0000000000545541
AUTHOR
Bernard Lamalle
showing 10 related works from this author
Rétine Vidéo Rapide Réalisée en Technologie CMOS
2008
Nous présentons une rétine réalisée en technologie CMOS 0.6 μm dédiée à l’observation de phénomènes lumineux rapides. Le pixel que nous avons conçu est basé sur un principe de modulation de la durée d’une impulsion représentative du flux lumineux incident. Ce pixel a été validé par simulation SPICE grâce aux bibliothèques AMS du fondeur puis dessiné en full- custom de façon à optimiser sa surface, on a obtenu ainsi un pixel dont la dimension est de 49.2μm de coté avec un taux de remplissage de 18 %.
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 …
A Continuous Time Pattern Recognition Retina
2002
International audience; We present in this paper a pattern recognition retina operating in continuous time. During a programming phase, the reference image is acquired by the sensor. After thresholding, the resulting binary image is stored in the sensor's pixels. During the recognition phase, the retina calculates, in an analog way and in continuous time, the zero displacement intercorrelation of the current image with the binary reference image and its complement. These two intercorrelation values are output as currents. By comparing these currents to expected values, determined during the programming phase, a shift of the pattern or a difference between the observed and programmed pattern…
A Correlation Retina in Standard 0.6um : Application in Positioning System
2003
International audience; We have designed and fabricated a programmable retina that is capable of recognizing patterns stored in memory in real-time. Each of the pixels of the retina is composed of a photodiode and an electronic device used during the programming phase to digitize the image of the pattern to recognize into a binary image stored in latches. The array of pixels is thus partitioned into two complementary disjoint sub-sets with all the photodiodes of the same sub-set connected together in order to obtain the sum total of the currents. During the analysis phase, an optical correlation between the projected image and the reference binary image memorized in the circuit is done. The…
Hardware Computation of Moment Functions in a Silicon Retina Using Binary Patterns
2006
International audience; We present in this paper a method for implementing moment functions in a CMOS retina for shape recognition applications. The method is based on the use of binary patterns and it allows the computation of different moment functions such geometric and Zernike moments of any orders by an adequate choice of the binary patterns. The advantages of the method over other methods described in the literature is that it is particularly suitable for the design of a programmable retina circuit where moment functions of different orders are obtained by simply loading the correct binary patterns into the memory devices implemented on the circuit. The moment values computed by the m…
A CMOS Image Sensor Design for Speed Determination of Fast Moving Luminous Objects
2003
International audience
Dimensional control of metallic objects by artificial vision: contribution to lighting condition studies
1999
We present an original method that enables real time automatic dimensional control of defects on metallic objects. The method is based on the theoretical and experimental study of light reflection mechanisms that can be seen as a function of the surface roughness and of the light source size. We show that it is possible to reconstruct the profile of an object from a single gray level image. An industrial application enables us to validate our results. Finally, an error computation fixes the limits of our method and enables us to better understand illumination problems.
Study of the imaging conditions and processing for the aspect control of specular surfaces
2001
A vision system capable of imaging and detecting defects on reflective nonplanar surfaces in the production line at a high cadence is presented in this paper. Defects are typically dust located under the metallic layer of packaging products used in cosmetic industries. To realize this processing, structured lighting which reveals the defects in the image is proposed. Defects appear clearly in the images like a set of brilliant pixels in dark zones. The signature of the defect is then obtained. The size of this signature does not depend linearly on the size of the defect. It is a function of the observation angle. In order to realize a precise and robust process, the necessity of acquiring s…
Masquer l'Objet pour Mieux le Reconnaître
2005
National audience; L’évolution des technologies de pointe a repoussé les limites des domaines d’application de l’imagerie numérique de sorte que les capteurs d’images sont aujourd’hui omniprésents dans beau- coup d’applications, que ce soit des applications scientifiques ou des appli- cations liées au divertissement et à un usage grand public. Ces capteurs four- nissent en général une image qui est par la suite traitée par un ordinateur ou des circuits électroniques spécialisés. La course vers la miniaturisation et vers des systèmes autonomes compacts et légers nécessite aujourd’hui des cap- teurs d’images de plus en plus petits et de faible consommation. De plus, il existe des applications…
Reconnaissance de la Forme 3D et Estimation de la Profondeur Implémentation sur FPGA Spartan 3A d'un SoC pour la Vision 3D (Shape From Focus) Problém…
2007
Le terme de « vision 3D » ou « de numérisation 3D », est apparu à la fin des années 1990, pour désigner des techniques d'acquisition de mesures tridimensionnelle sur des surfaces, techniques ayant la caractéristique de donner des nuages de points denses et importants dont l'ordre de grandeur est de quelques dizaines à plusieurs millions de points. Le nuage de points représente en fait l'information de l'image de profondeur et selon des différents traitements à l'image on peut aboutir à un ordre de précision de la reconstitution de l'objet ou scène en 3D. La vision 3D demeure une méthodologie de base pour réassurer le mécanisme de reconstitution des images tridimensionnelles. Outre les besoi…