International Journal of Computer and h~formation Sciences, Vol. 7, No. 3, 1978 CHITRA: Cognitive Handprinted Input- Trained Recursively Analyzing System for Recognition of Alphanumeric Characters 1 Belur V. Dasarathy 2 and K. P. Bharath Kumar ~ Received June 1975; revised January 1977 A novel system for recognition of handprinted alphanumeric characters has been developed and tested. The system can be employed for recognition of either the alphabet or the numeral by contextually switching on to the corresponding branch of the recognition algorithm. The two major com- ponents of the system are the multistage feature extractor and the decision logic tree-type catagorizer. The importance of "good" features over sophisti- cation in the classification procedures was recognized, and the feature extractor is designed to extract features based on a variety of topological, morphological and similar properties. An information feedback path is provided between the decision logic and the feature extractor units to facilitate an interleaved or recursive mode of operation. This ensures that only those features essential to the recognition of a particular sample are extracted each time. Test implementation has demonstrated the reliability of the system in recognizing a variety of handprinted alphanumeric characters with close to 100 ~ accuracy. KEY WORDS: Character recognition; handprinted alphanumerics; deci- sion tree logic; multistage interleaved feature extraction-categorization approach. i Most of this work was carried out at the School of Automation, Indian Institute of Science, Bangalore, India. M & S Computing, Inc., P. O. Box 5183, Huntsville, Alabama. 3 Department of Electrical Engineering, University of Hawaii, Honolulu, Hawaii. 253 0091-7036/78/0900-0253505.00/0 9 1978Plenum Publishing Corporation