Multiple impulse excitation speech encoder and decoder

Details Multiple impulse excitation speech encoder and decoder Multiple impulse excitation speech encoder and decoder

2001-03-14

2002-05-07

Banks-Harold, Marsha D. (Department: 2654)

Data processing: speech signal processing, linguistics, language

Speech signal processing

For storage or transmission

C704S201000, C704S219000

Reexamination Certificate

active

06385577

ABSTRACT:

BACKGROUND
This invention relates to digital voice coders performing at relatively low voice rates but maintaining high voice quality. In particular, it relates to improved multipulse linear predictive voice coders.
The multipulse coder incorporates the linear predictive all-pole filter (LPC filter). The basic function of a multipulse coder is finding a suitable excitation pattern for the LPC all-pole filter which produces an output that closely matches the original speech waveform. The excitation signal is a series of weighted impulses. The weight values and impulse locations are found in a systematic manner. The selection of a weight and location of an excitation impulse is obtained by minimizing an error criterion between the all-pole filter output and the original speech signal. Some multipulse coders incorporate a perceptual weighting filter in the error criterion function. This filter serves to frequency weight the error which in essence allows more error in the format regions of the speech signal and less in low energy portions of the spectrum. Incorporation of pitch filters improve the performance, of multipulse speech coders. This is done by modeling the long term redundancy of the speech signal thereby allowing the excitation signal to account for the pitch related properties of the signal.
SUMMARY
A version of a speech signal and an output of a pitch synthesis filter and a linear predictive all-pole (LPC) filter is received. A system impulse response is produced based on in part the received pitch synthesis filter and LPC output. An excitation pulse location is determined so that the determined location minimizes an error between the speech signal version and the system impulse response. The speech signal is encoded with a representation of the determined location.


REFERENCES:
patent: 4618982 (1986-10-01), Horvath et al.
patent: 4669120 (1987-05-01), Ono
patent: 4776015 (1988-10-01), Takeda et al.
patent: 4815134 (1989-03-01), Picone et al.
patent: 4845753 (1989-07-01), Yasunaga
patent: 4868867 (1989-09-01), Davidson et al.
patent: 4890327 (1989-12-01), Bertrand et al.
patent: 4980916 (1990-12-01), Zinser
patent: 4991213 (1991-02-01), Wilson
patent: 5001759 (1991-03-01), Fukui
patent: 5027405 (1991-06-01), Ozawa
patent: 5235670 (1993-08-01), Lin et al.
patent: 5265167 (1993-11-01), Akamine et al.
patent: 5307441 (1994-04-01), Tzeng
patent: 5999899 (1999-12-01), Robinson
patent: 6006174 (1999-12-01), Lin et al.
patent: 6223152 (2001-04-01), Lin et al.
patent: WO8602726 (1986-06-01), None
Proc. ICASSP '82, A New Model of LPC Excitation for Producing Natural-Sounding Speech at Low Bit Rates, B.S. Atal and J.R. Remde, pp 614-617, Apr., 1982.
Proc. ICASSP '84, Improving Performance of Multi-Pulse Coders at Low Bit Rates, S. Singhal and B.S. Atal, paper 1.3, Mar. 1984.
Proc. ICASSP '84, Efficient Computation and Encoding of the Multiple Excitation for LPC, M. Berouti et al., paper 10.1, Mar., 1984.
Proc. ICASSP '86, Implementation of Multi-Pulse Coder on a Single Chip Floating-Point Signal Processor, H. Alrutz, paper 44.3, Apr., 1986.
Digital Telephony, John Bellamy, pp 153-154, 1991.
Veeneman et al., “Computationally Efficient Stochastic Coding of Speech,” 1990 IEEE 40th Vehicular Technology Conference, May 1990, pp. 331-335.

Affiliated with

Also associated with

Rating

Multiple impulse excitation speech encoder and decoder does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Multiple impulse excitation speech encoder and decoder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multiple impulse excitation speech encoder and decoder will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2903642