Designing visually rich, nearly random textures

Abstract

Camouflaging textures containing as in real life edges at all orientations, were designed by computer, then manually, for use in stereoscopic vision studies. In the manual procedure, the starting point is either a set of photographs (for instance, of barks) or a manually produced first-generation texture. Then patches are cut zigzagging and assembled into successive generations of textures. The absence of extended edges--straight or curved--and the local heterogeneity of the texture are important camouflaging factors, allowing curved surfaces to be covered with these textures without visible join. Small areas of a texture often suggest a scene, but when the areas are assembled, the suggestive power is lost, and the statistical properties of the texture then dominate. However, when symmetry is introduced (as in the Rorschach test), meaningful scenes emerge again.

Alternation Frequency Thresholds for Stereopsis as a Technique for Exploring Stereoscopic Difficulties

“…The four stereograms in this block (see figure 2) use textured grids that form curved surfaces in three dimensions. Such stereograms were designed to provide a flexible alternative for RDS (Ninio 1981, 2007). They contain contours at all orientations, a feature that may activate a stereoscopic pathway mediated by the oriented edge detectors in V1 and V2.…”

Phase haploscopy and characteristics of stereoscopic perception in strabismic patients

“…Вполне закономерным представляется то, что наибольшие трудности восприятия у всех пациентов возникали со случайно-точечными стереограммами [16,17]. Однако, несмотря на сложность интерпретации таких стереограмм, небольшая часть пациентов с патологией бинокулярного зрения могли воспринимать стереоэффект на частоте более 15 Гц.…”

Folded Sheet Versus Transparent Sheet Models for Human Symmetry Judgments

“…I also spent a fair amount of time producing symmetric patterns from random textures, trying to generate suggestive shapes that would extend as far as possible from the symmetry axis. [3]. In assembling strips of texture, I noticed a color effect: color differences between strips were attenuated when strips slightly differing in color were symmetrically juxtaposed [4], as though the existence of a symmetry axis was forcing the resemblance between the halves on the two sides of the axis.…”