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Coherently three-dimensional wavelet-based approach to volumetric image compression

JOURNAL OF ELECTRONIC IMAGING 1998年第3期7卷 474-485页

作者： Luo, JB Eastman Kodak Co Imaging Res & Adv Dev Rochester NY 14650 USA Univ Missouri Dept Elect Engn Columbia MO 65211 USA

Compression of three-dimensional (3D) or four-dimensional medical image data has now become imperative for clinical picture archiving and communication systems (PACS), telemedicine, and telepresence networks. While lossless compression is often desired, lossy compression techniques are gaining acceptance for medical applications, provided that clinically important information can be preserved in the coding process. We present a coherently three-dimensional method for volumetric image compression using 3D wavelet transform and 3D zerotree coding. First the volumetric image data is decomposed using 3D separable wavelet filterbanks. In this study, we adopt a three-level decomposition to form a 22-band multiresolution pyramid of an octree. Then, to exploit the dependencies among the subband coefficients resulting from 3D wavelet decomposition, a 3D zerotree coding scheme is utilized. To take advantage of the near-Laplacian distributions of the subband coefficients and the efficiency of zerotree coding, a pseudouniform quantization is adopted. The proposed volumetric image compression scheme is applied to two sets of real CT medical data. Significant coding gains have been achieved which demonstrate the effectiveness of the proposed volumetric image compression scheme for medical as well as other applications. (C) 1998 SPIE and IS&T. [S1017-9909(98)02703-2].

关键词： Image compression 3D image processing Quantization Wavelets Image filtering Wavelet transforms algorithm development Lithium Medical imaging Reconstruction algorithms

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Check image compression using a layered coding method

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JOURNAL OF ELECTRONIC IMAGING 1998年第3期7卷 426-442页

作者： Huang, JC Wang, Y Wong, EK Polytech Univ Dept Elect Engn Brooklyn NY 11201 USA Polytech Univ Dept Comp & Informat Sci Brooklyn NY 11201 USA

An emerging trend in the banking industry is to digitize checks for storage and transmission. An immediate requirement for efficient storage and transmission is check image compression. General purpose compression algorithms such as JPEG and wavelet-based methods produce annoying ringing or blocking artifacts at high compression ratios, in this paper, a layered approach to check image compression is proposed in which a check image is represented in several layers. The first layer describes the foreground map;the second layer specifies the gray levels of foreground pixels;the third layer is a lossy representation of the background image;and the fourth layer describes the error between the original and the reconstructed image of the first three layers. The layered coding approach produces images of better quality than traditional JPEG and wavelet coding methods, especially in the foreground, i.e., the text and graphics, in addition, this approach allows progressive retrieval or transmission of different image layers. (C) 1998 SPIE and IS&T. [S1017-9909(98)01403-2].

关键词： Image compression Image segmentation Image quality Chromium Visualization Binary data Image processing algorithms and systems Image processing algorithm development Wavelets

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Application-specific image compression for multimedia applications

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JOURNAL OF ELECTRONIC IMAGING 1998年第3期7卷 464-473页

作者： Moni, S Cadence Design Syst Sunnyvale CA 94086 USA USN Air Warfare Ctr Weap Div China Lake CA 93555 USA

In order to establish a synergy between the compression scheme and the intended processing of the compressed image, we develop a family of compression algorithms that can adapt to the specialized requirements imposed by the application. The focus of this work is on wavelet-based compression for still images. A family of eight compression schemes is proposed to address specialized multimedia requirements such as (i) partial evaluation of wavelet coefficients, (ii) asymptotic losslessness of the algorithms, (iii) tree-structure in the selected coefficients, and (iv) optimization of either energy compaction or coefficient retention. Experimental results, including fraction of coefficients evaluated, rate-distortion performance, and coefficient retention are presented. (C) 1998 SPIE and IS&T. [S1017-9909(98)00503-0].

关键词： Image compression Computer programming Wavelets Multimedia Quantization Databases algorithm development Visualization Image processing Telemedicine

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Block-matching algorithm based on dynamic adjustment of search window for low bit-rate video coding

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JOURNAL OF ELECTRONIC IMAGING 1998年第3期7卷 571-577页

作者： Oh, HS Lee, HK Korea Adv Inst Sci & Technol Dept Comp Sci Taejon 305701 South Korea

A dynamic search window adjustment for block-matching algorithm (BMA) based on the block similarity is presented to reduce the computational complexity of full search BMA. The adjustment of the size of the search window is performed in three steps: (1) set a new search origin based on the block similarity and the displaced block difference (DBD), (2) adjust the size of search window in inverse proportion to block similarity, and (3) update the thresholds for accommodation to a given image sequence. The technique can be easily applied to full search BMA and several fast search algorithms to get more efficiency and to reduce a possibility of falling into a local minimum. Experimental results show that the proposed technique has a good MSE performance and reduces the number of search points substantially. (C) 1998 SPIE and IS&T. [S1017-9909(98)02303-4].

关键词： Video Image segmentation Video coding Image processing algorithms and systems Distortion algorithm development Motion estimation Computer science Computer simulations

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Near-lossless image compression techniques

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JOURNAL OF ELECTRONIC IMAGING 1998年第3期7卷 486-494页

作者： Ansari, R Memon, N Ceran, E Univ Illinois Dept EECS MC 154 Chicago IL 60607 USA No Illinois Univ Dept Comp Sci De Kalb IL 60115 USA

Predictive and multiresolution techniques for near-lossless image compression based on the criterion of maximum allowable deviation of pixel values are investigated. A procedure for near-lossless compression using a modification of lossless predictive coding techniques to satisfy the specified tolerance is described. Simulation results with modified versions of two of the best lossless predictive coding techniques known, CALIC and JPEG-LS, are provided. Application of lossless coding based on reversible transforms in conjunction with prequantization is shown to be inferior to predictive techniques for near-lossless compression. A partial embedding two-layer scheme is proposed in which an embedded multiresolution coder generates a lossy base layer, and a simple but effective context-based lossless coder codes the difference between the original image and the lossy reconstruction. Results show that this lossy plus near-lossless technique yields compression ratios close to those obtained with predictive techniques, while providing the feature of a partially embedded bit-stream. (C) 1998 SPIE and IS&T. [S1017-9909(98)00203-7].

关键词： Image compression Transform theory Quantization Computer programming Image processing Tolerancing algorithm development Information visualization Medical imaging Visualization

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Perceptual image similarity experiments 3

Perceptual image similarity experiments

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Conference on Human Vision & Electronic Imaging

作者： Rogowitz, BE Frese, T Smith, JR Bouman, CA Kalin, E IBM Corp Thomas J Watson Res Ctr Yorktown Heights NY 10598 USA

ISBN: (纸本)081942739X

In this paper, we study how human observers judge image similarity. To do so, we have conducted two psychophysical scaling experiments and have compared the results to two algorithmic image similarity metrics. For these experiments, we selected a set of 97 digitized photographic images which represent a range of semantic categories, viewing distances, and colors. We then used the two perceptual and the two algorithmic methods to measure the similarity of each image to every other image in the data set, producing four similarity matrices. These matrices were analyzed using multidimensional scaling techniques to gain insight into the dimensions human observers use for judging image similarity, and how these dimensions differ from the results of algorithmic methods. This paper also describes and validates a new technique for collecting similarity judgments which can provide meaningful results with a factor of four fewer judgments, as compared with the paired comparisons method.

关键词： Matrices 3D image processing Image processing Ions Photography Visual process modeling Visualization algorithm development Monte Carlo methods Image retrieval

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Stochastic gradient estimation strategies for Markov random fields

Stochastic gradient estimation strategies for Markov random ...

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Conference on Bayesian Inference for Inverse Problems

作者： Younes, L ENS Cachan CMLA F-94235 Cachan France

ISBN: (纸本)0819429147

This communication presents new results about convergence of stochastic gradient algorithms for maximum likelihood estimation of Markov random fields. We first present theoretical results dealing with the convergence of a generalized Robbins-Monro procedure. These results provide rigorous justifications for simple numerical strategies which can be employed in practice;they are illustrated by numerical experiments.

关键词： Stochastic processes algorithms Statistical analysis Data modeling algorithm development Explosives Computer simulations Image analysis Internet Statistical modeling

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Planning of collision free paths for holonic Blastman robots

Planning of collision free paths for holonic Blastman robots

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Conference on Intelligent Robots and Computer Vision XVII - algorithms, Techniques, and Active Vision

作者： Rintala, M Heikkila, T Blastman Robot Ltd FIN-90101 Oulu Finland

ISBN: (纸本)081942983X

Collision freeness is an essential feature in off-line programming of robots. It relates to safe and efficient operation, and becomes even more critical, when two or more robots are sharing the same work space, which is typical for so called holonic robot systems. Here we are reporting a simple and fast path planning algorithm based on configuration space method, suitable for holonic robot applications. The basic version of the algorithm can be found from the literature, and we have extended and modified it to improve its feasibility. Simulation and experimental tests have been carried out succesfully.

关键词： Robots Space robots Telescopes Robotic systems Space telescopes algorithm development Manufacturing Computer programming Free space Robotics

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Scientific capabilities of SIFTER for discovering and monitoring gamma-ray bursts and active galactic nuclei

Scientific capabilities of SIFTER for discovering and monito...

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Conference on Hard X-Ray and Gamma-Ray Detector Physics and Applications

作者： Pendleton, GN Kippen, RM Mallozzi, RS Richardson, GA Buckley, J Israel, MH Rielage, K Fishman, GJ Parnell, TA Christl, MJ Wilson, RB Koshut, T Univ Alabama Huntsville AL 35899 USA

ISBN: (纸本)0819429015

An exciting possibility for the GLAST main instrument is a scintillating fiber system where the properties of both a tracker and a calorimeter are combined in one type of detector module. This instrument provides all the detector capabilities required to achieve the science goals of the GLAST mission, at a substantially reduced cost compared to the baseline technology, and with the benefit of increased effective area and superior low energy angular resolution.

关键词： Sensors Particles Detection and tracking algorithms Spatial resolution algorithm development Electrons Reconstruction algorithms Gamma radiation Monte Carlo methods Space operations

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Gray scale optical correlator 9

Gray scale optical correlator

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Conference on Optical Pattern Recognition IX

作者： Chao, TH Reyes, G Park, YC CALTECH Jet Prop Lab Ctr Space Microelect Technol Pasadena CA 91109 USA

ISBN: (纸本)0819428353

A compact (Camcorder size), ultrahigh-speed, grayscale optical correlator capable of using grayscale input and real-valued correlation filter is reported. The unique bipolar-amplitude correlation filter modulation capability has enabled the direct implementation of composite filter algorithm such as MACH [8]. The direct usage of grayscale input also eliminated the need of image preprocessing (e.g. Sober filtering used for binary optical correlator). System architecture of this grayscale optical correlator will be described. Experimental results obtained using optically implemented MACH filter, for the first time, will also be provided.

关键词： Optical correlators Spatial light modulators Optical filters Image filtering Distortion Modulation Target detection LCDs algorithm development Composites

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