Methods and apparatus for zooming during capture and reproduction of 3-dimensional images

Abstract

In the capture and display of three dimensional images, techniques are provided for controlling the amount of disparity between left and right images used to create a three dimensional representation to permit three dimensional perception which would otherwise be lost as disparity increased beyond psychological and physiological limits. Both mechanical and electronic means for controlling disparity are shown. Techniques are disclosed for creating three dimensional animations which utilize disparity control for adjusting the perceived depth of an object vis-a-vis a neutral plane. When zooming in on an object with a stereo camera pair, the shift in focal length accompanying the zoom is accompanied by a simultaneous shift in disparity so that the stereo effect is not lost when a target object is very close, a moderate distance, or very far from the cameras. Camera separation is changed as a function of target distance to maintain a fixed fraction of the target distance as a default. The default can be overridden by adjusting disparity independently of the default. Personal discomfort which often accompanies viewing of stereo images is reduced by maintaining camera axes parallel so that unnecessary vertical shift is minimized or eliminated.