Linear inter-frame dependencies for very low bit-rate speech coding

• Published in: Speech communication Vol. 34; no. 4; pp. 333 - 349
• Main Authors: Lopez-Soler, Juan M, Sanchez, Victoria, De la Torre, Angel, Rubio-Ayuso, Antonio J
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-07-2001; Elsevier
• Subjects: Applied sciences; Exact sciences and technology; Information, signal and communications theory; Inter-frame dependencies; Interpolation; Quantization; Signal processing; Speech coding; Speech processing; Telecommunications and information theory; Quantization; Interpolation; Speech coding; Inter-frame dependencies; Performance evaluation; Signal compression; Coding; Digital processing; Algorithm; Speech processing
• ISSN: 0167-6393; 1872-7182
• DOI: 10.1016/S0167-6393(00)00039-X

We have studied experimentally the operational rate-distortion performance for very low bit-rate speech coding using linear inter-frame dependencies. We propose an algorithm that efficiently combines quantization and linear interpolation procedures. With a maximum delay of 200 ms, for the spectral envelope information and using line spectrum pair (LSP) parameters as input space the proposed algorithm performs best at rates of between 200 and 300 b/s. For comparison's sake several other procedures such as the
multi-frame encoder (Kemp D., Collura J., Tremain T., Multi-Frame Coding of LPC Parameters at 600–800 bps. In: IEEE ICASSP-91, 1991, pp. 609–612) and
matrix quantizer (Tsao C., Gray R., Matrix quantizer design for LPC speech using the generalized Lloyd algorithm. IEEE Transactions on Acoustics, Speech, and Signal Processing ASSP-33, 1985, 537–545) are simulated. Furthermore, a mono-dimensional version of the proposed procedure is shown experimentally to provide the best operational rate-distortion trade-off when coding a parametric representation (pitch, gain and voicing information) of the excitation signal.