Patent ID: 7263220

Claim:
A method of finding a color object in a digital image, comprising the following steps: (a) obtaining a search image that potentially includes the color object; (b) capturing a single model image including a model of the color object; (c) computing an edge Spatial Color Joint Probability Function (SCJPF) for the model image, wherein a model image edge SCJPF is a distribution of colors at color edges as well as spatial relationships between such colors in the model image, wherein a color edge is defined as a pixel whose color is different from its neighboring pixels according to a predetermined threshold; (d) generating a plurality of search windows each comprising a portion of the search image; (e) computing an edge SCJPF for each search window, wherein a search window SCJPF is a distribution of colors at color edges as well as spatial relationships between such colors in the search window; (f) assessing a first degree of similarity between the model image edge SCJPF and each of the search window edge SCJPFs; (g) computing a Spatial Color Joint Probability Function (SCJPF) for the model image, wherein a model image SCJPF is a distribution of colors as well as spatial relationships between such colors in the model image; (h) computing a SCJPF for each search window, wherein a search window SCJPF is a distribution of colors as well as spatial relationships between such colors in the search window; (i) assessing a second degree of similarity between the model image SCJPF and the search window SCJPF; and (j) designating a search window associated with (1) search window edge SCJPFs having a first degree of similarity to the model image edge SCJPFs which exceeds a first prescribed search threshold and (2) a search window SCJPF having a second degree of similarity to a model image SCJPF which exceeds a second prescribed search threshold as potentially containing the object being sought.