Patent ID: 8081818

Claim:
A computer program product, encoded on a non-transitory computer-readable medium, operable to cause a computer to perform operations comprising: defining a search region in an image, wherein each pixel in the search region has a coordinate value indicating a location in the image; computing a weighted coordinate value for each pixel within the search region by multiplying a value of each respective pixel by the coordinate value of the respective pixel; calculating initial values of parameters defining a shape, the shape enclosing an inner group of pixels in the search region, the initial values defining the shape to cover a region in the search region identified as possibly containing a feature, wherein the initial values of the parameters defining the shape are calculated using the weighted coordinate value of each pixel in the search region; computing an inner value using values of the pixels in the inner group of pixels; computing an outer value using values of pixels in an outer group of pixels in the image, the outer group of pixels being outside the shape; and varying the parameters of the shape to change the inner value relative to the outer value.