Information Technology Reference
In-Depth Information
Data input
Camera
Accelerometer
Event
analysis
Spatial position
analysis
Gesture recognition
OSC messages
Mapping of gestures
into application events
OSC messages
Polyphony control
Open GL
drawing
Sound generation
Projector
Sound Table
Audio output
Visual output
Figure 8.4
System processing flow.
Sting and release is achieved by bringing the stick device with keeping its
head on the table. It corresponds to a mouse drag operation. Messages with
2-D coordinate values of the focus point are generated at certain intervals
during the drag gesture.
Attack is a gesture of swinging the device downward quickly as is seen in
the drum play. 2-D coordinate values of the attack point, height of the device
at the lowered position, and velocity of the attack motion are considered as
message parameters.
Flick is a gesture of handling a virtual object on the table with a light quick
blow. This gesture is expressed internally by a message with parameters of
device position and motion velocity.
Tilt is a gesture of tilting the stick device. This gesture should be carried
out while pushing a button on the device. Posture data of the stick device in
3-D and its height from the tabletop are sent with a message. Here, though
it is possible to have acceleration along three axes by the use of an acceler-
ometer provided in Wii Remote in reality, we don't take the yaw angle into
account since it is not considered essential this time. Furthermore, this can
help reduce a gesture recognition error.
