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Performance of the H.263 Video Compression Standard

Journal of VLSI Signal processing Systems for Signal, image, and Video Technology 1997年第2-3期17卷 101-111页

作者： Girod, Bernd Steinbach, Eckehard Färber, Nikolaus Telecommunications Institute University of Erlangen-Nuremberg 91058 Erlangen Cauerstrasse 7 Germany Georgia Institute of Technology United States University of Hannover Germany Inst. F. Theor. N. University of Hannover Germany Massachussetts Inst. of Technology Cambridge MA United States Research Laboratory of Electronics United States Department of Media Technology Media Laboratory Germany Department of Computer Graphics Germany Academy of Media Arts Cologne Germany Computer Science Section Cologne University Germany Digital Signal Processing Group Georgia Institute of Technology Atlanta GA United States Dept. of Elec. Eng./Telecom. University of Erlangen-Nuremberg Germany Telecommunications Institute Germany Vivo Software Inc. Waltham MA United States University of Karlsruhe Germany University of Essex United Kingdom ESIEE Paris France Image Communication Group Telecommunications Institute University of Erlangen-Nuremberg Germany University of Munich Germany Telecommunications Institute University of Erlangen-Nuremberg Germany Image Communication Group

The draft international standard ITU-T H.263 is closely related to the well known and widely used ITU-T Recommendation H.261. However, H.263 does provide the same subjective image quality at less than half the bit-rate. In this paper we investigate to what extend single enhancements of H.263 contribute to this performance gain, and consider the trade-off quality vs. complexity. Based on typical test sequences, H.263 with its various modes is compared to H.261 on the basis of rate distortion curves at bit-rates up to 128 kbps. At 64 kbps, the performance gain of H.263 in its default mode compared to H.261 is approximately 2 dB. This improvement is achieved with only little increase of complexity, and is mainly due to more accurate motion compensation with half-pel accuracy. Considering the trade-off quality vs. complexity, the combination of the optional coding-modes "Advanced prediction mode" and "PB-frames mode" is a good compromise, resulting in an additional performance gain of 1.5 dB PSNR at 64 kbps. The "Syntax-based arithmetic coding mode" on the other hand, offers only a very small performance gain (0.1 dB at 64 kbps) for its increased computational complexity. Results from profiling an H.263 software codec are presented in order to support complexity considerations of the optional coding-modes.

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Automated matching experiments with different kinds of SAR imagery

Automated matching experiments with different kinds of SAR i...

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IEEE International Symposium on Geoscience and Remote Sensing (IGARSS)

作者： M. Gelautz G. Jakob G. Paar S. Hensley F. Leberl Institute for Computer Graphics Technical University of Graz Graz Austria JOANNEUM RESEARCH Institute of Digital Image Processing Graz Austria Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA

The authors carry out tests with two readily available automated matching algorithms in their application to (a) Magellan SAR stereo images, and (b) ERS-1 and X-SAR real-simulated images. The match points are examined... 详细信息

关键词： Testing Computational modeling Pixel image matching Radar imaging Speckle Shape measurement computer graphics Drives Digital images

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Adaptability of K-L expansion technique for ambiguous face image retrieval

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1996年第10期79卷 35-46页

作者： Oda, M Akamatsu, S Fukamachi, H ATR Human Information Processing Laboratories Kyoto Japan 619-02 Shigeru Akamatsu received his B.E. M.E. and Dr. of Eng. degrees in Mathematical Enginwring and Instrumentation Physics in 1975 1977 and 1994 respectively from the University of Tokyo Japan. In 1977 he joined the Electrical Communications Laboratories Nippon Telegraph and Telephone Public Corporation Yokosuka Japan. From 1977 through 1985 he was engaged in the research and development of optical character recognition systems for handwritten Chmese characters. During the academic year 1985-86 he was a Visiting Researcher at the University of California Irvine California U.S.A. Until 1992 he was a Senior Research Engineer Supervisor at W Human Interface Laboratories and conducted research on human image recognition with a special interest in face recognition. Since 1992 he has been with ATR Human Information Processing Research Laboratories Kyoto Japan where he is currently Head of Department 2. His research interests include computational and cognitive studies on high-level vision with a special interest in facial information processing by man and computer. He is a member of the Institute of Electronics Information and Communication Engineers of Japan the Information Processing Society of Japan ACM and the IEEE Computer Society. Hidm Fukamachi received his B.E. degree in Image Technology from the Tokyo Institute of Polytechnics in 1990. He joined NTT Software Corp. in 1990 where he was engaged in the development of image processing software. Since 1993 he has been with ATR Human Information Processing Research Laboratories.

Some facial images are not necessarily clear images in the human brain. However, it can be easily judged whether a face matches the image in our mind;this is true even when the drawing or the expression of the target image is difficult to comprehend. This is because even if the image cannot be imagined like a picture, it does exist. The authors have proposed a system with which a retriever can retrieve an ambiguous target image from an image database. The system's retrieval efficiency and ease-of-retrieval were clarified by experiments using line drawn facial images. In this paper, the system is extended to photographs of faces. The most difficult problem in treating photographs is determining the retrieval key. One consideration is to add the subjective impressions or features of physical figures as keywords for each image data. Regardless of the method, however, significant manpower is necessary. The K-L expansion technique is used here, which has been verified as effective for face identification, and expect to need only a small amount of manpower. This paper investigates whether the technique can also be useful in ambiguous image retrieval.

关键词： ambiguous image image retrieval K-L expansion facial image subjective similarity

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Heterogeneous morphing of multimodal medical information 6th

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6th International Conference on computer Analysis of images and Patterns, CAIP 1995

作者： Jankovič, Vojtech Ružický, Eugen Gröller, Eduard Department of Computer Graphics and Image Processing Comenius University Bratislava842 15 Slovakia Department of Visualization and Animation Institute of Computer Graphics Technical University Vienna Austria

ISBN: (纸本)3540602682

The paper presents a general non-rigid body representation for physically-based modeling of dynamic behaviour of heterogeneous objects and its application in a development of a new heterogeneous morphing technique to solve distortion correction problems arising in the medical data processing. The proposed representation provides a simply applicable tool for modeling of real medical objects allowing fast and reliable calculation of geometric deformations and simulation of dynamic behaviour in a heterogeneous environment when only a few initial landmark displacements are known. The proposed method is applied in a distortion correction process of CT medical data sets, especially in an automatic processing of heterogeneous CT scans of human brain. © Springer-Verlag Berlin Heidelberg 1995.

关键词： computerized tomography

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INCREASING THE FEATURE SIZE IN HANDWRITTEN NUMERAL RECOGNITION TO IMPROVE ACCURACY

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SYSTEMS AND computerS IN JAPAN 1995年第8期26卷 35-44页

作者： WAKABAYASHI, T TSURUOKA, S KIMURA, F MIYAKE, Y Member Faculty of Engineering Mie University Tsu Japan 514 Furnitaka Kimura:received his B.E. and Ph.D. degrees in 1973 and 1978 respectively from Nagoya University where he was appointed a Research Associate the same year. He has been an Associate Professor at Mie University since 1983. He had been a Visiting Associate Professor at the University of Michigan Dearborn from 1989 to 1991. He has engaged in research on pattern recognition image processing computer graphics. He is a member of Institute of Information Processing Japan Institute of Medical Engineering Japan and Institute of Artificial Intelligence Japan. Members Yasuji Miyab:received his B.E. and Ph.D. degrees in 1957 and 1965 respectively from Nagoya University where he was appointed a Research Associate in 1965. He was appointed to a Lecturer in 1968 and an Associate Professor in 1969. He has been a Professor at Mie University since 1978. He has engaged in research on machine recognition of handwritten characters computer graphics and medical image processing. He is a member of Institute of Information Processing Japan Institute of Artificial Intelligence Japan Institute of Robotics Japan I.E.E.E. Japan and Institute of Simulation Japan.

The relationship between the recognition rate of handwritten numerals and the normality of the distribution of their features has been investigated experimentally with a large amount of data in various combinations of quantized orientations and regions. The recognition method is based on the histogram of local orientation of contours of each numeral. To obtain a more accurate orientation quantization, the effectiveness of the orientation quantization using the gray-scale gradient has also been investigated. The results show that: (1) to increase the dimensionality of features, it is better to increase the number of quantized orientations, keeping the number of regions small (e.g., 4 x 4 or 5 x 5);(2) in the same dimensionality, the better the normality of a feature distribution, the higher the recognition rate;(3) a quantization of orientations using gray scales is effective for normalizing a feature distribution;and (4) the filter processing in reduction of the number of quantization scales improves the normality and recognition rate. The recognition of handwritten numerals collected from actual posts were carried out by using the gray-scale local-orientation histogram (400 dimensions). A correct recognition rate of 99.18 percent (mean value) has been obtained.

关键词： CHARACTER RECOGNITION PATTERN RECOGNITION ZIP CODE RECOGNITION FEATURE EXTRACTION GRADIENT NORMALITY

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Development and application of MCAL tools for marine radar instruction

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computer Applications in Engineering Education 1995年第4期3卷 259-259页

作者： Guirguis, S. Korany, E. Abdel-Bary, A. Institute of Graduate Studies and Research Alexandria University Alexandria Egypt Shawkat K. Guirguis:obtained the BSc and M.Sc. degrees in Computer Science and Automatic Control Faculty of Engineering Alexandria University in 1981 and 1984 respectively. In 1988 he obtained a PhD degree in Electronics and Communications Faculty of Engineering Cairo University co-supervised by the Imperial College of Science and Technology University of London where he spent two years as an academic visitor. His current research interests include software quality management multimedia automatic programming and decision support systems. He is currently a lecturer of Computer Science at the Institute of Graduate Studies & Research Alexandria University. Ezzat A. Korany:received the BS degree in Electrical Engineering (Electronics Section) from the University of Alexandria Egypt in 1971 the MS degree in Electrical Engineering (Computer Section) from Ain Shams University Cairo Egypt in 1977 and the PhD degree in Electrical Engineering (Digital Systems) from Florida Institute of Technology U.S.A. in 1982. He is currently an associate professor of Computer Science at the Institute of Graduate Studies & Research University of Alexandria. His research interests are in data communications and multimedia applications computer networks image processing and pattern recognition. Abdel-Latif A. Abdel-Bary:obtained the BEng degree in Electronics Technology from Arab Maritime Transport Academy in 1986. In 1995 he obtained the MSc degree in Information Technology from the Institute of Graduate Studies & Research Alexandria University. His current research interests include ICAL hypermedia and automatic programming.

In this article a multimedia computer-assisted learning (MCAL) system is presented. The major objective of this work was to investigate the potential of using such systems as tools for transferring instructional course information through various types of computer media as opposed to the classic CAL systems. The philosophy and techniques employed to design the system are investigated. Usage of the implemented system and its merits have been illustrated through its application to teach engineering students and technicians the theory and concepts of marine radar. System design, implementation, test, and revision phases are presented and discussed.

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image IDENTIFICATION AND RESTORATION IN THE SUBBAND DOMAIN (VOL 3, PG 312, 1994)

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IEEE TRANSACTIONS ON image processing 1994年第6期3卷 873-873页

作者： KIM, JM Center for Image Processing Research and Electrical Computer and Systems Engineering Department Rensselaer Polytechnic Institute Troy NY USA

When faced with a large support point spread function (PSF), the iterative expectation-maximization (EM) algorithm, which is often used for PSF identification, is very sensitive to the initial PSF estimate. To deal with this problem, the authors propose to do EM image identification and restoration in the subband domain. After the image is first divided into subbands, the EM algorithm is applied to each subband separately. Since the PSF can be taken to have smaller support in each subband, these subbands should be less of a problem with the EM model identification. They also introduce an adaptive subband EM method for use in the upper frequency subbands.

关键词： restoration bearing point subband Subbands expectation-maximisation algorithm Point spread function image recognition

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Windows computer laboratory as a tutorial for undergraduate electromagnetics

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computer Applications in Engineering Education 1995年第3期3卷 183-183页

作者： McCulloch, J. Keddy, W.A. Stuchly, M.A. University of Victoria Department of Electrical and Computer Engineering University of Victoria Victoria British Columbia Canada Janet McCulloch:is a native of Toronto Canada where she briefly attended both York University and the University of Toronto before she set off on a year-long adventure through the Middle East and North Africa. When she returned to Canada she relocated to California. She spent a number of years living both in Los Angeles and coastal Northern California interspersed with several extended trips through the United States Mexico and Central America. Ms. McCulloch moved to Victoria British Columbia in 1989 and a year later registered in the cooperative education program in Electrical Engineering at the University of Victoria. She is presently in the fifth and final year of the program and has her sights set on graduate school. Besides the work described in this article she has been very much involved in the use of technology to assist in the delivery of curriculum at the senior secondary level. She lives on a country property a half-hour from the University with her husband her horse and three cats. W. Alfred Keddy:is an applications programmer/analyst for the Department of Electrical and Computer Engineering at the University of Victoria. He received a BEng (1988) in Electrical Engineering and an MASc (1994) from the University of Victoria. His research interests include distributed systems image processing local area networks VLSI and DSP system design for computation and communication and human–computer interface design. Maria A. Stuchly:received an MSc in Electrical Engineering in 1962 from Warsaw Technical University and a PhD in Electrical Engineering from the Polish Academy of Sciences in 1970. Between the years of 1962 and 1970 she was with the Warsaw Technical University an Institute of the Polish Academy of Sciences. After immigrating to Canada during 1970 her first position was with the University of Manitoba. In 1976 she became employed by the Bureau of Radi

Contents and implementation of a computer laboratory for undergraduate electromagnetics are described. The laboratory consists of four 3-hour sessions covering vector calculus, Maxwell's equations (integral and differential forms), wave propagation in materials, and wave behavior at planar interfaces. Each session contains theory (in the Help file), animations (where relevant) and a quiz. The program runs on IBM compatible 486-based PCs in a Windows environment and uses the Borland C ++ 4.0 compiler.

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The DOMUS project - Building an OODB GIS for environmental control

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International Workshop on Advanced research in Geographic Information Systems, IGIS 1994

作者： Medeiros, Claudia Bauzer Casanova, Marco Antonio Camara, Gilberto Department of Computer Science – UNICAMP CampinasSP Brazil Rio Scientific Center IBM Brasil Rio de JaneiroRJ Brazil Image Processing Division National Institute for Space Research – INPE Sao Jose dos CamposSP Brazil

ISBN: (纸本)9783540587958

DOMUS is a project of the computer Science Department of UNICAMP, Brazil, for the development of a GIS for environmental control applications using an object oriented database. This project involves experts from different areas, both in computer Science and in Geosciences. This paper describes the results already obtained in this project, as well as the ongoing efforts to extend available GtS technology, through use of the SPRING GIS. © 1994, Springer Verlag. All rights reserved.

关键词： Environmental management

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Region-based coding of images using a spline model

Region-based coding of images using a spline model

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IEEE International Conference on image processing

作者： R. Baseri J.W. Modestino Electrical Computer and Systems Engineering Department Center for Image Processing Research Rensselaer Polytechnic Institute Troy NY USA

This paper describes a second-generation region-based coding scheme operating in a subband environment. Specifically, this is a compression technique based on approximating the lowest-frequency subband of an image with a 2-D spline model. Following a segmentation procedure, parametric polynomials are fitted to the resulting regions of the lowest-frequency subband. This subband is then represented by the spline coefficients, the region boundary description and the residual error. The residual error plus the higher-frequency subbands are encoded using conventional pixel-based quantization schemes while we describe an efficient encoding scheme for the 2-D spline representation. An entropy-constrained design procedure is developed for designing these individual encoders to minimize the overall mean-square distortion subject to a constraint on the output entropy. A comprehensive study of the operational rate-distortion performance of the resulting scheme is presented, which indicates the superiority of this approach to the more traditional pixel-based entropy-constrained schemes.< >

关键词： image coding Spline Polynomials Pixel image segmentation Systems engineering and theory image processing Quantization Entropy Contracts

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