Two very different subband coders are described. The first is a modified dynamic bit-allocation-subband coder (D-SBC) designed for variable rate coding situations and easily adaptable to noisy channel environments. It can operate at rates as low as 12 kb/s and still give good quality speech. The second coder is a 16-kb/s waveform coder, based on a combination of subband coding and vector quantization (VQ-SBC). The key feature of this coder is its short coding delay, which makes it suitable for real-time communication networks. The speech quality of both coders has been enhanced by adaptive postfiltering. The coders have been implemented on a single AT&T DSP32 signal processor
Y. Shoham et al., "New Directions in Subband Coding," IEEE Journal on Selected Areas in Communications, Institute of Electrical and Electronics Engineers (IEEE), Institute of Industrial Engineers (IIE), Jan 1988.
The definitive version is available at http://dx.doi.org/10.1109/49.615
Electrical and Computer Engineering
Keywords and Phrases
AT&T; DSP32 Signal Processor; Adaptive Postfiltering; Coding Delay; Digital Filters; Encoding; Filtering and Prediction Theory; Modified Dynamic Bit-Allocation-Subband Coder; Noise; Noisy Channel Environments; Real-Time Communication Networks; Speech Analysis and Processing; Speech Quality; Subband Coding; Vector Quantization; Vocoders; Voice Equipment; Waveform Coder
International Standard Serial Number (ISSN)
Article - Journal
© 1988 Institute of Electrical and Electronics Engineers (IEEE), Institute of Industrial Engineers (IIE), All rights reserved.