Binary digital image feature extracting process

摘要

A binary digital image feature extracting process whereby a number of elementary portions of predetermined shape are defined in a binary digital matrix; in each elementary portion, a number of analysis directions are defined at a predetermined angle in relation to the edges of the elementary portion; a number of paths are defined, each formed by an orderly set of pixels arranged at least approximately parallel to a respective analysis direction; for each path, the pixels presenting a predetermined characteristic definable by one or more whole numbers are determined; the numbers are converted by a nonlinear function to calculate a number of partial scores which are then grouped to give an overall score for each path; and the overall scores of the various paths are grouped according to the analysis direction to calculate a directional feature for each analysis direction.