Hybrid coding of mixed signals for digital covert audio surveillance

Author

Mason, Michael ; Sridharan, Sridha ; Chandran, Vinod

Author_Institution

Sch. of Electr. & Electron. Syst. Eng., Queensland Univ. of Technol., Brisbane, Qld., Australia

Volume

6

fYear

2000

fDate

2000

Firstpage

3654

Abstract

An overview of the requirements of digital covert audio acquisition (DCAA) is provided and a scalable hybrid coder tuned for the coding of intelligible speech in a covert environment is proposed. The codec incorporates linear predictive coding (LPC) and an M-band discrete wavelet transform (DWT) to offer effective intelligible speech coding in the presence of multiple signal sources at bit rates between 8 kbps and 32 kbps. The results of informal intelligibility testing and an analysis of the algorithm´s complexity are presented to demonstrate the performance of the proposed coder

Keywords

computational complexity; discrete wavelet transforms; linear predictive coding; speech codecs; speech coding; speech intelligibility; surveillance; transform coding; 32 kbit/s; 8 kbit/s; DWT; LPC; M-band discrete wavelet transform; algorithm complexity; bit rates; codec; coder performance; covert environment; digital covert audio acquisition; digital covert audio surveillance; hybrid coding; informal intelligibility testing; intelligible speech coding; law enforcement; linear predictive coding; mixed signals; multiple signal sources; scalable hybrid coder; scalable hybrid parametric-transform coder; Australia; Bandwidth; Data compression; Discrete wavelet transforms; Linear predictive coding; Monitoring; Radio access networks; Speech coding; Surveillance; Systems engineering and theory;

fLanguage

English

Publisher

ieee

Conference_Titel

Acoustics, Speech, and Signal Processing, 2000. ICASSP '00. Proceedings. 2000 IEEE International Conference on

Conference_Location

Istanbul

ISSN

1520-6149

Print_ISBN

0-7803-6293-4

Type

conf

DOI

10.1109/ICASSP.2000.860194

Filename

860194