CA2167527A1 - Sub-band coder with differentially encoded scale factors - Google Patents

Sub-band coder with differentially encoded scale factors

Info

Publication number
CA2167527A1
CA2167527A1 CA002167527A CA2167527A CA2167527A1 CA 2167527 A1 CA2167527 A1 CA 2167527A1 CA 002167527 A CA002167527 A CA 002167527A CA 2167527 A CA2167527 A CA 2167527A CA 2167527 A1 CA2167527 A1 CA 2167527A1
Authority
CA
Canada
Prior art keywords
sub
scale factors
differentially encoded
band coder
encoded scale
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA002167527A
Other languages
French (fr)
Other versions
CA2167527C (en
Inventor
Craig Campbell Todd
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dolby Laboratories Licensing Corp
Original Assignee
Craig Campbell Todd
Dolby Laboratories Licensing Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Craig Campbell Todd, Dolby Laboratories Licensing Corporation filed Critical Craig Campbell Todd
Publication of CA2167527A1 publication Critical patent/CA2167527A1/en
Application granted granted Critical
Publication of CA2167527C publication Critical patent/CA2167527C/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10L—SPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
    • G10L19/00—Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
    • G10L19/02—Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis using spectral analysis, e.g. transform vocoders or subband vocoders
    • G10L19/032—Quantisation or dequantisation of spectral components
    • G10L19/035—Scalar quantisation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/66—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission for reducing bandwidth of signals; for improving efficiency of transmission
    • H04B1/667—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission for reducing bandwidth of signals; for improving efficiency of transmission using a division in frequency subbands

Abstract

The invention relates in general to low bit-rate encoding and decoding of information such as audio information. More particularly, the invention relates to method and apparatus for reducing the amount of information required to convey a high-resolution spectral envelope of a signal. A sub-band encoder prepares an estimate of an input signal spectral envelope by splitting the input signal into frequency sub-band signals, generates a scaled representation of the sub-band signals comprising scaling factors and scaled values, generates a differential coded representation of the scaling factors, and assembles the differential coded representation and scaled values into an encoded signal.
CA002167527A 1993-08-31 1994-08-30 Sub-band coder with differentially encoded scale factors Expired - Lifetime CA2167527C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US08/115,513 1993-08-31
US08/115,513 US5581653A (en) 1993-08-31 1993-08-31 Low bit-rate high-resolution spectral envelope coding for audio encoder and decoder
PCT/US1994/009736 WO1995006984A1 (en) 1993-08-31 1994-08-30 Sub-band coder with differentially encoded scale factors

Publications (2)

Publication Number Publication Date
CA2167527A1 true CA2167527A1 (en) 1995-03-09
CA2167527C CA2167527C (en) 2004-05-18

Family

ID=22361888

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002167527A Expired - Lifetime CA2167527C (en) 1993-08-31 1994-08-30 Sub-band coder with differentially encoded scale factors

Country Status (11)

Country Link
US (1) US5581653A (en)
EP (1) EP0716787B1 (en)
JP (1) JP3940165B2 (en)
AT (1) ATE147910T1 (en)
AU (1) AU685505B2 (en)
CA (1) CA2167527C (en)
DE (1) DE69401517T2 (en)
DK (1) DK0716787T3 (en)
ES (1) ES2097061T3 (en)
SG (1) SG48278A1 (en)
WO (1) WO1995006984A1 (en)

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RU2454738C2 (en) * 2008-08-29 2012-06-27 Сони Корпорейшн Frequency band extension apparatus and method, encoding apparatus and method, decoding apparatus and method, and program

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Also Published As

Publication number Publication date
DK0716787T3 (en) 1997-06-23
AU685505B2 (en) 1998-01-22
DE69401517D1 (en) 1997-02-27
JP3940165B2 (en) 2007-07-04
EP0716787B1 (en) 1997-01-15
SG48278A1 (en) 1998-04-17
CA2167527C (en) 2004-05-18
ATE147910T1 (en) 1997-02-15
US5581653A (en) 1996-12-03
ES2097061T3 (en) 1997-03-16
JPH09502314A (en) 1997-03-04
AU7676594A (en) 1995-03-22
WO1995006984A1 (en) 1995-03-09
DE69401517T2 (en) 1997-06-12
EP0716787A1 (en) 1996-06-19

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