Information Technology Reference
In-Depth Information
icons that group together the traits that were the most common to the experiences of
the people questioned.
More recently, Conversy [CON 00] introduced the notion of premastered sound
icons. These consist of sound icons with certain acoustic properties that can vary
according to the information that is to be conveyed. The author proposes, for
example, the sonification of computing processes that occur as background tasks
[CON 98]. For this he uses a simulation of sounds emitted by the wind: white noise
filtered by a narrow
-
band noise
9
, whose central frequency varies according to the
state of the process.
8.3.3.
Mixed approaches
8.3.3.1.
Earcons and vocal synthesis
Vargas and Anderson [VAR 03] propose combining earcons and vocal synthesis
in order to sonify a user interface in an automobile. The interface enables control of
the different accessories of the car (e.g. radio, lights, etc.). The authors chose to use
earcons to represent the hierarchy of the menu and vocal synthesis to represent the
semantic content of items. The main menu includes four main menus (lights,
windscreen wiper, ventilation and radio), the name of the item is announced each
time it is visited, and the earcon is diffused before the vocal synthesis.
The description of the associated earcons is as follows:
- each family of the basic level is accompanied by the tone of an instrument:
lights = piano, windscreen wiper = singing, ventilation = bells, radio = brass.
Alternate use of arpeggios and chords;
- each sub level inherits from the instrument and notes of the level above. The
differentiation of each item is carried out according to the rhythm and melody;
- the hierarchical level is given by a brief percussive sound diffused before the
earcon.
Compared to the use of simple vocal synthesis (without earcons), the evaluation
of this system shows that even if the navigation is slower, users have a more
efficient navigation in terms of the number of times they press on the keys.
8.3.3.2.
Manipulation of vocal synthesis parameters
Shajahan and Irani [SHA 07] propose an original method of navigation aid in a
hierarchical menu, thanks to vocal synthesis including the parameter synthesis (e.g.
9 White noise processed through a band-pass filter.
