Showing papers on "Feature (computer vision) published in 1979"

Thresholding Using the Isodata Clustering Algorithm

Abstract: : A recently proposed iterative thresholding scheme turns out to be essentially the well-known ISODATA clustering algorithm, applied to a one- dimensional feature space (the sole feature of a pixel is its gray level). We prove that in one dimension, ISODATA always converges. We also apply it to requantize images into specified numbers of gray levels.

Image Reconstruction with Limited Angle Projection Data

Abstract: A new image reconstruction technique for computed tomography is described. Projection data obtained by a smaller angle rotation less than 180 degrees around the object are used to make the image. The main feature of the method is the estimation of missing region in the Fourier transformed domain by extrapolation employing analytic continuity. Numerical simulations were carried out using computer generated pattern data. The results show strong effects of the content of noisy component on the reconstructed image. The method might be, however, practically applied to some real fields for medical diagnosis.

The Role of Simple Feature Differences in Infants' Recognition of Faces.

Abstract: The features of a face which define its age or sex appear to play a more important role than do the number of simple feature differences between like aged or same sex faces in the 5- to 6-month infant's recognition of face photos.

"Clonal selection and after," and after.

Abstract: The central feature of the immune system is that it usually manages to distinguish precisely between normal tissue of the body and foreign material. Immunologic destruction of microbial agents and ...

Psychophysical evidence for global feature processing in visual texture discrimination

Abstract: By defining texture as a global feature attained by integration over the image domain, we show that texture discrimination can be predicted for a special class of visual textures (composed of paired dots) as a function of such global features. We derive a psychophysical law based on these global features and show that differences in the variance of orientation, but not of dipole length, result in texture discrimination.

Facial feature variation: Anthropometric data II

Abstract: Facial feature variability as a function of age and gender was explored by using published anthropometric data (adopted by Goldstein, 1979) collected from several samples of faces of three racial groups. In addition, feature variability was compared to feature importance in face identification. Gender differences in variability were small except for Japanese women’s faces, which displayed more variability than other samples in survey. Infants’ faces might be more variable than adults’ faces, but measurement problems cloud the issue. Whether feature variability is related to feature saliency is still unknown because essential information is still missing.

Protective coatings for documents

Abstract: Protective coatings for securing documents from alteration comprising a noncohesive adhesive layer integrated with a verification feature and a method for applying such coatings.

Processing multiple physical features in facial recognition.

Abstract: Subjects made decisions about a series of faces, then had a recognition test The study tasks required a decision about self-reference (does it look like you), an abstract trait (eg, friendliness), a single physical feature (eg, thickness of lips), or multiple physical features (which is the person’s most distinctive feature) As in past research, single physical feature decisions led to poorer performance than abstract trait decisions Of greater interest here, the multiple physical feature condition was significantly better than the single physical feature condition, though still slightly worse than the abstract trait condition These results indicate that the number of features processed is as important to facial recognition as feature “depth,” and that under some circumstances encoding “shallow” attributes can produce durable memory traces

Electro-optical scanning system with self-adaptive scanning capability

Abstract: A scanner profiling system for locating and "mapping" a selected "feature" in a three-dimensional object, which "feature" is nearest with respect to a defined datum plane. The system includes a laser-distancing-instrument (LDI), and a cooperating motor-driven mirror apparatus which is operated under digital computer control to shift the scan axis of the system, in preselected steps, throughout a defined scan field. Object "feature" location, and related scan orientation data which are obtained during a scanning operation, effect computer scan control, whereby scanning "attention", within the total scan field, is directed particularly to "track" the selected "feature".

Progress report of the TUDAB project for automated cancer cell detection.

Abstract: Two methods for high resolution cell image data acquisition are applied routinely. Cells are either scanned by a computer controlled fast scanning microscope photometer (SMP) or a TV-camera. The software system for digital image analysis was completely revised and implemented on the PR 330 minicomputer. The system contains codes for primary cell data acquisition, segmentation of cells, cell feature extraction and statistical cell analysis. With this system, SMP and TV scanned cell data bases of PAP stained cells in vaginal smears, grouped into several classes, have been built up. Each data base contains 34 primary features and 20 feature combinations for each cell. A linear discriminant analysis is applied routinely for cell classification. The present state of the system and its operation are described, cell features and classification results are shown, and future steps for a prescreening strategy are discussed.

Image Feature Extraction Using Diameter-Limited Gradient Direction Histograms

Abstract: Features extracted by operators which examine diameter-limited gradient direction histograms are important because they describe images of industrial workpieces efficiently and have the potential for rapid computation via special purpose hardware. When such operators are passed over an image in raster fashion, features such as the following are detected: a strong peak in the direction histogram indicating the presence of a relatively straight edge, a second strong direction indicating a corner, a wide direction group indicating a curved edge, and a uniform distribution of directions over the histogram indicating small holes. Diameter-limited optimization can be used to substantially reduce the number of pixels which have been given feature labels by such operators without losing descriptive power. Feature labels for direction histograms having a second strong direction, a wide direction group, or a uniform distribution might be retained only if all other pixels within a circular aperture have a lower bin value. Pixels with a strong direction label might be retained only if all other pixels within a circular aperture and along the gradient direction have a smaller bin value. Tracking can then be applied to the remaining strong direction pixels in the direction perpendicular to the gradient to achieve representation of edges by endpoints. Experimental results indicate that descriptions which are compatible with human interpretation can be achieved.

Method and apparatus for character reading

Abstract: A method for character reading requiring no character segmentation, which method effects required character recognition by the steps of subjecting a given string of character patterns to continuous scanning to produce either a local feature vector at each of the intersections of rows and columns of character patterns or a global feature vector for each of the columns formed in consequence of the scanning, linearly consolidating either or both of the feature vectors to obtain a lower dimensional vector in new feature axes and continuously matching the vectors with the standard ones set in advance.

Numerical evaluation of cytologic data. III. Selection of features for discrimination.

Abstract: The proper selection of variables is important in assembling a profile to best describe a given group, whether of patients or cells, vis-a-vis other groups. The need often arises to determine which variables in comparable profiles best discriminate between the profiles. Three techniques for the evaluation and selection of variables on the basis of their potentiality for discrimination are discussed in this article. The Kruskal Wallis test is useful in determining if a certain feature (variable) has any statistical significance between groups. The ambiguity function after Genchi and Mori and the measure of detectability (d') are discussed as direct measurements of a feature's ability to discriminate between groups. Fully worked numerical example suitable for execution on a pocket calculator are given.

The Economics of the Television Market for Theatrical Movies

Abstract: The new bargaining strategy of network bidding for feature films before their theatrical release is a logical extension of the networks' activities in the regular TV programming market.

High-Accuracy Model Matching For Scenes Containing Man-Made Structures

Abstract: A feature-based scene-matching technique is described that was developed for autonomous airborne guidance systems. Reference and sensed models of scenes containing man-made structures are matched using line and vertex features derived from the scenes. Feature weighting, based on model feature content and matchpoint location, is used in performing transformations between the reference and sensed models that lead to high-accuracy matchpoint location in the sensed scene.© (1979) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

19-Hydroxy-PGI2 compounds

Abstract: Prostacyclin and prostacyclin-type derivatives having a 19-hydroxy feature are disclosed, including processes for preparing them and the appropriate intermediates. The compounds are useful for pharmacological purposes such as inhibition of blood platelate aggregation.

Electrical fuze with a plurality of modes of operation

Abstract: A feature of this invention is the provision of a fuze having a plate which serves both as a full frontal area impact switch and an electrostatic sensor to provide detonation signals.

On the determination of boundary-layer parameters using velocity profile as the sole information

Abstract: This paper proposes a numerical technique based on the ‘least-square error method’ for evaluating fluxes and other surface-layer parameters. The special feature of this method is that it requires no a-priori knowledge of either the temperature profile or the roughness length z0. The accuracy of the method has been tested on both the Kansas and the Wangara experimental data. Results obtained compared favourably with those from direct measurements as well as from other studies using conventional approaches.

Automatic Fingerprint Identification

Abstract: The present system for identifying latent fingerprints left at the scene of a crime still depends on the skill and patience of trained fingerprint technicians because of the low quality of the latent fingerprints. An image processing & feature extraction technique has been established in order to detect minutiae (ridge endings and ridge bifurcations and ridge counts useful for latent fingerprint identification. The algorithm of the latent fingerprint identification using these features has been evaluated. Each feature is detected from the gray scale image of fingerprints and described by minutiae positions, minutiae directions and interminutia ridge counts. In the latent fingerprint identification, minutiae pairs are selected according to the similarity between latent fingerprints' features and registered fingerprints' features in a file. The similarity between two fingerprints is obtained through the comparison of selected minutiae pairs. In our experiments, we attempted the feature extraction of 500 registered fingerprints and 200 latent fingerprints, and the matching between them. The experiments were carried out using a high speed microcomputer, a flying spot scanner, a color display, and a tablet unit, which con-nected with a general purpose computer system (NEAC 2200/200).

19-Hydroxy-19-methyl-PGI2 compounds

Abstract: Prostacyclin and prostacyclin-type derivatives having a 19-hydroxy feature are disclosed, including processes for preparing them and the appropriate intermediates. The compounds are useful for pharmacological purposes such as inhibition of blood platelate aggregation.

Online character feature extractor

Abstract: PURPOSE: To discriminate between similar characters by detecting even a slight difference in stroke by extracting as the feature value of a character a time series of four kinds of feature values, i.e., stroke linearity, a relative length ration, an angle of a direction from an initial point to a terminal point, and a change in curvature angle of the stroke. CONSTITUTION: A unit which extracts features regarding strokes of an online character expressed by a time series of strokes expressed by a sequence of representative points is provided with stroke-feature extracting circuit 1. This extracting circuit 1 is provided with linearity extracting circuit 2 which extracts the linearity of each stroke, length-ratio extracting circuit 3 which extracts length ratios, direction angle extracting circuit 4 which extracts the angle of the direction from an initial point to a terminal point, and angle-change extracting circuit 5 which extracts the angle change showing the curvature of each stroke, thereby applying extracted feature values to stroke feature storage buffer 7. Then, a slight difference between strokes is detected by each feature value to discriminate between similar characters correctly. COPYRIGHT: (C)1980,JPO&Japio

Effectiveness of feature groups for automated pairwise leukocyte class discrimination.

Abstract: Automated blood cell differentials using statistical classification techniques have been implemented in several commercial machines. The machine-derived features used to classify leukocytes resemble the descriptors used by humans performing visual classification, e.g. size, content, shape, color, and texture. However, because of our crude modeling of vision there is no universally accepted measure of characteristics such as shape, color, or texture. One expects, therefore, that features which are powerful discriminators for humans may perform poorly when quantified by machine, while other parameters may be more precisely measured automatically and so prove more useful in cell classification. This paper reports the results of a feature evaluation study for automated discrimination between all pairs of a large set of leukocyte classes consisting of both normal and abnormal types. To provide a framework for comparing automated feature ordering with the ranking attached by medical technologists, the machine-derived features were divided into six groups: size and content, mean and mode, cytoplasm/nucleus comparison, contrast and texture, color, and nuclear shape. A sequential procedure was used to select the best five-feature set from each group and the globally best five-feature set for each pairwise classification. The results illustrate the strengths and weaknesses of machine-derived descriptors for each type of decision.

Automatic determination of image-to-database correspondences

Abstract: New techniques are described for some of the important computations in the automatic determination of image-to-database correspondences. In particular, a technique to predict a region in the image within which a feature is expected to appear, a set of techniques to verify feature matches, and a technique to extend the refinement process to include a new type of match based on linear features, such as roads, are discussed. These techniques are demonstrated in an example in which the system reduces the uncertainties from approximately plus or minus 200 feet on the ground to approximately plus or minus two feet.

STORE IMAGE: How departmental images differ in a variety chain

Abstract: There have been a number of studies of store image (especially in the US), some of which have thrown up useful definitions. But so far relatively little has been done to establish what difference may exist in image as far as different departments of a variety store are concerned. In this special feature, Peter McGoldrick discusses a survey carried out in a Manchester Marks & Spencer store which examined customers' perceptions of image, and looks at the implications for management.