Title
Investigation of speech recognition over IP channels.
Abstract
In this paper we investigate the effects of IP channels on speech recognition systems and methods to recover the associated performance degradation. There are three major VoIP (voice over IP) distortion sources: speech encoding-decoding (codecs), packet loss and jitter (time-delay). To speech recognition systems distortions are mainly from packet loss and the speech codecs. Their effects on the recognizer's performance are systematically investigated by using four different ITU-T recommended speech codecs. The results show that the speech codecs introduce bigger degradation than the packet losses (random and burst). To recover the codec degradations we have applied the MLLR adaptation and a data-mixed retraining method. These techniques reduce the degradation by about 50%.
Year
DOI
Venue
2002
10.1109/ICASSP.2002.5745487
ICASSP
Keywords
Field
DocType
packet loss,speech recognition,voice over ip,wireless communication,hidden markov models,encoding
Voice activity detection,Computer science,Network packet,Packet loss,PSQM,Speech recognition,Codec2,Jitter,Acoustic model,Voice over IP
Conference
Volume
ISSN
ISBN
4
1520-6149
0-7803-7402-9
Citations 
PageRank 
References 
5
0.59
7
Authors
4
Name
Order
Citations
PageRank
Jim Van Sciver1131.61
Jeff Z. Ma213315.79
Filiep Vanpoucke3152.38
Hugo Van hamme456577.43