US5778335A
Expired / Lapsed
US
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Method and apparatus for efficient multiband celp wideband speech and music coding and decoding
Assignee: University of California
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Filing: 1996-02-26
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Granted: 1998-07-07
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Expires: 2016-02-26
Abstract
Abstract A method of digitally compressing speech and music by use of multiple band ("multiband") fixed excitations stored in codebooks. The use of multiband fixed excitations, along with a coupling method for interconnecting the excitation codebooks and adaptive codebooks and for generating the composite excitation signal, improve the long-term and short-term prediction, and the use of voice-music classification allows the coding structure to be adapted to the statistical character of the audio signal.
Inventors
- 👤 Anil Wamanrao Ubale
- 👤 Allen Gersho
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:40
CPC Classifications
G; G10; G10L; G10L19/00; G10L19/04; G10L19/16; G10L19/18; G10H; G10H1/00; G10H1/02; G10H1/06; G10H1/12; G10H1/125; G10H7/00; G10L19/08; G10L19/12; G10H2210/00; G10H2210/031; G10H2210/046; G10H2240/00; G10H2240/171; G10H2240/201; G10H2240/241; G10H2240/251; G10H2250/00; G10H2250/541; G10H2250/571; G10H2250/581; G10H2250/585; G10L19/002; G10L19/02; G10L19/0204; G10L19/10; G10L2019/0001; G10L2019/0004; G10L2019/0005; G10L25/00; G10L25/78; G10L2025/783
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
169 words
A method for encoding and decoding sound, comprising the steps of: analyzing an input waveform and computing the linear prediction coefficients for a portion of the input waveform; classifying the input waveform as one of a group comprising speech and music; generating a first plurality of codebooks, each having an output, where each codebook is associated with a frequency band; generating at least one first adaptive codebook having an output; coupling the output of the first plurality of codebooks and the output of the at least one first adaptive codebook together to create a composite waveform; synthesis filtering the composite waveform; perceptually weighting the input waveform; perceptually weighting the synthesis filtered composite waveform; differencing the perceptually weighted synthesis filtered composite waveform from the perceptually weighted input waveform to form an output waveform; searching through the first plurality of codebooks and the adaptive codebook to minimize the errors in the output waveform; and decoding the output waveform using a second plurality of codebooks and at least one second adaptive codebook.
Claim 2
Independent Claim
169 words
A method for encoding and decoding sound, comprising the steps of: analyzing an input waveform and computing the linear prediction coefficients for a portion of the input waveform; classifying the input waveform as one of a group comprising speech and music; generating a first plurality of codebooks, each having an output, where each codebook is associated with a frequency band; generating at least one first adaptive codebook having an output; coupling the output of the first plurality of codebooks and the output of the at least one first adaptive codebook together to create a composite waveform; synthesis filtering the composite waveform; perceptually weighting the input waveform; perceptually weighting the synthesis filtered composite waveform; differencing the perceptually weighted synthesis filtered composite waveform from the perceptually weighted input waveform to form an output waveform; searching through the first plurality of codebooks and the adaptive codebook to minimize the errors in the output waveform; and decoding the output waveform using a second plurality of codebooks and at least one second adaptive codebook.
Claim 3
Dependent Claim
24 words
The method of claim 1, further comprising the step of masking an output quantization noise from the output of the first plurality of codebooks.
Claim 4
Dependent Claim
15 words
The method of claim 1, further comprising the step of post-filtering the decoded output waveform.
Claim 5
Independent Claim
196 words
A system to encode and decode sound, comprising: an analyzer to compute linear prediction coefficients for a portion of an input waveform; a classifier for classifying the input waveform as one of a group comprising speech, speech and music, and music; a first plurality of codebooks, each having an output, where each codebook is associated with a frequency band; at least one first adaptive codebook having an output; a first coupler to couple the output of the first plurality of codebooks and the output of the at least one first adaptive codebook together to create a composite waveform; a synthesis filter for filtering the composite waveform; a first perceptual weighting filter for filtering the input waveform; a second perceptual weighting filter for filtering the synthesis filtered composite waveform; a signal combiner for differencing the perceptually weighted synthesis filtered composite waveform from the perceptually weighted input waveform to form an output waveform; selector means for searching through the first plurality of codebooks and the adaptive codebook to minimize the errors in the output waveform; and decoder means for decoding the output waveform, the decoder comprising a second plurality of codebooks and at least one second adaptive codebook.
Claim 6
Independent Claim
196 words
A system to encode and decode sound, comprising: an analyzer to compute linear prediction coefficients for a portion of an input waveform; a classifier for classifying the input waveform as one of a group comprising speech, speech and music, and music; a first plurality of codebooks, each having an output, where each codebook is associated with a frequency band; at least one first adaptive codebook having an output; a first coupler to couple the output of the first plurality of codebooks and the output of the at least one first adaptive codebook together to create a composite waveform; a synthesis filter for filtering the composite waveform; a first perceptual weighting filter for filtering the input waveform; a second perceptual weighting filter for filtering the synthesis filtered composite waveform; a signal combiner for differencing the perceptually weighted synthesis filtered composite waveform from the perceptually weighted input waveform to form an output waveform; selector means for searching through the first plurality of codebooks and the adaptive codebook to minimize the errors in the output waveform; and decoder means for decoding the output waveform, the decoder comprising a second plurality of codebooks and at least one second adaptive codebook.
Claim 7
Dependent Claim
26 words
The system of claim 4, wherein the system further comprises masking means for masking a quantization noise from the output of the first plurality of codebooks.
Claim 8
Dependent Claim
16 words
The system of claim 4, further comprising of post-filtering means for filtering the decoded output waveform.
Claim 9
Independent Claim
88 words
A method for encoding an audio signal, comprising the steps of: generating a multiple band excitation codebook bank and at least one adaptive codebook; coupling the multiple band fixed excitation codebook bank and the at least one adaptive codebook for generating a composite excitation signal, providing a long-term and a short-term prediction signal; classifying as voice or music the composite excitation signal based on the long-term prediction signal and the short-term prediction signal; and adapting the classified composite excitation signal to a statistical character of the audio signal.
Claim 10
Independent Claim
88 words
A method for encoding an audio signal, comprising the steps of: generating a multiple band excitation codebook bank and at least one adaptive codebook; coupling the multiple band fixed excitation codebook bank and the at least one adaptive codebook for generating a composite excitation signal, providing a long-term and a short-term prediction signal; classifying as voice or music the composite excitation signal based on the long-term prediction signal and the short-term prediction signal; and adapting the classified composite excitation signal to a statistical character of the audio signal.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-07-06 | 2002-01-05 | 2002-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-07-06 | 2006-01-05 | 2006-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-07-06 | 2010-01-05 | 2010-07-07 | $7700.00 | Window Closed / Lapsed |