Conducting is the act of directing a musical perfor¬mance by way of visible gestures. In a real orchestra, different performers will play their instruments louder, softer, with different artistic expressions, etc. Instrument empha¬sis is the ability to change the aspects of the individual per¬formance of an instrument or section of instruments. With instrument emphasis, a conductor can per¬sonalize a musical piece, so performances sound unique, all due to the majesty of the conductor’s imagination and expres¬siveness. Without such emphasis, performances would be boring and repetitive.
Instrument emphasis has no predefined gestures and can be accomplished in almost any manner. It often involves the gestures used to define tempo or expression, directed towards the desired instrument section. For the human musician, recognizing the emphasis from the conductor becomes trivial with practice. For the computer, the conductor’s gestures are not obvious and computers tend to interpret the hand’s motion simply as its position. To recognize instrument emphasis, the computer needs a means to under¬stand the hand’s motion more like a human would.
In this paper, we present an approach to help the computer understand the hand’s motion through two different but related analyses. We hope to show that by combining the features obtained from the two analyses of the conductor’s hand motion, we can ascertain instrument em¬phasis.
A major achievement of this work is the ability to detect instrument emphasis in real-time. The results of this effort will be combined with other components under construction to build a complete system.

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