CHARACTER-FEATURE EXTRACTION DEVICE

A feature recognition method and apparatus is described where in one embodiment the digitized two-dimensional pattern or image usually of a character to be recognized is subjected first to conversion into a vector. The vector subsequently undergoes propagation and stopping operations subject to various tests so as to generate a list of unique features about the pattern being identified. Thusly, identified features are compared mathematically to a previously created feature library until a match is found. In an alternative embodiment, to increase the speed of three-dimensional, feature-extraction processing of character patterns the vector-extraction positions on a pattern are converted into flags and accommodated in a corresponding motion-flag memory. Flag values in the motion-flag memory and a stopping-flag memory are read sequentially after propagation processing, and it is determined whether there are flag values representing the existence of vectors in the flag values in the above addresses of other flag memories and addresses adjoining thereto. The flag values in corresponding addresses in a self-moving flag memory are reset, and at the same time, the flags are set in corresponding addresses in the stopping-flag memory relative to vectors with the same direction, if there are vector flag values in the corresponding addresses. The flag values in each stopping-flag memory and each motion-flag memory are converted into vector values via determination processing after propagation processing, and are output as three-dimensional features.