1. Signal Processing and Recognition Group, Universidad Nacional de Colombia, Km. 7, Manizales, Colombia
2. University of Applied Sciences, Upper Austria, 4600 Wels, Austria
3. Universidad de Manizales, Carrera 9, No. 19-03, Manizales, Colombia
4. Technological Institute of Informatics (ITI), Polytechnic University of Valencia, Alcoi Campus, Plaza Ferrandiz y Carbonell 2, 03801 Alcoy, Spain