Patent ID: 6917720
Filing Date: 2005-07-12
Classification: G06K

Abstract:
1. A process for recognition of reference marks for surveying of objects, each reference mark comprised of at least one survey character, at least one orientation character, and multiple encoded characters, comprising: forming a digital image comprised of pixels of a supposed or actual reference mark using electromagnetic waves in the optical or an adjacent wavelength range, automatically compensating for geometric distortions effecting the recognizability of the reference mark with the aid of the orientation character, determining the pixel coordinates of the center of the supposed or actual reference mark within their digital image, automatically compensating for radiometric disturbances, automatically compensating for disturbances due to partial covering, defining at least one quality measurement for the recognition of the reference mark, performing at least one reassessment check for positive recognition of an actual reference mark or for rejection of a supposed reference mark on the basis of said at least one quality measurement, and extracting from at least one of said encoded characters of an actual reference mark a characteristic character vector, which is supplied to a classification system, and that the reference marks being recognized are comprised of spatially separated survey, orientation and encoded characters.