Feature extraction technique for use in a pattern recognition system

摘要

A method is provided for forming feature vectors representing the pixels contained in a pattern desired to be recognized, and reference patterns. One part of the feature vector is representative of the pixels contained in the pattern itself, while not requiring a very large feature vector which exactly defines each pixel of the pattern. One embodiment of this invention provides that another part of the feature vector, consisting of one or more bytes of the feature vector, defines the aspect ratio of the pattern. In one embodiment, each byte of the feature vector representing the pixels contained in the character represents the relative ratio of black pixels to total pixels in a specific area of the character; other functions relating input matrix and output feature vector information can be used. In one embodiment of this invention, those areas of the character which are defined by the feature vector together cover the entire character, providing a feature vector describing what might loosely be thought as a "blurred" version of the pattern.