Abstract

An iteratively designed correlation filter Is used in a coherent optical system to perform recognition of targets independent of their position, rotation, or intensity. A full 3-D correlation operation is obtained by rotating the filter in the Fourier plane. The filter is designed so that the target image produces a constant-intensity response in the output as the filter is rotated, while other objects produce specklelike intensity variations. Therefore, detection consists of locating those pixels in the correlation plane which remain constant. This process requires only two data buffers, one to accumulate the intensity of each frame and one to accumulate the intensity-squared.

© 1986 Optical Society of America