3D Measurement of Shape Using Differential Stereo Vision Alborithm. Enlargement of Depth Range and Improvement of Measurement Accuracy.

In usual 3D measurement of shape by using stereo image, it is necesary to solve a correspondence problem which requires rather complicated image processing and high computational cost. Recently Ando developed the differential stereo vision system in which depth information can be derived from brightness values of image without solving the exact correspondence problem. However, this method has a weak point of narrow depth range in measurement. In this paper, we propose a method to solve a narrow depth range problem and to improve the accuracy of measurement for this method. Several examples of measurement are presented to demonstrate the effectiveness of the proposed method.