P. J. Burt (1981) proposed, on the basis of his experiments, the HDC (hierarchical discrete correlation) method for realizing a Gaussian filter. The authors present a theoretical analysis of HDC, answer some questions...
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ISBN:
(纸本)0818606339
P. J. Burt (1981) proposed, on the basis of his experiments, the HDC (hierarchical discrete correlation) method for realizing a Gaussian filter. The authors present a theoretical analysis of HDC, answer some questions posed by Burt's experiments, and indicate the rules for the design of HDC filters.
An algorithm for finding the medial axis of an object in a 2-D binary picture has been developed. A set of real-valued boundary points for the object is extracted and smoothed using a linear combination of points in t...
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An algorithm for finding the medial axis of an object in a 2-D binary picture has been developed. A set of real-valued boundary points for the object is extracted and smoothed using a linear combination of points in the immediate neighborhood. A more detailed set of points is then defined by interpolation using a parabolic blending technique. To obtain the medial axis, circles are fitted for each point in the detailed set of points. Ech circle must be tangent to the point, be totally enclosed by the object and be of maximum size. The centers of these circles lie on the medial axis. The technique is especially suited to noisy data or coarsely sampled shapes.
A new distance measure is introduced for comparing polygonal curves which may be geometrically distorted relative to one another. The measure includes both directional and positional differences between segments and i...
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A new distance measure is introduced for comparing polygonal curves which may be geometrically distorted relative to one another. The measure includes both directional and positional differences between segments and is relatively insensitive to segmentation irregularity. Segment pairing is implemented with a conventional dynamic programming technique. Polygonal approximation allows great search reduction over pixel-based matching, thus making the technique practical for use on small computers. In addition, the measure is compatible with standard pruning techniques for even greater increases in speed. Some preliminary results in regard to handprinted character matching are shown.
A map-guided approach to interpretation of remotely sensed imagery is described, with emphasis on applications involving continuous monitoring of predetermined ground sites. Geometric correspondence between a sensed i...
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A map-guided approach to interpretation of remotely sensed imagery is described, with emphasis on applications involving continuous monitoring of predetermined ground sites. Geometric correspondence between a sensed image and a symbolic reference map is established in an initial stage of processing.by adjusting parameters of a sensor model so that image features predicted from the map optimally match corresponding features extracted from the sensed image. Information in the map is then used to constrain where to look in an image and what to look for. With such constraints, previously intractable remote sensing tasks can become feasible, even easy, to automate.
The shape of a two-dimensional contour can be conveniently transformed into an amplitude-vs-distance signal by allowing a line segment of specified length to trace out the contour and recording the angular variation o...
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The shape of a two-dimensional contour can be conveniently transformed into an amplitude-vs-distance signal by allowing a line segment of specified length to trace out the contour and recording the angular variation of the line segment as a function of distance along the contour. The line segment, which connects two points on the contour, may be of strictly fixed length or may span a fixed number of links in a chain-coded representation of the contour. The contour may be closed or open. The record of angular variation (i. e. , the incremental curvature) is independent of the orientation of the contour and can also be made independent of scale.
We present an overview of DNA microarray image requirements for automated processing.and information extraction from spotted glass slides. Motivation of our review comes from the need to automate high-throughput micro...
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We introduce a hierarchical color segmentation technique that combine the advantages of local (simplicity and quickness) and global region growing methods (robustness, accuracy, avoidance of chaining mismatches). The ...
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ISBN:
(纸本)081863880X
We introduce a hierarchical color segmentation technique that combine the advantages of local (simplicity and quickness) and global region growing methods (robustness, accuracy, avoidance of chaining mismatches). The method is implemented for a traffic sign recognition system.
The following topics are dealt with: stereovision;vision applications;segmentation and interpolation of three-dimensional surfaces;edge-finding by image filtering;hardware systems for shape;character and word recognit...
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ISBN:
(纸本)0818607211
The following topics are dealt with: stereovision;vision applications;segmentation and interpolation of three-dimensional surfaces;edge-finding by image filtering;hardware systems for shape;character and word recognition;structure from motion;multiple scales and sensor integration;image representation and processing.parallel visual algorithms;segmentation of images;industrial vision systems;textures;visual motion;image coding and processing.edge detection;and shape from texture. 110 papers were presented, all of which are published in full in the present proceedings. Abstracts of individual papers can be found under the relevant classification codes in this or other issues.
A new class of texture features based on the joint occurrences of gray levels at points defined relative to edge maxima are introduced. These features are compared with previous types of cooccurrence-based features, a...
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A new class of texture features based on the joint occurrences of gray levels at points defined relative to edge maxima are introduced. These features are compared with previous types of cooccurrence-based features, and experimental results are presented indicating that the new features should be useful for texture classification. In the second part, three simple methods of extracting texture primitives are compared. It appears that the simplest of these, thresholding at a fixed percentile, yields primitives that are quite effective in texture discrimination.
The problem of estimating the error probability of a given classification system is considered. Statistical properties of the empirical error count (C) and the average conditional error (R) estimators are studied. It ...
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The problem of estimating the error probability of a given classification system is considered. Statistical properties of the empirical error count (C) and the average conditional error (R) estimators are studied. It is shown that in the large sample case the R estimator is unbiased and its variance is less than that of the C estimator. In contrast to conventional methods of Bayes error estimation the unbiasedness of the R estimator for a given classifier can be obtained only at the price of an additional set of classified samples. On small test sets the R estimator may be subject to a pessimistic bias caused by the averaging phenomenon characterising the functioning of conditional error estimators.
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