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multiple description coding and Recovery of Free Viewpoint Video for Wireless Multi-Path Streaming

IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING 2015年第1期9卷 151-164页

作者： Liu, Zhi Cheung, Gene Chakareski, Jacob Ji, Yusheng Grad Univ Adv Studies Natl Inst Informat Tokyo 1018430 Japan Univ Alabama Dept Elect & Comp Engn Tuscaloosa AL 35487 USA

By transmitting texture and depth videos captured from two nearby camera viewpoints, a client can synthesize via depth-image-based rendering (DIBR) any freely chosen intermediate virtual view of the 3D scene, enhancing the user's perception of depth. During wireless network transmission, burst packet losses can corrupt the transmitted texture and depth videos and degrade the synthesized view quality at the client. In this paper, we propose a multiple description coding system for multi-path transmission of free-viewpoint video, with joint interview and temporal description recovery capability. In particular, we encode separately the even frames of the left view and the odd frames of the right view, and transmit them as one description on one path. The second description comprises the remaining frames in the two views and is transmitted over a second path. If the receiver receives only one description due to burst loss in the other path, the missing frames in the other description are partially reconstructed using our frame recovery procedure. First, we construct two recovery candidates for each lost pixel in a frame. The first candidate is generated via temporal super-resolution from its predecessor and successor frames in the same view. The second candidate is generated via DIBR from the received frame of the same time instance in the other view. Next, we select the best pixel candidates one patch at a time, where an image patch corresponds to a neighborhood of pixels with similar depth values in the 3D scene. Near-optimal source and channel coding rates for each description are selected using a branch-and-bound method, for given transmission bandwidth on each path. Experimental results show that our system can outperform a traditional single-description/single-path transmission scheme by up to 5.5 dB in Peak Signal-to-Noise Ratio (PSNR) of the synthesized intermediate view at the client.

关键词： Free-viewpoints video multiple description coding wireless multi-path streaming depth-image-based rendering

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Perceptual multiple description coding with Randomly Offset Quantizers

Perceptual Multiple Description Coding with Randomly Offset ...

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Asia-Pacific Signal and Information Processing Association Annual Summit and Conference (APSIPA)

作者： Zong, Jingxiu Meng, Lili Tan, Yanyan Ren, Yuwei Shandong Normal Univ Dept Informat Sci & Engn Shandong Prov Key Lab Novel Distributed Comp Soft Jinan Peoples R China

ISBN: (纸本)9789881476821

A novel perceptual multiple description coding with randomly offset quantizers (PMDROQ) is proposed. In the proposed PMDROQ method, the input image is partitioned into M subsets, and then obtaining M descriptions. In each description, one subset is directly encoded and decoded with differentsmall perceptual quantization stepsizes in DCT domain, while other subsets are predictively coded and decoded with a large quantization stepsize. The perceptual quantization stepsize of low frequency coefficient is smaller than that of the high frequency coefficient. The proposed PMDROQ is applied to two-description lapped transform-based image coding. The experimental results show that the developed scheme obtains better performance than other methods in this category.

关键词： multiple description coding perceptual coding randomly offset quantizers

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multiple description coding for Encrypted Images 11

Multiple Description Coding for Encrypted Images

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11th International Conference on Intelligent Information Hiding and Multimedia Signal Processing (IIH-MSP)

作者： Zhang, Yuan Zhang, Xinpeng Qin, Chuan Yu, Jiang Shanghai Univ Sch Commun & Informat Engn Shanghai 200041 Peoples R China Huzhou Univ Sch Informat Engn Huzhou Peoples R China Univ Shanghai Sci & Technol Sch Opt Elect & Comp Engn Shanghai Peoples R China

ISBN: (纸本)9780769556680

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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Layered multiple description video coding using dual-tree discrete wavelet transform and H.264/AVC

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MULTIMEDIA TOOLS AND APPLICATIONS 2016年第5期75卷 2801-2814页

作者： Chen, Jing Cai, Canhui Li, Li Li, Cuihua Xiamen Univ Sch Informat Sci & Engn Xiamen Peoples R China Huaqiao Univ Sch Informat Sci & Engn Xiamen Peoples R China

A novel hybrid layered multiple description video coding (HLMDVC) algorithm is proposed to provide a robust and flexible video transmission via unreliable networks, like Internet or the wireless network. First, the input video sequence is encoded by a standard H.264/AVC encoder in low bit rate to form the base layer, which is then duplicated to each description. Second, the 3D dual-tree discrete wavelet transform is performed on the difference between the reconstructed base layer and the input sequence to produce four wavelet coefficient trees. Then the noise shaping is used to reduce the redundancy of these coefficient trees. After that, the four sparse wavelet coefficient trees are separately encoded by 3D-SPIHT encoders. The resulted four bitstreams are partitioned into two groups, separately forming enhancement layers of two descriptions. The redundancy of the proposed multiple description video coding scheme can be easily adjusted by changing the bitrate of the base layer to fit for different transmission channels. The directional selectivity feature of 3D dual-tree discrete wavelet transform frees the enhancement layer coding from the time consuming motion estimation, such that no mismatch happens and the coding efficiency is improved. Simulation results have shown that the quality of the reconstructed video of the proposed HLMDVC algorithm is superior to that by the state-of-the-art multiple description video coding methods.

关键词： multiple description coding Video coding Layered coding Dual-tree discrete wavelet transform H.264/AVC

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Coalitional Games for Determining Rate Region of multiple description coding

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IEEE COMMUNICATIONS LETTERS 2015年第1期19卷 34-37页

作者： Azimi, Seyyed Mohammadreza Isfahan Univ Technol Dept Elect & Comp Engn Esfahan *** Iran

To combat erasure channels, multiple description coding (MDC) introduces diversity at source coding level. Each description provides a coarse reconstruction of source information at destination. As the number of received description increases, the reconstruction quality would be improved. Rate region of MDC is the set of achievable rates for a given set of expected distortions. In this paper, coalitional game theory is proposed as a nontrivial approach for determining rate region of MDC. To this end, elaborate game theoretic analysis is provided. Moreover, Shapley value is utilized to determine each description's rate. As a result, a fair rate adjustment is obtained that comprises entropy and mutual information of original and reconstructed descriptions.

关键词： Coalitional game theory core multiple description coding Shapley value

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Adaptive error concealment for temporal-spatial multiple description video coding

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2016年 47卷 313-331页

作者： Yang, Meilin Gadgil, Neeraj Comer, Mary L. Delp, Edward J. Purdue Univ Sch Elect & Comp Engn Video & Image Proc Lab VIPER W Lafayette IN 47907 USA

With the development of 3G/4G and WiFi networks, there has been a growing demand for video delivery over wireless channels. This increase of video traffic creates a significant challenge for efficient, reliable and adaptable video coding techniques. multiple description coding (MDC) is an error resilient video coding method that has been proposed for streaming applications when retransmission is unacceptable. In this paper, we present error concealment approaches for two different four-description MDC architectures. In our first architecture, four descriptions are generated by temporal-spatial subsampling and encoded independently. To improve the error robustness, several adaptive error concealment methods are described. One of them is a frame-level method based on error tracking. It takes into account the distortion due to error concealment and error propagation. The other methods are macroblock-level methods based on foreground-background mapping and distortion mapping respectively. Our second MDC partition architecture aims at better coding efficiency and improved error robustness. Here spatial partitioning is done after prediction so that each of the two descriptions shares the same prediction loop. Experimental results are presented to demonstrate the efficacy of our proposed methods. (C) 2016 Elsevier B.V. All rights reserved.

关键词： multiple description coding Adaptive error concealment Temporal correlation Spatial correlation

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Graded Quantization for multiple description coding of Compressive Measurements

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IEEE TRANSACTIONS ON COMMUNICATIONS 2015年第5期63卷 1648-1660页

作者： Valsesia, Diego Coluccia, Giulio Magli, Enrico Politecn Torino Dept Elect & Telecommun I-10129 Turin Italy

Compressed sensing (CS) is an emerging paradigm for acquisition of compressed representations of a sparse signal. Its low complexity is appealing for resource-constrained scenarios like sensor networks. However, such scenarios are often coupled with unreliable communication channels and providing robust transmission of the acquired data to a receiver is an issue. multiple description coding (MDC) effectively combats channel losses for systems without feedback, thus raising the interest in developing MDC methods explicitly designed for the CS framework, and exploiting its properties. We propose a method called Graded Quantization (CS-GQ) that leverages the democratic property of compressive measurements to effectively implement MDC, and we provide methods to optimize its performance. A novel decoding algorithm based on the alternating directions method of multipliers is derived to reconstruct signals from a limited number of received descriptions. Simulations are performed to assess the performance of CS-GQ against other methods in presence of packet losses. The proposed method is successful at providing robust coding of CS measurements and outperforms other schemes for the considered test metrics.

关键词： Compressed sensing multiple description coding quantization

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A Selective Intra-coding Approach for multiple description Video coding 18

A Selective Intra-Coding Approach for Multiple Description V...

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18th IEEE International Symposium on Multimedia (IEEE ISM)

作者： Kazemi, Mohammad Iqbal, Razib Shirmohammadi, Shervin Univ Isfahan Dept Elect Engn Esfahan Iran Missouri State Univ Dept Comp Sci Missouri MO USA Univ Ottawa Sch EECS Ottawa ON Canada

ISBN: (纸本)9781509045716

multiple description coding (MDC) is a technique for video transmission over error prone networks where the descriptions are routed over multiple paths. Intra coding technique and MDC both provides error resiliency for real-time video transport over unreliable networks. In this paper, we present our investigation results for a new intra coding approach for MDC where selective frames are fully encoded in intra mode instead of coding selective macroblocks in intra mode in many frames. We implemented our scheme in the H.264/AVC reference software, JM16.0. Based on the experimental performance evaluation, we show that our method achieves higher average PSNR compared to the other optimized MDC schemes available in the literature.

关键词： multiple description coding intra coding error reslient coding

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Use of Spatial Division Scheme in multiple description coding Algorithm for Multipoint Videoconferencing

Use of Spatial Division Scheme in Multiple Description Codin...

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International Siberian Conference on Control and Communications (SIBCON)

作者： Tarakanov, Alexey Gushchina, Olga PG Demidov Yaroslavl State Univ Dept Phys Yaroslavl Russia

ISBN: (纸本)9781479971039

The paper presents analysis of multiple description coding (MDC) algorithm with spatial division of video stream into substreams. Two objective quality criteria Peak Signal-to-Noise Ratio (PSNR) and Video Quality Metric (VQM) were used for rating of video quality. In case when network losses affect on any video substreams full picture is restored with using of linear interpolation. Presented results demonstrate high efficiency of the MDC algorithm up to 50% losses of information.

关键词： multiple description coding videoconferencing video quality H.264

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Finding Acceptable Trade-off between Rate and Distortion in multiple description coding based on Zero Padding

Finding Acceptable Trade-off between Rate and Distortion in ...

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Workshop on Computer Architecture, Embedded Systems, SoC, and VLSI/EDA / International Computer Symposium (ICS)

作者： Chang, Rong-Hua Su, Chieh-Wei Lin, Chow-Sing Natl Univ Tainan Dept Comp Sci & Informat Engn Tainan 70005 Taiwan

ISBN: (纸本)9781614994848;9781614994831

In the studies related to multiple description coding (MDC), applying zero padding not only improves the spatial correlation between the descriptions but also increases the size. However, as we pad more zeros, the spatial correlation does not improves linearly. Therefore, the distortion is not reduced as the same amount as the size increases. In this paper we focus on how to efficiently find an acceptable trade-off between the number of padded zeros and the increase of distortion. Based on a MDC method named "multiple description coding with Zero Padding based on spatial Quincunx distribution (QZP-MDC)", in this paper we propose a distortion estimation, which is "Standard Deviation for Distortion Estimation (STD-DE)" to efficiently calculate the distortion with specific padding direction and the number of padded zeros. To search for the acceptable the number of padded zeros, we design two search methods, Naive Search and Best Division Search, based on the proposed rate-distortion trade-off indicator. Our experiment results show that errors of distortion estimation by STD-DE are all less than 2%, and the executing times by best division search is about twice faster more than those of naive search for 11 test sequences. To summarize our work, we confirm that the best division search on STD-DE can find the acceptable trade-off between rate and distortion in low computational complexity.

关键词： multiple description coding Zero Padding Rate-Distortion Trade-off

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