23 research outputs found
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The Perceptual Consequences of Curved Screens
Flat panels are by far the most common type of television screen. There are reasons, however, to believe that curved screens create a greater sense of immersion, reduce distracting reflections, and minimize some perceptual distortions that are commonplace with large televisions. To examine these possibilities, we calculated how curving the screen affects the field of view and the probability of seeing reflections of ambient lights. We find that screen curvature has a small beneficial effect on field of view and a large beneficial effect on the probability of seeing reflections. We also collected behavioral data to characterize perceptual distortions in various viewing configurations. We find that curved screens can in fact reduce problematic perceptual distortions on large screens, but that the benefit depends on the geometry of the projection on such screens
The role of transparency in da Vinci stereopsis
AbstractThe majority of natural scenes contains zones that are visible to one eye only. Past studies have shown that these monocular regions can be seen at a precise depth even though there are no binocular disparities that uniquely constrain their locations in depth. In the so-called da Vinci stereopsis configuration, the monocular region is a vertical line placed next to a binocular rectangular occluder. The opacity of the occluder has been mentioned to be a necessary condition to obtain da Vinci stereopsis. However, this opacity constraint has never been empirically tested. In the present study, we tested whether da Vinci stereopsis and perceptual transparency can interact using a classical da Vinci configuration in which the opacity of the occluder varied. We used two different monocular objects: a line and a disk. We found no effect of the opacity of the occluder on the perceived depth of the monocular object. A careful analysis of the distribution of perceived depth revealed that the monocular object was perceived at a depth that increased with the distance between the object and the occluder. The analysis of the skewness of the distributions was not consistent with a double fusion explanation, favoring an implication of occlusion geometry in da Vinci stereopsis. A simple model that includes the geometry of the scene could account for the results. In summary, the mechanism responsible to locate monocular regions in depth is not sensitive to the material properties of objects, suggesting that da Vinci stereopsis is solved at relatively early stages of disparity processing
Organisation of audio-visual three-dimensional space
Le terme stéréopsie renvoie à la sensation de profondeur qui est perçue lorsqu une scène est vue de manière binoculaire. Le système visuel s appuie sur les disparités horizontales entre les images projetées sur les yeux gauche et droit pour calculer une carte des différentes profondeurs présentes dans la scène visuelle. Il est communément admis que le système stéréoscopique est encapsulé et fortement contraint par les connexions neuronales qui s étendent des aires visuelles primaires (V1/V2) aux aires intégratives des voies dorsales et ventrales (V3, cortex temporal inférieur, MT). A travers quatre projets expérimentaux, nous avons étudié comment le système visuel utilise la disparité binoculaire pour calculer la profondeur des objets. Nous avons montré que le traitement de la disparité binoculaire peut être fortement influencé par d autres sources d information telles que l occlusion binoculaire ou le son. Plus précisément, nos résultats expérimentaux suggèrent que : (1) La stéréo de da Vinci est résolue par un mécanisme qui intègre des processus de stéréo classiques (double fusion), des contraintes géométriques (les objets monoculaires sont nécessairement cachés à un œil, par conséquent ils sont situés derrière le plan de l objet caché) et des connaissances à priori (une préférence pour les faibles disparités). (2) Le traitement du mouvement en profondeur peut être influencé par une information auditive : un son temporellement corrélé avec une cible définie par le mouvement stéréo peut améliorer significativement la recherche visuelle. Les détecteurs de mouvement stéréo sont optimalement adaptés pour détecter le mouvement 3D mais peu adaptés pour traiter le mouvement 2D. (3) Grouper la disparité binoculaire avec un signal auditif dans une dimension orthogonale (hauteur tonale) peut améliorer l acuité stéréo d approximativement 30%Stereopsis refers the perception of depth that arises when a scene is viewed binocularly. The visual system relies on the horizontal disparities between the images from the left and right eyes to compute a map of the different depth values present in the scene. It is usually thought that the stereoscopic system is encapsulated and highly constrained by the wiring of neurons from the primary visual areas (V1/V2) to higher integrative areas in the ventral and dorsal streams (V3, inferior temporal cortex, MT). Throughout four distinct experimental projects, we investigated how the visual system makes use of binocular disparity to compute the depth of objects. In summary, we show that the processing of binocular disparity can be substantially influenced by other types of information such as binocular occlusion or sound. In more details, our experimental results suggest that: (1) da Vinci stereopsis is solved by a mechanism that integrates classic stereoscopic processes (double fusion), geometrical constraints (monocular objects are necessarily hidden to one eye, therefore they are located behind the plane of the occluder) and prior information (a preference for small disparities). (2) The processing of motion-in-depth can be influenced by auditory information: a sound that is temporally correlated with a stereomotion defined target can substantially improve visual search. Stereomotion detectors are optimally suited to track 3D motion but poorly suited to process 2D motion. (3) Grouping binocular disparity with an orthogonal auditory signal (pitch) can increase stereoacuity by approximately 30%PARIS5-Bibliotheque electronique (751069902) / SudocSudocFranceF
Synchronized Audio-Visual Transients Drive Efficient Visual Search for Motion-in-Depth
In natural audio-visual environments, a change in depth is usually correlated with a change in loudness. In the present study, we investigated whether correlating changes in disparity and loudness would provide a functional advantage in binding disparity and sound amplitude in a visual search paradigm. To test this hypothesis, we used a method similar to that used by van der Burg et al. to show that non-spatial transient (square-wave) modulations of loudness can drastically improve spatial visual search for a correlated luminance modulation. We used dynamic random-dot stereogram displays to produce pure disparity modulations. Target and distractors were small disparity-defined squares (either 6 or 10 in total). Each square moved back and forth in depth in front of the background plane at different phases. The target’s depth modulation was synchronized with an amplitude-modulated auditory tone. Visual and auditory modulations were always congruent (both sine-wave or square-wave). In a speeded search task, five observers were asked to identify the target as quickly as possible. Results show a significant improvement in visual search times in the square-wave condition compared to the sine condition, suggesting that transient auditory information can efficiently drive visual search in the disparity domain. In a second experiment, participants performed the same task in the absence of sound and showed a clear set-size effect in both modulation conditions. In a third experiment, we correlated the sound with a distractor instead of the target. This produced longer search times, indicating that the correlation is not easily ignored
Organisation of audio-visual three-dimensional space
Le terme stéréopsie renvoie à la sensation de profondeur qui est perçue lorsqu’une scène est vue de manière binoculaire. Le système visuel s’appuie sur les disparités horizontales entre les images projetées sur les yeux gauche et droit pour calculer une carte des différentes profondeurs présentes dans la scène visuelle. Il est communément admis que le système stéréoscopique est encapsulé et fortement contraint par les connexions neuronales qui s’étendent des aires visuelles primaires (V1/V2) aux aires intégratives des voies dorsales et ventrales (V3, cortex temporal inférieur, MT). A travers quatre projets expérimentaux, nous avons étudié comment le système visuel utilise la disparité binoculaire pour calculer la profondeur des objets. Nous avons montré que le traitement de la disparité binoculaire peut être fortement influencé par d’autres sources d’information telles que l’occlusion binoculaire ou le son. Plus précisément, nos résultats expérimentaux suggèrent que : (1) La stéréo de da Vinci est résolue par un mécanisme qui intègre des processus de stéréo classiques (double fusion), des contraintes géométriques (les objets monoculaires sont nécessairement cachés à un œil, par conséquent ils sont situés derrière le plan de l’objet caché) et des connaissances à priori (une préférence pour les faibles disparités). (2) Le traitement du mouvement en profondeur peut être influencé par une information auditive : un son temporellement corrélé avec une cible définie par le mouvement stéréo peut améliorer significativement la recherche visuelle. Les détecteurs de mouvement stéréo sont optimalement adaptés pour détecter le mouvement 3D mais peu adaptés pour traiter le mouvement 2D. (3) Grouper la disparité binoculaire avec un signal auditif dans une dimension orthogonale (hauteur tonale) peut améliorer l’acuité stéréo d’approximativement 30%Stereopsis refers the perception of depth that arises when a scene is viewed binocularly. The visual system relies on the horizontal disparities between the images from the left and right eyes to compute a map of the different depth values present in the scene. It is usually thought that the stereoscopic system is encapsulated and highly constrained by the wiring of neurons from the primary visual areas (V1/V2) to higher integrative areas in the ventral and dorsal streams (V3, inferior temporal cortex, MT). Throughout four distinct experimental projects, we investigated how the visual system makes use of binocular disparity to compute the depth of objects. In summary, we show that the processing of binocular disparity can be substantially influenced by other types of information such as binocular occlusion or sound. In more details, our experimental results suggest that: (1) da Vinci stereopsis is solved by a mechanism that integrates classic stereoscopic processes (double fusion), geometrical constraints (monocular objects are necessarily hidden to one eye, therefore they are located behind the plane of the occluder) and prior information (a preference for small disparities). (2) The processing of motion-in-depth can be influenced by auditory information: a sound that is temporally correlated with a stereomotion defined target can substantially improve visual search. Stereomotion detectors are optimally suited to track 3D motion but poorly suited to process 2D motion. (3) Grouping binocular disparity with an orthogonal auditory signal (pitch) can increase stereoacuity by approximately 30
Organisation de l'espace audiovisuel tridimensionnel
Stereopsis refers the perception of depth that arises when a scene is viewed binocularly. The visual system relies on the horizontal disparities between the images from the left and right eyes to compute a map of the different depth values present in the scene. It is usually thought that the stereoscopic system is encapsulated and highly constrained by the wiring of neurons from the primary visual areas (V1/V2) to higher integrative areas in the ventral and dorsal streams (V3, inferior temporal cortex, MT). Throughout four distinct experimental projects, we investigated how the visual system makes use of binocular disparity to compute the depth of objects. In summary, we show that the processing of binocular disparity can be substantially influenced by other types of information such as binocular occlusion or sound. In more details, our experimental results suggest that: (1) da Vinci stereopsis is solved by a mechanism that integrates classic stereoscopic processes (double fusion), geometrical constraints (monocular objects are necessarily hidden to one eye, therefore they are located behind the plane of the occluder) and prior information (a preference for small disparities). (2) The processing of motion-in-depth can be influenced by auditory information: a sound that is temporally correlated with a stereomotion defined target can substantially improve visual search. Stereomotion detectors are optimally suited to track 3D motion but poorly suited to process 2D motion. (3) Grouping binocular disparity with an orthogonal auditory signal (pitch) can increase stereoacuity by approximately 30%Le terme stéréopsie renvoie à la sensation de profondeur qui est perçue lorsqu’une scène est vue de manière binoculaire. Le système visuel s’appuie sur les disparités horizontales entre les images projetées sur les yeux gauche et droit pour calculer une carte des différentes profondeurs présentes dans la scène visuelle. Il est communément admis que le système stéréoscopique est encapsulé et fortement contraint par les connexions neuronales qui s’étendent des aires visuelles primaires (V1/V2) aux aires intégratives des voies dorsales et ventrales (V3, cortex temporal inférieur, MT). A travers quatre projets expérimentaux, nous avons étudié comment le système visuel utilise la disparité binoculaire pour calculer la profondeur des objets. Nous avons montré que le traitement de la disparité binoculaire peut être fortement influencé par d’autres sources d’information telles que l’occlusion binoculaire ou le son. Plus précisément, nos résultats expérimentaux suggèrent que : (1) La stéréo de da Vinci est résolue par un mécanisme qui intègre des processus de stéréo classiques (double fusion), des contraintes géométriques (les objets monoculaires sont nécessairement cachés à un œil, par conséquent ils sont situés derrière le plan de l’objet caché) et des connaissances à priori (une préférence pour les faibles disparités). (2) Le traitement du mouvement en profondeur peut être influencé par une information auditive : un son temporellement corrélé avec une cible définie par le mouvement stéréo peut améliorer significativement la recherche visuelle. Les détecteurs de mouvement stéréo sont optimalement adaptés pour détecter le mouvement 3D mais peu adaptés pour traiter le mouvement 2D. (3) Grouper la disparité binoculaire avec un signal auditif dans une dimension orthogonale (hauteur tonale) peut améliorer l’acuité stéréo d’approximativement 30
Recommended from our members
The Perceptual Consequences of Curved Screens
Flat panels are by far the most common type of television screen. There are reasons, however, to believe that curved screens create a greater sense of immersion, reduce distracting reflections, and minimize some perceptual distortions that are commonplace with large televisions. To examine these possibilities, we calculated how curving the screen affects the field of view and the probability of seeing reflections of ambient lights. We find that screen curvature has a small beneficial effect on field of view and a large beneficial effect on the probability of seeing reflections. We also collected behavioral data to characterize perceptual distortions in various viewing configurations. We find that curved screens can in fact reduce problematic perceptual distortions on large screens, but that the benefit depends on the geometry of the projection on such screens