The visual interface enables users to
understand musical parameters, such as chords
and velocity. The visual interface represents the
sounds as components of the instrument that
make sounds themselves.
2. How to embody a sense of playing with 3D
objects that reflect musical parameters.
Musical factors that can be operated by users
must conform to users' abilities to perform and
knowledge of music.
Based on the above two points, we constructed a
visual interface that can dynamically display states of
performance in the new environment of musical
performance.
3 System Architecture
3.1 Session System Considering Musical
Construction
prepared phrases
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send looing phrases
send looping phrases
send MIDI messages
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musical part
Figure 2: Architecture of the musical part
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Figure 1: Architecture of prototype system
Figure 1 shows the architecture of the prototype
session system. The visual part is composed of a
graphic workstation (Windows2000). The musical
part is composed of a Macintosh G4, a sound source
(XV5080, Roland), and three input device interfaces.
The graphic workstation and Macintosh G4
communicate through MIDI. The Macintosh G4
receives data from the interface, processes and sends
the performance data to the graphic workstation and
the sound source.
Based on data from Macintosh G4, the graphic
workstation displays the visual interface while the
sound source plays music of the session.
Figure 2 shows the architecture of the musical
part. The computer manipulates previously prepared
looping phrases and plays music by sending the
phrases to the sound source. Users can play music by
selecting looping phrases. The selected looping
phrases are sent as MIDI messages to the computer.
There are different kinds of the looping phrase.
Each phrase has three atmospheres such as lively, a
little lively, and calm. Users can also modify these
phrase parameters.
3.2 Structure of Graphical Interface
Figure 3 shows an example of a scene provided
by the visual interface. The visual interface displays
some objects and the scene. An object is a deformed
cactus based on the image of the music preformed by
the session system. Each cactus is animated with an
instrument. The cactuses' dance is changed by the
phrases the users have performed. Users can confirm
their own currently playing phrase by way of the CG.
Further more, users can pleasantly understand the
difference between their own performance and
another user's performance at a glance.
The visual part receives the MIDI message as a
parameter from the musical part. The parameter from
the musical part corresponds to the atmosphere of the
performance as each user plays, the distinction of the
phrases, and so on. The visual interface displays the
state of each instrument's performance based on these
parameters. The sum of the whole musical
atmosphere is represented as the whole picture.
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