Patent ID: 7477784
Filing Date: 2009-01-13
Classification: G06K

Abstract:
1. A process for processing an image containing codes comprising the steps of: using a processor or computer to perform the steps of: identifying code elements within the image; based on the location of the identified code elements, determining candidates for main directions of parallel lines within the image; identifying pairs of near perpendicular directions from the candidates; determining two main directions from the pairs of near perpendicular directions, the two main directions corresponding to the directions of lines forming a grid associated with the identified code elements; based on the two main directions, extracting features from the image; generating a homography matrix from the extracted features and from the two main directions; associating at least one of the identified code elements with one of the lines of the grid; and refining the homography matrix by attempting to minimize the distance between the identified code elements and the lines of the grid.