US5694332A
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MPEG audio decoding system with subframe input buffering
Assignee: Avago Technologies International Sales Pte Ltd
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Filing: 1994-12-13
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Granted: 1997-12-02
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Expires: 2014-12-13
Abstract
Abstract A Motion Picture Experts Group (MPEG) video/audio data bitstream comprises frames of encoded audio data, each of which includes a plurality of integrally encoded subframes, which are decoded by an audio decoder for presentation. An input buffer arrangement includes first and second buffer memories which each have a capacity to store one subframe. The first and second buffer memories are used alternatingly, with one storing a subframe of input data while another subframe is being read out of the other. A third buffer memory, which has a capacity to store at least one subframe, is provided upstream of the first and second buffer memories to prevent the first and second buffer memories from overflowing or underflowing.
Inventors
- 👤 Greg Maturi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:38
CPC Classifications
G; G10; G10L; G10L19/00; G10L19/02; G10L19/0204; G10L19/0208
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
114 words
A decoding system for decoding a data bitstream including frames of data, each frame including a plurality of subframes of integrally encoded data, comprising: a first buffer memory having a capacity for storing at least one subframe; a second buffer memory having a capacity for storing at least one subframe; controller means for alternatingly storing subframes in the first buffer memory and the second buffer memory; and decoding means for reading out and decoding a subframe from the first buffer memory while the controller means stores a subframe in the second buffer memory, and reading and decoding a subframe from the second buffer while a subframe is being stored in the first buffer memory.
Claim 2
Dependent Claim
114 words
A decoding system for decoding a data bitstream including frames of data, each frame including a plurality of subframes of integrally encoded data, comprising: a first buffer memory having a capacity for storing at least one subframe; a second buffer memory having a capacity for storing at least one subframe; controller means for alternatingly storing subframes in the first buffer memory and the second buffer memory; and decoding means for reading out and decoding a subframe from the first buffer memory while the controller means stores a subframe in the second buffer memory, and reading and decoding a subframe from the second buffer while a subframe is being stored in the first buffer memory.
Claim 3
Dependent Claim
21 words
A system as in claim 1, further comprising a third buffer memory disposed upstream of the first and second buffer memories.
Claim 4
Dependent Claim
21 words
A system as in claim 2, in which the third buffer memory has a capacity for storing at least one subframe.
Claim 5
Dependent Claim
74 words
A system as in claim 1, in which the controller means comprises: computing means for computing a number of bits in one subframe; counting means for counting bits of said bitstream; and toggling means for toggling the first buffer memory between a read mode and a write mode and toggling the second buffer memory between said write mode and said read mode respectively in response to the counter means counting said number of bits.
Claim 6
Dependent Claim
54 words
A system as in claim 4, in which: the counting means loads said number of bits from the computing means in response to a reset condition, and is decremented by counting said bits; and the toggling means toggles the first and second buffer memories in response to the counting means being decremented to zero.
Claim 7
Dependent Claim
33 words
A system as in claim 5, in which each of the first and second buffer memories generates said reset condition in response to a subframe being read out thereof by the decoding means.
Claim 8
Dependent Claim
23 words
A system as in claim 5, in which the decoding means generates said reset condition in response to completion of decoding a subframe.
Claim 9
Dependent Claim
32 words
A system as in claim 4, in which: each frame of data further includes information indicating said number of bits; and the computing means computes said number of bits from said information.
Claim 10
Dependent Claim
39 words
A system as in claim 4, in which: said bitstream is an MPEG bitstream, comprising a header for each frame including audio subband allocation data; and the computing means computes said number of bits from said subband allocation data.
Claim 11
Dependent Claim
40 words
A system as in claim 9, in which the computing means comprises: header decoding means for decoding said header to obtain said subband allocation data; and summing means for summing said subband allocation data to obtain said number of bits.
Claim 12
Dependent Claim
25 words
A system as in claim 1, in which the first and second buffer memories each have a capacity for storing no more than one subframe.
Claim 13
Independent Claim
123 words
A method of decoding an MPEG bitstream including frames of data, each frame including a plurality of subframes of integrally encoded audio subband sample data, comprising the steps of: (a) providing a first buffer memory having a capacity for storing at least one subframe; (b) providing a second buffer memory having a capacity for storing at least one subframe; (c) alternatingly storing substantially one subframe at a time in the first buffer memory and the second buffer memory; and (d) reading out and decoding a subframe from the first buffer memory while a subframe is being stored in the second buffer memory, and reading and decoding a subframe from the second buffer while a subframe is being stored in the first buffer memory.
Claim 14
Independent Claim
123 words
A method of decoding an MPEG bitstream including frames of data, each frame including a plurality of subframes of integrally encoded audio subband sample data, comprising the steps of: (a) providing a first buffer memory having a capacity for storing at least one subframe; (b) providing a second buffer memory having a capacity for storing at least one subframe; (c) alternatingly storing substantially one subframe at a time in the first buffer memory and the second buffer memory; and (d) reading out and decoding a subframe from the first buffer memory while a subframe is being stored in the second buffer memory, and reading and decoding a subframe from the second buffer while a subframe is being stored in the first buffer memory.
Claim 15
Dependent Claim
41 words
A method as in claim 12, further comprising the step, performed prior to step (c), of: (e) providing a third buffer memory upstream of the first and second buffer memories; and (f) using the third buffer memory to accumulate said data.
Claim 16
Dependent Claim
26 words
A method as in claim 13, in which step (e) comprises providing the third buffer memory as having a capacity for storing at least one subframe.
Claim 17
Dependent Claim
70 words
A method as in claim 12, in which step (c) comprises the substeps of: (e) computing a number of bits in one subframe; (f) counting bits of said bitstream; and (g) toggling the first buffer memory between a read mode and a write mode and toggling the second buffer memory between said write mode and said read mode respectively after said number of bits has been counted in step (f).
Claim 18
Dependent Claim
32 words
A method as in claim 15, in which: each frame of data further includes information indicating said number of bits; and step (e) comprises computing said number of bits from said information.
Claim 19
Dependent Claim
31 words
A method as in claim 15, in which: each frame comprises a header including subband allocation data; and step (e) comprises computing said number of bits from said subband allocation data.
Claim 20
Dependent Claim
37 words
A method as in claim 17, in which step (e) comprises the substeps of: (h) decoding said header to obtain said subband allocation data; and (i) summing said subband allocation data to obtain said number of bits.
Claim 21
Dependent Claim
43 words
A method as in claim 12, in which: step (a) comprises providing a first buffer memory having a capacity for storing no more than one subframe; and step (b) comprises providing a second buffer memory having a capacity for storing substantially one subframe.
Claim 22
Dependent Claim
111 words
A decoding system for decoding an MPEG input data bitstream including frames of data, each frame including a plurality of subframes of integrally encoded audio subband sample data, comprising: a first buffer memory having a capacity for storing at least one subframe; a second buffer memory having a capacity for storing at least one subframe; a third buffer memory disposed upstream of the first and second buffer memories; controller means for alternatingly storing subframes in the first buffer memory and the second buffer memory; and decoding means for reading out and decoding a subframe from the first buffer memory while the controller means stores another subframe in the second buffer memory.
Claim 23
Dependent Claim
111 words
A decoding system for decoding an MPEG input data bitstream including frames of data, each frame including a plurality of subframes of integrally encoded audio subband sample data, comprising: a first buffer memory having a capacity for storing at least one subframe; a second buffer memory having a capacity for storing at least one subframe; a third buffer memory disposed upstream of the first and second buffer memories; controller means for alternatingly storing subframes in the first buffer memory and the second buffer memory; and decoding means for reading out and decoding a subframe from the first buffer memory while the controller means stores another subframe in the second buffer memory.
Claim 24
Dependent Claim
21 words
A system as in claim 20, in which the third buffer memory has a capacity for storing at least one subframe.
Claim 25
Dependent Claim
74 words
A system as in claim 20, in which the controller means comprises: computing means for computing a number of bits in one subframe; counting means for counting bits of said bitstream; and toggling means for toggling the first buffer memory between a read mode and a write mode and toggling the second buffer memory between said write mode and said read mode respectively in response to the counter means counting said number of bits.
Claim 26
Dependent Claim
54 words
A system as in claim 22, in which: the counting means loads said number of bits from the computing means in response to a reset condition, and is decremented by counting said bits; and the toggling means toggles the first and second buffer memories in response to the counting means being decremented to zero.
Claim 27
Dependent Claim
33 words
A system as in claim 23, in which each of the first and second buffer memories generates said reset condition in response to a subframe being read out thereof by the decoding means.
Claim 28
Dependent Claim
34 words
A system as in claim 24, in which: said bitstream comprises a header for each frame including subband allocation data; and the computing means computes said number of bits from said subband allocation data.
Claim 29
Dependent Claim
40 words
A system as in claim 25, in which the computing means comprises: header decoding means for decoding said header to obtain said subband allocation data; and summing means for summing said subband allocation data to obtain said number of bits.
Claim 30
Dependent Claim
23 words
A system as in claim 23, in which the decoding means generates said reset condition in response to completion of decoding a subframe.
Claim 31
Dependent Claim
32 words
A system as in claim 22, in which: each frame of data further includes information indicating said number of bits; and the computing means computes said number of bits from said information.
Claim 32
Dependent Claim
25 words
A system as in claim 20, in which the first and second buffer memories each have a capacity for storing no more than one subframe.
References Cited (Backward Citations)
US4394774A
Cited
US4660079A
Cited
US5202761A
Cited
US5351090A
Cited
US5386233A
Cited
US5446839A
Cited
US5351092A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-12-01 | 2001-06-02 | 2001-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-12-01 | 2005-06-02 | 2005-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-12-01 | 2009-06-02 | 2009-12-02 | $7700.00 | Window Closed / Lapsed |