Patent ID: 7113652

Claim:
A system for utilizing a normalized gray scale pattern find within a machine vision system, the system comprising: (a) means for correlating a reference image having a first spatial resolution having no particular degree of rotation within a first search region of interest of an acquired image to find a potential match location; (b) means for correlating a rotated reference image having the first spatial resolution at a particular degree of rotation within the first search region of interest to find a potential match location; (c) means for selecting the potential match location and the particular degree of rotation corresponding to the highest correlation value; (d) means for increasing the spatial resolution of the reference image at the particular degree of rotation to generate a new reference image and correlating the new reference image within a second search region of interest centered at the selected potential match location; (e) means for selecting an updated potential match location corresponding to a location having the highest correlation value that is completely within the search region of interest; (f) means for repeating steps (d) and (e) for all available resolutions for the reference image; and (g) means for selecting a match location and orientation of a reference image within the acquired image corresponding to the location having the highest correlation value.