements. Integrated with Multi-data-stream mode such as multiple description coding(MDC)ALM becomes more scalable and robust in high-dynamic Internet environment compared with single data stream. Although MDC can provide a flexible data transmission style, the synchronization of different descriptions encoded from one video source is proved to be difficult due to different delay on diverse transmission paths. In this paper, an ALM system called HMDC is proposed to improve accepted video quality of streaming media, hosts can join the separate overlay trees in different layers simultaneously, then the maximum synchronized descriptions of the same layer are worked out to acquire the best video quality. Simulations implemented on Internet-like topology indicate that HMDC achieves better video quality, lower link stress, higher robustness and comparable latency compared with traditional ALM protocols.
multiple description coding (MDC) and forward error control (FEC) are two frequently used techniques for improving transport performance on lossy packet networks. Typically, these two techniques are used separately an...
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ISBN:
(纸本)9781424415632
multiple description coding (MDC) and forward error control (FEC) are two frequently used techniques for improving transport performance on lossy packet networks. Typically, these two techniques are used separately and independently with resulting performance dependent on network conditions' the choice of coding parameters and the applications being transported. In this paper we propose and analyze a joint MDC and FEC coding approach for delay-constrained applications on congested networks under some idealized modeling assumptions which are, nevertheless, sufficient to draw some qualitative conclusions. Specifically, for fixed delay constraints we show that under a range of operating parameters, there is an optimal FEC coding block size, channel coding rate and assignment of MDC rates which can achieve significantly improved end-to-end performance, compared to the performance achieved by using only MDC or FEC alone.
Almost all existing multi-descriptioncoding (MDC) schemes are designed for media streaming over Internet. In this work, a wavelet-based video MDC technique is introduced that fits the criteria of media streaming over...
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ISBN:
(纸本)9781424410934
Almost all existing multi-descriptioncoding (MDC) schemes are designed for media streaming over Internet. In this work, a wavelet-based video MDC technique is introduced that fits the criteria of media streaming over peer-to-peer networks. Our proposed method assigns descriptions to the senders due to their characteristic (Le. bandwidth and availability). In contrast to traditional MDC, different descriptions in the proposed method have different importance in remaking the original media. Our simulation results show considerable improvement of video quality at the receiver (up to 10 dB) as compared to the state-of-the-art.
multiple description coding (MDC) is a plausible way to use the diversity of packet networks to increase the robustness of the transmission to packet losses. The redundancy that is introduced via MDC can also be used ...
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ISBN:
(纸本)9781605603162
multiple description coding (MDC) is a plausible way to use the diversity of packet networks to increase the robustness of the transmission to packet losses. The redundancy that is introduced via MDC can also be used to increase the robustness of the transmission to bit-errors. This paper presents a novel decoding method for GMM (Gaussian Mixture Model)-based MDC in the presence of detected bit-errors. Particularly for speech transmission over bit-erasure channels, is is shown that the proposed method considerably improves the quality of the received speech spectral envelopes when one side-description is damaged. In highly correlated descriptions, for example, single and double bit-errors can almost be corrected.
In this paper a novel H.264 multipledescription technique is proposed. The coding approach is based on the redundant slice representation option, defined in the H.264 standard. In presence of losses, the redundant re...
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ISBN:
(纸本)9781424414369
In this paper a novel H.264 multipledescription technique is proposed. The coding approach is based on the redundant slice representation option, defined in the H.264 standard. In presence of losses, the redundant representation can be used to replace missing portions of the compressed bitstream, thus yielding a certain degree of error resilience. This paper addresses the creation of two balanced descriptions based on the concept of redundant slices, while keeping full compatibility with the H.264 standard syntax and decoding behavior. Moreover, a practical algorithm for redundancy tuning as a function of the packet loss rate is provided. Experimental results demonstrate that the proposed technique favorably compares with other H.264 multipledescription approaches.
This paper addresses the problem of video compression for robust transmission on lossy Internet networks. The approach developed relies on multiple description coding (MDC) principles. Predictive multipledescription ...
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This paper addresses the problem of video compression for robust transmission on lossy Internet networks. The approach developed relies on multiple description coding (MDC) principles. Predictive multipledescription video coding has already been considered for robust video transmission over lossy channels. However, MDC, when combined with motion-compensated prediction, is known to suffer from predictive mismatch: in presence of losses, the prediction signal available at the decoder may differ from the one used at the encoder. In this paper, we describe a video compression scheme based on MDC and Wyner-Ziv (WZ) coding. The input sequence is structured into groups of pictures which contain one key frame and one WZ frame. Each frame is first transformed with a wavelet transform and the resulting frequency bands are quantized with a multipledescription scalar quantizer. Two balanced descriptions of the video input are thus generated. The quantization indexes of the WZ frames are coded with an low-density parity-check accumulate-based Slepian-Wolf (SW) coder. The lateral receivers first decode the received key frame lateral descriptions, and then construct the side information needed for decoding the corresponding WZ frame descriptions by motion-compensated interpolation. In the case where the two WZ data descriptions are received, the central decoder can perform a separate SW decoding of the two sequences of quantization indexes. A joint iterative decoding approach of the two WZ descriptions is also described which improve the central WZ data decoding performance, however, at the expense of increased decoding complexity. The influence of the proposed iterative decoding technique and of the amount of redundancy on the lateral and central rate-distortion performance of the algorithm is studied.
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