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Lapped orthogonal transforms designed for error-resilient image coding

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2002年第9期12卷 752-764页

作者： Chung, DM Wang, Y New York City Dept Transportat Sunnyside NY 11104 USA Polytech Inst New York Dept Elect & Comp Engn Brooklyn NY 11201 USA

This paper describes a new design method for lapped orthogonal transforms (LOTS) that can provide a desired tradeoff between coding efficiency and resilience to transmission errors. Traditionally, LOT bases have been designed to maximize the coding efficiency solely. When certain coefficients are lost due to impairments in the transmission channel, the reconstructed image is often unsatisfactory. Previously, we have developed a maximally smooth recovery method for the reconstruction of images from incomplete LOT coefficients. The reconstruction quality depends on the LOT basis used. In this paper, we describe a new LOT-basis design method, which maximizes the weighted average of a coding gain and a reconstruction gain, with the latter being defined according to the maximally smooth recovery method. A coder using the designed basis with a high weighting factor toward the reconstruction gain can achieve significantly better reconstruction quality than a LOT basis that is designed to optimize the coding efficiency only. The newly designed bases are evaluated by their redundancy-rate-distortion performance. Simulation results show that the new bases are more efficient than the bases designed previously by Hemami, in that the new bases require fewer redundancy bits to achieve the same reconstruction quality under the same channel error pattern.

关键词： rrror resilience image coding lapped orthogonal transforms multiple description coding

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Bandwidth-Agile Image Transmission With Deep Joint Source-Channel coding

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2021年第12期20卷 8081-8095页

作者： Kurka, David Burth Gunduz, Deniz Imperial Coll London Dept Elect & Elect Engn London SW7 2AZ England

We propose deep learning based communication methods for adaptive-bandwidth transmission of images over wireless channels. We consider the scenario in which images are transmitted progressively in layers over time or frequency, and such layers can be aggregated by receivers in order to increase the quality of their reconstructions. We investigate two scenarios, one in which the layers are sent sequentially, and incrementally contribute to the refinement of a reconstruction, and another in which the layers are independent and can be retrieved in any order. Those scenarios correspond to the well known problems of successive refinement and multiple descriptions, respectively, in the context of joint source-channel coding (JSCC). We propose DeepJSCC-l, an innovative solution that uses convolutional autoencoders, and present three architectures with different complexity trade-offs. To the best of our knowledge, this is the first practical multiple-description JSCC scheme developed and tested for practical information sources and channels. Numerical results show that DeepJSCC-l can learn to transmit the source progressively with negligible losses in the end-to-end performance compared with a single transmission. Moreover, DeepJSCC-l has comparable performance with state of the art digital progressive transmission schemes in the challenging low signal-to-noise ratio (SNR) and small bandwidth regimes, with the additional advantage of graceful degradation with channel SNR.

关键词： Image transmission joint source-channel coding multiple description coding successive refinement wireless communication

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multiple description video multicast in wireless ad hoc networks

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MOBILE NETWORKS & APPLICATIONS 2006年第1期11卷 63-73页

作者： Mao, SW Cheng, XL Hou, YT Sherali, HD Virginia Tech Bradley Dept Elect & Comp Engn Blacksburg VA 24061 USA Virginia Tech Grad Dept Ind & Syst Engn Blacksburg VA 24061 USA

multiple description (MD) coding is a new video coding technique that is uniquely suitable for video transport over wireless ad hoc networks. In this paper, we consider the problem of how to support video multicast with MD video in ad hoc networks. We follow an application-centric, cross-layer routing approach with the objective of minimizing the overall video distortion. We propose an MD video multicast scheme where multiple source trees are used. Furthermore, each video description is coded into multiple layers in order to cope with diversity in wireless link bandwidths. Based on this multicast model, we formulate the cross-layer multicast routing as a combinatorial optimization problem and propose an efficient Genetic Algorithm (GA)-based metaheuristic solution procedure. Performance comparison with existing approaches show significant gains for a wide range of network operating conditions.

关键词： cross-layer design genetic algorithms multiple description coding routing video multicast wireless ad hoc networks

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System Scheduling for Multi-description Video Streaming Over Wireless Multi-Hop Networks

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IEEE TRANSACTIONS ON BROADCASTING 2009年第4期55卷 731-741页

作者： Zhou, Liang Geller, Benoit Zheng, Baoyu Wei, Anne Cui, Jingwu ENSTA ParisTech UEI F-75015 Paris France Nanjing Univ Posts & Telecommun Inst Signal Proc & Transmiss Nanjing 210003 Peoples R China Univ Toulouse 2 F-31703 Blagnac France

Providing real-time multimedia applications over wireless multi-hop networks is a challenging problem because the wireless channels are highly sensitive to delay, interference and topology changes. multiple description coding (MDC), as a new emerging error-resilient technique, has been widely used recently in wireless video transmission. Its fundamental principle is to generate multiple correlated descriptions such that each description approximates the source information with a certain level of fidelity. Inevitably, MDC introduces many description streams which may influence each other and thus, reasonable system scheduling is needed to provide a satisfied video quality. The novelty of this work is to investigate the optimal distributed scheduling for multiple competing MDC streams in a resource-limited wireless multi-hop network. This is achieved by joint optimization of MDC, rate control and multipath routing. Two joint optimal algorithms, namely a distributed rate control and routing (DRCR) and a simplified DRCR algorithm, are proposed to solve this problem with constraints that arise from the multiple description streams among multiple users via multiple paths. Both algorithms are designed in a distributed manner that is amenable to on-line implementation for wireless networks. Theoretical analysis and simulation results are provided which demonstrate the effectiveness of our proposed joint schemes.

关键词： Multipath routing multiple description coding rate control video transmission

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LMDC: Learning a multiple description codec for deep learning-based image compression

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MULTIMEDIA TOOLS AND APPLICATIONS 2022年第10期81卷 13889-13910页

作者： Zhao, Lijun Zhang, Jinjing Bai, Huihui Wang, Anhong Zhao, Yao Taiyuan Univ Sci & Technol 66 Waliu Rd Taiyuan 030051 Shanxi Peoples R China North Univ China 3 Xueyuan Rd Taiyuan 030051 Shanxi Peoples R China Beijing Jiaotong Univ 3 Shangyuancun Haidian Dist Beijing 100044 Peoples R China

Although deep learning technique has been widely leveraged to compress image, few attentions are paid to multiple description (MD) coding based on this technique. Meanwhile, packet loss and bit error may occur inevitably during transmission over unreliable networks, which seriously corrupts image quality. Thus, we introduce a deep multiple description coding (MDC) framework for low bit-rate image compression, which is optimized according to deep MD rate-distortion minimization. Our framework includes MD multi-scale encoder network, MD cascaded-Resblock decoder networks, and arithmetic codec as well as a pair of learnable scalar quantizers and conditional probability models. In encoder, a pair of MD tensors are firstly generated by MD multi-scale encoder network, after which these tensors are discretized by a pair of learnable scalar quantizers respectively. Then, these quantized tensors are fed into conditional probability models for soft entropy estimation to regularize the learning of our encoder and decoder network during training, while these quantized tensors are lossly coded by arithmetic coding during testing. In decoder, these quantized tensors are decoded from bit-streams and then they are decompressed by MD cascaded-Resblock decoder networks for image decoding. To greatly reduce the total amount of network parameters, we design an auto-encoder network composed of these encoder and decoder networks with a symmetrical parameter sharing structure. Additionally, considering image spatial variation, each scalar quantizer is accompanied by an importance-indicator map to generate MD tensors, rather than using direct quantization. Experimental results have demonstrated that our MDC framework performs better than several existing MDC approaches in terms of several image quality metrics.

关键词： multiple description coding Scalar quantizer Auto-encoder Symmetrical sharing

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TuBeck: a novel peer-to-peer streaming system with Loopback-MDC for scalable H.264/AVC videos

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MULTIMEDIA TOOLS AND APPLICATIONS 2014年第2期72卷 1653-1679页

作者： Lin, Chow-Sing Chang, Rong-Hua Lin, Jhe-Wei Natl Univ Tainan Dept Comp Sci & Informat Engn Tainan 700 Taiwan

With the rapidly development of broadband networks, more and more users nowadays tend to acquire their desired videos from media-on-demand servers. How to efficiently provide multimedia contents for a large number of heterogeneous users on the Internet has become a noticeable issue. In our previous work, we proposed the Loopback-MDC scheme on CDN-P2P network to address such a scalability issue. In this paper, we present the design and implementation of a novel peer-to-peer streaming system with the Loopback-MDC on actual networks, named TuBeck. The TuBeck consists of preprocessor, server, peer, and player modules with the support of network infrastructure library. In TuBeck, multimedia sources are preprocessed to multiple descriptions. Each description is divided as a sequence of H.264/AVC chunks by modified JM encoder for real-time streaming. The network infrastructure library provides the nodes (server and peers) with the fundamental functionalities of network connections and communications. Message exchange and streaming control among nodes follow the pre-defined LM protocol. The server, peer, and player modules are functionally multithreaded in order to enhance the system performance. The experimental results show that the Loopback-MDC is practical for realizing a P2P streaming system in terms of the server loading, CPU/Memory usage, and efficiency of failure recovery with respect to various arrival rates, failure rates, and viewing qualities.

关键词： Streaming Peer-to-peer multiple description coding Loopback-MDC H.264

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Balanced dynamic buffering for scalable video-on-demand streaming on peer-to-peer networks

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MULTIMEDIA TOOLS AND APPLICATIONS 2013年第3期62卷 701-718页

作者： Lin, Chow-Sing Natl Univ Tainan Dept Comp Sci & Informat Engn Tainan 70005 Taiwan

In peer-to-peer video-on-demand streaming networks, the alleviation of server load depends on reciprocal stream sharing among peers. In general, on-demand video services enable clients to watch videos from beginning to the end in a pipeline fashion. As long as a client still caches the initial part of the video, it can provide on-demand service to the subsequent clients without intervention of a server. Therefore, the key challenge is how to maximize the availability of a video for stream relay by keeping the initial part of a video in a peer's buffer as long as possible. In addition, to address the issues of delivering data on lossy network and providing scalable video quality of services for clients, the adoption of multiple description coding has been proven as a feasible resolution by much research work. In this paper, we propose a novel caching scheme for P2P on-demand streaming called Balanced Dynamic Buffering with multiple description coding. The proposed balanced dynamic buffering gradually reduces the number of buffered descriptions once the buffer of a peer gets full. In addition, peers are grouped based on the number of descriptions cached in their buffer. The intra-group balancing and inter-group balancing are applied for well distributing descriptions and balancing their forwarding bandwidth on peer-to-peer on-demand streaming networks. In the paper, we also propose the failure recovery for the balanced dynamic buffering scheme. Simulation results showed that the balanced dynamic buffering significantly outperformed other dynamic buffering schemes and the CoopNet in server bandwidth utilization, and a longer buffer in a peer did favor the failure recovery on peer-to-peer on-demand streaming networks.

关键词： Streaming Video-on-demand Peer-to-peer multiple description coding Load balancing

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n-Channel Asymmetric Entropy-Constrained multiple-description Lattice Vector Quantization

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IEEE TRANSACTIONS ON INFORMATION THEORY 2010年第12期56卷 6354-6375页

作者： Ostergaard, Jan Heusdens, Richard Jensen, Jesper Aalborg Univ Aalborg Denmark Delft Univ Technol Delft Netherlands Oticon Copenhagen Denmark

This paper is about the design and analysis of an index-assignment (IA)-based multiple-description coding scheme for the n-channel asymmetric case. We use entropy constrained lattice vector quantization and restrict attention to simple reconstruction functions, which are given by the inverse IA function when all descriptions are received or otherwise by a weighted average of the received descriptions. We consider smooth sources with finite differential entropy rate and MSE fidelity criterion. As in previous designs, our construction is based on nested lattices which are combined through a single IA function. The results are exact under high-resolution conditions and asymptotically as the nesting ratios of the lattices approach infinity. For any n, the design is asymptotically optimal within the class of IA-based schemes. Moreover, in the case of two descriptions and finite lattice vector dimensions greater than one, the performance is strictly better than that of existing designs. In the case of three descriptions, we show that in the limit of large lattice vector dimensions, points on the inner bound of Pradhan et al. can be achieved. Furthermore, for three descriptions and finite lattice vector dimensions, we show that the IA-based approach yields, in the symmetric case, a smaller rate loss than the recently proposed source-splitting approach.

关键词： High-rate quantization index assignments lattice quantization multiple description coding

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On modeling mismatch errors induced by different quantizers

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IEEE SIGNAL PROCESSING LETTERS 2007年第11期14卷 785-788页

作者： Tillo, Tammam Grangetto, Marco Olmo, Gabriella Politecn Torino Dipartimento Elettron I-10129 Turin Italy

In this letter, the mismatch error due to the replacement of a fine with a coarse quantizer is considered, and an analytical model is proposed to describe the related distortion. Simulations show that this model is highly accurate and can be used to estimate the expected distortion of DPCM-based codecs in order to better allocating the rate. For highly correlated sources, this leads to a gain of 1 to 1.5 dB over an exhaustive search method that adopts a uniform redundancy allocation. Moreover, it permits to allocate the redundancy by an easy-to-solve analytical model of the system.

关键词： multiple description coding mismatch error distortion quantization mismatch redundant representations.

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Fast code-rate optimization for robust image transmission over lossy packet networks

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IEEE TRANSACTIONS ON COMMUNICATIONS 2005年第6期53卷 973-977页

作者： Grangetto, M Magli, E Olmo, G Politecn Torino Ctr Multimedia Radio Commun I-10129 Turin Italy

In this paper, we propose an efficient method for the allocation of Reed-Solomon codes to source symbols, for unequal loss protection. The proposed formulation recasts the multivariate optimization problem into a univariate one, dramatically reducing the computational complexity. Results are shown for image transmission over lossy packet networks, employing the JPEG2000 and SPIHT encoders. The proposed algorithm exhibits performance equivalent to previous methods, while providing a significant complexity reduction.

关键词： JPEG2000 multiple description coding Reed-Solomon codes SPIHT unequal loss protection

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