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Digital Image processing Applications 1989

作者： Sullivan, James R. Commercial and Information Systems Research Laboratory Eastman Kodak Company RochesterNY14653-5719 United States

High speed image compression algorithms that achieve visually lossless quality at low bit-rates are essential elements of many digital imaging systems. In examples such as remote sensing, there is often the additional requirement that the compression hardware be compact and consume minimal power. To meet these requirements a new adaptive differential pulse code modulation (ADPCM) algorithm was developed that significantly reduces edge errors by including quantizers that adapt to the local bias of the differential signal. In addition, to reduce the average bit-rate in certain applications a variable rate version of the algorithm called run adaptive differential coding (RADC) was developed that combines run-length and predictive coding and a variable number of levels in each quantizer to produce bit-rates comparable with adaptive discrete cosine transform (ADCT) at a visually lossless level of image quality.∗1 It will also be shown that this algorithm is relatively insensitive to fixed-pattern sensor noise and errors in sensor correction, making it possible to perform pixel correction on the decompressed image. © 1989 SPIE.

关键词： Remote sensing

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Multiresolution techniques for image representation, analysis, and 'smart' transmission

Multiresolution techniques for image representation, analysi...

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visual Communications and Image processing IV

作者： Burt, Peter J. David Sarnoff Research Cent Princeton United States

ISBN: (纸本)0819402389

Important new techniques for representing and analyzing image data at multiple resolutions have been developed over the past several years. Closely related multiresolution structures and procedures have been developed more or less independently in diverse scientific fields. For example, pyramid and subband representations have been applied to image compression, and promise excellent performance and flexibility. Similar pyramid structures have been developed as models for the neural coding of images within the human visual system. The pyramid has been developed in the computer vision field as a general framework for implementing highly efficient algorithms, including algorithms for motion analysis and object recognition. In this paper I review these multiresolution techniques and discuss how they may be usefully combined in the future. Methods used in image compression, for example, should match the requirements of human perception, and future 'smart' transmission systems will need to perform rapid analysis in order to selectively encode the most critical information in a scene.

关键词： Image processing

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Asymptotic analysis of the total least squares ESPRIT algorithm

Asymptotic analysis of the total least squares ESPRIT algori...

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Advanced algorithms and Architectures for Signal processing IV 1989

作者： Ottersten, B. viberg, M. Kailath, T. Information Systems Laboratory Stanford University StanfordCA94305 United States Department of Electrical Engineering Linköping University LinköpingS-581 83 Sweden

This paper considers the problem of estimating the parameters of multiple narrowband signals arriving at an array of sensors. Modern approaches to this problem often involve costly procedures for calculating the estimates. The ESPRIT (Estimation of Signal Parameters via Rotational Invariance Techniques) algorithm was recently proposed as a means for obtaining accurate estimates without requiring a costly search of the parameter space. This method utilizes an array invariance to arrive at a computationally efficient multidimensional estimation procedure. Herein, the asymptotic distribution of the estimation error is derived for the Total Least Squares (TLS) version of ESPRIT. The Cramér-Rao Bound (CRB) for the ESPRIT problem formulation is also derived and found to coincide with the variance of the asymptotic distribution through numerical examples. The method is also compared to least squares ESPRIT and MUSIC as well as to the CRB for a calibrated array. Simulations indicate that the theoretic expressions can be used to accurately predict the performance of the algorithm. © 1989 SPIE. All rights reserved.

关键词： Least squares approximations

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Measuring soft tissue contour information

Measuring soft tissue contour information

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Medical Imaging III: Image Formation 1989

作者： Dunn, Stanley M. Department of Biomedical Engineering Rutgers University P.O. Box 909 PiscatawayNJ08855-0909 United States Diagnostics Systems Program New Jersey Dental School NewarkNJ United States

An inexpensive computer imaging system is being developed which is capable of accurately recovering the threedimensional surface of the human body. This system uses biologically safe structured white light. In structured light, a uniform square grid pattern is projected onto the skin and an image of this pattern is recorded using a single camera. The squares in the camera image appear distorted due to the curvature of the skin. By locating the intersections of the grid stripes and matching them correctly to the projected grid pattern, the three-dimensional positions of points on the skin surface can be determined by triangulation. Triangulation is the method by which an illuminated point on the object surface may be located in space as the intersection of two lines: the illuminating ray from the projector and the line of sight determined by the location of the point in the camera image. This system has been applied to measure facial swelling and the surface area of burns. This paper summarizes the steps in processing an image to reconstruct a surface patch of a portion of the skin. We discuss the geometry of the imaging system and show how three-dimensional information can be recovered. Next, we describe the actual processing steps and algorithms used to locate the data used to reconstruct the patch. A unique feature of the system is the compensation for the reflectance of the skin. Experiments are discussed figures are presented illustrating the various processing steps. These preliminary results demonstrate the feasibility of the imaging system in accurately reconstructing a surface patch of the skin. Finally, we summarize the present state of our project and discuss work in progress and future plans. © 1989 SPIE. All rights reserved.

关键词： Triangulation

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Suboptimal subspace-fitting methods for multidimensional signal parameter estimation

Suboptimal subspace-fitting methods for multidimensional sig...

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Advanced algorithms and Architectures for Signal processing IV 1989

作者： Swindlehurst, A.L. Roy, R. Kailath, T. Information Systems Laboratory Stanford University StanfordCA94305 United States

ESPRIT is a recently introduced algorithm for direction-of-arrival (DOA) and spectral estimation. Its principal advantage is that parameter estimates are obtained directly, without knowledge (and hence storage) of the parameter manifold and without computation or search of some spectral measure. This advantage is achieved by exploiting a certain invariance structure for the spatial or temporal signal samples;for example, in DOA estimation, it is assumed that the sensor array is composed of two identical subarrays separated by a known displacement vector. In many applications, arrays are constructed with invariances in more than one spatial direction. These arrays are typically sampled uniformly, so an additional invariance in time may also be present. In this paper, it is shown how to generalize the geometric concepts of ESPRIT to accommodate arrays with multidimensional invariance structure, and consequently to simultaneously estimate multiple parameters (e.g., azimuth, elevation, frequency, etc.) per source. The framework for this generalization is provided by the fact that ESPRIT is equivalent to a least-squares (LS) fit of the single invariance structure to a set of vectors which span the signal subspace (hence the term subspace-fitting). For ESPRIT, the TLS fit requires no constraints. In the multidimensional case, however, constraints must be applied in order to obtain an "optimal" solution. We will primarily be concerned with suboptimal methods which approximate the optimal solution. Suboptimal here refers to the fact that the constraints are satisfied by a two-stage procedure rather than simultaneously with the LS fit;i.e., an unconstrained fit is performed first, after which the solutions are "projected" in some sense back onto the constraints. © 1989 SPIE. All rights reserved.

关键词： Spectrum analysis

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Communications issues in data engineering: 'have bandwidth-will move data'

Communications issues in data engineering: 'have bandwidth-w...

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International Conference on Data Engineering

作者： O. Frieder Network Systems Research Division Bell Communications Research Inc. Morristown NJ USA

It is argued that those areas of data engineering research which are based on the assumption that communication bandwidth is a constraint, should be investigated. Some additional distributed database issues that require reinvestigation include concurrency control, network partitioning, backup storage and recovery algorithms. With the availability of increased bandwidth, global flooding of information can result in lower processing times than conventional approaches. Hence, broadcast-based solutions which continuously inform the various sites of the system status and data modifications need to be reconsidered. Novel transmission rates also invalidate old assumptions.< >

关键词： Data engineering Bandwidth Multiprocessing systems optical fibers Biomedical imaging Displays Delay Parallel processing Protocols Engines

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PERFORMANCE DATA AND LIMITING CONDITIONS OF OBJECT TRACKING algorithms IN THE PRESENCE OF CAMERA NOISE

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IEE PROCEEDINGS-F RADAR AND SIGNAL processing 1988年第1期135卷 111-113页

作者： SIEBERT, H ENGELHARDT, W System Control & Simulation Department MBB Dynamics Division Messerschmitt-Bölkow-Blohm GmbH Möunchen West Germany

The lower performance limits of two different object tracking algorithms relative to the camera noise, quantisation of the image signal, object size and contrast between object and back ground were determined using st... 详细信息

关键词： noise performance limits Television and video equipment, systems and applications video signals correlators image signal Codes quantisation statistical methods optical information, image and video signal processing analogue-digital conversion tracking television camera object tracking algorithms limiting conditions picture processing camera noise

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PROCESSOR SYSTEM FOR REALTIME viDEO SIGNAL-processing

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IEE PROCEEDINGS-E COMPUTERS AND DIGITAL TECHNIQUES 1988年第3期135卷 181-187页

作者： LIEBSCH, W ZIER, D Heinrich-Hertz Institut Berlin West Germany

A 10 ns programmable signal processor system for realtime applications in video signal and image processing has been developed and realised. Up to six instructions can be processed in one operation cycle of 10 ns. The high data throughput is attained by pipeline-structure and parallel circuit design. Several program realisations using this processor system have demonstrated that realtime processing of broadband signals with such different algorithms as edgeextractions, two-dimensional DPCM and movingpattern generation are possible in a programmable processor.

关键词： image processing pipeline-structure video signals moving-pattern generation optical information, image and video signal processing programmable signal processor two-dimensional DPCM 10 ns processor systems real-time systems parallel circuit design program realisations computerised picture processing Computer vision and image processing techniques realtime video signal processing

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Concurrent algorithms for a mobile robot vision system

Concurrent algorithms for a mobile robot vision system

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Applications of Artificial Intelligence vi 1988

作者： Jones, Judson P. Mann, Reinhold C. Engineering Physics and Mathematics Division Oak Ridge National Laboratory Oak RidgeTN37831-6364 United States

The application of computer vision to mobile robots has generally been hampered by insufficient on-board computing power. The advent of VLSI-based general purpose concurrent multiprocessor systems promises to give mobile robots an increasing amount of on-board computing capability, and to allow computation intensive data analysis to be performed without high-bandwidth communication with a remote system.

关键词： Image processing Hough transforms Computing systems Evolutionary algorithms Telecommunications Image filtering Artificial intelligence Mobile robots Navigation systems Binary data

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An experimental system for the integration of information from stereo and multiple shape from texture algorithms

An experimental system for the integration of information fr...

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Intelligent Robots and Computer vision vi 1987

作者： Boult, Terrance E. Moerdler, Mark Columbia University Department of Computer Science New York CityNY10027 United States

In numerous computer vision applications, there is both the need and the ability to access multiple types of information about the three dimensional aspects of objects or surfaces. When this information comes from different sources the combination becomes non-trivial. This paper describes the present state of ongoing research in Columbia's vision Laboratory in the integration of multiple visual sensing methodologies which yield three dimensional information, in particular, feature based stereo algorithms, and various shape-from-texture algorithms are already in operation and multi-view shape-from-texture and shape-from shading modules are expected to be incorporated. Unlike most systems for multi-sensor integration, which fuse all the information at one conceptual level, e.g., the surface level, the system under development uses two levels of data fusion, intra-process integration and inter-process integration. The paper discusses intra-process integration techniques for feature-based stereo and shape-from-texture algorithms. It also discusses a inter-process integration technique based on smooth models of surfaces. Examples are presented using camera acquired images. © 1988 SPIE. All rights reserved.

关键词： Stereo image processing

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