A description is given of a versatile imageprocessing system developed at Pratt & Whitney Aircraft (P&WA) and the highly efficient spatial domain filtering techniques which are its computational heart. By exp...
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A description is given of a versatile imageprocessing system developed at Pratt & Whitney Aircraft (P&WA) and the highly efficient spatial domain filtering techniques which are its computational heart. By exploiting block average filtering techniques requiring only local storage, each block filtering operation uses only four additions and one multiplication per pixel, regardless of image or block size. As a consequence, extremely rapid imageprocessing is possible;for example, deconvolution of a 512 multiplied by 512 pixel image can be performed in just five seconds on an IBM 3033 with Fortran code.
The widely used stepwise discriminant analysis procedure selects one variable at a time. However, instances arise in which variables occur naturally paired, such as the real and imaginary parts of a Fourier transforme...
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The widely used stepwise discriminant analysis procedure selects one variable at a time. However, instances arise in which variables occur naturally paired, such as the real and imaginary parts of a Fourier transformed signal. The existing stepwise discriminant procedure might select the real part of the ith harmonic and the imaginary part of the jth harmonic. This paper presents an algorithm that selects variables in pairs. With this algorithm, both the phase and magnitude of a signal can be used to form a discriminant function, as compared to the existing method of using the power only. From the simulation study, the discriminant procedure is better for inherently paired variables.
The nearest-neighbor and potential function decision rules are nonparametric techniques that partition the feature space based on a set of labelled sample points. Determining whether the partitions of the two rules ar...
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The nearest-neighbor and potential function decision rules are nonparametric techniques that partition the feature space based on a set of labelled sample points. Determining whether the partitions of the two rules are identical for a given set of points is an interesting problem in computational geometry. A relationship between the two methods in terms of subclasses and composite classes is developed. Considering an exponential potential function, necessary and sufficient conditions for identity of their decision surfaces are obtained. Based on conditions of symmetry, weighting, and the Voronoi region of a point, an algorithm for establishing identity in R**d is introduced.
There is presented the software implementation of a new type of region grower for object boundary finding when the boundaries are highly variable and the images very noisy. The approach is both structural and probabil...
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There is presented the software implementation of a new type of region grower for object boundary finding when the boundaries are highly variable and the images very noisy. The approach is both structural and probabilistic and consists of data modeling followed by boundary finding through statistical estimation realized as cost functional minimization. The algorithm, involving a first guess at the boundary followed by successively improving approximations, is described, and also described is its implementation and experimental results.
Because of the increasing demand for cytogenetic analysis, machine assisted karyotyping of human chromosomes is almost a necessity. One of the most important phases in chromosome analysis and other related histo- or c...
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Because of the increasing demand for cytogenetic analysis, machine assisted karyotyping of human chromosomes is almost a necessity. One of the most important phases in chromosome analysis and other related histo- or cytochemistry work is the scanning of microscopic slides to detect suitable metaphases or cells. In this paper such a system is described based on the use of microprocessors, a digitally controlled microscope, and video hardware for autofocus, thresholding and feature extraction. A hierarchically structured search procedure has excellent results at a scanning speed of 0. 5 cm**2/min.
A new type of two-dimensional formal grammars known as 'Multilevel Array Grammars' (MLAG) is introduced. This is based on the extention of concepts used in Array Grammars as defined by Milgram and Rosenfeld. I...
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A new type of two-dimensional formal grammars known as 'Multilevel Array Grammars' (MLAG) is introduced. This is based on the extention of concepts used in Array Grammars as defined by Milgram and Rosenfeld. In these grammars, the 'terminal symbols' of a grammar defined at a higher level ( greater than 0) are themselves patterns of a specified shape, which, in turn, are derived from the grammars defined at lower level. These 'terminal symbols' can be viewed as 'floor tiles' which are laid according to the rewriting rules in generating a two-dimensional texture scene. These grammars are shown to be adequate to generate texture scenes that can be viewed at many levels, such as ″brick wall type″ textures.
The three-dimensional shape analysis problem is a very demanding test of shape analysis algorithms. Previous approaches to the problem have employed global features such as moments and Fourier descriptors. Global feat...
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The three-dimensional shape analysis problem is a very demanding test of shape analysis algorithms. Previous approaches to the problem have employed global features such as moments and Fourier descriptors. Global features lack the capacity for solving the partial shape recognition problem, in which only part of the unknown shape is available. Previous approaches to local shape analysis have employed structural (syntactic) methods, but these methods have so far failed to solve the three-dimensional problem. This study describes a hybrid structural/statistical local shape analysis algorithm which is applied to the three-dimensional problem.
A hardware array processor designed principally for imageprocessing applications, called BASE 8, has been developed. BASE 8 has the appearance of a fully parallel Binary Array processor to the programmer, however it ...
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A hardware array processor designed principally for imageprocessing applications, called BASE 8, has been developed. BASE 8 has the appearance of a fully parallel Binary Array processor to the programmer, however it processes a large array in a sequence of 8 multiplied by 8 blocks. A BASE 8 processor is designed to be connected to and controlled by a minicomputer such as a PDP 11. It greatly enhances the performance of the host computer for some imageprocessing algorithms and also provides a flexible hardware model for Binary Array processor architecture research. The hardware organization of BASE 8 is described and its performance for some imageprocessing algorithms is given.
recognition of three dimensional objects independent of size, position and orientation is an important and difficult problem of scene analysis. The use of three dimensional moment invariants is proposed as a solution....
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recognition of three dimensional objects independent of size, position and orientation is an important and difficult problem of scene analysis. The use of three dimensional moment invariants is proposed as a solution. The generalization of the results of two dimensional moment invariants which had linked two dimensional moment invariants to binary quantics is done by linking three dimensional moments to ternary quantics. The existence and number of n**t**h order moments in two and three dimensions is explored. Algebraic invariants of several ternary forms under different orthogonal transformations are derived by using the invariant property of the coefficients of ternary forms. The result is a set of three dimensional moment invariants which are invariant under size, orientation and position change.
The development of algorithms for real-time, automatic systems capable of tracking 2-D targets in complex scenes is discussed. The problems and constraints involved in such an undertaking as well as previous efforts a...
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The development of algorithms for real-time, automatic systems capable of tracking 2-D targets in complex scenes is discussed. The problems and constraints involved in such an undertaking as well as previous efforts are summarized. In addition, a mathematical model of scene spatial and teral evolution is developed for certain classes of targets and target perturbations. It is shown that for small target perturbations the 2-D tracking problem may be approximated as a 1-D time-varying parameter estimation problem. Algorithms resulting from several estimation approaches are discussed.
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