WO2008100385A4 - Embedded silence and background noise compression - Google Patents

Embedded silence and background noise compression Download PDF

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Publication number
WO2008100385A4
WO2008100385A4 PCT/US2008/001356 US2008001356W WO2008100385A4 WO 2008100385 A4 WO2008100385 A4 WO 2008100385A4 US 2008001356 W US2008001356 W US 2008001356W WO 2008100385 A4 WO2008100385 A4 WO 2008100385A4
Authority
WO
WIPO (PCT)
Prior art keywords
speech signal
narrowband
inactive
speech
signal
Prior art date
Application number
PCT/US2008/001356
Other languages
French (fr)
Other versions
WO2008100385A2 (en
WO2008100385A3 (en
Inventor
Eyal Shlomot
Yang Gao
Adil Benyassine
Original Assignee
Mindspeed Tech Inc
Eyal Shlomot
Yang Gao
Adil Benyassine
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 Mindspeed Tech Inc, Eyal Shlomot, Yang Gao, Adil Benyassine filed Critical Mindspeed Tech Inc
Priority to AT08725056T priority Critical patent/ATE484053T1/en
Priority to JP2009549588A priority patent/JP5096498B2/en
Priority to CN2008800047744A priority patent/CN101606196B/en
Priority to EP08725056A priority patent/EP2118891B1/en
Priority to DE602008002902T priority patent/DE602008002902D1/en
Publication of WO2008100385A2 publication Critical patent/WO2008100385A2/en
Publication of WO2008100385A3 publication Critical patent/WO2008100385A3/en
Publication of WO2008100385A4 publication Critical patent/WO2008100385A4/en

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
    • G10L19/04—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 predictive techniques
    • G10L19/16—Vocoder architecture
    • G10L19/18—Vocoders using multiple modes
    • G10L19/24—Variable rate codecs, e.g. for generating different qualities using a scalable representation such as hierarchical encoding or layered encoding
    • 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
    • G10L19/012—Comfort noise or silence coding
    • 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
    • G10L19/0204—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 using subband decomposition
    • G10L19/0208—Subband vocoders

Abstract

There is provided a method for use by a speech encoder to encode an input speech signal. The method comprises receiving the input speech signal; determining whether the input speech signal includes an active speech signal or an inactive speech signal; low-pass filtering the inactive speech signal to generate a narrowband inactive speech signal; high-pass filtering the inactive speech signal to generate a high-band inactive speech signal; encoding the narrowband inactive speech signal using a narrowband inactive speech encoder to generate an encoded narrowband inactive speech; generating a low-to-high auxiliary signal by the narrowband inactive speech encoder based on the narrowband inactive speech signal; encoding the high-band inactive speech signal using a wideband inactive speech encoder to generate an encoded wideband inactive speech based on the low-to-high auxiliary signal from the narrowband inactive speech encoder; and transmitting the encoded narrowband inactive speech and the encoded wideband inactive speech.

Claims

AMENDED CLAIMS [received by the International Bureau on 25 February 2009 (25.02.09)]
1. A method for use by a speech encoder to encode an input speech signal, the method comprising receiving the input speech signal; determining whether the input speech signal includes an active speech signal or an inactive speech signal; low-pass filtering the inactive speech signal to generate a narrowband inactive speech signal; high-pass filtering the inactive speech signal to generate a high-band inactive speech signal; encoding the narrowband inactive speech signal using a narrowband inactive speech encoder to generate an encoded narrowband inactive speech; generating a first auxiliary signal by the narrowband inactive speech encoder based on the narrowband inactive speech signal; encoding the high-band inactive speech signal using a wideband inactive speech encoder to generate an encoded wideband inactive speech based on the first auxiliary signal from the narrowband inactive speech encoder; transmitting the encoded narrowband inactive speech and the encoded wideband inactive speech.
2. The method of claim 1 further comprising: generating a second auxiliary signal by the wideband inactive speech encoder based on the high-band inactive speech signal; wherein the narrowband inactive speech encoder encodes the narrowband inactive speech signal based on the second auxiliary signal from the wideband inactive speech encoder.
3. The method of claim 1, wherein the transmitting includes a discontinuous transmission (DTX) scheme.
4. A method for use by a speech encoder to encode an input speech signal, the method comprising receiving the input speech signal; determining whether the input speech signal includes an active speech signal or an inactive speech signal; low-pass filtering the inactive speech signal to generate a narrowband inactive speech signal; high-pass filtering the inactive speech signal to generate a high-band inactive speech signal;
25 encoding the narrowband inactive speech signal in accordance with ITU-T G.729 Annex B Recommendation to generate a G.729B encoded narrowband inactive speech; encoding the high-band inactive speech signal to generate an encoded wideband inactive speech; transmitting the G.729B encoded narrowband inactive speech as a G.729B bitstream; and transmitting the encoded wideband inactive speech as a wideband base layer bitstream following the G.729B bitstream.
5. The method of claim 4 further comprising: encoding the narrowband inactive speech signal to generate an enhanced narrowband base layer bitstream; transmitting the enhanced narrowband base layer bitstream following the wideband base layer bitstream.
6. The method of claim 5 further comprising: encoding the high-band inactive speech signal to generate an enhanced wideband base layer bitstream; transmitting the enhanced wideband base layer bitstream following the enhanced narrowband base layer bitstream.
7. The method of claim 4 further comprising: encoding the high-band inactive speech signal to generate an enhanced wideband base layer bitstream; transmitting the wideband narrowband base layer bitstream following the wideband base layer bitstream.
8. The method of claim 7 further comprising: encoding the narrowband inactive speech signal to generate an enhanced narrowband base layer bitstream; transmitting the enhanced narrowband base layer bitstream following the enhanced wideband base layer bitstream.
9. A method for use by a speech decoder to decode a decoded speech signal, the method comprising receiving the decoded speech signal; determining whether the decoded speech signal includes an active decoded speech signal or an inactive decoded speech signal; decoding the active decoded speech signal as an embedded bitstream using a narrowband decoder and a wideband decoder to generated narrowband active speech parameters and wideband active speech parameters; decoding the inactive decoded speech signal as narrowband bitstream to generate narrowband inactive speech parameters; applying bandwidth extension to narrowband inactive speech parameters to generate wideband inactive speech parameters using the narrowband active speech parameters and the wideband active speech parameters.
10. A method for use by a speech encoder to encode an input speech signal, the method comprising receiving the input speech signal; low-pass filtering the speech signal to generate a narrowband speech signal; high-pass filtering the speech signal to generate a high-band speech signal; determining whether the narrowband input speech signal includes an active speech signal or an inactive speech signal; encoding the narrowband speech signal using a narrowband inactive speech encoder to generate an encoded narrowband inactive speech if the determining determines that the narrowband input speech signal includes the inactive speech signal; encoding the high-band speech signal using a wideband inactive speech encoder to generate an encoded wideband inactive speech if the determining determines that the narrowband input speech signal includes the inactive speech signal; transmitting the encoded narrowband inactive speech and the encoded wideband inactive speech.
11. The method of claim 10 further comprising: generating a second auxiliary signal by the wideband inactive speech encoder based on the high-band speech signal; wherein the narrowband inactive speech encoder encodes the narrowband speech signal based on the second auxiliary signal from the wideband inactive speech encoder.
12. The method of claim 10 further comprising: generating a first auxiliary signal by the narrowband inactive speech encoder based on the narrowband speech signal; wherein the wideband inactive speech encoder encodes the wideband speech signal based on the first auxiliary signal from the narrowband inactive speech encoder.
27
13. The method of claim 10, wherein the low-pass filtering for the active speech signal is different than the low-pass filtering for the inactive speech signal, and the high-pass filtering for the active speech signal is different than the high-pass filtering for the inactive speech signal.
14. The method of claim 10, wherein the transmitting includes a discontinuous transmission (DTX) scheme.
15. A speech encoder adapted to encode an input speech signal, the speech encoder comprising a receiver configured to receive the input speech signal; a voice activity detector configured to determine whether the input speech signal includes an active speech signal or an inactive speech signal; a low-pass filter for low-pass filtering the inactive speech signal to generate a narrowband inactive speech signal; a high-pass filter for high-pass filtering the inactive speech signal to generate a high-band inactive speech signal; a narrowband inactive speech encoder configured to encode the narrowband inactive speech signal to generate an encoded narrowband inactive speech, and the narrowband inactive speech encoder further configured to generate a first auxiliary signal based on the narrowband inactive speech signal; a wideband inactive speech encoder configured to encode the high-band inactive speech signal to generate an encoded wideband inactive speech based on the first auxiliary signal from the narrowband inactive speech encoder; a transmitter configured to transmit the encoded narrowband inactive speech and the encoded wideband inactive speech.
16. The speech encoder of claim 15, wherein the wideband inactive speech encoder further configured to generate a second auxiliary signal based on the high-band inactive speech signal, and wherein the narrowband inactive speech encoder is further configured to encode the narrowband inactive speech signal based on the second auxiliary signal from the wideband inactive speech encoder.
17. The speech encoder of claim 15, wherein the transmitter is configured to transmit according to a discontinuous transmission (DTX) scheme.
18. A speech encoder adapted to encode an input speech signal, the speech encoder comprising
28
PCT/US2008/001356 2007-02-14 2008-02-01 Embedded silence and background noise compression WO2008100385A2 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
AT08725056T ATE484053T1 (en) 2007-02-14 2008-02-01 EMBEDDED COMPRESSION FOR QUIET AND BACKGROUND NOISE
JP2009549588A JP5096498B2 (en) 2007-02-14 2008-02-01 Embedded silence and background noise compression
CN2008800047744A CN101606196B (en) 2007-02-14 2008-02-01 Embedded silence and background noise compression
EP08725056A EP2118891B1 (en) 2007-02-14 2008-02-01 Embedded silence and background noise compression
DE602008002902T DE602008002902D1 (en) 2007-02-14 2008-02-01 EMBEDDED COMPRESSION FOR CALM AND BACKGROUND RUSH

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US90119107P 2007-02-14 2007-02-14
US60/901,191 2007-02-14
US12/002,131 US8032359B2 (en) 2007-02-14 2007-12-14 Embedded silence and background noise compression
US12/002,131 2007-12-14

Publications (3)

Publication Number Publication Date
WO2008100385A2 WO2008100385A2 (en) 2008-08-21
WO2008100385A3 WO2008100385A3 (en) 2009-04-23
WO2008100385A4 true WO2008100385A4 (en) 2009-06-11

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2008/001356 WO2008100385A2 (en) 2007-02-14 2008-02-01 Embedded silence and background noise compression

Country Status (7)

Country Link
US (2) US8032359B2 (en)
EP (2) EP2118891B1 (en)
JP (1) JP5096498B2 (en)
CN (2) CN102592600B (en)
AT (2) ATE533148T1 (en)
DE (1) DE602008002902D1 (en)
WO (1) WO2008100385A2 (en)

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Also Published As

Publication number Publication date
EP2118891A2 (en) 2009-11-18
JP2010518453A (en) 2010-05-27
US8032359B2 (en) 2011-10-04
JP5096498B2 (en) 2012-12-12
CN101606196A (en) 2009-12-16
EP2224429A3 (en) 2010-09-22
EP2224429B1 (en) 2011-11-09
US8195450B2 (en) 2012-06-05
US20080195383A1 (en) 2008-08-14
WO2008100385A2 (en) 2008-08-21
CN102592600A (en) 2012-07-18
EP2224429A2 (en) 2010-09-01
CN102592600B (en) 2016-08-24
DE602008002902D1 (en) 2010-11-18
EP2118891B1 (en) 2010-10-06
ATE484053T1 (en) 2010-10-15
CN101606196B (en) 2012-04-04
ATE533148T1 (en) 2011-11-15
US20110320194A1 (en) 2011-12-29
WO2008100385A3 (en) 2009-04-23

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