Takashi belt direction extracting equipment

摘要

PURPOSE: To precisely extract the protrusion line direction of a skin pattern picture through simple processing without setting a slit in every quantizing direction and the like in respect of a protrusion line extracting device required for the collation and the classification of a fingerprint and the collation of a palm print, etc. ;CONSTITUTION: First of all, in a gradient vector calculating means 12, a gradient vector at each point of a picture is calculated by calculating the horizontal derivative and the vertical derivative of the picture. In a distribution analyzing means 14, a direction to intersect the principal axis of the distribution of the gradient vector in a local area at right angles is obtained by using main component analysis, etc., and the obtained direction is determined to be the protrusion line direction in the local area, and is outputted.;COPYRIGHT: (C)1996,JPO