Bilingual Spell Checker for Punjabi and English with support for additional dictionaries
A language senstive Punjabi/English spell checker has been provided in Akhar. Akhar can automatically detects the language and invokes the respective spell checker. The Unicode compliant Punjabi spellchecker is font indepent and can work on any of the popular Punjabi fonts such as AnanpurSahib, AmritLipi, Jasmine, Punjabi, Satluj etc. This removes the constraint on the user to type the text in predefined fonts only.

A snap shot of Punjabi Spell checker

1. Unicode/ISCII Compliant : For keeping pace with the time, Punjabi Spell checker works on ISCII and Unicode encoded Punjabi files as well as text encoded in the common file formats such as DOC, RTF and HTML.
2. Support for popular Punjabi fonts and keyboards: The spell checker has been designed to provide support for Punjabi text encoded in any of the popular Punjabi fonts such as AnanpurSahib, AmritLipi, Jasmine, Punjabi, Satluj etc. More than one hundred Punjabi fonts and thirty two Punjabi keyboard layouts have been supported. This removes the constraint on the user to type the text in predefined fonts only. The inbuilt font converter automatically converts the text to be spell checked to one of the standard fonts in which the dictionary has been encoded.
3. Provision for additional dictionaries: The main dictionary for spell checker has around 1.50 lakh words in its database. The main dictionary contains most common words, but it might not include proper names, technical terms, acronyms, words from Gurbani and so on. To prevent the spelling checker from questioning such words, the Spell Checker provides a built-in custom dictionary and in addition the user can create their own custom dictionaries such as separate custom dictionaries for legal or medical terms. In addition, a dictionary of all the words occurring in Guru Granth Sahib has also been developed and can be be used along with the main dictionary to check for texts quoted from Gurbani.
4. Powerful Suggestion List: The real power and utility of a spell checker depends on the suggestion list provided by the spell checker. For designing an efficient spellchecker a detailed error pattern analysis of Punjabi has been carried out. It included analysis of various types of errors (insertion, deletion, transposition, substitution, run-on, split word error) positional analysis, word length effects, phonetic errors, first position error analysis, keyboard effects etc. A detailed analysis based on the carefully collected spelling error patterns has been done on around 20,000 misspellings from more than 12 lakh words. To collect the candidates of suggestion list, a reverse minimum edit distance is used where a candidate set of words is produced by first generating every possible single error permutation of the misspelled string and then checking the dictionary if any make up valid word. Spelling error pattern knowledge is applied to the selected word list and words are sorted in the list based on that knowledge. As a result, we a very powerful suggestion list, in which the correct word is usually placed on the top of the suggestion list.