Low bit-rate speech coder for multimedia communications.

Noman Ahmed Junejo; Naveed Ahmed Junejo; Mukhtar Ali Unar

Author(s)

Noman Ahmed Junejo Institute of Information Technology, Mehran University Engineering and Technology, Jamshoro, Pakistan

Naveed Ahmed Junejo Institute of Information Technology, Mehran University Engineering and Technology, Jamshoro, Pakistan

Mukhtar Ali Unar Institute of Information Technology, Mehran University Engineering and Technology, Jamshoro, Pakistan

Abstract

ITU-T(International Telecommunication Union) recommendation G.723.1 describes a dual rate (5.3 and (6.3)kbps(kilobit/second) Speech-Coding Algorithm. The recommendation specifies a coded representation of voice signal that can be used for compressing the speech or other audio signal component of multimedia services at a very low bit rate as part of the overall H.324 family of standards. ITU-T G 723.1 encodes speech or other audio signals in frames using linear predictive analysis-by-synthesis coding. The coder uses the MP-MLKQ (Multi Pulse Maximum Likelihood Quantization) algorithm for high rate (6.3 kbps) and ACELP (Algebraic Code Excited Linear Prediction) for low rate (5.3 kbps) coding of speech. The paper presents the implementation consideration of G 723.1 standard in JAVA. The high rate has better quality and the lower bit rate give good quality and provides system designers implementers and subscribers with additional flexibility to address issues related with bandwidth consumption, complexity and delay. Our conclusions are based on the observations made by testing our implementation on different platforms. The need for implementing this standard in Java was to build a secure, robust, object oriented and platform independent speech coding software; however the delay (Execution Time) is slightly increased around 10ms.

Publication Details

Page(s) 243-252

DOI DOI not available

Published Journal: Mehran University Research Journal of Engineering and Technology, Volume: 22, Issue: 4, Year: 2003

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