COMPARISON OF PATTERNS

摘要

A first visual image or other pattern (A) is represented by a first ordered set of elements (xi) each having a value and a second pattern (B) is a represented by a second ordered set of element (ui) each having a value. Iteratively, a comparison is made by: (i) selecting a plurality of elements from the first ordered set ; (ii) for each selected element of the first ordered set, selecting an element from the second ordered set, such that the selected elements of the second ordered set have, within the second ordered set, a set of positional relationships relative to each other that is the same as, or a transformation of, the set of positional relationships that the selected plurality of elements of the first ordered set have relative to each other; (iii) selecting a random shift value ( ); and (iv) determining whether the selected elements meet the match criterion that the value of each of the selected elements of the first ordered set differs from the value of the correspondingly positioned selected element of the second ordered set by an amount that is equal to, or within a set margin of, and in the same sense as, said shift value. In the event of a match, a similarity score (SAB) is updated. Alternatively, or in addition, the shift amount in the event of a match is recorded and, at the conclusion of the iteration, a single representative shift value is estimated from said recorded shift value.