Digital Signal Processing Reference
In-Depth Information
Figure 10-9.
LAR-distances distances between the clean input and various output signals:
unprocessed output (Noisy), outputs of the SAF, STDWF and SAFWF techniques in four new
recording environments.
To further verify the system performance, we repeated the objective LAR
tests using four other noise sets at 0 dB SNR. Two were recorded while
walking (Walk-Mall), and sitting (Sit-Mall2) in a shopping mall. Two
different office noise sets (Office1 and Office2) were also recorded. The
recording methods were exactly the same as those used in Section 3. The
objective evaluation results (keeping the same system parameters as in
previous evaluations of Figure 10-7) are depicted in Figure 10-9 where the
noises (from left to right) are sorted according to the increasing severity of
the lowpass nature. As evident from Figure 10-9, the results are consistent
with those presented in Figure 10-7.
Also, we have done some informal listening tests confirming the
objective assessments. The artifacts produced by the STDWF technique are
considerably reduced by applying the Wiener filter after the adaptive
filtering.
