A Multimodal Electronic Travel Aid Device                                  

A. Fusiello, A. Panuccio, V. Murino, F. Fontana, D. Rocchesso                   
Dipartimento di Informatica - Universit`a degli Studi di Verona
Strada Le Grazie, 15 - 37134 Verona, Italy
{fusiello,panuccio,murino,fontana,rocchesso}@sci.univr.it

Abstract
This paper describes an Electronic Travel Aid device,
that may enable blind individuals to see the world with
theirears. Awearable prototype will be assembled using
low-cost hardware: earphones, sunglasses tted with two
micro cameras, anda palmtop computer. The system, which
currently run sona desktopccomputer, is able to detect the
light spot produced by a laser pointer, compute its angular 
position and depth, and generate a corresponding sound
providing the auditory cues for the perception of the position
and distance of the pointed surface patch. It permits
differents on ication modes that can be chosen by drawing,
with the laser pointer, a predened stroke which will be recognized 
by a Hidden Markov Model. In this way the blind
person can use a common pointer as a replacement of the
can e and will interact with the device by using a exible and
natural sketch based interface.                                                                            



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