TIME-VARYING FILTER IN NON-UNIFORM BLOCK CONVOLUTION 

Christian Mller-Tomfelde
IPSI - Integrated Publication and Information Systems Institute
Fraunhofer - IPSI, Dolivostr. 15, D-64293 Darmstadt, Germany
mueller-tomfelde@ipsi.fhg.de  



ABSTRACT
This paper will describe further research on a real-time         
convolution algorithm for long a FIR filter based on non-uniform 
bock partitioning. The static behaviour of the           
algorithm which solves the dilemma between the computational     
load and the latency of the processing operation is well         
examined in literature. New directions are investigated to       
exploit the inherent features of the algorithm and utilise them  
for audio applications. Especially a dynamic exchange of filter  
coefficients or subsets of them of a room impulse response is    
discussed and implemented. Unlike to traditional DSP             
solutions the prototype is realised in portable software objects 
and components that can be compiled on multi-propose             
processing units like off-the-shelf computers with standard 
audio facilities and different operating systems.                


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