Retinal speed gradients and the perception of surface slant.
نویسندگان
چکیده
Previous work has demonstrated a difference in human sensitivity to compressive and shearing speed gradients. This raises the possibility that the ability to estimate the slant of a surface may vary with its direction of tilt. No such variance was found here, which may indicate that slant estimation depends upon deformation rather than upon compression or shear.
منابع مشابه
Speed gradients and the perception of surface slant: Analysis is two-dimensional not one-dimensional
Motion parallax provides cues to the three-dimensional layout of a viewed scene and, in particular, to surface tilt and slant. For example, as a textured surface, inclined around a horizontal axis, translates horizontally relative to an observer's view point, then, in the absence of head and eye movements, the observer's retinal flow will contain a one-dimensional (1D) vertical speed gradient. ...
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In previous work [Meese et al. (1995). Vision Research, 35, 2879-2888)] we showed that one-dimensional (1D) speed gradients are sufficient to produce a compelling impression of surface slant. Summing a 1D vertical shearing gradient or, less intuitively, a 1D horizontal shearing gradient with a random field of horizontally translating dots produces perceived slant about a horizontal axis. Simila...
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عنوان ژورنال:
- Vision research
دوره 32 3 شماره
صفحات -
تاریخ انتشار 1992