Kerzel D, Hecht H
Universität Bielefeld.
Z Exp Psychol. 1997;44(3):394-430.
Pictures often do not appear distorted even when viewed at oblique angles. Three hypotheses have been put forth to explain this robustness of virtual space toward affine transformations. First, array specificity holds that the perception of depicted space is fully specified by the information available at the point of observation. Second, the notion of a compensatory mechanism involves an unconscious recreation of the scene according to the original viewpoint. Third, the indiscrimination hypothesis denies the ability of the visual system to resolve or detect affine transformations up to a certain degree. Three experiments were conducted to investigate these claims. Using a double projection technique devised by Cutting (1987), Experiment I showed that observers are able to discriminate and compensate, to some degree, for affine transformations if information about the projection surface is available. However, observers relied on relative image velocities rather than reconstructing the object. In Experiment 2 additional observer motion was simulated. In single and double projection trials that required more difficult judgments of object rotation, compensation was poor and observers seemed to rely on local cues. Finally, real and simulated rotation of the projection surface revealed that observers are able to compensate for only one primary projection surface slant. The results reject the indiscrimination hypothesis and support the notion of array specificity.
即使从倾斜角度观看，图片通常也不会出现失真。已经提出了三种假设来解释虚拟空间对仿射变换的这种稳健性。第一，阵列特异性认为，所描绘空间的感知完全由观察点处可用的信息确定。第二，补偿机制的概念涉及根据原始视点对场景进行无意识的重新构建。第三，无差别假设否认视觉系统在一定程度上分辨或检测仿射变换的能力。进行了三项实验来研究这些说法。使用由Cutting（1987）设计的双投影技术，实验1表明，如果有关于投影表面的信息，观察者能够在一定程度上辨别和补偿仿射变换。然而，观察者依赖于相对图像速度而不是重建物体。在实验2中，模拟了额外的观察者运动。在需要对物体旋转进行更困难判断的单投影和双投影试验中，补偿效果很差，观察者似乎依赖于局部线索。最后，投影表面的实际旋转和模拟旋转表明，观察者只能补偿一个主投影表面的倾斜。结果否定了无差别假设，并支持了阵列特异性的概念。
