Speech Coding with Dynamic Bit Allocation (Multimode Coding)

Recent research on narrow to medium band speech coding has concentrated on the efficient transmission of the excitation parameters. Using model based excitation analysis techniques, coders with Analysis-by-Synthesis configuration, such as Multi-Pulse Excited LPC (MPLPC) [1] or Code Excited LPC (CELP) [2], can successfully reduce the transmission bit rate for excitation parameters and can provide good speech quality at bit rates around 8 kb/s.

[1]  Manfred R. Schroeder,et al.  Code-excited linear prediction(CELP): High-quality speech at very low bit rates , 1985, ICASSP '85. IEEE International Conference on Acoustics, Speech, and Signal Processing.

[2]  Allen Gersho,et al.  Vector excitation coding with dynamic bit allocation , 1988, IEEE Global Telecommunications Conference and Exhibition. Communications for the Information Age.

[3]  Nuggehally Sampath Jayant,et al.  Speech coding with time-varying bit allocations to excitation and LPC parameters , 1989, International Conference on Acoustics, Speech, and Signal Processing,.

[4]  Shoji Tominaga,et al.  A high-efficiency speech coding algorithm based on ADPCM with multi-quantizer , 1986, ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing.

[5]  Shoji Tominaga,et al.  ADPCM with a multiquantizer for speech coding , 1988, IEEE J. Sel. Areas Commun..

[6]  Bishnu S. Atal,et al.  A new model of LPC excitation for producing natural-sounding speech at low bit rates , 1982, ICASSP.

[7]  Robert M. Gray,et al.  Multimode coding: application to CELP , 1989, International Conference on Acoustics, Speech, and Signal Processing,.

[8]  John Makhoul,et al.  Variable Frame Rate Transmission: A Review of Methodology and Application to Narrow-Band LPC Speech Coding , 1982, IEEE Trans. Commun..

[9]  Robert M. Gray,et al.  Multimode coding: A novel approach to narrow‐ and medium‐band coding , 1988 .

[10]  B. Atal.  Stochastic Gaussian model for low-bit rate coding of LPC area parameters , 1987, ICASSP '87. IEEE International Conference on Acoustics, Speech, and Signal Processing.