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	Provedor de dados BJMBR (2) Autor Zana,Y. (2) Cavalcanti,A.C.G.T. (1) Cesar Jr.,R.M. (1) Mena-Chalco,J.P. (1) Palavra-chave Cartesian and polar coordinates (1) Cognitive processes (1) Computational modeling (1) Contrast sensitivity functions (1) Face processing (1) Radial and angular gratings (1) Visual perception (1) Mais... Tipo do documento Info:eu-repo/semantics/article (2) Ano 2009 (1) 2004 (1) País Brazil (2) Idioma Inglês (2)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 2 Primeira ... 1 ... Última Contrast sensitivity to angular frequency gratings is not higher than to Cartesian gratings BJMBR Zana,Y.; Cavalcanti,A.C.G.T.. When contrast sensitivity functions to Cartesian and angular gratings were compared in previous studies the peak sensitivity to angular stimuli was reported to be 0.21 log units higher. In experiments carried out to repeat this result, we used the same two-alternative forced-choice paradigm, but improved experimental control and precision by increasing contrast resolution from 8 to 12 bits, increasing the screen refresh rate from 30 Hz interlaced to 85 Hz non-interlaced, linearizing the voltage-luminance relation, modulating luminance in frequencies that minimize pixel aliasing, and improving control of the subject's exposure to the stimuli. The contrast sensitivity functions to Cartesian and angular gratings were similar in form and peak sensitivity (2.4... Tipo: Info:eu-repo/semantics/article Palavras-chave: Contrast sensitivity functions; Cartesian and polar coordinates; Radial and angular gratings. Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000200010 A novel polar-based human face recognition computational model BJMBR Zana,Y.; Mena-Chalco,J.P.; Cesar Jr.,R.M.. Motivated by a recently proposed biologically inspired face recognition approach, we investigated the relation between human behavior and a computational model based on Fourier-Bessel (FB) spatial patterns. We measured human recognition performance of FB filtered face images using an 8-alternative forced-choice method. Test stimuli were generated by converting the images from the spatial to the FB domain, filtering the resulting coefficients with a band-pass filter, and finally taking the inverse FB transformation of the filtered coefficients. The performance of the computational models was tested using a simulation of the psychophysical experiment. In the FB model, face images were first filtered by simulated V1- type neurons and later analyzed globally... Tipo: Info:eu-repo/semantics/article Palavras-chave: Face processing; Visual perception; Cognitive processes; Computational modeling. Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000700008 Registros recuperados: 2 Primeira ... 1 ... Última

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