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Conference on visual communications and image processing 2004

作者： Tang, XL Pearlman, WA Rensselaer Polytech Inst ECSE Dept Troy NY 12180 USA

ISBN: (纸本)0819452114

We investigate and compare the performance of several three-dimensional (3D) embedded wavelet algorithms on lossless 3D image compression. The algorithms are Asymmetric Tree Three-Dimensional Set Partitioning In Hierarchical Trees (AT-3DSPIHT), Three-Dimensional Set Partitioned Embedded bloCK (3D-SPECK), Three-Dimensional Context-Based Embedded Zerotrees of Wavelet coefficients (3D-CB-EZW), and JPEG2000 Part II for multi-component images. Two kinds of images are investigated in our study -8-bit CT and MR medical images and 16-bit AVIRIS hyperspectral images. First, the performances by using different size of coding units are compared. It shows that increasing the size of coding unit improves the performance somewhat. Second, the performances by using different integer wavelet transforms are compared for AT-3DSPIHT, 3D-SPECK and 3D-CB-EZW. None of the considered filters always performs the best for all data sets and algorithms. At last, we compare the different lossless compression algorithms by applying integer wavelet transform on the entire image volumes. For 8-bit medical image volumes, AT-3DSPIHT performs the best almost all the time, achieving average of 12% decreases in file size compared with JPEG2000 multi-component, the second performer. For 16-bit hyperspectral images, AT-3DSPIHT always performs the best, yielding average 5.8% and 8.9% decreases in file size compared with 3D-SPECK and JPEG2000 multi-component, respectively. Two 2D compression algorithms, JPEG2000 and UNIX zip, are also included for reference, and all 3D algorithms perform much better than 2D algorithms.

关键词： medical imaging hyperspectral imaging lossless image compression EZW SPIHT JPEG2000

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Power-rate-distortion analysis for wireless video communication under energy constraint

Power-rate-distortion analysis for wireless video communicat...

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Conference on visual communications and image processing 2004

作者： He, ZH Liang, YF Ahmad, I Univ Missouri Dept Elect & Comp Engn Columbia MO 65211 USA

ISBN: (纸本)0819452114

In video coding and streaming over wireless communication network, the power-demanding video encoding operates on the mobile devices with limited energy supply. To analyze, control, and optimize the rate-distortion (R-D) behavior of the wireless video communication system under the energy constraint, we need to develop a power-rate-distortion (P-R-D) analysis framework, which extends the traditional R-D analysis by including another dimension, the power consumption. Specifically, in this paper, we analyze the encoding mechanism of typical video encoding systems and develop a parametric video encoding architecture which is fully scalable in computational complexity. Using dynamic voltage scaling (DVS), a hardware technology recently developed in CMOS circuits design, the complexity scalability can be translated into the power consumption scalability of the video encoder. We investigate the rate-distortion behaviors of the complexity control parameters and establish an analytic framework to explore the P-R-D behavior of the video encoding system. Both theoretically and experimentally, we show that, using this P-R-D model, the encoding system is able to automatically adjust its complexity control parameters to match the available energy supply of the mobile device while maximizing the picture quality. The P-R-D model provides a theoretical guideline for system design and performance optimization in wireless video communication under energy constraint, especially over the wireless video sensor network.

关键词： Video Video coding Computer programming Control systems Motion estimation Distortion Wireless communications Telecommunications Mobile devices Video surveillance

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Temporal layered vs. multi-state video coding

Temporal layered vs. multi-state video coding

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Conference on visual communications and image processing 2004

作者： Ekmekci, S Sikora, T Tech Univ Berlin Berlin Germany

ISBN: (纸本)0819452114

Multiple Description Video Coding (MDC) and Layered Coding (LC) are both error-resilient source coding techniques used for transmission over error-prone channels. Both techniques generate multiple streams. The streams generated by MDC correspond to different descriptions of the same source whereas the streams produced by LC are differentiated as base and enhancement layer streams. Moreover whereas the MDC streams are independently decodable the decoding of the enhancement layer stream is dependent on the decoding of the base layer stream. In this work we concentrate on specific MDC and LC schemes, i.e. Multi-State Video Coding (MSVC) and Temporal Layered Coding (TLC). MSVC was introduced in(1) and it was showed that if each frame is transmitted in a separate packet and if motion information for each lost frame is also lost, MSVC outperforms Single Layer Coding (SC) in recovering from single as well as burst losses. Here we compared MSVC with TLC as an extension of SC based on transmission simulations over lossy channels under the assumption that the motion vectors are always available. Using different coding modes and specific reconstruction methods average reconstructed frame PSNR (peak signal to noise ratio) is measured and compared. Results show that when motion vectors are received TLC performs better than MSVC for every coding option tested. The performance difference is bigger for low motion sequences.

关键词： layered coding multi-state video coding multiple description coding error-resilient video communications rate allocation Automatic Repeat reQuest (ARQ) error concealment

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Perceptual masks in the wavelet domain for color image watermarking 12

Perceptual masks in the wavelet domain for color image water...

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12th European Signal processing Conference, EUSIPCO 2004

作者： Sayrol, Elisa Martínez, Elena Department of Signal Theory and Communications Universitat Politècnica de Catalunya Campus Nord UPC - Mòdul D5 Jordi-Girona 1-3 Barcelona08034 Spain

ISBN: (纸本)9783200001657

In this paper, three different perceptual masks in the wavelet domain are investigated for image watermarking systems. Along with an already existing method, we present two alternative perceptual masks based on visual detection thresholds in Y, Cb and Cr color channels and on the JPEG2000 significance coding step. A procedure to compare the perceptual masks consists on evaluating on one side, the PSNR and the S-CIELAB visual quality measure and on the other side, the detection performance by a blind watermarking scheme. Experimental results proof the better performance of the two alternative masks as well as the insights that can be derived from the comparison approach. © 2004 EUSIPCO.

关键词： image watermarking

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Distributed compression of the plenoptic function

Distributed compression of the plenoptic function

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2004 International Conference on image processing, ICIP 2004

作者： Gehrig, Nicolas Dragotti, Pier Luigi Communications and Signal Processing Group Electrical and Electronic Engineering Department Imperial College Exhibition Road London SW7 2AZ United Kingdom

ISBN: (纸本)0780385543

In this paper, we consider the problem of distributed compression in camera sensor networks. Due to the spatial proximity of the different cameras, acquired images can be highly dependent. The correlation in the visual information retrieved is related to the structure of the plenoptic function and can be estimated using geometrical information such as the position of the cameras and some bounds on the location of the objects. We propose a distributed compression scheme that takes advantage of this geometrical information in order to reduce the over-all transmission rate from the sensors to a common central receiver. This new approach allows for a flexible repartition of the transmission bit-rates amongst the encoders and is optimal in many cases. Moreover, we show that our coding scheme can be made resilient to a fixed number of occlusions and that perfect reconstruction and interpolation are possible at the receiver. ©2004 IEEE.

关键词： image compression

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Dissolve detection for archive films

Dissolve detection for archive films

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Proceedings of the IEEE 12th Signal processing and communications Applications Conference, SIU 2004

作者： Güllü, M. Kemal Urhan, Oǧuzhan Ertürk, Sarp Kocaeli Üniversitesi Elektronik ve Haberleşme Mühendisliǧi Bölümü 41040 Izmit Kocaeli

ISBN: (纸本)0780383184

This paper proposes a novel pixel based method for the detection of dissolves in archive films. Initially video frames are sub-sampled in order to reduce effects caused by zoom and visual degradations encountered in the video. Object and camera movement effects are reduced using an excessive change mask that rules out pixels that display extreme variations. Ascending, descending and constant pixel characteristics are tracked within a period of thirty frames and the local peaks of a metric constructed using these characteristics are utilized for dissolve detection. ©2004 IEEE.

关键词： image processing

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Perceptual quality metrics: Evaluation of individual components

Perceptual quality metrics: Evaluation of individual compone...

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2004 International Conference on image processing, ICIP 2004

作者： Fontaine, B. Saadane, A. Thomas, A. Institut de Recherche en Communications et Cybernétique de Nantes Ecole Polytechnique Université de Nantes rue Christian Pauc 44300 Nantes France

Based on the numerous quality metrics proposed in the literature, an evaluation of the individual visual model components have been performed. Effort has been focused on the perceptual decomposition and spatial pooling. Four perceptual decompositions have been considered. Three of them include both radial and orientation selectivity while for the fourth one, only a radial decomposition is performed. Five spatial pooling models have been associated to each of these decompositions. The first model is the most used one and consists in a simple Minkowski summation. In the second one, the Minkowski summation is weighted by the occurrence probability of the perceived errors contrast. The last three models are new and include higher level perceptual processes. © 2004 IEEE.

关键词： image quality

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visual communications with side information via distributed printing channels: extended multimedia and security perspectives

Visual communications with side information via distributed ...

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6th Conference on Watermarking of Multimedia Contents

作者： Voloshynovskiy, S Koval, O Deguillaume, F Pun, T Univ Geneva CUI CH-1211 Geneva 4 Switzerland

ISBN: (纸本)0819452092

In this paper we address visual communications via printing channels from an information-theoretic point of view as communications with side information. The solution to this problem addresses important aspects of multimedia data processing, security and management, since printed documents are still the most common form of visual information representation. Two practical approaches to side information communications for printed documents are analyzed in the paper. The first approach represents a layered joint source-channel coding for printed documents. This approach is based on a self-embedding concept where information is first encoded assuming a Wyner-Ziv set-up and then embedded into the original data using a Gel'fand-Pinsker construction and taking into account properties of printing channels. The second approach is based on Wyner-Ziv and Berger-Flynn-Gray set-ups and assumes two separated communications channels where an appropriate distributed coding should be elaborated. The first printing channel is considered to be a direct visual channel for images ("analog" channel with degradations). The second "digital channel" with constrained capacity is considered to be an appropriate auxiliary channel. We demonstrate both theoretically and practically how one can benefit from this sort of "distributed paper communications".

关键词： data-hiding printed documents communications with side information bar-codes distributed coding joint source-channel coding Gel'fand-Pinsker problem Wyner-Ziv coding Berger-Flynn-Gray coding image enhancement authentication integrity control

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Distributed source coding of multiview images

Distributed source coding of multiview images

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Conference on visual communications and image processing 2004

作者： Tehrani, MP Fujii, T Tanimoto, M Nagoya Univ Dept Informat Elect Grad Sch Engn Chikusa Ku Nagoya Aichi 4648603 Japan

ISBN: (纸本)0819452114

Considering nodes energy and channel bandwidth limitations in a multiview images network, avoiding inter-node communication in the coding scheme is necessary and makes the communication efficient, in comparison with conventional coding methods with internode communication. In our system, we consider a multiview images network as an array of nodes on a line with the same distance to each other. Each node in this system includes a camera to capture with a limited processing and communication abilities. We propose a multiview images coding without requiring inter-node communication, to gain the advantage of correlation at decoder side for two network configurations, but the main concept of the proposed coding for both network configurations is the same. The two network configurations are distinguished based on presence of parent node in each cluster, which sends full information to central node (i.e. joint decoder). The other nodes called children nodes and send their partial information to central node. In this paper, a coding scheme is proposed for multiview images network with parent node based on the number of parent nodes (i.e. "one parent node cluster" and "two parent node cluster") in each cluster. Not that, because we are involved with multiview images, the decoding procedure is searching for correspondence between partially sent multiview images data. In coding scheme with parent node, if each parent node fails the decoding task of children nodes will be failed or the error caused by corresponding search during the decoding of children nodes is increased if network uses other parent nodes to decode the cluster without parent node. To make the network robust in case of node failure, we avoid parent nodes, and developed a network configuration where all nodes are children nodes (i.e. "without parent node cluster"). For such a network, we also propose a coding algorithm for multiview images that the joint decoder at central node is able to decode the partial info

关键词： distributed source coding multiview image corresponding search ray-space interpolation children node parent node network with parent node and network without parent node

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Video coding with H.264/AVC: Tools, performance, and complexity

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IEEE Circuits and Systems Magazine 2004年第1期4卷 7-28页

作者： Ostermann, Jörn Bormans, Jan List, Peter Marpe, Detlev Narroschke, Matthias Pereira, Fernando Stockhammer, Thomas Wedi, Thomas Inst. Theor. Nachrichtentech./I. University of Hannover Hannover Germany IMEC Leuven Belgium Deutsche Telecom T-Systems Darmstadt Germany Fraunhofer-Inst. for Telecom. Heinrich Hertz Institute Berlin Germany Inst. Theor. Nachrichtentech./I. University of Hannover Appelstr. 9a 30167 Hannover Germany Instituto Superior Técnico Inst. de Telecom. Lisbaa Portugal Inst. for Communications Engineering Munich University of Technology Germany

H.264/AVC, the result of the collaboration between the ISO/IEC Moving Picture Experts Group and the ITU-T Video Coding Experts Group, is the latest standard for video coding. The goals of this standardization effort were enhanced compression efficiency, network friendly video representation for interactive (video telephony) and non-interactive applications (broadcast, streaming, storage, video on demand). H.264/AVC provides gains in compression efficiency of up to 50% over a wide range of bit rates and video resolutions compared to previous standards. Compared to previous standards, the decoder complexity is about four times that of MPEG-2 and two times that of MPEG-4 visual Simple Profile. This paper provides an overview of the new tools, features and complexity of H.264/AVC.

关键词： image coding

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