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IEEE International Conference on Image Processing (ICIP 2007)

作者： Gehrig, Nicolas Dragotti, Pier Luigi Univ London Imperial Coll Sci Technol & Med Dept Elect & Elect Engn Commun & Signal Proc Grp London SW7 2AZ England

ISBN: (纸本)9781424414369

In this paper, we propose a distributed compression approach for multi-view images, where each camera efficiently encodes its visual information locally without requiring any collaboration with the other cameras. Such a compression scheme can be necessary for camera sensor networks, where each camera has limited power and communication resources and can only transmit data to a central base station. The correlation in the multi-view data acquired by a dense multi-camera system can be extremely large and should therefore be exploited at each encoder in order to reduce the amount of data transmitted to the receiver. Our distributed source coding approach is based on a quadtree decomposition method and uses some geometrical information about the scene and the position of the cameras to estimate this multi-view correlation. We assume that the different views can be modelled as 2D piecewise polynomial functions with 1D linear boundaries and show how our approach applies in this context. Our simulation results show that our approach outperforms independent encoding of real multi-view images.

关键词： multi-view image compression distributed source coding camera sensor networks

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Multi-hypothesis based distributed video coding using LDPC codes 43

Multi-hypothesis based distributed video coding using LDPC c...

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43rd Annual Allerton Conference on Communication, Control and Computing 2005

作者： Misra, Kiran Karande, Shirish Radha, Hayder Department of Electrical and Computer Engineering 2120 Engineering Building Michigan State University East LansingMI United States

ISBN: (纸本)9781604234916

Conventional video coding paradigms are usually built on the assumption that a video stream will be encoded only once but decoded several times. Over the years, this has lead to the development of encoders, which use complex motion-estimation algorithms to reduce the size of the video bitstream. However in applications like distributed sensor networks, cell-phones etc. the encoder has a limited amount of resources available to it and cannot employ complex motion-estimation algorithms. Intracoded frames used in conventional video coding have low-complexity, however they need large bandwidth to be transmitted. This has led to the development of Wyner-Ziv video codecs [1] which are based on the principles of side-information based coding, first propounded in the 1970s by Slepian-Wolf and Wyner-Ziv in their seminal work [2] and [3] respectively. Wyner-Ziv video codecs perform intra-frame encoding at the transmitter, and inter-frame decoding at the receiver. This reduces the size of the intraframe considerably, at the cost of increasing complexity at the decoder. For video transmission using cell-phones this increased decoder complexity can be absorbed by the base stations. Current distributed video coding schemes achieve compression by using a single reference frame for side-information. This single reference frame could be the temporally adjacent picture frame, or on an interpolated frame constructed using temporally adjacent frames. This paper proposes a new scheme for decoding video using more than one video frame as reference. Unlike schemes which use an interpolated frame, our decoding scheme makes use of data directly from the reference frames, giving an improvement of up to 1 dB. The approach is based on the premise that, covered and uncovered region are better represented in the original side-information frames, compared to the interpolated frame. This is especially true for sequences which do not have low-motion content.

关键词： Channel Codes distributed source coding Multi-hypothesis

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Layered Wyner-Ziv video coding: a new approach to video compression and delivery

Layered Wyner-Ziv video coding: a new approach to video comp...

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作者： Xu, Qian Texas A&M University

Following recent theoretical works on successive Wyner-Ziv coding, we propose a practical layered Wyner-Ziv video coder using the DCT, nested scalar quantiza- tion, and irregular LDPC code based Slepian-Wolf coding (or lossless source coding with side information at the decoder). Our main novelty is to use the base layer of a standard scalable video coder (e.g., MPEG-4/H.26L FGS or H.263+) as the decoder side information and perform layered Wyner-Ziv coding for quality enhance- ment. Similar to FGS coding, there is no performance di®erence between layered and monolithic Wyner-Ziv coding when the enhancement bitstream is generated in our proposed coder. Using an H.26L coded version as the base layer, experiments indicate that Wyner-Ziv coding gives slightly worse performance than FGS coding when the channel (for both the base and enhancement layers) is noiseless. However, when the channel is noisy, extensive simulations of video transmission over wireless networks conforming to the CDMA2000 1X standard show that H.26L base layer coding plus Wyner-Ziv enhancement layer coding are more robust against channel errors than H.26L FGS coding. These results demonstrate that layered Wyner-Ziv video coding is a promising new technique for video streaming over wireless networks. For scalable video transmission over the Internet and 3G wireless networks, we propose a system for receiver-driven layered multicast based on layered Wyner-Ziv video coding and digital fountain coding. Digital fountain codes are near-capacity erasure codes that are ideally suited for multicast applications because of their rate- less property. By combining an error-resilient Wyner-Ziv video coder and rateless fountain codes, our system allows reliable multicast of high-quality video to an arbi- trary number of heterogeneous receivers without the requirement of feedback chan- nels. Extending this work on separate source-channel coding, we consider distributed joint source-channel coding by using a singl

关键词： Wyner-Ziv coding video Slepian-Wolf coding distributed source coding Book Thesis

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Temporal-Spatial Symmetric distributed Multi-View Video coding Scheme

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INTERNATIONAL JOURNAL OF PATTERN RECOGNITION AND ARTIFICIAL INTELLIGENCE 2017年第8期31卷 1755011-1755011页

作者： Zhang, Guoyun Xiang, Canqun Ou, Xianfeng Yue, Hong Guo, Longyuan Wu, Jianhui Tu, Bing He, Wei Hunan Inst Sci & Technol Coll Informat & Commun Engn Yueyang 414006 Peoples R China Hunan Inst Sci & Technol Key Lab Optimizat & Control Complex Syst Yueyang 414006 Peoples R China SIPO Patent Off Patent Examinat Cooperat Ctr Chengdu 610000 Sichuan Peoples R China

To improve the rate stability and make a balance for different viewpoints in distributed multi-view video coding (DMVC) system, a novel symmetric DMVC (SDMVC) scheme is proposed in this paper. In the proposed scheme, every frame from all views adopts the same encoding mode and stable output rates are achieved, which are significant to improve the transmission efficiency in the channel. Both temporal and spatial correlations are exploited, in addition, a novel side information (SI) generation algorithm aiming at better exploring the correlations of proposed scheme has been proposed to obtain better performance. The simulation results show that the proposed SDMVC scheme gets a much more stable rate than the asymmetric scheme, only with neglectable bit-rate increasing. Meanwhile, the proposed SI generation algorithm significantly improves the coding performance.

关键词： distributed source coding symmetric distributed multi-view video coding side information generation stable bit rate

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LineCast: Line-Based distributed coding and Transmission for Broadcasting Satellite Images

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2014年第3期23卷 1015-1027页

作者： Wu, Feng Peng, Xiulian Xu, Jizheng Microsoft Res Asia Beijing 100080 Peoples R China

In this paper, we propose a novel coding and transmission scheme, called LineCast, for broadcasting satellite images to a large number of receivers. The proposed LineCast matches perfectly with the line scanning cameras that are widely adopted in orbit satellites to capture high-resolution images. On the sender side, each captured line is immediately compressed by a transform-domain scalar modulo quantization. Without syndrome coding, the transmission power is directly allocated to quantized coefficients by scaling the coefficients according to their distributions. Finally, the scaled coefficients are transmitted over a dense constellation. This line-based distributed scheme features low delay, low memory cost, and low complexity. On the receiver side, our proposed line-based prediction is used to generate side information from previously decoded lines, which fully utilizes the correlation among lines. The quantized coefficients are decoded by the linear least square estimator from the received data. The image line is then reconstructed by the scalar modulo dequantization using the generated side information. Since there is neither syndrome coding nor channel coding, the proposed LineCast can make a large number of receivers reach the qualities matching their channel conditions. Our theoretical analysis shows that the proposed LineCast can achieve Shannon's optimum performance by using a high-dimensional modulo-lattice quantization. Experiments on satellite images demonstrate that it achieves up to 1.9-dB gain over the state-of-the-art 2D broadcasting scheme and a gain of more than 5 dB over JPEG 2000 with forward error correction.

关键词： Image broadcasting satellite images distributed source coding power allocation

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distributed lossless compression algorithm for hyperspectral images based on the prediction error block and multiband prediction

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OPTICAL ENGINEERING 2016年第12期55卷 123114-123114页

作者： Li, Yongjun Li, Yunsong Song, Juan Liu, Weijia Li, Jiaojiao Xidian Univ Sch Telecommun Engn State Key Lab Integrated Serv Networks 2 South Taibai StHitech Dev Zone Xian 710071 Peoples R China Xidian Univ Sch Telecommun Engn Joint Lab High Speed Multisource Image Coding & P 2 South Taibai StHitech Dev Zone Xian 710071 Peoples R China Xidian Univ Sch Software 2 South Taibai StHitech Dev Zone Xian 710071 Peoples R China

We address the problem of the lossless compression of hyperspectral images and present two efficient algorithms inspired by the distributed source coding principle, which perform the compression by means of the blocked coset coding. In order to make full use of the intraband and interband correlation, the prediction error block scheme and the multiband prediction scheme are introduced in the proposed algorithms. In the proposed algorithms, the prediction error of each 16 x 16 pixel block is partitioned into prediction error blocks of size 4 x 4. The bit rate of the pixels corresponding to the 4 x 4 prediction error block is determined by its maximum prediction error. This processing takes advantage of the local correlation to reduce the bit rate efficiently and brings the negligible increase of additional information. In addition to that, the proposed algorithms can be easily parallelized by having different 4 x 4 blocks compressed at the same time. Their performances are evaluated on AVIRIS images and compared with several existing algorithms. The experimental results on hyperspectral images show that the proposed algorithms have a competitive compression performance with existing distributed compression algorithms. Moreover, the proposed algorithms can provide low-codec complexity and high parallelism, which are suitable for onboard compression. (C) 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)

关键词： hyperspectral images lossless compression distributed source coding coset coding block

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Trends and perspectives in image and video coding

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PROCEEDINGS OF THE IEEE 2005年第1期93卷 6-17页

作者： Sikora, T Tech Univ Berlin D-10587 Berlin Germany

The objective of the paper is to provide an overview on recent trends and future perspectives in image and video coding. Here, I review and the rapid development in the field during the past 40 years and outline current state-of-the art strategies for coding images and videos. These and other coding algorithms are discussed in the context of international JPEG, JPEG 2000, MPEG-1/2/4, and H.261/3/4 standards. Novel techniques targeted at achieving higher compression gains, error robustness, and network/device adapt-ability are described and discussed.

关键词： discrete cosine transform (DCT) distributed source coding embedded coding error concealment image coding International Telecommunication Union-Telecommunications (ITU-T) Joint Photographic Experts Group (JPEG) motion compensation JPEG 2000 Motion Picture Experts Group (MPEG) standardization video coding wavelets

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Hash-Based Identification of Sparse Image Tampering

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2009年第11期18卷 2491-2504页

作者： Tagliasacchi, Marco Valenzise, Giuseppe Tubaro, Stefano Politecn Milan Dipartimento Elettron & Informat I-20133 Milan Italy

In the last decade, the increased possibility to produce, edit, and disseminate multimedia contents has not been adequately balanced by similar advances in protecting these contents from unauthorized diffusion of forged copies. When the goal is to detect whether or not a digital content has been tampered with in order to alter its semantics, the use of multimedia hashes turns out to be an effective solution to offer proof of legitimacy and to possibly identify the introduced tampering. We propose an image hashing algorithm based on compressive sensing principles, which solves both the authentication and the tampering identification problems. The original content producer generates a hash using a small bit budget by quantizing a limited number of random projections of the authentic image. The content user receives the (possibly altered) image and uses the hash to estimate the mean square error distortion between the original and the received image. In addition, if the introduced tampering is sparse in some orthonormal basis or redundant dictionary, an approximation is given in the pixel domain. We emphasize that the hash is universal, e. g., the same hash signature can be used to detect and identify different types of tampering. At the cost of additional complexity at the decoder, the proposed algorithm is robust to moderate content-preserving transformations including cropping, scaling, and rotation. In addition, in order to keep the size of the hash small, hash encoding/decoding takes advantage of distributed source codes.

关键词： Compressive sensing distributed source coding image hashing

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Geometry-Driven distributed Compression of the Plenoptic Function: Performance Bounds and Constructive Algorithms

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2009年第3期18卷 457-470页

作者： Gehrig, Nicolas Dragotti, Pier Luigi Univ London Imperial Coll Sci Technol & Med Commun & Signal Proc Grp London SW7 2AZ England Odus Technol SA CH-1800 Vevey Switzerland

In this paper, we study the sampling and the distributed compression of the data acquired by a camera sensor network. The effective design of these sampling and compression schemes requires, however, the understanding of the structure of the acquired data. To this end, we show that the a priori knowledge of the configuration of the camera sensor network can lead to an effective estimation of such structure and to the design of effective distributed compression algorithms. For idealized scenarios, we derive the fundamental performance bounds of a camera sensor network and clarify the connection between sampling and distributed compression. We then present a distributed compression algorithm that takes advantage of the structure of the data and that outperforms independent compression algorithms on real multiview images.

关键词： distributed source coding image coding sampling methods sensor networks

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Systematic Polar Codes for Joint source-Channel coding in Wireless Sensor Networks and the Internet of Things

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Procedia Computer Science 2017年 110卷 266-273页

作者： Charles Yaacoub Malak Sarkis Department of Telecommunications Faculty of Engineering Holy Spirit University of Kalsik (USEK) P.O.Box 446 Jounieh Lebanon

The Internet of Things (IoT) is becoming an increasingly growing topic of interest in the research community. Its requirements meet those of the next generation 5G mobile communication system which is expected to be an enabling technology for IoT, where networks of large numbers of sensors require massive connectivity demands. As polar codes have strongly entered into action within the standardization of 5G, this paper proposes and investigates the use of systematic polar codes for joint-source channel coding of correlated sources thus allowing, on one hand, the compression of the volume of data to be transmitted over the network, and on the other hand, the protection of this data from channel impairments. Results show that systematic polar codes can achieve a distributed compression with rates close to the theoretical bound, with better error rates obtained for larger blocks. However, stronger compression and shorter block lengths allow for a better robustness against transmission errors.

关键词： channel coding compression distributed source coding entropy internet of things systematic polar codes wireless sensor networks

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