An Interactive Beat Tracking and Visualisation System    

Simon Dixon    
Austrian Research Institute for Artificial Intelligence, Vienna
email: simon@oef ai.at

Abstract
This paper describes Beat Root, a system which performs 
automatic beat tracking on audio or MIDI data and creates a            
graphical and audio representation of the data and results,         
as part of an interactive interface for correcting errors or    
selecting alternative metrical levels for beat tracking. The     
graphical interface displays the input data and the computed       
beat times, and allows the user to add, delete and adjust the         
beat times and then automatically re-track the remaining data      
based on the user input. The system also provides audio feedback
consisting of the original input data accompanied by a         
percussion instrument sounding at the computed beat times.        
At the heart of the system is abe attracking algorithm which         
estimate stempo based on the frequency of occurrence of the         
various time durations between pairs of note on set times, and       
then uses a multiple hypothesis search to nd the sequence         
of note on sets that best matches one of the possible tempos.         
The primary application of this system is in the analysis of        
tempo and timing in musical performance, although the beat         
tracking algorithm itself has been shown to perform at least        
as well as other state-of-the-art systems.                      



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