A theory of eecient stereo coding 2] predicts that, in a natural visual environment, where the ocular correlation of the input depends on stimulus orientations, the striate cortical cells are more likely binocular when selective to horizontal rather than vertical orientations. A psychophysical experiment was designed to test this prediction. The interocular transfers of simultaneous orientation...

Differences in the low-level image statistics of environmental scenes contain sufficient information to characterize different types of environments. Briefly displayed visual scenes can be strongly influenced by adaptation to the statistical characteristics of the prevailing visual input. We have previously reported an apparent processing boundary between basic categories of natural and man-mad...

To investigate changes in spatial orientation ability and walking performance following space flight, 7 astronaut subjects were asked preand post-flight to perform a goal directed locomotion paradigm which consisted of walking a triangular path with and without vision. This new paradigm, involving inputs from different sensory systems, allows quantification of several critical parameters, like ...

A fixed base digital stereo-vision system is a powerful tool for positioning objects in 3-dimensions without control in object space. It can be integrated in a vehicle together with GPS and inertial systems to collect spatial information while driving at highway speeds. In this paper we discuss the integrated calibration of the stereo-vision system using a simultaneous, constrained adjustment o...

To clarify the factors causing oscillopsia, we investigated head movement, gaze stability, and perception under various situations. High-frequency head movements, whether they were horizontal rotations or passively induced vertical oscillations, produced blurred vision and gaze fluctuations in patients with labyrinthine loss. However, this sensation differed from the oscillopsia perceived durin...

Perceptual processes, in computer or biological vision, require the computation of “maps” of quantitative values. The image itself is a “retinotopic map”: for each pixel of the image there is a value corresponding to the image intensity at this location. This is a vectorial value for color images. A step further, in early-vision, the retinal image contrast is computed at each location, allowing...

The administrative burden the government puts on citizens is substantial, whereas, generally speaking, service levels are low and a ‘customer’ orientation is lacking. There is a growing understanding that e-government can play an important role in tackling these issues by better exchange of information and electronic availability. This paper reports on the development and evaluation of an e-gov...

A novel distinguished region detector, complementary to existing approaches like Harris-corner detectors, Difference of Gaussian detectors (DoG) or Maximally Stable Extremal Regions (MSER) is proposed. The basic idea is to find distinguished regions by clusters of interest points. In order to determine the number of clusters we use the concept of maximal stableness across scale. Therefore, the ...

The articles in this special section, by offering ethnographically grounded reflections on diverse strains of economic activism, begin to articulate a non-capitalocentric political ecology that we think can help scholaractivists politicize, reimagine, and recreate socio-ecological relations. In this introductory article, we offer a useful vision of how scholar-activists can engage with and supp...

According to the prevailing view, the elements of early visual processing are characterized by simple geometric properties such as length, orientation, and curvature. We demonstrate in this chapter that this view must be revised—the elements of early vision need not be geometrically simple. Instead, they can be characterized in terms of environmental relevance, computational architecture, and p...