11 research outputs found
Predicting the Quality of Synthesized and Natural Speech Impaired by Packet Loss and Coding Using PESQ and P.563 Models
This paper investigates the impact of independent and dependent losses and coding on speech quality predictions
provided by PESQ (also known as ITU-T P.862) and P.563 models, when both naturally-produced and synthesized
speech are used. Two synthesized speech samples generated with two different Text-to-Speech systems
and one naturally-produced sample are investigated. In addition, we assess the variability of PESQ’s and P.563’s
predictions with respect to the type of speech used (naturally-produced or synthesized) and loss conditions as
well as their accuracy, by comparing the predictions with subjective assessments. The results show that there is
no difference between the impact of packet loss on naturally-produced speech and synthesized speech. On the
other hand, the impact of coding is different for the two types of stimuli. In addition, synthesized speech seems
to be insensitive to degradations provided by most of the codecs investigated here. The reasons for those findings
are particularly discussed. Finally, it is concluded that both models are capable of predicting the quality of transmitted
synthesized speech under the investigated conditions to a certain degree. As expected, PESQ achieves the
best performance over almost all of the investigated conditions
Impact of Different Active-Speech-Ratios on PESQ’s Predictions in Simulated VoIP Environment
In this work, we experimentally study how behaviour of the PESQ predictions varies with reference signal characteristic.
In particular we investigate the impact of different Active-Speech-Ratios on speech quality prediction
in simulated VoIP environment from objective and subjective testing point of view. This reference signal characteristic
is defined very broadly by ITU-T Recommendation P.862.3. That is the reason to investigate an impact
of this characteristic on speech quality prediction more in-depth. We assess the variability of PESQ’s predictions
with respect to Active-Speech-Ratio and network conditions, as well as their accuracy, by comparing the
predictions with subjective assessments
Coralline red algae from the Silurian of Gotland indicate that the order Corallinales (Corallinophycidae, Rhodophyta) is much older than previously thought
Devonian operculate corals (Calceolidae, Cnidaria) from the Massif Armoricain, France
The operculate coral Calceola gervillei Bayle, 1878 is described for the first time on the basis of the type material from the Cotentin region of Normandy (North Armorican Domain), from Early Devonian (likely upper Lochkovian to lower Pragian) strata, and is chosen as the type species of the monotypic new genus Gerviphyllum. The new genus is also present in the l\u27Armorique Formation (lower Pragian) of the Plougastel Peninsula (Central Armorican Domain) as Gerviphyllum sp. cf. G. gervillei. One locality in the upper Emsian (Polygnathus serotinus Conodont Zone) Le Fret Formation, on the northern coast of the Crozon Peninsula, has yielded operculate coral specimens described here as ?Chakeola sp., the first (tentative) record of the genus outside eastern Australia, south China and Vietnam. The operculate coral Calceola collini sp. nov. is described from six localities in the early Middle Devonian (Eifelian: Polygnathus costatus Conodont Zone) Saint-Fiacre Formation of the Plougastel and Crozon Peninsulas (Central Armorican Domain), despite the fact that knowledge of the internal characters, especially of the operculum, of the type species Calceola sandalina is very limited. From an extensive review of published references to Calceola from France, we conclude that only the record of Collin (1929) is valid