Patent US5488665A successfully refreshed from Google Patents.
US5488665A
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Multi-channel perceptual audio compression system with encoding mode switching among matrixed channels
Assignee: AT&T Inc
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Filing: 1993-11-23
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Granted: 1996-01-30
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Expires: 2013-11-23
Abstract
Abstract A five-channel perceptual audio compression system which encodes five matrixed channels switches among a fourteen encoding modes each utilizing a respective different set of matrixed channels. Six of the modes are for encoding the three front channels and eight of the modes are for encoding the two back channels. A number of the modes have as at least one of their respective matrixed channels a matrixed channel which is a function of a) one of the input channels or a sum or difference of two of them, and b) a predicted value of a).
Inventors
- 👤 James D. Johnston
- 👤 Deepen Sinha
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:59
CPC Classifications
H; H03; H03M; H03M7/00; H04; H04S; H04S3/00; H04S3/02; H04B; H04B1/00; H04B1/66; H04B1/665
Claims Analysis
Total Claims: 48
Claim 1
Independent Claim
114 words
A method of perceptually encoding an audio signal comprising a set of input channels, the method comprising the steps of generating a set of matrixed channels in response to said input channels, and perceptually encoding said matrixed channels, said perceptually encoding step including selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding; at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a).
Claim 2
Independent Claim
114 words
A method of perceptually encoding an audio signal comprising a set of input channels, the method comprising the steps of generating a set of matrixed channels in response to said input channels, and perceptually encoding said matrixed channels, said perceptually encoding step including selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding; at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a).
Claim 3
Independent Claim
102 words
A method of perceptually encoding an audio signal comprising a set of input channels, the method comprising the steps of generating a set of matrixed channels in response to said input channels. perceptually encoding said matrixed channels, at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), and alternatively applying to an output a) said perceptually encoded matrixed channels and b) a perceptual encoding of said input channels.
Claim 4
Independent Claim
102 words
A method of perceptually encoding an audio signal comprising a set of input channels, the method comprising the steps of generating a set of matrixed channels in response to said input channels. perceptually encoding said matrixed channels, at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), and alternatively applying to an output a) said perceptually encoded matrixed channels and b) a perceptual encoding of said input channels.
Claim 5
Independent Claim
107 words
A method of perceptually encoding an audio signal comprising a set of input channels, the method comprising the steps of generating a set of matrixed channels in response to said input channels. perceptually encoding said matrixed channels, at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), and alternatively applying to a communication channel or a storage medium a) said perceptually encoded matrixed channels and b) a perceptual encoding of said input channels.
Claim 6
Independent Claim
107 words
A method of perceptually encoding an audio signal comprising a set of input channels, the method comprising the steps of generating a set of matrixed channels in response to said input channels. perceptually encoding said matrixed channels, at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), and alternatively applying to a communication channel or a storage medium a) said perceptually encoded matrixed channels and b) a perceptual encoding of said input channels.
Claim 7
Independent Claim
140 words
A method of perceptually encoding an audio signal comprising a set of input channels, the method comprising the steps of generating a set of matrixed channels in response to said input channels, and perceptually encoding said matrixed channels, at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), wherein in said audio signal, said input channels are represented in the frequency domain and wherein said generating step comprises the step of generating said set of matrixed channels from said input channels in such a way that each of said matrixed channels is represented, for each of a series of time domain blocks, by frequency spectrum lines.
Claim 8
Independent Claim
140 words
A method of perceptually encoding an audio signal comprising a set of input channels, the method comprising the steps of generating a set of matrixed channels in response to said input channels, and perceptually encoding said matrixed channels, at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), wherein in said audio signal, said input channels are represented in the frequency domain and wherein said generating step comprises the step of generating said set of matrixed channels from said input channels in such a way that each of said matrixed channels is represented, for each of a series of time domain blocks, by frequency spectrum lines.
Claim 9
Dependent Claim
50 words
The invention of claim 4 wherein said frequency spectrum lines are divided into a plurality of coder bands and wherein the magnitudes of the frequency spectrum lines of each coder band are represented by values that are quantized as a function of a noise threshold associated with that coder band.
Claim 10
Dependent Claim
139 words
Apparatus for processing an audio signal comprising a set of input channels, said apparatus comprising means for perceptually encoding one of a predetermined plurality of sets of matrixed channels generated in response to said input channels, said perceptually encoding means including selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding, the channels of an individual one of said sets of matrixed channels being said input channels and the channels of others of said sets of matrixed channels including at least an individual one sum of, or the difference between, two of them, and b) a prediction of a), and means for applying the perceptually encoded matrixed channels to a selected one of a) a communications channel, and b) a storage medium,
Claim 11
Dependent Claim
139 words
Apparatus for processing an audio signal comprising a set of input channels, said apparatus comprising means for perceptually encoding one of a predetermined plurality of sets of matrixed channels generated in response to said input channels, said perceptually encoding means including selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding, the channels of an individual one of said sets of matrixed channels being said input channels and the channels of others of said sets of matrixed channels including at least an individual one sum of, or the difference between, two of them, and b) a prediction of a), and means for applying the perceptually encoded matrixed channels to a selected one of a) a communications channel, and b) a storage medium,
Claim 12
Dependent Claim
167 words
Apparatus for processing an audio signal comprising a set of input channels, said apparatus comprising means for perceptually encoding one of a predetermined plurality of sets of matrixed channels generated in response to said input channels, the channels of an individual one of said sets of matrixed channels being said input channels and the channels of others of said sets of matrixed channels including at least an individual one sum of, or the difference between, two of them, and b) a prediction of a), and means for applying the perceptually encoded matrixed channels to a selected one of a) a communications channel, and b) a storage medium, wherein in said audio signal, said input channels are represented for each of a series of time domain blocks, by frequency spectrum lines divided into a plurality of coder bands, the magnitudes of the frequency spectrum lines of each coder band being represented by values that are quantized as a function of a noise threshold associated with that coder band.
Claim 13
Dependent Claim
167 words
Apparatus for processing an audio signal comprising a set of input channels, said apparatus comprising means for perceptually encoding one of a predetermined plurality of sets of matrixed channels generated in response to said input channels, the channels of an individual one of said sets of matrixed channels being said input channels and the channels of others of said sets of matrixed channels including at least an individual one sum of, or the difference between, two of them, and b) a prediction of a), and means for applying the perceptually encoded matrixed channels to a selected one of a) a communications channel, and b) a storage medium, wherein in said audio signal, said input channels are represented for each of a series of time domain blocks, by frequency spectrum lines divided into a plurality of coder bands, the magnitudes of the frequency spectrum lines of each coder band being represented by values that are quantized as a function of a noise threshold associated with that coder band.
Claim 14
Independent Claim
181 words
A method for processing a perceptually encoded audio signal, said perceptually encoded audio signal having been generated by generating a set of matrixed channels in response to a set of input channels; perceptually encoding said matrixed channels wherein said perceptually encoding includes selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding; and applying said perceptually encoded matrixed channels to a communication channel or a storage medium, said set of matrixed channels comprising a selected one of i) said input channels, and ii) a set of matrixed channels in which at least an individual one of the matrixed channels is a function of a) an individual one of said input channels or the sum of; or the difference between, two of them, and b) a prediction of a), said method comprising the steps of receiving said perceptually encoded matrixed channels from said communications channel or storage medium, decoding the received perceptually encoded matrixed channels, and recovering said input channels from the decoded matrixed channels.
Claim 15
Independent Claim
181 words
A method for processing a perceptually encoded audio signal, said perceptually encoded audio signal having been generated by generating a set of matrixed channels in response to a set of input channels; perceptually encoding said matrixed channels wherein said perceptually encoding includes selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding; and applying said perceptually encoded matrixed channels to a communication channel or a storage medium, said set of matrixed channels comprising a selected one of i) said input channels, and ii) a set of matrixed channels in which at least an individual one of the matrixed channels is a function of a) an individual one of said input channels or the sum of; or the difference between, two of them, and b) a prediction of a), said method comprising the steps of receiving said perceptually encoded matrixed channels from said communications channel or storage medium, decoding the received perceptually encoded matrixed channels, and recovering said input channels from the decoded matrixed channels.
Claim 16
Independent Claim
168 words
A method for processing a perceptually encoded audio signal, said perceptually encoded audio signal having been generated by generating a set of mat fixed channels in response to a set of input channels; perceptually encoding said matrixed channels; and applying said perceptually encoded matrixed channels to a communication channel or a storage medium, said set of matrixed channels comprising a selected one of i) said input channels, and ii) a set of matrixed channels in which at least an individual one of the matrixed channels is a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), said method comprising the steps of receiving said perceptually encoded matrixed channels from said communications channel or storage medium, decoding the received perceptually encoded matrixed channels, and recovering said input channels from the decoded matrixed channels and determining how said set of matrixed channels was generated in response to said set of input channels.
Claim 17
Independent Claim
168 words
A method for processing a perceptually encoded audio signal, said perceptually encoded audio signal having been generated by generating a set of mat fixed channels in response to a set of input channels; perceptually encoding said matrixed channels; and applying said perceptually encoded matrixed channels to a communication channel or a storage medium, said set of matrixed channels comprising a selected one of i) said input channels, and ii) a set of matrixed channels in which at least an individual one of the matrixed channels is a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), said method comprising the steps of receiving said perceptually encoded matrixed channels from said communications channel or storage medium, decoding the received perceptually encoded matrixed channels, and recovering said input channels from the decoded matrixed channels and determining how said set of matrixed channels was generated in response to said set of input channels.
Claim 18
Dependent Claim
166 words
Apparatus for processing a perceptually encoded audio signal, said perceptually encoded audio signal having been generated by generating a set of matrixed channels in response to a set of input channels; perceptually encoding said matrixed channels wherein said perceptually encoding includes selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding; and applying the perceptually encoded matrixed channels to a communication channel or a storage medium; at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), said apparatus comprising means for receiving said perceptually encoded matrixed channels from said communications channel or storage medium, means for decoding the received perceptually encoded matrixed channels, and means for recovering said input channels from the decoded matrixed channels.
Claim 19
Dependent Claim
166 words
Apparatus for processing a perceptually encoded audio signal, said perceptually encoded audio signal having been generated by generating a set of matrixed channels in response to a set of input channels; perceptually encoding said matrixed channels wherein said perceptually encoding includes selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding; and applying the perceptually encoded matrixed channels to a communication channel or a storage medium; at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), said apparatus comprising means for receiving said perceptually encoded matrixed channels from said communications channel or storage medium, means for decoding the received perceptually encoded matrixed channels, and means for recovering said input channels from the decoded matrixed channels.
Claim 20
Dependent Claim
152 words
Apparatus for processing a perceptually encoded audio signal, said perceptually encoded audio signal having been generated by generating a set of matrixed channels in response to a set of input channels; perceptually encoding said matrixed channels; and applying the perceptually encoded matrixed channels to a communication channel or a storage medium; at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), said apparatus comprising means for receiving said perceptually encoded matrixed channels from said communications channel or storage medium, means for decoding the received perceptually encoded matrixed channels, and means for recovering said input channels from the decoded matrixed channels and determining how said set of matrixed channels was generated in response to said set of input channels.
Claim 21
Dependent Claim
152 words
Apparatus for processing a perceptually encoded audio signal, said perceptually encoded audio signal having been generated by generating a set of matrixed channels in response to a set of input channels; perceptually encoding said matrixed channels; and applying the perceptually encoded matrixed channels to a communication channel or a storage medium; at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a), said apparatus comprising means for receiving said perceptually encoded matrixed channels from said communications channel or storage medium, means for decoding the received perceptually encoded matrixed channels, and means for recovering said input channels from the decoded matrixed channels and determining how said set of matrixed channels was generated in response to said set of input channels.
Claim 22
Dependent Claim
124 words
Apparatus in which is stored information representing a perceptually encoded audio signal comprising a set of input channels, said perceptually encoded audio signal having been generated by the steps of generating a set of matrixed channels in response to said input channels, and perceptually encoding said matrixed channels, said perceptually encoding step including selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding, at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a).
Claim 23
Dependent Claim
124 words
Apparatus in which is stored information representing a perceptually encoded audio signal comprising a set of input channels, said perceptually encoded audio signal having been generated by the steps of generating a set of matrixed channels in response to said input channels, and perceptually encoding said matrixed channels, said perceptually encoding step including selecting noise threshold values based upon noise masking criteria and using said noise threshold values to control the coarseness of quantizing said audio signal during said encoding, at least an individual one of the matrixed channels of said set of matrixed channels being a function of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a).
Claim 24
Dependent Claim
96 words
Apparatus in which is stored information representing a perceptually encoded audio signal comprising a set of input channels, said perceptually encoded audio signal having been generated by the steps of generating a set of matrixed channels in response to said input channels, and perceptually encoding said input channels alternatively with said matrixed channels, at least an individual one of the matrixed channels of said set of matrixed channels being a function,of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a).
Claim 25
Dependent Claim
96 words
Apparatus in which is stored information representing a perceptually encoded audio signal comprising a set of input channels, said perceptually encoded audio signal having been generated by the steps of generating a set of matrixed channels in response to said input channels, and perceptually encoding said input channels alternatively with said matrixed channels, at least an individual one of the matrixed channels of said set of matrixed channels being a function,of a) an individual one of said input channels or the sum of, or the difference between, two of them, and b) a prediction of a).
Claim 26
Dependent Claim
35 words
The invention of claim 1 or claim 6 or claim 8 or claim 10 or claim 12 wherein said individual one of said matrixed channels is a function of the difference between a) and b).
Claim 27
Dependent Claim
17 words
The invention of claim 2 wherein said set of input channels includes left, right and center channels.
Claim 28
Dependent Claim
72 words
The invention of claim 156 wherein a first one of said matrixed channels is a function of said left channel and a prediction of said left channel; wherein a second one of said matrixed channels is a function of said right channel and a prediction of said right channel; and wherein a third one of said matrixed channels is said center channel; each said prediction being a function of said center channel.
Claim 29
Dependent Claim
21 words
The invention of claim 16 wherein each said prediction is a function of a perceptually encoded version of said center channel.
Claim 30
Dependent Claim
31 words
The invention of claim 16 wherein each said prediction is a function of the product of a) a perceptually encoded version of said center channel, with b) a respective prediction coefficient.
Claim 31
Dependent Claim
63 words
The invention of claim 15 wherein a first one of said matrixed channels is said left channel; wherein a second one of said matrixed channels is said right channel; and wherein a third one of said matrixed channels is a function of said center channel and a prediction of said center channel, that prediction being a function of said left and right channels.
Claim 32
Dependent Claim
21 words
The invention of claim 19 wherein said prediction is a function of perceptually encoded versions of said left and right channels.
Claim 33
Dependent Claim
54 words
The invention of claim 19 wherein said prediction is a function of the product of a) a perceptually encoded version of said left channel with b) a respective prediction coefficient, and is further a function of the product of a) a perceptually encoded version of said right channel, with b) a respective prediction coefficient.
Claim 34
Dependent Claim
58 words
The invention of claim 15 wherein a first one of said matrixed channels is a function of the sum of said left and right channels; wherein a second one of said matrixed channels is a function of the difference between said left and right channels; and wherein a third one of said matrixed channels is said center channel.
Claim 35
Dependent Claim
103 words
The invention of claim 15 wherein a first one of said matrixed channels is a function of a sum channel and a prediction of said sum channel; wherein a second one of said matrixed channels is a function of a difference channel and a prediction of said difference channel; and wherein a third one of said matrixed channels is said center channel; said sum channel being a function of the sum of said left and right channels, said difference channel being a function of the difference between said left and right channels, and each said prediction being a function of said center channel.
Claim 36
Dependent Claim
21 words
The invention of claim 23 wherein each said prediction is a function of a perceptually encoded version of said center channel.
Claim 37
Dependent Claim
31 words
The invention of claim 23 wherein each said prediction is a function of the product of a) a perceptually encoded version of said center channel, with b) a respective prediction coefficient.
Claim 38
Dependent Claim
94 words
The invention of claim 15 wherein a first one of said matrixed channels is a sum channel; wherein a second one of said matrixed channels is a difference channel; and wherein a third one of said matrixed channels is a function of said center channel and a prediction of said center channel; said sum channel being a function of the sum of said left and right channels, said difference channel being a function of the difference between said left and right channels, and said prediction being a function of said left and right channels.
Claim 39
Dependent Claim
21 words
The invention of claim 26 wherein said prediction is a function of perceptually encoded versions of said left and right channels.
Claim 40
Dependent Claim
54 words
The invention of claim 26 wherein said prediction is a function of the product of a) a perceptually encoded version of said left channel with b) a respective prediction coefficient, and is further a function of the product of a) a perceptually encoded version of said right channel, with b) a respective prediction coefficient.
Claim 41
Dependent Claim
19 words
The invention of claim 15 wherein said set of input channels further includes left surround and right surround channels.
Claim 42
Dependent Claim
54 words
The invention of claim 29 wherein an individual one of said matrixed channels is a function of said left surround channel and a prediction of said left surround channel, and wherein a further one of said matrixed channels is a function of said right surround channel and a prediction of said right surround channel.
Claim 43
Dependent Claim
31 words
The invention of claim 30 wherein said left surround channel prediction and said right surround channel prediction are respective functions of one or more of said left, right and center channels.
Claim 44
Dependent Claim
35 words
The invention of claim 30 wherein said left surround channel prediction and said right surround channel prediction are respective functions of perceptually encoded versions of one or more of said left, right and center channels.
Claim 45
Dependent Claim
50 words
The invention of claim 29 wherein an individual one of said matrixed channels is a function of the sum of said left surround and right surround channels; and wherein a further one of said matrixed channels is a function of the difference between said left surround and right surround channels.
Claim 46
Dependent Claim
91 words
The invention of claim 29 wherein an individual one of said matrixed channels is a function of a sum surround channel and a prediction of said sum surround channel; and wherein a further one of said matrixed channels is a function of a difference surround channel and a prediction of said difference surround channel; said sum surround channel being a function of the sum of said left surround and right surround channels, and said difference surround channel being a function of the difference between said left surround and right surround channels.
Claim 47
Dependent Claim
31 words
The invention of claim 34 wherein said sum surround channel prediction and said difference surround channel prediction are respective functions of one or more of said left, right and center channels.
Claim 48
Dependent Claim
35 words
The invention of claim 34 wherein said sum surround channel prediction and said difference surround channel prediction are respective functions of perceptually encoded versions of one or more of said left, right and center channels.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-01-29 | 1999-07-31 | 2000-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-01-29 | 2003-07-31 | 2004-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-01-29 | 2007-07-31 | 2008-01-30 | $7700.00 | Window Closed / Lapsed |