Cell Phone MP3 Player
and Functional Demo
The image at right is from a demonstration of an
MP3 player application in use on a cell phone. The design was
created to utilize voice recognition as well as traditional navigation
techniques. Illustrated are the principles of accelerator functions
and best practices for using these with speech interfaces. An
obvious example is how speech interfaces are great for traversing
through a heirarchical tree (if the destination is known) while
a visual interface is better for scanning through items in a list.
One caveat is that if the destination is not known, a large heiraarchical
tree becomes very difficult with auditory / speech interfaces.
To this end, we designed this system to use an approach whereupon
all information that is being spoken is represented onscreen and
We designed the volume control to be instantly accessed via voice
and button commands. As well, an incoming phone call would temporarily
lower the volume and alert the user.
Some of the many restrictions imposed on this design by the hardware
include a monochromatic screen of low resolution, a small screen
size, and limited, multi-modal buttons.
We designed with an effort to reduce moding errors - the number
of buttons is limited but the number of functions for each is
high. Each button performs several different functions depending
on which mode you are in.
The picture on the right shows an active scolling animation to
allow for easier browsing of a menu with items 'landmarked' by
their visual position in the list.