OPTICOM OPERA - V 3.5 User Manual page 101

C H A P T E R 5 : W I D E B A N D A U D I O Q U A L I T Y T E S T I N G
Figure 5.9: Result Style Window
After this last step click on Finish and the selected diagram will appear in the
diagram pane as shown in Figure 5.10. An excerpt of the time signal of one
frame will be shown.
Figure 5.10: Time signals diagram
Spectra
Figure 5.11 shows the signal select wizard step for the spectra diagrams.
Select the spectra of the reference signal, the test signal or the difference
between the reference spectrum and the test spectrum (Noise).
Available result styles for the spectra (see Figure 5.12) are a linear frequency
scale, a Bark scale or a ¼ Bark scale (as outlined in BS.1387). The Y-axis is
always scaled in dB SPL. The Y-axis is depending on the setting of the listening
level as set by the algorithm properties dialog. The spectral resolution is
depending on the sample rate of the input signals. Usually a 2048 point FFT is
used with a Hann window to compute these data (as required by BS.1387).
The resulting diagram will look similar to the one shown in Figure 5.13.
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