Showing papers on "Intelligent word recognition published in 1978"

A Multifont Word Recognition System for Postal Address Reading

Abstract: This paper describes the basic design principles of a multifont word recognition system developed for postal address reading. Of the three main subsystems, image preprocessing, single character recognition, and contextual postprocessing, the last two will be considered in detail. A multiple-channel/multiple-choice approach is taken in designing the overall system. The character images produced by the image preprocessing subsystem are fed into three parallel single character recognition (SCR) channels. Each channel classifies the raster image according to one of the three character types: capital letter, small letter, or numeral. A second degree polynomial classifier is required in order to satisfy the multifont requirements of address reading. Each SCR channel outputs a rank-ordered list of potential character meanings for the character type being processed and a channel-specific figure of confidence. This figure of confidence serves a twofold purpose. First, it is used to determine the number of alternatives in the rank-ordered list, and secondly, it is used by the subsequent contextual postprocessor in calculating a word-specific discriminant function designed to discriminate between four different kinds of words: numeric, all upper case, all lower case, and lower case with upper case initial. Based on this discriminant function for every character position, only one channel output is passed on to-the word recognition system. From the list of alternatives for each character position, a set of alternative words can be constructed which, with a high probability, contains the correct word.

Recognition of Spoken Words and Phrases in Multitalker Environment Using Syntactic Methods

Abstract: We describe a method of recognizing isolated words and phrases from a given vocabulary spoken by any member in a given group of speakers, the identity of the speaker being unknown to the system. The word utterance is divided into 20-30 nearly equal frames, frame boundaries being aligned with glottal pulses for voiced speech. A constant number of pitch periods are included in each frame. Statistical decision rules are used to determine the phoneme in each frame. Using the string of phonemes from all the frames of the utterance, a word decision is obtained using (phonological) syntactic rules. The syntactic rules used here are of 2 types, namely, 1) those obtained from the theory of word construction from phonemes in English as applied to our vocabulary, 2) those used to correct possible errors in phonemic decisions obtained earlier based on the decisions of neighboring segments. In our experiment, the vocabulary had 40 words, consisting of many pairs of words which are phonemically close to each other. The number of speakers was 6. The identity of the speaker is not known to the system. In testing 400 words utterances, the recognition rate was about 80 percent for phonemes (for 11 phonemes) but the word recognition was 98.1 percent correct. Phonological-syntactic rules played an important role in upgrading the word recognition rate over the phoneme recognition rate.