A Fast Subpixel Locating Algorithm with Shielding Case

Aimed at the image locating problem with shielding case, this paper analysis the shortage of general pattern match algorithm then present a fast subpixel locating algorithm based on characteristic edges detect of shielding case. First, it uses binarization and blob analysis method to remove the small particles; Next, it performs a Laplacian transform to get the edge image; And then finds the line segment sets and filter with the size information of the case to get the characteristic edges, And then use Zernike orthogonal moment to get subpixel edges; Finally deduces the center and rotate angle with the characteristic edges. The result shows the locating speed and the accuracy of the algorithm is well and meets the practical application. The algorithm also has strong robust.