Table of Contents
Advertisement
C H A P T E R
2 :
mentioned earlier, the threshold between both worlds - broadcasting and
telecommunication - is floating due to the steadily attempt to further reduce the
bit rates by more efficient coding schemes. Consequently, the overall data rate
scale depicted in the figure should be taken as a course indicator only.
2.4 Which "Measurement" for Which
"Application"?
A summary of the principle assessment scenarios and the corresponding
measurement algorithms applications with OPERA™ follows. This section can
be used as a reference when uncertain which measurement algorithm to apply.
First, remember the recommended perceptual measurement techniques always
try to model the underlying subjective experiment of the corresponding
listening test.
To decide which one is the proper experiment, remember to ask yourself the
following questions:
•
Is this an assessment of
bandwidth > 16kHz)?
•
Would the subject be able to
original
If the answer to both questions is YES, you should apply the PEAQ algorithm.
If the answer to both questions is NO, you should apply PESQ, (or PSQM if
required).
If none of the above seems to apply, an experimental situation outside the
scope of both measurements should probably be considered. In this case,
always consider how subjects would behave in a listening test. In some cases,
however, you may also find that even subjects would not be able to properly
score the sound quality.
In Figure 2.3 the principle setup for a BS.1116 listening test is shown.
Figure 2.4 shows the corresponding situation for a P.800 compliant test
setup.
W H I C H
M E A S U R E M E N T
wide band audio
reference signal
?
18
D O
I
N E E D ?
signals (music, or
compare
the test signal with the
Advertisement
Table of Contents
