Zheng and Tsuji 1990 : The authors explore a new intrinsic property of dynamic vision, shape from motion, and they argue its superiority over motion from shape change for a class of motion. Based on the concept of anorthoscopic perception, the authors show how a two-dimensional dynamic projection, which contains the major portion of spatial and temporal information of dynamic 3-D scenes, is obtained from consecutive 1-D images through a slit, when the relative motion between the viewer and scenes is known. The slit should be nonparallel to the optical flow in an image. Analyzing the projection reduces the redundant processing of shape. It can facilitate dynamic object recognition or 3-D structure acquisition for stable motion of objects or camera.