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2014 IEEE 5th International Conference on Software Engineering and Service Science

作者： Zhi Chen Chenhao Mu Fan Xu Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences

embedded zero-tree wavelet(EZW) is a kind of image compression algorithm which provides high compression rates *** order to improve the quality of reconstructed image after decoding,in this research,we put forward an improvement of embedded zerotree wavelet coding and simulate this new *** method takes full advantages of the Compressed Sensing(CS) theory and *** results demonstrated that the proposed method improved the quality of the unzipped image significantly.

关键词： Image compression Wavelet Zero-tree Compressed Sensing embedded coding

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Bit-stream allocation methods for scalable video coding supporting wireless communications

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2007年第3期22卷 298-316页

作者： Zgaljic, Toni Sprljan, Nikola Izquierdo, Ebroul Univ London Queen Mary Dept Elect Engn Multimedia & Vis Grp London England

The demand for video access services through wireless networks, as important parts of larger heterogeneous networks, is constantly increasing. To cope with this demand, flexible compression technology to enable optimum coding performance, especially at low bit-rates, is required. In this context, scalable video coding emerges as the most promising technology. A critical problem in wavelet-based scalable video coding is bit-stream allocation at any bit-rate and in particular when low bit-rates are targeted. In this paper two methods for bit-stream allocation based on the concept of fractional bit-planes are reported. The first method assumes that minimum rate-distortion (R-D) slope of the same fractional bit-plane within the same bit-plane across different subbands is higher than or equal to the maximum R-D slope of the next fractional bit-plane. This method is characterised by a very low complexity since no distortion evaluation is required. Contrasting this approach, in the second method the distortion caused by quantisation of the wavelet coefficients is considered. Here, a simple yet effective statistical distortion model that is used for estimation of R-D slopes for each fractional bit-plane is derived. Three different strategies are derived from this method. In the first one it is assumed that the used wavelet is nearly orthogonal, i.e. the distortion in the transform domain is treated as being equivalent to the distortion in the signal domain. To reduce the error caused by direct distortion evaluation in the wavelet domain, the weighting factors are applied to the used statistical distortion model in the second strategy. In the last strategy, the derived statistical model is used during the bit-plane encoding to determine optimal position of the fractional bit-plane corresponding to refinement information in the compressed bit-stream. Results of selected experiments measuring peak signal to noise ratio (PSNR) of decoded video at various bit-rates are reported.

关键词： bit-plane coding embedded coding fractional bit-plane ordering low bit-rate coding post-compression rate-distortion optimization scalable video coding

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Rate control for an embedded wavelet video coder

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 1997年第4期7卷 696-702页

作者： Cheng, PY Li, J Kuo, CCJ SHARP LABS AMER DIGITAL VIDEO DIV CAMAS WA 98607 USA UNIV SO CALIF INTEGRATED MEDIA SYST CTR LOS ANGELES CA 90089 USA UNIV SO CALIF DEPT ELECT ENGN SYST LOS ANGELES CA 90089 USA

embedded coders provide a better rate-distortion tradeoff while the coded bit stream can be truncated at any point without a significant perceptible distortion. In this work, we investigate rate control for an embedded wavelet video coder bg converting the rate control problem to a bit allocation problem for each frame. Then, a computationally efficient rate control algorithm is derived by exploiting the rate distortion performance of the embedded wavelet coder and the frame dependency between the reference frame and the predictive frame, Experiments are performed to demonstrate the superior performance of the embedded wavelet video coder with the proposed rate control scheme. It is shown that the proposed rate control strategy outperforms the fixed allocation rate control by 0.1-0.4 dB for a variety of sequences, and the performance gain can be as large as 1.3-2.7 dB around scene changes.

关键词： embedded coding MPEG multimedia rate control video coding video compression wavelet transform

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Matching pursuit-based region-of-interest image coding

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2007年第2期16卷 406-415页

作者： Ebrahimi-Moghadam, Abbas Shirani, Shahram McMaster Univ Dept Elect & Comp Engn Hamilton ON L8S 4K1 Canada

Matching pursuit (MP) is a multiresolution signal analysis method and can be used to render a selected region of an image with a specific quality. A novel, scalable, and progressive MP-based region-of-interest image-coding scheme is presented. The method is capable of providing a trade off between rate, distortion, and complexity. The method also provides an interactive way of information refinement for regions of an image with higher receiver's priority. By selecting a proper subset of the huge initial MP dictionary, using the method described in this paper, the complexity burden of MP analysis can be adapted to the computational power of the image encoder.

关键词： embedded coding image compression lossy compression matching pursuit (MP) region-of-interest (ROI) scalability

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High performance scalable image compression with EBCOT

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2000年第7期9卷 1158-1170页

作者： Taubman, D Univ New S Wales Sch Elect Engn Sydney NSW Australia

A new image compression algorithm is proposed, based on independent embedded Block coding with Optimized Truncation of the embedded bit-streams (EBCOT), The algorithm exhibits state-of-the-art compression performance while producing a bit-stream with a rich set of features, including resolution and SNR scalability together with a "random access" property, The algorithm has modest complexity and is suitable for applications involving remote browsing of large compressed images. The algorithm lends itself to explicit optimization with respect to MSE as well as more realistic psychovisual metrics, capable of modeling the spatially varying visual masking phenomenon.

关键词： embedded coding image compression JPEG 2000 random access rate-distortion optimization scalabitity visual masking

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Wavelet coding of volumetric medical datasets

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IEEE TRANSACTIONS ON MEDICAL IMAGING 2003年第3期22卷 441-458页

作者： Schelkens, P Munteanu, A Barbarien, J Galca, M Giro-Nieto, X Cornelis, J Fund Sci Res Flanders FWO B-1000 Brussels Belgium Free Univ Brussels Dept Elect & Informat Proc ETRO B-1050 Brussels Belgium

Several techniques based on the three-dimensional (3-D) discrete cosine, transform, (DCT) have been proposed for volumetric data coding. These techniques fail to provide lossless coding coupled with quality and resolution scalability, which is a significant drawback for medical applications. This paper gives an overview, of several state-of-the-art 3-D, wavelet coders that do meet these requirements and proposes new compression methods exploiting the quadtree and block-based coding concepts;layered zero-coding principles, and context-based arithmetic coding. Additionally, a new 3-D DCT-based coding scheme is designed and used for benchmarking. The proposed wavelet-based coding algorithms produce embedded data streams that can be decoded up to the lossless level and support the desired set of functionality constraints. Moreover, objective and subjective quality evaluation on various medical volumetric datasets shows that the proposed algorithms provide competitive lossy and lossless compression results when compared with the state-of-the-art.

关键词： embedded coding JPEG2000 layered zero coding lossless compression medical image compression progressive image transmission quadtree coding volumetric coding

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OPTIMAL-CONTROL OF VARIABLE-RATE coding IN INTEGRATED VOICE DATA PACKET NETWORKS

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PERFORMANCE EVALUATION 1989年第2期10卷 115-128页

作者： SAITO, H NIPPON TELEGRAPH & TEL PUBL CORP MUSASHINO ELECT COMMUN LAB COMMUN SWITCHING LABS MUSASHINO TOKYO 180 JAPAN

The problem of controling dynamic voice coding rate to reduce traffic congestion in an integrated voice/data packet network is investigated. The embedded coding scheme is considered and the design of a control is formulated as an optimization problem with a constraint. It is shown that the control which achieves the maximum average voice packet coding rate under an average queue length (or an average waiting time) constraint has a simple structure specified by two parameters and is a randomized modification of two feedback controls with input saturation.

关键词： Integrated Voice/Data Packet Networks Flow Control Variable Rate coding embedded coding Lagrange Multiplier Markovian Decision Process

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Efficient transmission of compressed data for remote volume visualization

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IEEE TRANSACTIONS ON MEDICAL IMAGING 2006年第9期25卷 1189-1199页

作者： Krishnan, Karthik Marcellin, Michael W. Bilgin, Ali Nadar, Mariappan S. Univ Arizona Dept Elect & Comp Engn Signal Proc & Coding Lab Tucson AZ 85721 USA Univ Arizona Dept Radiol Tucson AZ 85721 USA Siemens Corp Res Princeton NJ 08540 USA

One of the goals of telemedicine is to enable remote visualization and browsing of medical volumes. There is a need to employ scalable compression schemes and efficient client-server models to obtain interactivity and an enhanced viewing experience. First, we present a scheme that uses JPEG2000 and JPIP (JPEG2000 Interactive Protocol) to transmit data in a multi-resolution and progressive fashion. The server exploits the spatial locality offered by the wavelet transform and packet indexing information to transmit, in so far as possible, compressed volume data relevant to the clients query. Once the client identifies its volume of interest (VOI), the volume is refined progressively within the VOI from an initial lossy to a final lossless representation. Contextual background information can also be made available having quality fading away from the VOI. Second, we present a prioritization that enables the client to progressively visualize scene content from a compressed file. In our specific example, the client is able to make requests to progressively receive data corresponding to any tissue type. The server is now capable of reordering the same compressed data file on the fly to serve data packets prioritized as per the client's request. Lastly, we describe the effect of compression parameters on compression ratio, decoding times and interactivity. We also present suggestions for optimizing JPEG2000 for remote volume visualization and volume browsing applications. The resulting system is ideally suited for client-server applications with the server maintaining the compressed volume data, to be browsed by a client with a low bandwidth constraint.

关键词： code-block discrete wavelet transform (DWT) embedded coding JPEG2000 JPIP precinct scalable compression

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Decoupled 3-D zerotree structure for wavelet-based video coding

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IEEE TRANSACTIONS ON BROADCASTING 2008年第3期54卷 430-436页

作者： Zhang, Liang Wang, Demin Vincent, Andre Commun Res Ctr Ottawa ON K2H 8S2 Canada

A novel data structure is proposed for magnitude-ordering 3-D wavelet transform coefficients. This data structure consists of temporal I-D orientation trees followed by spatial 2-D orientation trees. Based on this data structure, a coding algorithm is developed for the embedded coding of 3-D wavelet transform coefficients. Experiment results confirm that the proposed coding algorithm outperforms a conventional algorithm that uses asymmetric 3-D orientation trees.

关键词： embedded coding set partitioning in hierarchical trees (SPIHT) video coding wavelet transform

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Optimal packetization scheme for embedded multimedia bitstreams using genetic algorithms

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INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY 2006年第3期16卷 77-84页

作者： Wei, Jianming Salari, Ezzatollah Univ Toledo Dept Elect Engn & Comp Sci Toledo OH 43606 USA

The problem of packetizing embedded multimedia bit-streams into fixed-size packets is investigated and an optimal packetization scheme using a genetic algorithm is presented. In the proposed method, each individual packetization instance is represented by a decision sequence and mapped to a chromosome. A steady-state genetic algorithm is applied to search for the optimal chromosome that minimizes the distortion between the original and the reconstructed media. In addition, we propose a fast method to calculate the fitness value based on the distortion associated with each chromosome to speed up the evolution process. The computer simulation results show that our proposed packetization scheme has high compression efficiency and provides error resiliency to packet losses with a relatively fast speed. (C) 2006 Wiley Periodicals, Inc.

关键词： image compression genetic algorithms packetization wavelet transform embedded coding

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