Search results for "Artificial vision"
showing 10 items of 21 documents
Digitization and characterization of local reflectance of complex surfaces for visual inspection
2022
Mastering the visual perception of the surfaces of manufactured products is a central issue for industry. However, in industry, the quality of surfaces is often assessed by human inspectors. Only a few specific cases use an instrumental or photometric approach. Among the photometric approaches, one of them is experiencing significant growth: Reflectance Transformation Imaging (RTI). The RTI makes it possible to obtain a reduced and simplified estimate of the Bidirectional Reflectance Distribution Function (BRDF) and an estimate of the geometry of the surface. However, this technique has limitations in terms of data acquisition and processing. The objective is therefore to correct some of th…
Special Section on Quality Control by Artificial Vision
2008
This PDF file contains the editorial “Editorial: Special Section on Quality Control by Artificial Vision” for JEI Vol. 17 Issue 03
Apparence des matériaux, Vision artificielle, Inspection qualité, Reflectance Transformation Imaging
2022
Mastering the visual perception of the surfaces of manufactured products is a central issue for industry. However, in industry, the quality of surfaces is often assessed by human inspectors. Only a few specific cases use an instrumental or photometric approach. Among the photometric approaches, one of them is experiencing significant growth: Reflectance Transformation Imaging (RTI). However, this technique has limitations in terms of data acquisition and processing. The objective is therefore to correct some of these limitations in order to improve the RTI and, consequently, the visual quality control of surface conditions in industry.The current RTI systems are limited and cannot meet our …
Development and implementation of a selective change-driven vision sensor for high speed movement analysis
2013
Un sistema de vision artificial esta compuesto, en su forma más basica, por un sensor VLSI, habitualmente fabricado en tecnología CMOS o CCD, y una etapa de procesado. En la gran mayoría de los sistemas de visión artificial implementados hoy en día la etapa sensora del sistema consiste en un sensor de imágenes tradicional. Este tipo de sensores trabajan bajo unos principios muy simples y conocidos: el nivel de iluminación del entorno es muestreado y transmitido a intervalos de tiempo regulares; y todos los píxeles de la matriz, sin excepción, son transmitidos secuencialmente y en orden. Esto es así aunque no se hayan producido cambios en la escena bajo observación. Esto implica que una gran…
Shape Reconstruction of Metallic Objects by Artificial Vision
1997
Quality control in industrial applications has greatly benefited from the development of tools like artificial vision. The artificial vision approach of quality control has the advantage of being able to perform both non-destructive and contactless controls as well as to work mostly in real time. However, in the case of non planar objects to be controlled, dimensional control may become hard to realize. Indeed, due to the bidimensional aspect of the images, a loss of information is unavoidable. Consequently, obtaining depth information from a planar image is not obvious. Most of the existing methods use several cameras1 or several light sources2, this leads to an increase in the processing …
Understanding dynamic scenes
2000
We propose a framework for the representation of visual knowledge in a robotic agent, with special attention to the understanding of dynamic scenes. According to our approach, understanding involves the generation of a high level, declarative description of the perceived world. Developing such a description requires both bottom-up, data driven processes that associate symbolic knowledge representation structures with the data coming out of a vision system, and top-down processes in which high level, symbolic information is in its turn employed to drive and further refine the interpretation of a scene. On the one hand, the computer vision community approached this problem in terms of 2D/3D s…
Innovative modelling techniques in computer vision
1996
Abstract The paper is concerned with two of main research activities currently carried on at the Computer Science and Artificial Intelligence lab of DIE. The first part deals with hybrid artificial vision models, intended to provide object recognition and classification capabilities to an autonomous intelligen system. In this framework, a system recovering 3-D shape information from grey-level images of a scene, building a geometric representation of the scene in terms of superquadrics at the geometric level, and reasoning about the scene at the symbolic level is described. In the second part, attention is focused on automatic indexing of image databases. JACOB, a prototypal system allowing…
Symmetry as an Intrinsically Dynamic Feature
2010
Symmetry is one of the most prominent spatial relations perceived by humans, and has a relevant role in attentive mechanisms regarding both visual and auditory systems. The aim of this paper is to establish symmetry, among the likes of motion, depth or range, as a dynamic feature in artificial vision. This is achieved in the first instance by assessing symmetry estimation by means of algorithms, putting emphasis on erosion and multi- resolution approaches, and confronting two ensuing problems: the isolation of objects from the context, and the pertinence (or lack thereof) of some salient points, such as the centre of mass. Next a geometric model is illustrated and detailed, and the problem …
Fast Image Mosaicing for Panoramic Face Recognition
2006
In this article, we present some development results of a system that performs mosaicing (or mosaicking) of panoramic faces. Our objective is to study the feasibility of panoramic face construction in real-time. To do so, we built a simple acquisition system composed of 5 standard cameras which, together, can take simultaneously 5 views of a face at different angles. Then, we chose an easily hardware-achievable algorithm, consisting of successive linear transformations, in order to compose a panoramic face from these 5 views. The method has been tested on a relatively large number of faces. In order to validate our system of panoramic face mosaicing, we also conducted a preliminary study on…
Conception en technologie CMOS d'un Système de Vision dédié à l'Imagerie Rapide et aux Traitements d'Images
2008
Our work presented in this thesis focuses on the design, testing and implementation of monolithics CMOS image smart sensors : The principle, performance and limitations. The hardware implementation of a vision smart system is the central link. HISIC is High Speed Image Capture with processing at pixel level. An experimental platform for instrumentation and evaluation of retina operators was conducted during this thesis. After a state of the smart sensors and CMOS retinas, the second part is dedicated to the study and design of the pixel image sensor HISIC. Two circuits were realized in CMOS technology. The first identied a new type of photo-detector, and the second, to create a prototype em…