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Conference on Multimedia Systems and Applications IX

作者： Park, Sung-Bum Kim, Chang-Su Lee, Sang-Uk Seoul Natl Univ Signal Proc Lab Sch Elect Engn Seoul 151741 South Korea Korea Univ Sch Elect Engn Seoul South Korea

ISBN: (纸本)0819464899

A multiple description coding (MDC) technique for 3-D surface geometry is proposed in this work. The encoder uses a plane-based representation to describe point samples. Then, those plane primitives are classified into two disjoint subsets or two descriptions, each of which provides equal contribution in 3-D surface description. The two descriptions are compressed and transmitted over distinct channels. At the decoder, if both channels are available, the descriptions are decoded and merged together to reconstruct a high quality surface. If only one channel is available, we employ a surface interpolation method to fill visual holes and reconstruct a smooth surface. Therefore, the proposed algorithm can provide an acceptable reconstruction even though one channel is totally lost. Simulation results demonstrate that the proposed algorithm is a promising scheme for 3-D data transmission over noisy channels.

关键词： 3-D point clouds plane-based representation error-resilient technique multiple description coding

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Influence of Packets Losses on Video Quality in Case of Using multiple description coding with Time Division into Two and Three Substreams 17

Influence of Packets Losses on Video Quality in Case of Usin...

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Conference of Open Innovations Association FRUCT

作者： Tarakanov, Alexey Gushchina, Olga Nenakhov, Ilya PG Demidov Yaroslavl State Univ Yaroslavl Russia

ISBN: (纸本)9785757704937

The paper presents analysis of simultaneous use of multiple description coding (MDC) algorithm and multipath routing for IP-based videoconferencing system. Experimental results are given for time division of video stream in two and three substreams, compressed by H.264 codec with different quality factors (Q) and different packet loss rates in network (from 0% to 50%). Video quality is estimated with the use of two reference quality criterions: Peak Signal-to-Noise Ratio (PSNR) and Video Quality Metric (VQM).

关键词： Time division multiple description coding Videotapes Packet loss Peak signal-to-noise ratio Quality factor Packet

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multiple description coding for Encrypted Images

Multiple Description Coding for Encrypted Images

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International Conference on Intelligent Information Hiding and Multimedia Signal Processing

作者： Yuan Zhang Xinpeng Zhang Chuan Qin Jiang Yu School of Communication and Information Engineering Shanghai University Shanghai China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Shanghai China

ISBN: (纸本)9781509001897

This work proposes a novel multiple description coding (MDC) method for encrypted images transmitted over unreliable networks. Here, a pseudorandom permutation is used to mask the original content to protect privacy. The encoder splits the encrypted data into two descriptions, and each description includes different rigid pixels and coefficients generated from orthogonal transform to the elastic pixels. An acceptable quality reconstruction can be decodable from the side decoder through iteratively updating the values of coefficients based on the spatial correlation. At the central decoder, since the more accurate rigid pixels received, the more similar predicted image can be considered as initialization. Moreover, the operation of iterative reconstruction twice to unknown pixels also makes the estimations closer to the real values. Therefore, a high quality reconstruction from multiple descriptions can be obtained at the central decoder. Comparison is made with the single description coding and the experiments result is shown that the reconstruction performance with the multiple description coding for encrypted images is significantly improved.

关键词： encrypted image image transmission multiple description coding

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SLICE-LEVEL RATE-DISTORTION OPTIMIZED multiple description coding FOR H.264/AVC

SLICE-LEVEL RATE-DISTORTION OPTIMIZED MULTIPLE DESCRIPTION C...

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2010 IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Peraldo, L. Baccaglini, E. Magli, E. Olmo, G. Ansari, R. Yao, Y. Politecn Torino Dipartimento Elettron Turin Italy Univ Illinois Chicago IL 60680 USA

ISBN: (纸本)9781424442966

We propose a novel standard-compliant multiple description coding (MDC) method that exploits the H.264/AVC redundant slice tool, performing rate-distortion optimization at the slice level. The strategy to allocate redundancy to each slice jointly takes into account its contribution to distortion, its position in the GOP, the effect of decoder error concealment, and the transmission conditions. This makes the algorithm more accurate with respect to previous frame-based solutions, and experimental results show that it compares favorably with other state-of-the-art standard-compliant MDC techniques.

关键词： multiple description coding H.264/AVC

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Error Resilient Transmission for Compressed Sensing of Color Images with multiple description coding 3

Error Resilient Transmission for Compressed Sensing of Color...

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International Conference on Robot Vision and Signal Processing

作者： Huang, Hsiang-Cheh Chen, Po-Liang Chang, Feng-Cheng Natl Univ Kaohsiung Dept Elect Engn Kaohsiung 811 Taiwan Tamkang Univ Dept Innovat Informat & Technol Ilan 262 Taiwan

ISBN: (纸本)9781467396462

Compressed sensing (CS), due to its superior performances that very few amounts of coefficients are capable of reconstructing the image with reasonable quality, is an effective means in data compression in recent years. For the transmission of image compressed with CS, due to the channel errors that may be experienced, data protection would be required. We employ multiple description coding (MDC) for protecting color images with compressed sensing. With MDC, compressed information can be divided into different chunks at the encoder, and all the chunks can be transmitted over multiple independent channels to alleviate the influences caused by channel errors. At the decoder, the possibly corrupted chunks are assembled together, and MDC can be applied to reconstruct the image. With our algorithm, simulation results presented the error resilient capability and improved quality of color images.

关键词： compressed sensing multiple description coding color image image quality

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multiple description coding with Delta-Sigma Modulation

Multiple Description Coding with Delta-Sigma Modulation

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IEEE 10th International Conference on Industrial Informatics(第十届IEEE工业信息学国际学术会议 INDIN2012)

作者： Ryuta Shiomi Daiki Abe Takahiro Yakoh Department ofSystem Design EngineeringKeio University Yokohama Japan Department of System Design Engineering Keio University Yokohama Japan

ISBN: (纸本)9781467303125

multiple description coding (MDC) can be applied for multipath communication to reduce the negative affect of packet loss, and it is composed of three processes: encoding, quantizing, and decoding. Encoding and decoding are well researched in MDC, but there are few researches that focus on the quantization process. Therefore, this paper focuses on the quantization process of MDC. The aim of this paper is to improve the quality of the received data, and to reduce the bit width by employing static quantization (uniform quantization) with dynamic quantizer (△∑ modulation). Performance evaluation was done using a block diagram input module XCos which is attached to the formula processing software Scilab. As a result of using the △∑ modulation, the distortion improved by 95.2％ when both of the descriptions were received, and 45.3％ when only one of the description was received. Also, the experimental result showed that the quantization bit width can be reduced from 8 bit to 6 bit when the △∑ modulation was used.

关键词： multiple description coding MDC dynamical quantization delta-sigma modulation

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Optimal bit allocation for channel-adaptive multiple description coding

Optimal bit allocation for channel-adaptive Multiple Descrip...

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Conference on Image and Video Communications and Processing 2000

作者： Sagetong, P Ortega, A Univ So Calif Dept Elect Engn Syst Signal & Image Proc Inst Integrated Media Syst Ctr Los Angeles CA 90089 USA

ISBN: (纸本)0819435929

multiple description coding (MDC) techniques have been explored in recent years as an alternative to other methods to provide robustness to multimedia information in the presence of losses. In a MDC approach some redundancy is preserved in the source coding so that, after appropriate packetization, if packet losses occur it is possible to recover by exploiting the redundancy (statistical or deterministic) between what was received and what was lost. While MDC techniques have shown some promising results, one potential drawback is the fact that changing their redundancy level may entail significant changes to the system. Since the level of redundancy should be adjusted to match the specific channel conditions, the difficulty in adapting can be a significant problem for time varying transmission scenarios. As an example, MDC techniques based on transform coding would require a modification of the transform at encoder and decoder each time the channel conditions change. In our previous work,we have proposed a simple approach for MDC that involves using a polyphase transform and deterministic redundancy (e.g., each sample of input data is transmitted several times, with different coding rates). This approach is useful in that it greatly simplifies the design of a MDC scheme, since the rate allocation determines the amount of redundancy Moreover, it provides a great deal of flexibility as it enables the choice of redundancy to be almost arbitrary. To demonstrate the effectiveness of our system we introduce an optimal bit allocation algorithm that allows us to select the amount of redundancy to be introduced in the signal that best matches a given target packet loss rate. Iris clear that such a trade-off exists, as the level of redundancy should increase when the packet loss rate increases, at the cost of some degradation in the corresponding error free performance. Our results show significant differences between optimal and suboptimal choices of redundancy. Moreover, gi

关键词： bit allocation multiple description coding adaptive channel error protection

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multiple description coding and Forward Error Correction Concealment Methods for ACELP Coders in Packet Networks

Multiple Description Coding and Forward Error Correction Con...

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International Conference on Image and Signal Processing and their Applications (ISPA)

作者： Hocine Chaouch Fatiha Merazka LISIC Lab. Telecommunications Department USTHB University Algiers Algeria

ISBN: (纸本)9781728131573

In Voice over Iternet Protocol (VoIP) applications, paquet loss is major source of speech impairement. This work consists on using packet loss concealment methods based on multiple description coding (MDC) and Forward Error Correction (FEC) to improve speech quality deterioration caused by packet losses for Code-Excited Linear Prediction (CELP) based coders in packet network. We applied our approach to the standard ITU-T G.722.2 standard speech coder to evaluate its performance. The Perceptual Evaluation of Speech Quality (PESQ) and Enhanced Modified Bark Spectral Distortion (EMBSD) tests under various packet loss conditions confirm that the proposed algorithm, namely MDC is superior to the concealment algorithm embedded in the G.722.2. The performance measures demonstrate that the concealment method based FEC is better than interleaving and MDC methods at the expense of extra delay.

关键词： VoIP ITU-T g722.2 MDC FEC Markov model PESQ EMBSD PESQ multiple domain controllers CCL22 gene Packet switched networks FEC Regimen Voice over Internet Protocol Packet loss multiple description coding Data Security Forward error correction Markov models ENCODER ACELP

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multiple description coding algorithms for H.264 coder 07

Multiple description coding algorithms for H.264 coder

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Proceedings of the 3rd international conference on Mobile multimedia communications

作者： Marco Folli Lorenzo Favalli Università di Pavia Pavia Italy

ISBN: (纸本)9789630626705

In this paper we address the problem of video transmission over unreliable networks. The proposed approach moves from the concept of multiple description coding (MDC) introducing some simple algorithms to obtain sub-streams introducing the concepts of either spatial, temporal, SNR adaptation. The proposed algorithms have been implemented as pre- post- processing of the basic H.264/SVC codec. Although in principle as many descriptions as desired can be generated, simulation results using only two description show good results both when all descriptions are received and when only one of the two is received. Analysis performed in case of either random or packet losses show the robustness of the algorithms.

关键词： scalability H.264 multiple description coding

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NEW METHOD OF multiple description coding FOR IMAGE BASED ON COMPRESSED SENSING

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JOURNAL OF INFRARED AND MILLIMETER WAVES 2009年第4期28卷 298-302页

作者： Liu Dan-Hua Shi Guang-Ming Zhou Jia-She Gao Da-Hua Wu Jia-Ji Xidian Univ Minist Educ Key Lab Intelligent Percept & Image Understanding Xian 710071 Peoples R China AF Engn Univ Sch Sci Xian 710051 Peoples R China

Based on compressed sensing (CS), a new multiple description coding method (CS-MDC) was presented. The new method is robust to packet loss or bit error, and has the advantages of simple structure and easy implementation. The method partitioned an-image into several blocks by interleaving extracting in the wavelet domain, and made random measurements of the image blocks, and then formed multiple descriptions after quantizing and packing. At the decoding end, it reconstructed the original image approximately or exactly with the received bit streams by solving an optimization problem. The proposed method can construct more descriptions with lower complexity because the process of random measuring is simple and easy to realize. Experimental results show that the proposed method exhibits its superiority over SPIHT-MDC with the same packet loss probability, and it can easily generate more descriptions.

关键词： multiple description coding compressed sensing random measurement optimization problem

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