Visual Data Processing Research Articles

Effects of synthetic delta9-tetrahydrocannabinol on binocular depth inversion of natural and artificial objects in man.

Binocular depth inversion represents an illusion of visual perception that is sensitive to various behavioural and psychiatric conditions. It is affected by cannabinoids, reflecting associated changes in perception. The present study investigated the differences in binocular depth inversion of different classes of natural and artificial objects and the effect of synthetic delta9-tetrahydrocannabinol (Dronabinol) on these illusionary perceptions. Using this model, the effects of orally administered Dronabinol on binocular depth inversion were investigated in 17 healthy male volunteers. Pictures from natural and artificial objects were presented stereoscopically and the depth perception of the volunteers was scored in an operationalized way. The timecourse of the effects of Dronabinol on binocular depth inversion was analyzed with regard to the stimulus classes (natural and synthetic objects). Significant differences in binocular depth inversion of the different groups of stimuli were revealed. Objects with a higher degree of everyday familiarity were generally seen as more illusionary than those with a lower degree of everyday familiarity. A strong impairment of binocular depth inversion due to Dronabinol was found in most classes of objects. Analysis of different stimulus classes provides further information on the underlying perceptual processing of binocular depth inversion. An impairment of top-down processing of visual sensory data by Dronabinol is suggested. The anandamidergic system seems to be involved in areas of visual information processing.

Structure of Perseids from visual observations

A new method of processing of visual meteor data has been worked outand applied to Perseid meteor shower observations. Reduced meteor hourly rates with magnitudes brighter than +3 are proportional to meteor flux densities with a coefficient equals to the effective collecting area. Corrections due to moon light and for meteor path lenghts were applied. Our observations 1972–1979 and 1982–1990 gave similar hourly rate profiles with a maximum rate of 71 meteors at solar longitude L=140.36°. Perseids 1980 and 1981 were about 1.5 times more active. The maximum Perseid activity in 1991–1992 was 119 meteors at solar longitude 139.54° and narrow peaks are observed at the same longitude showing an enhanced activity up to 225 meteors.

Closed-Loop Simulation of a Vehicle System with an Artificial Driver*

ABSTRACT In this paper, a model for closed-loop simulation of a driver-vehicle-road system that employs the visual data processing method is suggested. In the model of a human driver, the human capability of learning to negotiate the curved road is simulated using a neural network technique. The learned network extracts an equivalent curvature from the viewing image of the frontal road. This equivalent curvature becomes a control cue for steering action. For computer simulation of the driver-vehicle-road system, a mathematical model of a vehicle with Fifteen degrees of freedom is established using the suspension super-element concept, which can handle the three-dimensional motion and suspension kinematics of a vehicle system efficiently. To validate the model of the driver-vehicle-road system, an actual driving test is performed and the results are compared with those from the computer simulation of the model.

Intelligent vision system to control flexible assembly cell feeding processes

A vision system which is installed at an assembly cell to detect its feeding system must analyze objects for inspection and assembly operations. This means that a description of the objects must be generated. A particular analytic technique may be characterized by the nature of the formal description generated, by the computation techniques employed and by the degree to which the formal description accurately reflects pertinent information about the object. To execute assembly tasks, the part identification, orientation, spatial position and geometric features were calculated. For inspection tasks, a list of deviations between the observed object and a reference object was generated to determine whether a part could proceed into the assembly cell. Since the vision system is associated with real-time assembly cell operations, its vision data processing time must be minimized. Therefore, intelligent processing techniques must be developed. Such techniques are provided by the developed knowledge-base and inference engine. The described vision system which is incorporated with the knowledge base and the inference engine is referred to as an “intelligent vision system”. The developed intelligent vision system was implemented in a simulation program to inspect the feeding systems of pneumatic motor assembly cells. The results support known interrelationships between parameters associated with detected assembly processes, and verify the reliability of the developed inference engine reasoning algorithms. Since the simulation was programmed in generic terms, it is not limited to a specific product but can be applied to a large variety of products.

フリーフライングロボットによる視覚情報を用いたターゲットの捕獲

This paper deals with a free-flying space robot which grapples a target satellite based on a visual feedback control scheme. As the robot body is not fixed in an inertial space, manipulator motion causes changes in the view of the visual sensor. Therefore the closed loop system for the manipulator controller involves the visual data processing which normally takes long calculation time. We construct a control system which is not explicitly affected by the calculation time and analyze stability of the system. Analysis results show that a stable control system can be constructed in spite of the long calculation time, on condition that the manipulator trajectory which is not close to singular points is settled. Moreover we developed a zero gravity motion simulator which combined a computer simulation and servo mechanisms. An experimental space robot system is constructed and experiments to grapple a target are performed on the simulator. It is confirmed through the experiments that the free-flying space robot automatically grapples the target with the visual feedback control scheme proposed.

Gaze motor asymmetries in the perception of faces during a memory task

In 33 male and female adult volunteers, eye position recording were performed by means of an infrared reflection technique. Slides of randomly shuffled black-and-white photographs (7.5 × 10°)of faces and vases were projected for 6 or 20 sec respectively in a visual memory task. In each series, 10 slides of art nouveau vases and of the “inner part” of masked Caucasian faces were used. During recording the head was fixed by a bite-board. 1. (a) For faces the preferred targets of the centre of gaze were the eyes, the mouth and nose region, for vases the contours and some prominent ornaments. 2. (b) Left-right asymmetries in the gaze-movement sampling strategy appeared with faces, but not with vases. In faces, the overall time that the centre of gaze remained in the left half of the field of gaze was significantly longer than in the right half. 3. (c) When, however, the amplitude of the gaze excursions into the left and right halves of the inspected items was taken as a measure and normalized, a preference for the right gaze field was observed. 4. (d) The relative left-right bias during face inspection was stronger with the 6 sec than with the 20 sec inspection period and significantly stronger in female than in male subjects for the 6 sec tasks. 5. (e) Left/right inversion of the face stimuli did not abolish the side bias. Thus the asymmetric sampling strategy when faces were inspected as compared to vases was due to “internal” factors on the part of the subjects. It is hypothesized that a left-right asymmetry in hemispheric visual data processing for face stimuli was the cause of a left-right asymmetry in gaze motor strategies when faces were inspected.

Quality control functions of the Visual Field Reading Center (VFRC) for the Optic Neuritis Treatment Trial (ONTT)

The Visual Field Reading Center (VFRC) was established to assess visual field testing in the Optic Neuritis Treatment Trial (ONTT), to train and certify ONTT technicians, and to monitor the quality of the visual fields through evaluation of the technical aspects of the visual field testing. We describe the functions of the VFRC personnel and the standardized test protocols developed by the VFRC for Humphrey and Goldmann perimetry. We also describe the VFRC procedures for training and certifying visual field technicians, double-checking the eligibility of ONTT patients, assessing the quality of the visual field data, and processing visual field data. In addition, we describe the principles applied by the director and associate director of the VFRC in their clinical classification of the various localized and diffuse visual field defects observed in the Humphrey and Goldmann visual fields. The VFRC has processed more than 14,000 Humphrey and Goldmann visual field tests. The visual field quality control procedures and visual field defect classification process have been shown to be quite reproducible. Through quality control assessment procedures, we have been able to pinpoint a variety of problems at an early stage and promptly implement corrective measures. The standardized test protocols, technician training and certification procedures, and quality control assessment techniques used by the VFRC for the ONTT may serve as a model for future clinical trials employing visual field data as an outcome measure. These procedures can also be used to enhance visual field reliability in ophthalmological practices.

Emergence of orientation selective simple cells simulated in deterministic and stochastic neural networks.

The processing of visual data in area 17 of the mammalian cortex is mainly performed by cells with receptive fields which are tuned to different orientations of input stimuli. The mechanisms underlying the emergence of receptive field properties of orientation selective cells are not well understood up to now. Recently, some models for the prenatal development of the receptive fields of orientation selective simple cells have been proposed, which emerge in neural networks trained by Hebb type unsupervised learning rules. These models, however, use different network architectures and are restricted to the case of identical input neurons. In this work, a biologically motivated neural network model with a general architecture is presented. It is trained with a Hebb type updating rule and with uncorrelated input. The input neurons are identified with retinal ganglion cells and exhibit mature Mexican hat type receptive fields. If the receptive fields of the input neurons have identical properties (deterministic model), a set of parameter domains is found, which characterize different kinds of receptive field maturation behaviour of the network. Results obtained by other authors with similar models are contained in this description as special cases. In addition, the more general and rarely investigated stochastic model, where random variations of the parameters describing the receptive fields of the input neurons occur, is investigated. A high sensitivity of the network against these random variations is obtained. In case of large variations of receptive field parameters of the ganglion cells, a qualitatively new kind of maturation behaviour appears. A significant part of the synaptic connections from ganglion cells to the cortical cell is removed and small simple cell receptive fields with only few lobes emerge. The stochastic model is found to provide a better description of the size, scatter and structure of receptive fields present in biological systems, than the deterministic model.

Visual language and software development environment for image processing

AbstractThe Khoros system integrates multiple user interface modes, code generators, instructional aids, data visualization, and information processing to produce a comprehensive image processing research tool. This system can easily be tailored to other application domains because the tools of the system can modify themselves as well as the system. This attribute is important in a system that is designed to be extensible and portable. The Khoros infrastructure consists of three major components: a high‐level user interface specification, methods of software development embedded in a code generation tool set, and an interoperable data exchange format and algorithm library. These basic facilities have been used to build a set of applications for performing image processing research, algorithm development, and data visualization. One of the most powerful features of the system is its high‐level abstract visual language. Khoros is a successful demonstration of how development programming, end‐user applications programming, information processing, data display, instruction, documentation, and maintenance can be integrated to build a state‐of‐the‐art image/data processing and visualization software environment.

Industrial Robot Vision System

The paper describes the results of developing and testing of a simple, cheap and fast reacting system of technological vision, necessary for solving applied tasks of visual data processing, connected with the utilizing of industrial robots for manufacturing processes.

Computer processing of visual field data. I. Recording, storage, and retrieval.

A minicomputer system has been developed to provide real-time management of visual field data. Records of a large population of patients with glaucoma in a university ophthalmic practice are stored on magnetic disks. Data storage has been semiautomated by means of a microprocessor-controlled recording device for standard perimeters. Existing visual field records may also be digitized by means of a magnetic graphics tablet. Records are retrievable in real time and are graphically displayed at video terminals.

Visual Scanning, Pattern Recognition and Decision-making in Pulmonary Nodule Detection

Eye movements were recorded while four subjects searched a set of 60 films, 24 normal and 36 abnormal for pulmonary nodules. Error rates, scanning patterns and the dwell time of fixation clusters on normal and nodule-containing areas of the film were studied. Using the assumption that prolonged dwell time indicates intensive processing of visual data, a model was developed for nodule detection that includes four steps: orientation, scanning, pattern recognition and decision-making. False-negative errors were divided into three classes: scanning errors, recognition errors and decision-making errors. Of 20 false-negative errors, 30% were considered scanning, 25% recognition and 45% decision-making.

L'analyse typologique des comportements financiers des communes : le cas de la banlieue stéphanoise

Visual data processing for local finances ; an example from the surroundings of St Etienne. — Simple visual combinations between financial ratios produce information which is too fragmentary. Without a statistical analysis visual correlations between communal financial profiles permit the development of typologies and isolate . the most significant ratios : surplus vs. revenue, the internal interest rate, the investment and debt per inhabitant. The cartography of these types has the merit of identifying the meaning of mutations which occur on the outskirts of a town. However, one should exercise caution in considering the commune as an element of the socio-political system rather than as an economic enterprise.

L'utilisation des matrices ordonnables par les géographes français (1967-1976)

The use of orderable matrix by French geographers (1967-1976). — This article presents an annoted select bibliography of the works of French geographers who have made use of the « orderable matrix ». The present situation is analysed, as are the prospects of using visual data processing methods.

Dyslexia and specifically distorted drawings of the face - a new subgroup with prosopagnosia-like signs.

Identification of a subgroup (38%) of dyslexics (new syndrome?). These, against controls (5.5%), drew 'neolithic' face configurations analogous to those visually experienced in prosop-agnosia. Essential symptoms of this subgroup are seen as result of specific early ways of processing visual data: lexical shapes (letters, words) and facial features, as if these were concrete entities, not abstract component parts. Thus, with letters, taken as entities, d = q, d = b, N = Z.

Spatio-temporal differentiation and integration in visual motion perception. An experimental and theoretical analysis of calculus-like functions in visual data processing.

Perceptual organization during short tachistoscopic presentation of stimulus patterns formed by ten moving bright spots, representing a human body in walking, running, etc. was investigated. Exposure times were .1 sec to .5 sec. The results reveal that in all Ss the dot pattern is perceptually organized to a “gestalt”, a walking, running, etc., person at an exposure time of .2 sec. 40% of Ss perceived a human body in such motion at presentation times as short as 0.1 sec. Under the experimental conditions used the track length of the bright spots at the threshold of integration to a moving unit was of the size order 10′ visual angle. This result is regarded as indicating that a complex vector analysis of the proximal motion pattern is accomplished at the initial stage of physiological signal recording and that it is a consequence of receptive field organization. It is discussed in terms of vector calculus.

Measuring two-dimensional complexity: A conceptual structure

Two-dimensional complexity is viewed as being analyzable through two-dimensional syntax. This premise is based on the assumption that there is a natural two-dimensional language, which is used for visual data processing and pattern recognition. Based on these assumptions, three measures of syntactic complexity, developed for context-free grammars, are shown to have application to Dacey's two-dimensional languages for simple polygons.

Report on Progress in the Development of Visual Prostheses

□ In summary, we can say that as a result of recent work in implanting visual prostheses in correlated work in visual physiology, data processing, and materials technology and in the development of sophisticated simulation techniques, we have approached several steps closer to a vantage point from which we can state the conditions under which a reliable visual prosthesis in the armamentarium of sensory aids has been clarified as a result of the conference and the interest of the scientific community in the development of such a system has been stimulated. It is significant that Dr. MacNichol (the new director of NINDS) has made our computer program for simulating the output of a prosthesis available to scientists at the National Institutes of Health as well as members of the newly-formed National Eye Institute. It is also obvious that we can sustain scientific interest in the problems involved in the development of experiments toward a visual prosthesis, because of the simultaneously human and personal involvement of researchers in alleviating the problems of blindness.

Conceptions nouvelles en matière de mesures limnimétriques sur les cours d'eau

The running of a hydrometric network is discussed within its theoretical setting under such varied aspects as the measurement of stage/discharge data, their collection of transmission, conversion of 'stage' data into 'discharge' data, processing and publishing the latter, and general data classification and filing. The French Ministry of Agriculture's aims and purposes are discussed with regard to the requirements of its gauging network ; optimal features of stage measurement equipment or 'level recorders are prominent among the points explained. A complete list of stage recording equipment available on the market is subjected to a critical analysis with a view to ascertaining whether it meets present gauging network requirements, and it is found that there are several gaps requiring new types of equipment. At least three European firms have produced prototypes (Neyrpic and S.F.I.M.) or modified an existing level recorder (Ott, type 20 060). All this new equipment is under test at the time of writing. The author gives some additional information on the prototype equipment, i.e. the Neyrpic pneumatic remote-reading level recorder and the S.F.I.M. strain gauge pressure pick-up recorder. Both manufacturers are considering an I.B.M. tape code print-out system enabling visual data-processing. The article ends with discussion of the main lines along which a complete control 'sequence' for a gauging system might run, in theory, allowing for data-processing requirements. Five such sequences are presented in detail, being both suitable for the French Ministry of Agriculture's requirements and feasible with present available standard or prototype equipment.

Seismic data collection, reduction, and digitization

AbstractThe facilities set up at the Bell Telephone Laboratories for seismic data collection and reduction are described. The digitization of the data so collected was carried out with existing equipment used for processing speech and visual data. We consider the seismic instrumentation and telemetry set up at the Chester Field Laboratory, Chester, New Jersey, the observation and recording equipment installed at the Murray Hill Laboratory, and finally and digitization and associated computer reduction to punched card form.