In this book, speech transmission quality is modeled on the basis of
perceptual dimensions. The author identifies those dimensions that are
relevant for today's public-switched and packet-based telecommunication
systems, regarding the complete transmission path from the mouth of the
speaker to the ear of the listener. Both narrowband (300-3400 Hz) as
well as wideband (50-7000 Hz) speech transmission is taken into account.
A new analytical assessment method is presented that allows the
dimensions to be rated by non-expert listeners in a direct way. Due to
the efficiency of the test method, a relatively large number of stimuli
can be assessed in auditory tests. The test method is applied in two
auditory experiments. The book gives the evidence that this test method
provides meaningful and reliable results. The resulting dimension scores
together with respective overall quality ratings form the basis for a
new parametric model for the quality estimation of transmitted speech
based on the perceptual dimensions. In a two-step model approach,
instrumental dimension models estimate dimension impairment factors in a
first step. The resulting dimension estimates are combined by a
Euclidean integration function in a second step in order to provide an
estimate of the total impairment.