OPTICOM OPERA - V 3.5 User Manual page 136

Raw PSQM
C H A P T E R 6 : T E L E P H O N Y
T E S T I N G
Figure 6.14: Select Signal Window for the excitation diagram type
Figure 6.15 shows the resulting view off the Excitation diagram.
Figure 6.15: The Excitation diagram
Figure 6.16 represents the diagram of the Raw PSQM. There are several
values shown, the description of the result values is given in Table 6.2 below.
The PSQM value indicates the degree of subjective quality degradation as a
result of speech coding. For this reason, when an estimation of subjective
quality on a specific scale is not necessary, e.g. in optimizing parameters of a
codec or in simply comparing the performance of codecs, the PSQM value itself
is quite useful.
B A N D V O I C E Q U A L I T Y
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