To determine the in-plane strain components from the 3-D displacement vector data of a loaded object, its shape has to be known. The phase shifting speckle interferometric system, described in this paper, has been use...
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ISBN:
(纸本)0819406813
To determine the in-plane strain components from the 3-D displacement vector data of a loaded object, its shape has to be known. The phase shifting speckle interferometric system, described in this paper, has been used for both the displacement vector measurements and for the acquisition of the essential shape information. The numerical shape data resulting from the application of a phase shifting technique allows further calculations, e.g. the determination of the object surface normal vector. The shape measurement method (a modified two- illumination-source technique) is discussed and the experimental system is described. An overview of the basic imageprocessingalgorithms, involved in the evaluation of the speckle interference patterns, is given. Improved algorithms concerning phase unwrapping and intensity averaging in the case of low light levels are presented more extensively. Results of shape measurements on a metal cube and a glass bottle are shown. The shape measurement error is estimated at 0.1 mm r.m.s.
A solution is considered of the problem of group point object detection. A model is used which accounts for the density of point object distribution and the form of a spatial region in which the objects are situated. ...
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A solution is considered of the problem of group point object detection. A model is used which accounts for the density of point object distribution and the form of a spatial region in which the objects are situated. On the base of the model is synthesized a simple and sufficiently speed algorithm for group point object detection on the false mark background. An estimation is given of the computational efficiency of the detection algorithm. The conclusion is made that the considered model and obtained algorithms may be used in development of effective speed automated systems for imageprocessing and recognition.
various learning vector quantization (LvQ) algorithms proposed before have made use of the learning coefficient alpha (t) for obtaining convergence of training. The authors present a new method that can be to estimate...
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various learning vector quantization (LvQ) algorithms proposed before have made use of the learning coefficient alpha (t) for obtaining convergence of training. The authors present a new method that can be to estimate the learning rate at alpha (t) from the input and codebook vectors directly and independent of the past history of alpha (t). The results of experiments done with real speech data with the algorithm are also reported.< >
We propose and discuss discrete recurrent algorithms for the retrieval of coherent light fields phase from measurement data of the intensity distribution of their spatial spectra. It is shown that the amplitude. only ...
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We propose and discuss discrete recurrent algorithms for the retrieval of coherent light fields phase from measurement data of the intensity distribution of their spatial spectra. It is shown that the amplitude. only and the phase only light fields are retrieved uniquely from the modules of their Fourier spectrum while introducing in that fields the phase and amplitude masks respectively, satisfying certain conditions. Arbitrary amplitude-phase light fields are retrieved from two modules measurements of their Fourier spectrum, namely, before and after introducing the amplitude phase masks.
A number of imageprocessing and pattern recognition applications demand that a raw digitized binary pattern array be normalized, so that the constituent components of that array are of uniform thickness. The thinning...
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A number of imageprocessing and pattern recognition applications demand that a raw digitized binary pattern array be normalized, so that the constituent components of that array are of uniform thickness. The thinning process reduces such components to a thickness of one pixel, or sometimes a few pixels. This paper describes a strategy for farther enhancing the operational speed of one of the fastest parallel algorithms proposed in the literature.< >
The history of the image understanding environment (IUE) project, a five-year program to develop a common software environment for the development of algorithms and application systems, is reviewed. An overview of som...
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The history of the image understanding environment (IUE) project, a five-year program to develop a common software environment for the development of algorithms and application systems, is reviewed. An overview of some of the data structures that are currently evolving as a specification for the IUE is provided. The ultimate goal of the project is to provide the basic data structures and algorithms that are required to carry state-of-the-art research in image understanding.< >
In this paper a new and efficient method is presented for optimizing the mapping of nonuniform recurrence equations on regular array architectures. The method is based on applying nonlinear transformations on the indi...
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In this paper a new and efficient method is presented for optimizing the mapping of nonuniform recurrence equations on regular array architectures. The method is based on applying nonlinear transformations on the indices of the recurrence equations by reindexing groups of operations based on a chosen group communication scheme. The main result of this paper is that the presented method provides a means to map real life high throughput algorithms onto ASIC regular array architectures under real constraints.
The authors present fast parallel algorithms for computing the histogram on PARBUS and RMESH models. Compared with the approach of J. Jeng and S. Sahni (1992), the proposed algorithm improves the time complexity by us...
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The authors present fast parallel algorithms for computing the histogram on PARBUS and RMESH models. Compared with the approach of J. Jeng and S. Sahni (1992), the proposed algorithm improves the time complexity by using a constant amount of memory in each processing element. In the histogram modification algorithm, the entire range of h is considered. The connections used by the proposed algorithm on the PARBUS model are same as those allowed in the MRN model. Thus, this algorithm runs on this model as well. The results obtained imply that the number of 1's in a N*N 0/1 table can be counted in O(log* N) time on an N*N reconfigurable mesh and in O(log log N) time on an N*N RMESH.< >
This paper addresses the problem of image reconstruction in a subband coding system when certain parts of one or several down-sampled sub-images are missing. By requiring that the sub-images produced from the reconstr...
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This paper addresses the problem of image reconstruction in a subband coding system when certain parts of one or several down-sampled sub-images are missing. By requiring that the sub-images produced from the reconstructed image be similar to those interpolated from the received sub-images, the loss recovery problem has been formulated as a quadratic optimization problem. Two reconstruction algorithms have been developed: a relaxational algorithm that achieves the optimal solution and a fast algorithm that leads to a sub-optimal solution. The interpolation scheme for the sub-images has been derived by characterizing each small image region by a texture or edge model. The proposed algorithms can be applied to any subband system and can accommodate various loss patterns. For the algorithm to work well, the analysis filters should have substantial overlap in their passbands such that the sub-images before down-sampling are correlated. very good results have been obtained with some short kernel filter banks. The reconstructed image is satisfactory even when many parts of the low-low image is missing. It becomes unacceptable only if the lost regions contain certain periodic line structures which can cause Moire patterns in the down-sampled sub-images. The results of our investigation suggest that signal loss problem such as packet loss can be combatted by using subband systems with overlapping filters. Although the coding efficiency is reduced compared to the conventional subband system using non-overlapping filters, the more disastrous signal loss can be prevented.
A consistent, reliable method of quantifying diabetic retinopathy is required, both for patient assessment and eventually for use in screening tests for diabetes. To this end, an algorithm for determining the degree o...
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ISBN:
(纸本)0819407437
A consistent, reliable method of quantifying diabetic retinopathy is required, both for patient assessment and eventually for use in screening tests for diabetes. To this end, an algorithm for determining the degree of venous beading in digitized ocular fundus images has been developed. A parallel implementation of the algorithm has also been investigated. The algorithm thresholds the fundus image to extract vein silhouettes. Morphological closing is used to fill any anomolous holes. Thinning is used to determine vein centerlines. vein diameters are measured normal to the centerlines. A frequency analysis of vein diameter with distance along the centerline is then performed to permit estimation of veinous beading. For the parallel implementation, the binary vein silhouette and the vein centerline are rotated so that vein diameter may be estimated in one direction only. The time complexity of the parallel algorithm is O(N). Algorithm performance is demonstrated with real fundus images. A simulation of the parallel algorithm is used with actual fundus images.
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