Adapting Tesseract for Complex Scripts: An Example for Urdu Nastalique

Abstract

Tesseract engine supports multilingual text recognition. However, the recognition of cursive scripts using Tesseract is a challenging task. In this paper, Tesseract engine is analyzed and modified for the recognition of Nastalique writing style for Urdu language which is a very complex and cursive writing style of Arabic script. Original Tesseract system has 65.59% and 65.84% accuracies for 14 and 16 font sizes respectively, whereas the modified system, with reduced search space, gives 97.87% and 97.71% accuracies respectively. The efficiency is also improved from an average of 170 milliseconds (ms) to an average of 84 ms for the recognition of Nastalique document images.