An Omni-Font Gurmukhi to Shahmukhi Transliteration System

This paper describes a font independent Gurmukhi-to-Shahmukhi transliteration system. Even though Unicode is gaining popularity, but still there is lot of material in Punjabi, which is available in ASCII based fonts. A problem with ASCII fonts for Punjabi is there is no standardisation of mapping of Punjabi characters and a Gurmukhi character may be internally mapped to different keys in different Punjabi fonts. In fact there are more than 40 mapping tables in use for the commonly used Punjabi fonts. Thus there is an urgent need to convert the ASCII fonts to standard mapping, such as Unicode without any loss of information. Already many such font converters have been developed and are available online. But one limitation is that, all these systems need manual intervention in which the user has to know the name of source font. In the first stage, we have proposed a statistical model for automatic font detection and conversion into Unicode. Our system supports around 225 popular Gurmukhi font encodings. The ASCII to Unicode conversion accuracy of the system is 99.73% at word level with TOP1 font detection. The second stage is conversion of Gurmukhi to Shahmukhi at high accuracy. The proposed Gurmukhi to Shahmukhi transliteration system can transliterate any Gurmukhi text to Shahmukhi at more than 98.6% accuracy at word level.