Urdu ligature recognition techniques-A review

Optical Character Recognition plays indispensable role to recognize images from natural text images. As we know numerous languages are used all over the world but Urdu OCR is an emerging research area. Researchers on Urdu ligature recognition have received a great attention and continuously lot of research work is ongoing. Ligatures based Urdu language OCR is more preferable than characters. Hence, researchers are focusing more on ligature recognition in current time. Some reviews of different ligature recognition techniques for cursive Urdu OCR script are also provided in this paper. The cursive script structure has a variety of shapes and multiple writing styles produce many problems. Ligature recognition on script languages such as Latin, Chinese and Japanese is tough but it is more complex for Urdu script. Consequently, required advanced techniques for Urdu ligature recognition. The aim of this review is to explore several new opportunities and challenges for future research and compared the existing different techniques till date.