Search results for " processing"

The ALICE experiment at the CERN LHC

2008

Journal of Instrumentation 3(08), S08002 (2008). doi:10.1088/1748-0221/3/08/S08002

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…

Brain's capacity to detect abstract regularities from visual stimuli under different attentive conditions- an ERP study

2010

Many previous studies have applied oddball paradigm to study change detection. Although changes within single features have been investigated a lot, the changes in multiple feature conjunctions have not. The aim of our study was to investigate with event-related potentials by applying oddball paradigm, whether the brain can detect abstract regularities in visual stimulus stream when two different features are combined - semantic meaning and color. Participants were shown adjective words written in red and blue print in quasi-random order on a computer screen. In an oddball paradigm, 90 % of the words (‘standard’) followed the rule “words printed in red have a negative meaning and the words …

Editorial : Visual mismatch negativity (vMMN) : A unique tool in investigating automatic processing

2022

Event-related potentials to task-irrelevant changes in facial expressions

2009

Abstract Background Numerous previous experiments have used oddball paradigm to study change detection. This paradigm is applied here to study change detection of facial expressions in a context which demands abstraction of the emotional expression-related facial features among other changing facial features. Methods Event-related potentials (ERPs) were recorded in adult humans engaged in a demanding auditory task. In an oddball paradigm, repeated pictures of faces with a neutral expression ('standard', p = .9) were rarely replaced by pictures with a fearful ('fearful deviant', p = .05) or happy ('happy deviant', p = .05) expression. Importantly, facial identities changed from picture to pi…

Issues in Visual Science

2004

Sélection de bandes pour la visualisation d'images spectrales : une approche basée sur l'étude de saillance

2011

National audience; De nos jours, la plupart des technologies d'affichage numériques sont basées sur le paradigme qu'une combinaison de trois couleurs primaires spécifiques est suffisante pour la reproduction d'une couleur quelconque pour l'oeil humain. Par ailleurs, les dispositifs d'affichage multispectraux ne sont pas encore monnaie courante sur le marché du multimédia. Ainsi, lorsqu'il s'agit de visualiser une image spectrale en couleur, sur un écran traditionnel, seuls trois bandes peuvent être utilisées simultanément, ce qui implique une réduction de dimensionnalité. Cette étape doit permettre la préservation d'un maximum de contenu informatif tout en préservant contrastes et couleurs …

Sing and Measure: Sound as Voice as Quanta

2022

The universal concept of a “music of the spheres” traverses the history of philosophy, science and art, from Pythagoras to Kepler and beyond. In modern times, a sphere in three dimensions—the Bloch sphere—is used to illustrate the state of a qubit, the basic unit of quantum information. On the same spherical surface, the fundamental components of voice production can be located, so that any utterance can be seen as the evolution of a unit two-dimensional vector having complex coefficients. Indeed, any sound can be analyzed and decomposed into overlapping sinusoidal components, broadband noises, and impulsive transients, which in turn can be associated to fundamental means of vocal sound pro…

Relationship between volume and energy of vector fields

2001

Abstract A unified study of energy and volume functionals is presented here by determining the critical points of a functional that extends simultaneously energy and volume and that is defined on the product of the manifold of smooth maps C∞(M,N) times the manifold M of riemannian metrics on M. The restriction of this functional to different submanifolds of the space of vector fields X (M)× M is also considered, and used to study several functionals generalizing volume and energy or total bending of vector fields

Webcam based display calibration

2012

International audience; We present an automatic method for measuring the tone response curve of display devices based on visual methods, where the eye is replaced by an end-user, uncalibrated camera, such as a webcam. Our approach compares a series of halftoned patches of known covering ratio with a continuous series of tone patches for each ratio. Both patches are shot by a camera that is used as a virtual eye to evaluate the luminance difference. By an iterative process, the continuous tone value is adjusted while compared with the perceived level of the halftoned patch. When the camera does not see any difference between the patches or a minimal difference, the luminance level of the con…