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A low-complexity rate allocation algorithm for joint source-channel video coding

SIGNAL PROCESSING-IMAGE COMMUNICATION 2009年第5期24卷 368-383页

作者： Milani, Simone Calvagno, Giancarlo Univ Padua Dept Informat Engn I-35131 Padua Italy

The problem of enabling robust video transmission over lossy networks has become increasingly important because of the growing interest in video delivery over unreliable channels such as wireless networks. The more the coding process relies on an intensive use of prediction to improve the coding gain, the more the reconstructed sequence proves to be sensitive to information losses. As a matter of fact, it is necessary to introduce some redundant data in order to increase the robustness of the coded bit stream. A possible solution can be found filling a matrix structure with RTP packets and applying a Forward Error Correction (FEC) code on its rows. However, the matrix size and the chosen FEC code affect the performance of the coding system. The paper proposes a novel adaptation technique that tunes the amount of redundant information included in the packet stream and differs from previously proposed solutions since it relies on the percentage of null quantized transform coefficients in place of the activity or the Mean Square Error (MSE). This strategy is then integrated in a joint source-channel coder rate allocation algorithm that shares the available bits between the H.264/AVC coder and the channel coder according to the significance of the frame in the decoding process. Experimental results show that the presented approach significantly improves the quality of the reconstructed sequences at the decoder with respect to activity-based strategies and requires a low computational complexity. (C) 2009 Elsevier B.V. All rights reserved.

关键词： Video coding H.264/AVC joint source-channel coding Bit allocation R-D parameterization Low complexity

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joint source-channel turbo coding for binary Markov sources

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2006年第5期5卷 1065-1075页

作者： Zhu, Guang-Chong Alajaji, Fady Lawrence Technol Univ Dept Math & Comp Sci Southfield MI 48075 USA Queens Univ Dept Math & Stat Kingston ON Canada Queens Univ Dept Elect & Comp Engn Kingston ON Canada

We investigate the construction of joint source-channel (JSC) Turbo codes for the reliable communication of binary Markov sources over additive white Gaussian noise and Rayleigh fading channels. To exploit the source Markovian redundancy, the first constituent Turbo decoder is designed according to a modified version of Berrou's original decoding algorithm that employs the Gaussian assumption for the extrinsic information. Due to interleaving, the second constituent decoder is unable to adopt the same decoding method;so its extrinsic information is appropriately adjusted via a weighted correction term. The Turbo encoder is also optimized according to the Markovian source statistics and by allowing different or asymmetric constituent encoders. Simulation results demonstrate substantial gains over the original (unoptimized) Turbo codes, hence significantly reducing the performance gap to the Shannon limit. Finally, we show that our JSC coding system considerably outperforms tandem coding schemes for bit error rates smaller than 10(-4), while enjoying a lower system complexity.

关键词： joint source-channel coding turbo codes AWGN and Rayleigh fading channels Shannon limit Markov sources iterative decoding bit error rate

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DEEP LEARNING FOR joint source-channel coding OF TEXT

DEEP LEARNING FOR JOINT SOURCE-CHANNEL CODING OF TEXT

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IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Nariman Farsad Milind Rao Andrea Goldsmith Electrical Engineering Stanford University Stanford CA

ISBN: (纸本)9781538646595

We consider the problem of joint source and channel coding of structured data such as natural language over a noisy channel. The typical approach to this problem in both theory and practice involves performing source coding to first compress the text and then channel coding to add robustness for the transmission across the channel. This approach is optimal in terms of minimizing end-to-end distortion with arbitrarily large block lengths of both the source and channel codes when transmission is over discrete memoryless channels. However, the optimality of this approach is no longer ensured for documents of finite length and limitations on the length of the encoding. We will show in this scenario that we can achieve lower word error rates by developing a deep learning based encoder and decoder. While the approach of separate source and channel coding would minimize bit error rates, our approach preserves semantic information of sentences by first embedding sentences in a semantic space where sentences closer in meaning are located closer together, and then performing joint source and channel coding on these embeddings.

关键词： deep learning natural language processing joint source-channel coding Combined source-channel coding channel coding Natural Language Processing Machine Learning BLOCK LENGTH joints Bit error rate Error analysis source coding closer finite length

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joint source channel coding Via Statistical Mechanics: Thermal Equilibrium Between the source and the channel

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IEEE TRANSACTIONS ON INFORMATION THEORY 2009年第12期55卷 5382-5393页

作者： Merhav, Neri Technion Israel Inst Technol Dept Elect Engn IL-32000 Technion Haifa Israel

We examine the classical joint source-channel coding problem from the viewpoint of statistical physics and demonstrate that in the random coding regime, the posterior probability distribution of the source given the channel output is dominated by source sequences, which exhibit a behavior that is highly parallel to that of thermal equilibrium between two systems of particles that exchange energy, where one system corresponds to the source and the other corresponds to the channel. The thermodynamical entropies of the dual physical problem are analogous to conditional and unconditional Shannon entropies of the source, and so, their balance in thermal equilibrium yields a simple formula for the mutual information between the source and the channel output, that is induced by the typical code in an ensemble of joint source-channel codes under certain conditions. This formula, as well as the statistical-mechanical perspective that leads to it, form the main contribution of this paper. We also demonstrate how our results can be used in applications, like the wiretap channel, and how can it be extended to multiuser scenarios, like that of the multiple access channel.

关键词： Entropy joint source-channel coding mutual information statistical physics thermal equilibrium

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joint source-channel coding with Unequal Error Protection using Asymmetric Turbo Codes

Joint Source-Channel Coding with Unequal Error Protection us...

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International Conference on Advanced Communication Technology

作者： Hanxin WANG Cuitao ZHU Chengyi XIONG Shaoping CHEN Department of Electronics and Information Engineering South-Central University for Nationalities Wuhan China

ISBN: (纸本)9781467331487

In this paper, we devise an efficient joint source-channel coding scheme for robust image transmission over noisy channels. We firstly present a novel interleaver, named unequal row column cyclic cross interleaver, which could improve the error correction capability of turbo codes effectively. Secondly, we devise two types of asymmetric turbo codes which consist of the parallel concatenated turbo codes using two non-identical component encoders with the different constraint lengths and mixed types of generator polynomials. The presented asymmetric turbo codes can optimize the bit error rate of both water-fall region at low signal to noise ratio and error-floor region at high signal to noise ratio, they outperform the conventional symmetric turbo codes but with reduced decoding complexity. Finally, we propose a joint source-channel coding scheme based on unequal error protection using asymmetric turbo codes. This scheme can adaptively adopt different coding strategies, different interleavers of turbo codes, various decoding algorithms and appropriate decoding iterative numbers according to the different significant levels of image data streams and the varying conditions of estimated channel state information. The proposed scheme can also dynamically adjust the source compression ratios and channel code rates by optimizing the rate allocation according to the calculated peak signal to noise ratio of reconstructed images and the estimated channel states information. The experimental results show that the proposed joint source-channel coding scheme can evidently increase the peak signal to noise ratio of the reconstructed images and improve the visual effect of the images but with no additional bandwidth, the scheme is more adaptive and feasible.

关键词： joint source-channel coding Unequal error protection Asymmetric turbo codes Interleaver Bit error rate Water-fall Error-floor Peak signal to noise ratio

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joint source-channel multistream coding and optical network adapter design for video over IP

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IEEE TRANSACTIONS ON MULTIMEDIA 2002年第1期4卷 3-22页

作者： Chen, J Liu, KJR Univ Maryland Dept Elect & Comp Engn Syst Res Inst College Pk MD 20742 USA

In this paper, we present a panorama picture on how to achieve end-to-end video over IP services under the communication environments, consisting of backbone networks, hybrid access networks, and the end users. The paper consists of three equally weighted subtopics which cover some novel thoughts in designing and implementing the video over IP system in the different areas, namely, a Synchronous Optical NETwork (SONET) network adapter for backbone connections, the joint source-channel multistream coding in hybrid access networks, and the content-based source coding in the transform domain. We propose to link the three different problems associated with the hybrid networks, which have different characteristics and design requirements, to improve the critical performances in various areas of video over IP systems. The goal is to deliver video over IP networks in more cost-effective and reliable manner. IP/ATM over SONET is currently a commonly used backbone technique. In the first part of this paper, we present a flexible design and implementation of a SONET network adapter to carry IP traffic via optical fiber. Unlike many conventional designs, our single-chip implementation supports different data rates (OC-3, OC-12, and OC-48), carries IP traffic directly over fiber, achieves more flexible for multivendor interoperability, and provides bandwidth efficient designs at the lower system latency. Hybrid access-networks via wireline or wireless connections are most likely needed for last-mile services. In the second part of this paper, we propose a joint source-channel multfstream video coding scheme to combat the transmission errors under the harsh network conditions. On top of traditional error control techniques, the simulation results demonstrate that our multistream design outperform the conventional approaches by up to 5-7 dB under the harsh network conditions. To support our multistream video coding scheme, we need to access and manipulate video objects rather tha

关键词： content-based video coding error-resilient transmission joint source-channel coding optical network SONET streaming video video over IP

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Polarized Dropout: A Novel Deep joint source channel coding Scheme for Erasure channels

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IEEE COMMUNICATIONS LETTERS 2024年第9期28卷 1986-1990页

作者： Ren, Zichang Wang, Yiru Zhao, Yuping Peking Univ Sch Elect Beijing 100871 Peoples R China

This letter investigates the challenges encountered by deep joint source-channel coding in erasure channels. We explore the effectiveness of the widely adopted dropout technique in endowing deep neural networks with resilience against erasures. However, directly applying dropout at the channel layer introduces uncertainty into the neural network's training process, leading to performance degradation. To address this issue, we introduce the Polarized Dropout scheme and a novel network architecture that encodes analog symbols using the Walsh-Hadamard transform based on real-number field computation. Leveraging the polarization of symbol recovery probabilities, for a given erasure rate, a determined set of neurons will be assigned a dropout rate of 1, while the remainder are assigned a dropout rate of 0. Simulation results indicate a maximum enhancement of nearly 6dB in communication performance.

关键词： joint source-channel coding deep learning polar code erasure channel joint source-channel coding deep learning polar code erasure channel

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Rate-Adaptive joint source channel coding Using Deep Block-based Compressed Sensing 26

Rate-Adaptive Joint Source Channel Coding Using Deep Block-b...

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26th International Workshop on Multimedia Signal Processing

作者： Jarrahi, Mohammad Amin Bourtsoulatze, Eirina Abolghasemi, Vahid Univ Essex Sch Comp Sci & Elect Engn CSEE Colchester Essex England

ISBN: (纸本)9798350387261;9798350387254

This paper introduces a novel Rate-Adaptive Compressed Sensing-based joint source-channel coding scheme, termed RACS-JSCC, which leverages deep block-based CS to dynamically adjust the encoding rate based on available channel bandwidth and input image statistics. RACS-JSCC selects the encoding rate using both local and global statistics of the input image, alongside channel state information, prior to the feature extraction stage. This approach eliminates the transmission of redundant features and ensures the input image is encoded at an optimal rate. By training a deep learning-based JSCC encoder-decoder pair to operate across multiple rates and channel conditions, the proposed method eliminates the necessity for multiple models and enhances practical applicability in diverse communication environments. Our experimental results demonstrate that RACS-JSCC achieves superior performance in terms of image quality and robustness against varying channel conditions, making it a highly efficient solution for real-world wireless image transmission.

关键词： Wireless image transmission joint source-channel coding compressed sensing deep learning

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joint source-channel-NETWORK coding FOR BIDIRECTIONAL WIRELESS RELAYS

JOINT SOURCE-CHANNEL-NETWORK CODING FOR BIDIRECTIONAL WIRELE...

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IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： Luus, Francois P. S. Maharaj, Bodhaswar T. Univ Pretoria Dept Elect Elect & Comp Engn ZA-0002 Pretoria South Africa

ISBN: (纸本)9781457705397

The application of joint source-channel coding, based on fountain codes, in the broadcast timeslot of wireless two-way network coding is investigated in this paper. A computationally efficient subroutine is contributed to the implementation of the fountain compressor, and an error analysis is done. Motivated to develop a true joint source-channel-network code that compresses, adds robustness against channel noise and network codes two packets on a single bipartite graph and iteratively decodes the intended packet on the same Tanner graph, an adaptation of the fountain compressor is presented. The proposed code is shown to outperform a separated joint source-channel and network code in high source entropy and high channel noise regions.

关键词： joint source-channel coding joint source-channel-network coding two-way network coding fountain code lt-code

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Iterative decoder design for joint source-channel LDPC coding

Iterative decoder design for joint source-channel LDPC codin...

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International Conference on Computer as a Tool (EUROCON 2005)

作者： Lakovic, K Tian, T Villasenor, J Univ Calif Los Angeles Los Angeles CA 90024 USA

ISBN: (纸本)142440049X

We consider joint source-channel coding with variable length codes (VLCs) and LDPC codes. We propose an iterative source-channel decoding system, which involves message passing between a soft-input-soft-output VLC decoder and an LDPC decoder. The proposed system utilizes the residual redundancy of the variable length code during the iterative decoding process, and is expected to exhibit decoding convergence at a lower SNR relative to the system in which source and channel decoding are performed separately. We present computer simulation results that confirm the expected gain of the proposed system.

关键词： joint source-channel coding LDPC codes variable length codes

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