Devanagari Character Analysis

Devanagari script is complex in several ways. This has two-dimensional compositions of symbols viz. core characters in the middle strip, optional modifiers above and/or below core characters. Most of the characters are formed by curves, holes, and strokes. Apart from 13 vowels and 36 consonants characters which are called basic characters, there are compound characters in Devanagari script, which are formed by combining two or more basic characters. Theoretically there could be 46656 i.e. 36x36x36 triconsonantal conjunct characters. The shape of compound character is usually more complex than the constituent basic characters. The shape of these characters changes drastically with fonts. Separating the conjunct characters into its constituent

• Identifying the peculiarities or pattern of character occurrences.
• Classifying these characters in small manageable classes based on such properties which are invariant to the fonts.

By this proposed approach, the complexity in recognition of unknown character symbol is reduced to a much smaller number of possibilities resulting in development of a recognizer with increased accuracy and better response time.
10.2 Peculiarities in Devanagari from OCR perspective
There are various peculiarities inherent in Devanagari from OCR perspective. Once these peculiarities are identified and a classification scheme is created for each of the individual classes, it is expected to be more tolerant to noise and robust across multiple fonts and sizes. On observing frequently used symbol, various peculiarities which have been identified are as follows:
• Type of Bar in a character
• Number of places characters touch the header line
• Number of Water Bodies present in a character
• Number of Left Surface Cavities in a character
• Place of First Shirorekha Touching from left in a character
• Place of First Bar Touching Point from Bottom in a