Patent US 5,768,451

A character recognition method is arranged to supplement an erroneously recognized character with a linguistic knowledge. In this method, the extraction of a candidate based on the search of a word dictionary occupies a large part of the operation. To speed up the extraction of a candidate word, therefore, the method is provided to search the dictionary by using a group of candidate characters or a dictionary header for processing an inflected form of a verb. Further, the present method is provided for calculating a word matching cost for improving an efficiency of modifying an erroneous recognition. The word search is done by using a "hybrid method" arranged of "candidate-character-driven word extraction" and "dictionary-driven word extraction". Moreover, the word-dictionary is arranged to have a header word composed of an inflectional ending of a verb and an auxiliary verb or a particle added to the tail of the inflectional ending. The present method attaches much importance to the difference of the matching cost about a character with a totally high confidence ratio than the difference of the matching cost about a character with a totally low confidence ratio.