multiple description coding is a source coding technique that produces several descriptions of a single information source, such that various reconstruction qualities are obtained from different subsets of the descrip...
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multiple description coding is a source coding technique that produces several descriptions of a single information source, such that various reconstruction qualities are obtained from different subsets of the descriptions. It thus can provide error resilience to information transmitted on lossy networks. Among previous works, MDs for image coding were generated via polyphase transform and selective quantization, performed in the wavelet domain. In this pa- per, we present an effective way to exploit the special statistical properties of the wavelet decomposition to provide improved coding efficiency, in the same general framework. We propose a novel coding scheme that efficiently utilizes contextual information, extracted from another polyphase component, to improve the coding efficiency of each redundant component. Our experimental results demonstrate that the proposed coder outperforms its predecessor across the entire redundancy range, and that the improvement in coding efficiency can indeed be attributed primarily to the effective utilization of contextual information.
For two-description image coding, a conventional scheme is to partition an image into two parts and then to produce each description by alternatively concatenating a finely coded bitstream of one part and a coarsely c...
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For two-description image coding, a conventional scheme is to partition an image into two parts and then to produce each description by alternatively concatenating a finely coded bitstream of one part and a coarsely coded bitstream of the other part. This letter presents a new two-description image coding approach using steganography. Specifically, we propose forming each description by embedding (hiding) the coarsely coded part into the finely coded part based on a least-significant bit (LSB) steganographic method. In this way, the bit budget for the coarsely coded part in each description can be saved with little reconstruction degradation for the finely coded part if the embedding process is well designed. The experimental results substantiate the effectiveness of the proposed method.
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.
multiple description coding （MDC） generates multiple decodable bitstreams for a source to combat informa- tion loss. In this paper, multipath routing problem for two-description coded images is investigated for trad...
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multiple description coding （MDC） generates multiple decodable bitstreams for a source to combat informa- tion loss. In this paper, multipath routing problem for two-description coded images is investigated for traditional and coded wireless networks without and with coding capability at intermediate nodes, respectively. Firstly, we formulate an interference-aware MDC multipath routing for traditional networks by employing a time-division link scheduling method to eliminate wireless interference, and ultimately obtain an optimal path selection corresponding to the minimum achievable distortion. Secondly, for coded networks, we evaluate practical wireless network coding （NC） in delivering descriptions of multiple unicast sessions. While NC increases maximum supporting flow rate of MDC descriptions in wireless networks, possible undecodability of NC mixed information is alleviated by MDC. To minimize achievable distortion, a proposed interference-and-coding-aware MDC multipath routing strikes a good balance between minimizing side effect of wireless interference avoidance and maximizing NC opportunity. Simulation results validate the effectiveness of the two proposed schemes.
In this work we present an end-to-end optimized video streaming system comprising of synergistic interaction between a source packetization strategy and an efficient and responsive, TCP-friendly congestion control pro...
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In this work we present an end-to-end optimized video streaming system comprising of synergistic interaction between a source packetization strategy and an efficient and responsive, TCP-friendly congestion control protocol [Linear Increase Multiplicative Decrease with History (LIMD/H)]. The proposed source packetization scheme transforms a scalable/layered video bitstream so as to provide graceful resilience to network packet drops. The congestion control mechanism provides low variation in transmission rate in steady state and at the same time is reactive and provably TCP-friendly. While the two constituent algorithms identified above are novel in their own right, a key aspect of this work is the integration of these algorithms in a simple yet effective framework. This "application-transport" layer interaction approach is used to maximize the expected delivered video quality at the receiver. The integrated framework allows our system to gracefully tolerate and quickly react to sudden changes in the available connection capacity due to the onset of congestion, as verified in our simulations.
This paper presents TURINstream, a novel P2P video streaming architecture designed to jointly achieve low delay, robustness to peer churning, limited protocol overhead, and quality-of-service differentiation based on ...
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This paper presents TURINstream, a novel P2P video streaming architecture designed to jointly achieve low delay, robustness to peer churning, limited protocol overhead, and quality-of-service differentiation based on peers cooperation. Separate control and video overlays are maintained by peers organized in clusters that represent sets of collaborating peers. Clusters are created by means of a distributed algorithm and permit the exploitation of the participant nodes upload capacity. The video is conveyed with a push mechanism by exploiting the advantages of multiple description coding. TURINstream design has been optimized through an event driven overlay simulator able to scale up to tens of thousands of peers. A complete prototype of TURINstream has been developed, deployed, and tested on PlanetLab. We tested our prototype under varying degree of peer churn, flash crowd arrivals, sudden massive departures, and limited upload bandwidth resources. TURINstream fulfills our initial design goals, showing low average connection, startup, and playback delays, high continuity index, low control overhead, and effective quality-of-service differentiation in all tested scenarios.
We investigate the problem of robust video transmission over lossy packet networks. A resilient video coding framework is important to ensure quality video over these networks. We propose a combination of a rate-disto...
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We investigate the problem of robust video transmission over lossy packet networks. A resilient video coding framework is important to ensure quality video over these networks. We propose a combination of a rate-distortion optimized multipledescription codec and an integrated packetization method to constitute the error resilient codec. multipledescription (MD) coding techniques utilize path-diversity (multiple paths between sender and receiver) in networks by sending the descriptions along different paths. Two different optimization controls for the MID codec are proposed that are suited to variable rates of packet loss for multipath transmission of the MD coded video. An optimized strategy for packetizing the descriptions is also proposed which guarantees that each packet is self-contained and efficient. Simulations done under various packet loss scenarios show the need for two different optimization strategies and also that the developed MD codec achieves significantly improved video quality when compared with similar techniques.
The capacity region of the multicast Cognitive Inter-Ference Channel (CIFC) is investigated. This channel consists of two independent transmitters that wish to multicast two different messages, each to a different set...
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The capacity region of the multicast Cognitive Inter-Ference Channel (CIFC) is investigated. This channel consists of two independent transmitters that wish to multicast two different messages, each to a different set of users. In addition, one of the transmitters-commonly referred to as the cognitive transmitter-has prior non-causal knowledge of both messages to be transmitted. This scenario subsumes some long-standing open problems, such as the interference channel, the broadcast channel, and multicast communications. The aim of this paper is the derivation of optimal interference mitigation techniques under different interference regimes. To this end, two settings, namely the multi-primary CIFC, i.e., M = 1 and N >= 1, and its complementary, the multi-secondary CIFC, i.e., N = 1 and M >= 1, are investigated as an attempt to build a thorough understanding for the more general multicast CIFC setting. It is shown that, for some interference regimes, well-known coding techniques for the standard CIFC remain still optimal under the constraint of multicasting to multiple users. However, in other interference regimes, capacity achieving coding and decoding schemes prove to be more involved. A careful combination of these coding schemes and new outer bounding techniques allows to characterize the capacity region for several classes of discrete memoryless and Gaussian multicast CIFC under different interference regimes.
This paper presents a packet loss recovery method that uses an incomplete secondary encoding based on scalar quantization as redundancy. The method is redundancy bit rate scalable and allows an adaptation to varying l...
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This paper presents a packet loss recovery method that uses an incomplete secondary encoding based on scalar quantization as redundancy. The method is redundancy bit rate scalable and allows an adaptation to varying loss scenarios and a varying packeting strategy. The recovery is performed by minimum mean squared error estimation incorporating a statistical model for the quantizers to facilitate real.-time adaptation. A bit allocation algorithm is proposed that extends 'reverse water filling' to the problem of scalar encoding dependent variables for a decoder with a final estimation stage and available side information. We apply the method to the encoding of line-spectral frequencies (LSFs), which are commonly used in speech coding, illustrating the good performance of the method.
A peer-to-peer (P2P) architecture for multipoint video conferencing using layered video coding at the end hosts is proposed. The system primarily targets end points with low bandwidth network connections and enables t...
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A peer-to-peer (P2P) architecture for multipoint video conferencing using layered video coding at the end hosts is proposed. The system primarily targets end points with low bandwidth network connections and enables them to create a multipoint video conference without any additional networking and computing resources beyond what is needed for a point-to-point conference. For P2P multipoint video conferencing applications, wide-area collaboration is significant for connecting participants from different parts around the globe to support collaborative work. In our system, peers collaborate for streaming video, and the motivation behind the use of layered video is to overcome the problem of denying video requests by peers and assure that each participant peer can view any other participant at any configuration. Layered video encoding techniques usable within this architecture are discussed. A protocol for operating the system has been developed, simulated and its performance has been analyzed. Furthermore, a multi-objective optimization approach has been developed to simultaneously minimize the number of base layer receivers and the delay experienced by the peers while maximizing the granted additional requests to support peers having multiple video input bandwidths. The use of the multi-objective optimization scheme is demonstrated through an example scenario and simulations. A prototype has also been implemented, and the system has been formally specified and verified. (C) 2010 Elsevier Ltd. All rights reserved.
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