Patent ID: 8121357
Filing Date: 2012-02-21
Classification: G06K

Abstract:
1. A coefficient determining method for determining a coefficient used in a calculation for extracting a judgment feature of a pattern; wherein a computing device of a calculator executes a method comprising: extracting feature information from each of a plurality of patterns stored in advance for every class in a storage device; calculating an interclass covariance matrix and an intraclass covariance matrix on a kernel space using the extracted feature information; calculating an optimum vector which maximizes a ratio of the interclass covariance/intraclass covariance; calculating an approximate vector which minimizes a square norm with the optimum vector; deriving a conversion formula for converting the feature information to a judgment feature of the pattern using the calculated approximate vector; storing the coefficient in the derived conversion formula as a coefficient to be substituted to the conversion formula for extracting the judgment feature of the pattern when carrying out pattern check; and recalculating the interclass covariance matrix using the judgment feature obtained by the conversion formula; wherein the computing device repeatedly calculates an optimum vector, calculates an approximate vector, derives a conversion formula, stores the coefficient in the derived conversion formula, and recalculates the interclass covariance matrix, by using the recalculated interclass covariance matrix until reaching a maximum iteration count, which is the number of judgment features.