New speech processing issues in IP telephony

Author

Beritelli, F. ; Casale, S. ; Ruggeri, G.

Author_Institution

Dipartimento di Ingegneria Inf. e delle Telecomun., Catania Univ., Italy

Volume

1

fYear

2000

fDate

2000

Firstpage

652

Abstract

In the field of IP telephony, there are various problems to be dealt with before the QoS currently guaranteed by PSTN networks can be achieved. In this paper, we discuss the main causes of degradation in the quality of conversation in an IP communication scenario. We then point out some new QoS problems involved in speech processing. More specifically, two important aspects of discontinuous transmission are dealt with: the impact of the voice activity detector (VAD) on source throughput and the need for an efficient system of comfort noise. In addition, in a differentiated services (DiffServ) scenario we demonstrate the importance of using a multirate intrastandard codec, together with valid criteria for the reconstruction of lost frames

Keywords

Internet telephony; quality of service; speech codecs; speech coding; speech intelligibility; voice communication; DiffServ; IP telephony; PSTN networks; QoS problems; coding process; comfort noise; conversation quality degradation; differentiated services scenario; discontinuous transmission; lost frame reconstruction; multirate intrastandard codec; source throughput; speech processing issues; voice activity detector; Codecs; Delay; Diffserv networks; IP networks; Internet telephony; Protocols; Quality of service; Speech processing; Telecommunication traffic; Throughput;

fLanguage

English

Publisher

ieee

Conference_Titel

Communication Technology Proceedings, 2000. WCC - ICCT 2000. International Conference on

Conference_Location

Beijing

Print_ISBN

0-7803-6394-9

Type

conf

DOI

10.1109/ICCT.2000.889286

Filename

889286