Searched for: subject:"perception"
(1 - 13 of 13)
document
Van Doorn, A.J. (author), De Ridder, H. (author), Koenderink, J.J. (author)
Pictorial relief depends strongly on “cues” in the image. For isoluminant renderings some cues are missing, namely all information that is related to luminance contrast (e.g., shading, atmospheric perspective). It has been suggested that spatial discrimination and especially pictorial space suffer badly in isoluminant conditions. We have...
conference paper 2005
document
Wijntjes, M.W.A. (author), Volcic, R. (author), Pont, S.C. (author), Koenderink, J.J. (author), Kappers, M.L. (author)
We studied the influence of haptics on visual perception of three-dimensional shape. Observers were shown pictures of an oblate spheroid in two different orientations. A gauge-figure task was used to measure their perception of the global shape. In the first two sessions only vision was used. The results showed that observers made large errors...
journal article 2009
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Richards, W. (author), Koenderink, J.J. (author), Van Doorn, A. (author)
Unlike the Metelli monochrome transparencies, when overlays and their backgrounds have chromatic content, the inferred surface colors may not always be physically realizable, and are in some sense “imaginary.” In these cases, the inferred chromatic transmittance or reflectance of the overlay lies outside the RGB spectral boundaries. Using the...
journal article 2009
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Norman, J.F. (author), Kappers, A.M.L. (author), Beers, A.M. (author), Scott, A.K. (author), Norman, H.F. (author), Koenderink, J.J. (author)
Two experiments evaluated the ability of older and younger adults to perceive the three-dimensional (3D) shape of object surfaces from active touch (haptics). The ages of the older adults ranged from 64 to 84 years, while those of the younger adults ranged from 18 to 27 years. In Experiment 1, the participants haptically judged the shape of...
journal article 2010
document
Koenderink, J. (author)
The egg-rolling behavior of the graylag goose is an often quoted example of a fixed-action pattern. The bird will even attempt to roll a brick back to its nest! Despite excellent visual acuity it apparently "takes a brick for an egg." Evolution optimizes utility, not veridicality. Yet textbooks take it for a fact that human vision evolved so as...
conference paper 2011
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Wagemans, J. (author), Van Doorn, A.J. (author), Koenderink, J.J. (author)
We propose a novel method to probe the depth structure of the pictorial space evoked by paintings. The method involves an exocentric pointing paradigm that allows one to find the slope of the geodesic connection between any pair of points in pictorial space. Since the locations of the points in the picture plane are known, this immediately...
journal article 2011
document
Van Doorn, A. (author), Koenderink, J. (author), Wagemans, J. (author)
We address the topic of “pictorial depth” in cases of pictures that are unlike photographic renderings. The most basic measure of “depth” is no doubt that of depth order. We establish depth order through the pairwise depth-comparison method, involving all pairs from a set of 49 fiducial points. The pictorial space for this study was evoked by a...
journal article 2011
document
Wagemans, J. (author), Van Doorn, A.J. (author), Koenderink, J.J. (author)
In the physical environment familiar size is an effective depth cue because the distance from the eye to an object equals the ratio of its physical size to its angular extent in the visual field. Such simple geometrical relations do not apply to pictorial space, since the eye itself is not in pictorial space, and consequently the notion ...
journal article 2011
document
Van Doorn, A.J. (author), Wagemans, J. (author), De Ridder, H. (author), Koenderink, J.J. (author)
A "picture" is a at object covered with pigments in a certain pattern. Human observers, when looking "into" a picture (photograph, painting, drawing, . . . say) often report to experience a three dimensional "pictorial space." This space is a mental entity, apparently triggered by so called pictorial cues. The latter are sub-structures of color...
conference paper 2011
document
Pont, S.C. (author), Van Doorn, A.J. (author), Te Pas, S.F. (author), Wijntjes, M.W.A. (author), Koenderink, J.J. (author)
We present a novel setup in which real objects made of two different materials can be mixed optically in a linearly weighted manner. We conducted a psychophysical experiment in which observers rated optical mixtures of the three combinations of glossy, matte, and velvety green birds. The observers rated the materials on four scales: matte-glossy...
conference paper 2012
document
Pont, S.C. (author), Koenderink, J.J. (author), Van Doorn, A.J. (author), Wijntjes, M.W.A. (author), Te Pas, S.F. (author)
We present a novel setup in which real objects made of different materials can be mixed optically. For the materials we chose mutually very different materials, which we assume to represent canonical modes. The appearance of 3D objects consisting of any material can be described as linear superposition of 3D objects of different canonical...
conference paper 2012
document
Van Doorn, A.J. (author), Koenderink, J.J. (author), Leyssen, M.H.R. (author), Wagemans, J. (author)
We study the effect of stylistic differences on the nature of pictorial spaces as they appear to an observer when looking into a picture. Four pictures chosen from diverse styles of depiction were studied by 2 different methods. Each method addresses pictorial depth but draws on a different bouquet of depth cues. We find that the depth...
journal article 2012
document
Koenderink, J.J. (author), Van Doorn, A.J. (author)
“Pictorial space” is the mental structure that appears to be the scaffold for the visual awareness when looking “into” (as opposed to “at”) a picture. Its structure differs from the “visual space” that is the scaffold for the visual awareness when looking into the scene in front of the observer. The structure of pictorial space has been probed...
journal article 2012
Searched for: subject:"perception"
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