Geometric Shape Recognition for Visually Challenged People.

Date of Submission

December 2013

Date of Award

Winter 12-12-2014

Institute Name (Publisher)

Indian Statistical Institute

Document Type

Master's Dissertation

Degree Name

Master of Technology

Subject Name

Computer Science


Advance Computing and Microelectronics Unit (ACMU-Kolkata)


Bhattacharya, Bhargab Bikram (ACMU-Kolkata; ISI)

Abstract (Summary of the Work)

Our perceptual system has the ability to reconstruct the shape of objects from sparse partial data. The way how the brain does this led the pattern recognition researchers to data condensation problem. However such a task is very difficult to accomplice by a visually challenged person. They don’t have the ability to match pairs of points on the same vertical or horizontal line. They use a is a tactile writing system called Braille system created by Frenchman Louis Braille. This system is used for books, menus, signs, elevator buttons, and currency. Braille-users can read computer screens and other electronic supports thanks to refreshable braille displays. They can write braille with the original slate and stylus or type it on a braille writer, such as a portable braille note-taker, or on a computer that prints with a braille embosser. This is the way to encode alphabetic symbols. However expressing non-textual information such as maps, paintings, graphs and diagrams to a blind person is a challenging problem. This is done by Tactile Maps. These are images that use elevated surfaces so that a visually impaired person can feel them. But this technique is costly. An easier way of doing this is to put some elevated dots along the edges of the diagrams so that they can touch and connect the elevated dots to reconstruct the underlying geometric shape. If the elevated dots are placed close enough along an edge, reconstruction by perception can be made unambiguous. Our problem determines the necessary number of elevated dots and their positions. This leads to a solution for manufacturing cheap Tactile/Braille maps, which can be used for depicting necessary floor-plans in public places or for teaching in classrooms for visually challenged people. We will refer to this problem as an unlabeled version of connect-the-dots.


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Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.


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