The perception of 3D shape from texture

我们的眼睛呈现给我们一个三维的世界，然而通过眼睛进入的信息不是三维的。 位于每个眼球后部的视网膜实际上是一个二维的感受器细胞片。 从世界上三维物体反射或发射的光实际上被转换为视网膜上的二维图案。 那么，我们如何在这些二维模式的基础上感知深度的第三维呢？ 这是视觉感知领域的一个经典问题，几十年的研究已经产生了一系列深度线索，我们的视觉系统使用这些线索来“重建”第三维。 我们仍在试图理解的是，视觉系统究竟是如何利用每一个线索来完成这一感知壮举的？在国家科学基金会的支持下，托德博士将仔细研究一种称为“光学纹理”的视觉深度线索的性质。 为了说明这一点，想象一下仔细观察一个有酒窝的高尔夫球。 酒窝的视觉外观被球的曲率扭曲了，我们的视觉系统可以利用这种扭曲作为关于球在所有三个维度上的圆度的信息来源。 托德博士已经开发了一个计算模型的视觉系统如何计算的基础上，其纹理图案的对象的形状，本研究项目将调查他的模型是否是一个准确的表征人类视觉系统如何使用光学纹理作为深度线索。 将进行实验以精确测试人类参与者如何使用光学纹理，并将这些实验的结果与模型的预测进行比较。 除了提高我们对人类视觉感知的认识外，这些结果还可以为机器视觉和计算机图形学中更强大和有效的算法的设计提供信息，以及为盲人提供更多功能的假肢设备。

Our eyes present to us a world in three dimensions, and yet the information coming in through the eyes is not three dimensional. The retina that sits at the back of each eyeball is effectively a two-dimensional sheet of receptor cells. The light that is reflected or emitted from three-dimensional objects in the world is actually transduced as two-dimensional patterns on the retina. So how do we perceive the third dimension of depth on the basis of these two-dimensional patterns? This is a classic question in the area of visual perception, and many decades of research have resulted in a list of depth cues that our visual systems use to "reconstruct" the third dimension. What we are still trying to understand is, precisely how does the visual system utilize each cue to perform this feat of perception?With support of the National Science Foundation, Dr. Todd will closely examine the nature of one visual depth cue called "optical texture". To illustrate, imagine looking closely at a dimpled golf ball. The visual appearance of the dimples is warped by the curvature of the ball, and our visual systems can use this warping as a source of information about its roundness in all three dimensions. Dr. Todd has developed a computational model of how the visual system calculates the shape of an object based on its textural patterning, and the present research project will investigate whether his model is an accurate characterization of how the human visual system uses optical texture as a depth cue. Experiments will be conducted to precisely test how human participants use optical texture, and the results from these experiments will be compared against the predictions of the model. Besides advancing our knowledge of human visual perception, these results may inform the design of more robust and effective algorithms in machine vision and computer graphics, and more functional prosthetic devices for the blind.