The authors describe applications and give evaluations of rule-based methods for image analysis. They used rule-based programming methods for two image-analysis applications: segmenting and interpreting images of prin...
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ISBN:
(纸本)0818608625
The authors describe applications and give evaluations of rule-based methods for image analysis. They used rule-based programming methods for two image-analysis applications: segmenting and interpreting images of printed circuit boards, and segmenting satellite images of ice floes. Such problems are often divided into low-, mid-, and high-level processing, and they consider rule-based, or declarative, programming at the mid and high levels. They used KnowledgeTool, an OPS-like language that allows an excellent mix of procedural and declarative code. This ability to mix procedural and declarative code was very useful, but the authors nevertheless found limitations using the rule-based programming model. They describe these and list characteristics of image problems in which declarative coding can be applied.
The application of gray-scale digitizers to the digitization of binary images of straight-edged silhouettes is considered. A measure of digitization-induced ambiguity is introduced. It is shown that if the gray levels...
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ISBN:
(纸本)0818608625
The application of gray-scale digitizers to the digitization of binary images of straight-edged silhouettes is considered. A measure of digitization-induced ambiguity is introduced. It is shown that if the gray levels are not quantized and the sampling resolution is sufficiently high, error-free reconstruction of the original binary image from the digitized image is possible. When the total bit-count for the representation of the digitized image is limited, i.e., sampling resolution and quantization accuracy are both finite, error-free reconstruction is usually impossible. The authors' suggested bit allocation policy is then to increase the quantization accuracy as much as possible, once sufficient sampling resolution has been reached.
A novel approach to machine-based visual perception of monocular images is described and initial recognition results are presented. The approach uses a recursive procedure to generate a series of reconstructed version...
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ISBN:
(纸本)0818608625
A novel approach to machine-based visual perception of monocular images is described and initial recognition results are presented. The approach uses a recursive procedure to generate a series of reconstructed versions of the raw video image. The procedure is motivated by certain perceptual organization functions of the human visual system. recognition of object categories is attempted at each step by comparing the newly generated regions to stored object categories. These generated regions may have relatively few edges or region pixels in common with any of the regions in the raw video image. Category retrieval is carried out using a software-based content-addressing scheme which provides access to complete object representations in memory using incomplete portions of the representation. The category-representation scheme is sufficiently general to allow a variety of poorly correlated images of specific category examples to be represented and recognized by a single general category representation. These properties are illustrated using a group of distorted, defective, and idealized images of ASCII A's and handguns.
A parallel algorithm for detecting dominant points on a digital closed curve is presented. The procedure requires no input parameter and remains reliable even when features of multiple sizes are present on the digital...
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ISBN:
(纸本)0818608625
A parallel algorithm for detecting dominant points on a digital closed curve is presented. The procedure requires no input parameter and remains reliable even when features of multiple sizes are present on the digital curve. The procedure first determines the region of support for each point based on its local properties, then computes measures of relative significance (e.g., curvature) of each point, and finally detects dominant points by a process of nonmaxima suppression. This procedure leads to an important observation that the performance of dominant points detection depends not only on the accuracy of the measure of significance, but mainly precise determination of the region of support. This solves the fundamental problem of scale factor selection encountered in various dominant point detection algorithms. The inherent nature of scale-space filtering in the procedure is addressed and the performance of the procedure is compared to those of several other dominant point-detection algorithms, using a number of examples.
The authors present a method which reduces an n-point problem to a set of four-point problems. The effort of reduction takes O(n) steps and it also takes O(n) steps to construct all possible mappings of an n-point set...
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ISBN:
(纸本)0818608625
The authors present a method which reduces an n-point problem to a set of four-point problems. The effort of reduction takes O(n) steps and it also takes O(n) steps to construct all possible mappings of an n-point set from the solution to a four-problem. Other results include (1) coplanarity condition of four points in two views, (2) recovering the tilt direction of the rotational axis using four points in two views, and (3) recovering the scaling factor.
A recursive cluster detection technique is described for segmenting the color pictures. The proposed method operates in the (L*, a *, b*)-uniform color space and detects image clusters by fitting them some circular-cy...
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ISBN:
(纸本)0818608625
A recursive cluster detection technique is described for segmenting the color pictures. The proposed method operates in the (L*, a *, b*)-uniform color space and detects image clusters by fitting them some circular-cylindrical decision volumes. This estimates the clusters' distributions in the uniform color space without imposing any constraints on their forms. Boundaries of the decision elements consist of two planes of constant lightness, two cylinders of constant chroma, and two planes of constant hue. They are determined using 1-D histograms of the L*, H0, C* cylindrical coordinates of the space. The detected clusters are then correctly isolated from their neighbors by projecting their estimated color distributions onto the Fisher linear discriminant function for 1-D thresholding.
Shadows provide information that allows inferences to be made about the three-dimensional nature of objects. Essential to those inferences is the ability to identify segments of the shadow boundary that correspond to ...
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ISBN:
(纸本)0818608625
Shadows provide information that allows inferences to be made about the three-dimensional nature of objects. Essential to those inferences is the ability to identify segments of the shadow boundary that correspond to various portions of the object that has cast the shadow. Entry-exit vertices, that are extremes of the boundary, and tangent to the projection of the light beams, can be identified as junctions of specific segments of the shadow boundary. The authors restrict the analysis to smooth convex bodies, and prove that points of discontinuity of the derivative on the shadow boundary form another set of vertices. These two types of junctions are discussed extensively, and combined into a labeling scheme that can segment the boundary into logically consistent pieces. They include a series of experimental results that depicts the process of labeling as well as the final labeling itself. The authors discuss the possible ambiguities that may arise during the labeling process due to occlusion of one object by another, and show that there is no ambiguity in the cases of occlusion of shadows and of shadows that fall on other objects.
The authors describe a connectionist network which is not a neural net in which knowledge is distributed globally via the connections of functionally simple nodes. The technique combines constraint propagation with an...
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ISBN:
(纸本)0818608625
The authors describe a connectionist network which is not a neural net in which knowledge is distributed globally via the connections of functionally simple nodes. The technique combines constraint propagation with analogical or eidetic representations. It represents an alternative to the atomistic signals-to-symbols paradigm in which a one-to-one correspondence is assumed to exist between symbols and the concepts they represent.
The authors consider imagecomputations on a mesh with reconfigurable bus (reconfigurable mesh). The architecture consists of an array of processors overlaid with a reconfigurable bus system. The reconfiguration schem...
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ISBN:
(纸本)0818608625
The authors consider imagecomputations on a mesh with reconfigurable bus (reconfigurable mesh). The architecture consists of an array of processors overlaid with a reconfigurable bus system. The reconfiguration scheme can be used to dynamically obtain various interconnection patterns among the processor elements. The reconfiguration scheme supports several parallel techniques developed on the CRCW PRAM (concurrent read, concurrent write parallel random-access machine) model, leading to asymptotically superior solution times to image problems compared to those on the mesh with multiple broadcasting, the mesh with multiple buses, the mesh-of-trees, and the pyramid computer.
Novel techniques are described for model-based recognition of 3-D objects from unknown viewpoints using single-gray-scale images. The objects in the scene may be overlapping and partially occluded. Efficient matching ...
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ISBN:
(纸本)0818608625
Novel techniques are described for model-based recognition of 3-D objects from unknown viewpoints using single-gray-scale images. The objects in the scene may be overlapping and partially occluded. Efficient matching algorithms, which assume affine approximation to the perspective viewing transformation, are proposed. The study is currently restricted to flat rigid 3-D objects. Point, line and curve matching algorithms are presented. The study especially emphasizes the curve matching problem. Experimental results are included.
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