Optical image encoding and comparing using scan autocorrelation

摘要

A method for encoding shape and pattern information from the image (20) of an electronic camera (10). The image is converted into a discrete array of values (30), and the values in the cross sections of the array are sampled (circuit 40), marked for transitions (circuit 50), and the transition markers are then autocorrelated by circuit 60 to form an autocorrelation function for each cross section. The autocorrelation functions corresponding to each cross section are then combined by circuit 70 into a global summary function, which provides a quantitative measure of the information contained in the image. The global summary functions which are derived from images may be used to judge their similarity or otherwise compare and classify them.