Patent ID: 7805015

Claim:
A computer implemented method for identifying interest points, the computer implemented method comprising: receiving a set of digital images and a set of threshold values, wherein the set of digital images includes a set of digital frames; calculating a number of directional values for each pixel in a set of pixels within each digital frame in the set of digital frames to form a number of directional values, wherein the number of directional values calculated are at least eight directional values and wherein the at least eight directional values comprise eight different directions of each pixel; identifying, by a processing unit, a set of interest points within each digital frame in the set of digital frames using the set of threshold values and the number of directional values, wherein each interest point in the set of interest points is identified by a pixel within the set of pixels comprising two directional values of the number of directional values that are within a first threshold value from the set of threshold values and five directional values of the number of directional values that are within a second threshold value from the set of threshold values and wherein the first threshold value is a range of directional values that is closer to a value of the pixel than a range of directional values of the second threshold value; and determining a set of characteristics for the set of interest points.