Automatic recognition of the American sign language fingerspelling alphabet to assist people living with speech or hearing impairments

  • Luis Quesada
  • Gustavo López
  • Luis Guerrero
Original Research


Sign languages are natural languages used mostly by deaf and hard of hearing people. Different development opportunities for people with these disabilities are limited because of communication problems. The advances in technology to recognize signs and gestures will make computer supported interpretation of sign languages possible. There are more than 137 different sign languages around the world; therefore, a system that interprets them could be beneficial to all, especially to the Deaf Community. This paper presents a system based on hand tracking devices (Leap Motion and Intel RealSense), used for signs recognition. The system uses a Support Vector Machine for sign classification. Different evaluations of the system were performed with over 50 individuals; and remarkable recognition accuracy was achieved with selected signs (100% accuracy was achieved recognizing some signs). Furthermore, an exploration on the Leap Motion and the Intel RealSense potential as a hand tracking devices for sign language recognition using the American Sign Language fingerspelling alphabet was performed.


American sign language Leap motion Intel RealSense Support vector machine Automatic sign language recognition Natural user interfaces 



This work was partially supported by the Escuela de Ciencias de la Computación e Informática at Universidad de Costa Rica (ECCI-UCR) grant No. 320-B5-291, by Centro de Investigaciones en Tecnologías de la Información y Comunicación de la Universidad de Costa Rica (CITIC-UCR), and by Ministerio de Ciencia, Tecnología y Telecomunicaciones (MICITT) and Consejo Nacional para Investigaciones Científicas y Tecnológicas (CONICIT) of the Government of Costa Rica.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.Computer Science and Informatics Department (ECCI)University of Costa RicaMontes de OcaCosta Rica
  2. 2.Research Center for Communication and Information Technologies (CITIC)University of Costa RicaMontes de OcaCosta Rica

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