Study on the design of digital reverberation processor
LU Guang-hua · Journal of Circuits and Systems · 2007
The impulse response of a digital reverberation processor often has a very long length,which makes the real-time processing very difficult with small error,store and delay. This paper proposes to process the high-frequency part and low-frequency part separately. That is,the low-frequency parts of input signal and impulse response are separately decimated with lower sampling rate,the decimated impulse response forms a FIR filter,the decimated low-frequency part of the input signal passes this FIR filter and is then interpolated with zeroes,and then passes a low-pass filter to obtain the output. The energy of the high-frequency part of an impulse response,when time is long,tends to zero. So the high-frequency output can be obtained by cutting it and then using a transform method. For TMS320C5402 DSP,this method can achieve real-time processing with small error,store and delay.