Patent
1993-04-28
1997-11-11
Knepper, David D.
395 218, 395 22, G10L 706
Patent
active
056872810
ABSTRACT:
A sampled analog signal is filtered by a short-term prediction filter. The result, a segmented residual signal, is transformed from a time domain to a frequency domain into several frequency components, each having a frequency-component amplitude. If a number of new amplitudes is calculated by combining the several frequency-component amplitudes, such that the number of new amplitudes is smaller than the several frequency-component amplitudes, a more efficient coder is created. The reduction of the quality of speech coding, due to loss of information, could be decreased if this calculation is based on the so-called Bark scale (critical frequency bands). In a corresponding speech decoder, at the hand of the number of new amplitudes several new frequency-component amplitude are calculated (the number of new amplitudes being smaller than the several new frequency-component amplitudes), which then are inverse transformed from a frequency domain to a time domain into new subsegments. These new subsegments are inverse filtered by an inverse short-term prediction filter to generate a signal which is representative for a sample analog signal.
REFERENCES:
patent: 4742550 (1988-05-01), Fette
patent: 4964166 (1990-10-01), Wilson
patent: 4991213 (1991-02-01), Wilson
patent: 5012517 (1991-04-01), Wilson et al.
patent: 5042069 (1991-08-01), Chhatwal
Hermansky et al, Perceptually Based Linear Predictive Analysis of Speech, Mar., 1985, pp. 509-512, vol. 2 of 4 ICASSP 85 IEEE.
Mazor et al, Adaptive Subbands Excited Transform(ASET) Coding Apr., 1986, pp. 3075-3078, vol. 4 of 4, ICASSP '86, IEEE.
Yatsuzuka et al, Hardware Implementation of 9.6/16 KBIT/S APC/MLC Speech Codec and its Applications for Mobile Satellite Communications, Jun., 1987, pp. 418-424 CC-87, IEEE Conference '87 Seattle.
Fette et al, Experiments with a High Quality, Low Complexity 4800 bps Residual Excited LPC (RELP) Vocoder, Apr. 1988, pp. 263-266, vol. 1, ICASSP 88, IEEE.
Schroeder et al, Optimizing Digital Speech Coders by Exploiting Masking Properties, of the Human Ear, Journal Acoustic Soc. of America, Dec., 1979, pp. 1647-1652.
Johnston, Transform Coding of Audio Signals Using Perceptual Noise Criteria, IEEE Journal on Selected Areas of Communication Vo. 6, No. 2, Feb., 1988.
Atal, Predictive Coding of Speech at Low Bit Rates IEEE, Transactions on Communications, vol. 30, No. 4, Apr., 1982.
L.R. Rabiner et al, Chapter 8, Digital Processing of Speech Signals, Prentice Hall, New Jersey, pp. 396-461.
Vary et al, Frequenz, vol. 42, No. 2-3, 1988; pp. 85-93, Sprachcodec Fur Dass Europaische Funkfernsprechnetz.
B. Scharf et al, Handbook of Perception and Human Performance, Chapter 14, pp. 1-43, Wiley, New York, 1986.
P. Chang et al, Fourier Transform Vectors Quantisation for Speech Coding, IEEE Transactions and Communications, vol. Com. 35, No. 10, pp. 1059-1068.
Beranek, "Acoustics", McGraw-Hill Book Company, Inc., 1954, pp. 332-334.
Beerends John Gerard
Muller Frank
van Ravesteijn Robertus Lambertus Adrianus
Knepper David D.
Koninklijke PTT Nederland N.V.
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