Recent evidence indicates that emotion enhances contrast thresholds in subsequent visual perception (Phelps, Ling, & Carrasco, 2006) and perceptual sensitivity for low-spatial frequency but not high-spatial frequency targets (Bocanegra & Zeelenberg, 2009b). However, these studies just report responses to various frequencies at a fixed contrast level or responses to various contrasts at a fixed ...

This report presents the work carried out for the image classification task in the course of the CLEF-IP 2011 competition. Based on the visual content, patent images are automatically classified into several drawing types, such as abstract drawings, tables, flow chart and graphs. For that purpose, a series of SVM classifiers, multi-modal fusion schemes and a variety of content-based low-level f...

Transient attention is the automatic and short-lasting preferential processing of an area in visual space initiated by sudden stimulation in the same vicinity. Transient attention enhances early visual processing in a variety of dimensions, increasing contrast sensitivity, spatial resolution, and acuity. A recent study established that the increase in contrast sensitivity is accompanied by an i...

Blur is an important attribute of human spatial vision, and sensitivity to blur has been the subject of considerable experimental research and theoretical modeling. Often, these models have invoked specialized concepts or mechanisms, such as intrinsic blur, multiple spatial frequency channels, or blur estimation units. In this paper, we review the several experimental studies of blur discrimina...

The objective of this research is to develop a system for language learning based on a ‘‘minimum’’ of pre-wired language-specific functionality, that is compatible with observations of perceptual and language capabilities in the human developmental trajectory. In the proposed system, meaning (in terms of descriptions of events and spatial relations) is extracted from video images based on detec...

The spatial filtering applied by the human visual system appears to be low pass for chromatic stimuli and band pass for luminance stimuli. Here we explore whether this observed difference in contrast sensitivity reflects a real difference in the components of chrominance and luminance in natural scenes. For this purpose a digital set of 29 hyperspectral images of natural scenes was acquired and...

PURPOSE The qCSF method is a novel procedure for rapid measurement of spatial contrast sensitivity functions (CSFs). It combines Bayesian adaptive inference with a trial-to-trial information gain strategy, to directly estimate four parameters defining the observer's CSF. In the present study, the suitability of the qCSF method for clinical application was examined. METHODS The qCSF method was...

PURPOSE To determine the effects of defocus-induced blur adaptation on human contrast sensitivity (CS) function. METHODS Defocused (+2 D) CS was measured for spatial frequencies between 0.5 and 12 cycles per degree (cpd) before and after adaptation to +2 D blur in six subjects with normal vision. During the 30-minute adaptation period with +2 D lens, subjects were exposed to a succession of s...