Figure 3
From: An improved adaptive gain equalizer for noise reduction with low speech distortion
In plot a , the subband gains g1,k( n ) for the SBA and the proposed solution is shown. In plot b, the noisy speech level estimate A k (n) (solid) and the noise-level estimates B k (n) (dotted), corresponding to the subband gains in plot a, are shown. The signal averages A k (n) and B k (n) are calculated for a signal consisting of only noise in subband k = 1. A sudden increase in the actual noise level takes place after 20 s. In plot c, a time domain plot of the input signal x(n) is shown.