Fig. 3
From: An adaptive a priori SNR estimator for perceptual speech enhancement
Histograms of a posteriori SNR estimate for different background noises (1st row) for pink noise, (2nd row) for factory noise, and (last row) for babble noise at the 9th critical band mapped with adaptive smoothing factor calculated with different sets of parameters (adaptive smoothing factor calculated at (i) γu=5 dB, (ii) γu=7 dB, (iii) γu=9 dB, and (iv) γu=15 dB). Left figures for noise-only periods and right figures for speech-and-noise periods