Digital speech coder having improved vector excitation source

Details Digital speech coder having improved vector excitation source Digital speech coder having improved vector excitation source

1988-01-07

1989-03-28

Kemeny, Emanuel S.

Electrical audio signal processing systems and devices

One-way audio signal program distribution

Public address system

G10L 500

Patent

active

048171573

ABSTRACT:
An improved excitation vector generation and search technique (FIG. 1) is described for a code-excited linear prediction (CELP) speech coder (100) using a codebook of excitation code vectors. A set of M basis vectors V.sub.m (n) are used along with the excitation signal codewords (i) to generate the codebook of excitation vectors u.sub.i (n) according to a "vector sum" technique (120) of converting the selector codewords into a plurality of interim data signals, multiplying the set of M basis vectors by the interim data signals, and summing the resultant vectors to produce the set of 2.sup.M codebook vectors. The entire codebook of 2.sup.M possible excitation vectors is efficiently searched by using the vector sum generation technique with the M basis vectors--without ever having to generate and evaluate each of the 2.sup.M code vectors themselves. Furthermore, only M basis vectors need to be stored in memory (114), as opposed to all 2.sup.M code vectors.

REFERENCES:
patent: 3631520 (1971-12-01), Atal
patent: 4133976 (1979-01-01), Atal et al.
patent: 4220819 (1980-09-01), Atal
patent: 4472832 (1984-08-01), Atal et al.
Atal, B. S., "Predictive Coding of Speech at Low Bit Rates", IEEE Transactions on Communications, vol. COM-30, No. 4, (Apr. 1982), pp. 600-614.
Atal, B. S., "Stochastic Coding of Speech Signals at Very Low Bit Rates", Proc. Int. Conf. Commun., vol. 3, paper No. 48.1 (May 14-17, 1984).
Davidson, G., and Gersho, A., "Complexity Reduction Methods for Vector Excitation Coding", IEEE-IECEI-ASJ International Conference on Acoustics, Speech, and Signal Processing, vol. 4, (Apr. 7-11, 1986), pp. 3055.3058.
Kabal, P., "Code Excited Linear Prediction Coding of Speech at 4.8 kb/s", INRS-Telecommunications Technical Report, No. 87-36, (Jul. 1987), pp. 1-16.
Kroon, P., Deprettere, E. F., and Sluyter, R. J., "Regular-Pulse Excitation-A Novel Approach to Effective and Efficient Multipulse Coding of Speech", IEEE Transactions on Acoustics, Speech, and Signal Processing, vol. ASSP-34, No. 5, (Oct. 1986), pp. 1054-1063.
Lin, Daniel, "Speech Coding Using Efficient Pseudo-Stochastic Block Codes", IEEE International Conference on Acoustics, Speech and Signal Processing, vol. 3, (Apr. 6-9, 1987), pp. 1354-1357.
Moncet, J. L., and Kabal, P., "Codeword Selection for CELP Coders", INRS-Telecommunications Technical Report, No. 87-35, (July. 1987), pp. 1-22.
Schroeder, M. R., and Atal, B. S., "Code-Excited Linear Prediction (CELP): High-Quality Speech at Very Low Bit Rates" Proc. IEEE International Conference on Acoustics, Speech and Signal Processing, vol. 3, (Mar 26-29, 1985), pp. 937-940.
Schroeder, M. R., "Linear Predictive Coding of Speech: Review and Current Directions", IEEE Communications Magazine, vol. 23, No. 8, (Aug. 1985), pp. 54-61.
Schroeder, M. R., and Sloane, N. J. A., "New Permutation Codes Using Hadamard Unscrambling", IEEE Transactions on Information Theory, vol. IT-33, No. 1, (Jan. 1987), pp. 144-146.
Trancoso, I. M., and Atal, B. S., "Efficient Procedures for Finding the Optimum Innovation in Stochastic Coders", IEEE International Conference on Acoustics, Speech, and Signal Processing, vol. 4, (Apr. 7-11, 1986), pp. 2375-2378.
Gerson, co-pending U.S. patent application Ser. No. 07/212,455, filed Jun. 30, 1988.

Affiliated with

Also associated with

Rating

Digital speech coder having improved vector excitation source does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Digital speech coder having improved vector excitation source, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Digital speech coder having improved vector excitation source will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1666172