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The modelling of the network effects on the quality of speech in the Voice over IP networks is the main focus of this paper. The main purpose of the ideas presented here is to achieve high-precision estimation of the speech quality in the environments where the classical approaches of speech quality determination fail. To achieve this high precision a modular neural network model is used to map the...
The paper deals with the modelling of the network effects on the quality of speech in the Voice over IP networks. The main purpose of the ideas presented here is to achieve highprecision estimation of the speech quality in the environment in which the classical approaches of speech quality determination fail. To achieve such a high precision a modular neural network model is used to map the effects...
This paper undertakes a detailed comparative analysis of both PESQ and VISQOL model behaviour, when tested against speech samples modified through playout delay adjustments. The adjustments are typical (in extent and magnitude) to those introduced by VoIP jitter buffer algorithms. Furthermore, the analysis examines the impact of adjustment location as well as speaker factors on MOS scores predicted...
This paper deals with analysis of relation between packet delay variations (jitter), length of jitter buffer and final voice transmission quality. For adjusting of IP channel network emulator NISTNet is used. For adjusting of buffer length VoIP client Linphone is used. Criterion of transmission quality is a MOS parameter investigated with an algorithms ITU-T P.862 PESQ and P.863 POLQA.
This paper deals with analysis of relation between IP channel characteristics and final voice transmission quality. For adjusting of IP channel network emulator NISTNet is used. Criterion of transmission quality is a MOS parameter investigated with an algorithms ITU-T P.862 PESQ, future P.863 POLQA and P.563 3SQM. The following characteristics have been explored: codec PCM, codec Speex, jitter and...
The evolution of telecommunications technology from circuit to packet switching, in which the Internet is the great paradigm, offers nowadays more flexibility in services and higher efficiency in the transport infrastructure that was not experienced before. As consequence, several new services have emerged. Among them, Voice over IP (VoIP) is, indubitably, one of the most popular, mainly because it...
Voice over Internet Protocol (VoIP) is a technology that transports voice data packets across packet switched networks using the Internet Protocol (IP). Perceived speech quality is the key metric for QoS for VoIP applications. The most popular objective measurement method for VoIP voice is E-Model. The primary aim of this work is to investigate the how the delay affect the VoIP quality and how to...
Voice over Internet protocol (VoIP) is a technology that transports voice data packets across packet switched networks using the Internet protocol (IP). However, the current Internet, which was originally designed for data communications, provides best-effort service only, and does not guarantee to transmission quality. As known, packet delay dramatically degrades the quality of VoIP calls. It is...
PESQ is the international standard for objective speech quality measurement and has been widely used in industry for voice quality assessment for VoIP products and systems. However, current research efforts involving PESQ are mainly focused on simulated IP networks. The need remains to establish how accurate PESQ is when used in real wireless systems, especially in new wireless VoIP environment. The...
The main requirement in the Voice over IP technology is a good quality of received voice signal during communication between subscribers. The signal quality can be influenced by many factors such as packet loss, jitter, packet delay, noise etc. and it can be measured by number of methods. The main purpose of this paper is the investigation of an impact of different noise types and different noise...
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