title: Urdu Nasta'liq text recognition using implicit segmentation based on multi-dimensional long short term memory neural networks.
abstract: The recognition of Arabic script and its derivatives such as Urdu, Persian, Pashto etc. is a difficult task due to complexity of this script. Particularly, Urdu text recognition is more difficult due to its Nasta'liq writing style. Nasta'liq writing style inherits complex calligraphic nature, which presents major issues to recognition of Urdu text owing to diagonality in writing, high cursiveness, context sensitivity and overlapping of characters. Therefore, the work done for recognition of Arabic script cannot be directly applied to Urdu recognition. We present Multi-dimensional Long Short Term Memory (MDLSTM) Recurrent Neural Networks with an output layer designed for sequence labeling for recognition of printed Urdu text-lines written in the Nasta'liq writing style. Experiments show that MDLSTM attained a recognition accuracy of 98% for the unconstrained Urdu Nasta'liq printed text, which significantly outperforms the state-of-the-art techniques.
authors.affiliation: National University of Sciences and Technology (NUST), Islamabad, Pakistan ; Department of Information Technology, Hazara University, Mansehra, Pakistan.
authors.forename: Saeeda
authors.initials: S
authors.lastname: Naz
authors.affiliation: Department of Information Technology, Hazara University, Mansehra, Pakistan.
authors.forename: Arif Iqbal
authors.initials: AI
authors.lastname: Umar
authors.affiliation: German Research Center for Artificial Intelligence (DFKI), Kaiserslautern, Germany.
authors.forename: Riaz
authors.initials: R
authors.lastname: Ahmed
authors.affiliation: King Saud Bin Abdul Aziz University for Health Sciences, Riyadh, Saudi Arabia.
authors.forename: Muhammad Imran
authors.initials: MI
authors.lastname: Razzak
authors.affiliation: University of Engineering and Technology (UET), Lahore, Pakistan.
authors.forename: Sheikh Faisal
authors.initials: SF
authors.lastname: Rashid
authors.affiliation: National University of Sciences and Technology (NUST), Islamabad, Pakistan.
authors.forename: Faisal
authors.initials: F
authors.lastname: Shafait
keywords: BLSTM; CTC; MDLSTM; Urdu OCR