Abstract
In this paper, we propose an embedded variable bit-rate (VBR) audio coder to provide the fittest quality of service (QoS) and better connectivity of service for the ubiquitous speech communications. It has scalable bandwidth for narrowband to wideband speech signal, and embedded 8 32 kbit/s VBR corresponding to the network condition and terminal capacity. For the design of the embedded VBR coder, the narrowband signals are compressed by an existing standard speech coding method for the compatibility with G.729 coder, and then the other signals are compressed hierarchically on the basis of CELP enhancement and transform coding with temporal noise shaping (TNS) method. By the objective and subjective quality tests, it is shown that the proposed embedded VBR audio coder provides a reasonable quality compared with existing audio coders such as G.722 and G.722.2 in terms of mean opinion score (MOS) and perceptual evaluation of speech quality of wideband (PESQ-WB).
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Kim, D.Y., Park, J.W. (2007). An Embedded Variable Bit-Rate Audio Coder for Ubiquitous Speech Communications. In: Stajano, F., Kim, H.J., Chae, JS., Kim, SD. (eds) Ubiquitous Convergence Technology. ICUCT 2006. Lecture Notes in Computer Science, vol 4412. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-71789-8_4
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DOI: https://doi.org/10.1007/978-3-540-71789-8_4
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-71788-1
Online ISBN: 978-3-540-71789-8
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