A Systematic Review on the Chronological Development of Bangla Sign Language Recognition Systems

Despite sign language being the primary medium of conversation with deaf and dumb (DD) individuals, it is hard to grasp for any class of people, making communication immensely challenging. Bengali being one of the most spoken languages globally, significant research works on Bangla Sign Language (BdSL) have come to light to deal with this challenge. In recent years, researchers from diverse backgrounds have proposed solutions to automate the process of BdSL recognition. In this literature review, we have explored the trends of research on BdSL by comparing incorporated features and evaluation results of systems between 2002-2021 and techniques applied on different existing and new datasets. We have also collected and combined metadata from datasets of all BdSL Alphabets and numerics used so far. The literature findings of this paper indicate that most proposed models perform well on images containing static and single-handed signs but, performance falls significantly in complex backgrounds. Moreover, we focused on identifying insights and similarities of the existing system, finding research gaps and propose possible future directions. We expect this article will draw the attention of more researchers into this domain and this is the first identifiable academic literature review of BdSL recognition systems to the best of our knowledge.