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Towards The Development of Virtual Keyboard: An Activity Recognition Approach

This paper presents an activity recognition based scheme for the development of the virtual keyboard for mobile and portable computing devices. Keystrokes activities are modeled in terms of the joints movements of fingers using kinematic model of hand. Generic activity recognition system is employed for keystroke detection and recognition. Hands activities on a flat surface are captured using mobile's secondary camera. Scheme composed of two steps: first, low-level features are extracted in terms of joints trajectories estimation using finger joints localization and optical flow calculation. Second, trajectories are further interpreted into feature vectors. Feature vectors are trained and classified using Hidden Markov Models leading towards the keystrokes recognition. Real- time implementation covers the accurate detection and recognition of 78 keys of the keyboard, thus providing enriched set of keys to the users of mobile devices. (Yousaf MH, Habib HA, Azhar K, Hussain F, Rizwan M, Asim MM. Towards the Development of Virtual Keyboard: An Activity Recognition Approach. Life Sci J 2013;10(10s):275-282) (ISSN:1097-8135). http://www.lifesciencesite.com. 45