EP0869476A1 - Vorrichtung zur Erzeugung von Hintergrundrauschen und Elemente dieser Vorrichtung verwendendes Sprachcodec - Google Patents

Vorrichtung zur Erzeugung von Hintergrundrauschen und Elemente dieser Vorrichtung verwendendes Sprachcodec Download PDF

Info

Publication number
EP0869476A1
EP0869476A1 EP98200761A EP98200761A EP0869476A1 EP 0869476 A1 EP0869476 A1 EP 0869476A1 EP 98200761 A EP98200761 A EP 98200761A EP 98200761 A EP98200761 A EP 98200761A EP 0869476 A1 EP0869476 A1 EP 0869476A1
Authority
EP
European Patent Office
Prior art keywords
frame
gain
circuit
available
noise
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
EP98200761A
Other languages
English (en)
French (fr)
Other versions
EP0869476B1 (de
Inventor
Cyrille Morel
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.)
Koninklijke Philips NV
Original Assignee
Koninklijke Philips Electronics NV
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 Koninklijke Philips Electronics NV filed Critical Koninklijke Philips Electronics NV
Publication of EP0869476A1 publication Critical patent/EP0869476A1/de
Application granted granted Critical
Publication of EP0869476B1 publication Critical patent/EP0869476B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10L—SPEECH ANALYSIS TECHNIQUES OR SPEECH SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING TECHNIQUES; 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

Definitions

  • the present invention relates to a device for comfort noise generation, as well as an encoder and a speech decoder including elements of such a device.
  • a voice activity detector which makes it possible to locate, in input signals where voice signals are mixed with noise and moments of silence, periods when speech signals are here.
  • the following speech coder transmits regularly (all frames) a stream of digital data that will allow a interlocutor say so much to reconstitute these speech signals.
  • we no longer detects speech signals we no longer send coded frames on the network, in order to save speed on it.
  • a first object of the invention is to propose a comfort noise generating device remedying this disadvantage and which for this purpose is characterized in that it includes, in coding, in parallel, a determination circuit of the energy of the current frame - the input signals being available as successive length frames predetermined - and an envelope determination circuit of this frame by so-called LPC analysis, and, on decoding, in series, a circuit for generating a Gaussian noise, a subset two gain definition channels in parallel, and one adder of the outputs of said channels, the noise frame of comfort restored in the absence of speech signals in the current input frame being available on the output of said adder.
  • This device allows to return to the interlocutor remote better message quality. Indeed, in transmitting during the periods of silence a few frames which contain the essential characteristics of ambient noise, we remove this unpleasant impression of line break in total silence.
  • the coding of these few noise frames is very inexpensive in debit, since there is only to send the frequency and energy characteristics of the signal noise, which are sufficient to restore, to the interlocutor, a substantially equivalent noise.
  • comfort noise generation devices are already provided in the speech coders described for example in the project recommendation issued recently by the International Union of Telecommunications (ITU), "Draft Recommendation G.723 - Dual rate speech coder for multimedia telecommunication transmitting at 5.3 and 6.3 kbits / s ", ITU, Study Group 15, 1995, 10th” LBC Meeting ", Newton, Ma., USA, aimed at defining a standard for a speech coder.
  • comfort noise generation is very strongly nested in the speech encoder.
  • the method used does not depend on the coder. We do not no longer uses waveform dictionaries, which were traditionally present in speech coders.
  • the addition to the filtered noise of a Gaussian noise is particularly interesting when ambient noise is very weak.
  • Another object of the invention is to propose a speech coder and decoder including elements of a comfort noise generation device as described above.
  • the input signals are available in the form of successive frames TR n-1 , TR n , ... etc ... of predetermined duration.
  • the device described comprises first of all, as indicated in the figure, a circuit 11 for determining the energy of the current frame, also called gain analysis, as well as a circuit 12 for determining the envelope of this frame (from the frequency point of view) by means of an analysis called LPC (in English: l inear p redictive c oding) which makes it possible to estimate coefficients of linear prediction.
  • LPC in English: l inear p redictive c oding
  • the device includes first a circuit 21 for generating a Gaussian noise (or, at least, noise constituting an approximation of a Gaussian noise).
  • This circuit is not a dictionary of shapes wave and therefore does not require memory.
  • the calculation allowing this generation is a sum, made in time real, of pseudo-random numbers (we get a signal Gaussian if the number of iterations is large enough, less than ten generally sufficient).
  • This noise is sent in parallel on two gain definition channels 30 and 40 including the first includes in series a gain circuit 31 (this gain is determined by the energy - which has been transmitted - of the frame current), a filter 32 (whose LPC coefficients - also transmitted- have been estimated as indicated above) and a multiplier 33.
  • the output of this multiplier 33 and that of a similar multiplier 43 constituting the other path 40 constitute the inputs of a adder 25 at the output of which the noise frame is present TBC comfort level reconstituted in the absence of speech signals.
  • the present invention is not limited to this exemplary embodiment, from which variants may be provided.
  • decoding we can take into account that we reduced the flow by not not transmitting each time a coded frame: to decrease abrupt transitions, it is then possible to make a interpolation with the previous frames, with regard to energy and filter coefficients. Can also improve quality by also providing for coding a interpolation of the energy of the past frames.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computational Linguistics (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Audiology, Speech & Language Pathology (AREA)
  • Human Computer Interaction (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Compression, Expansion, Code Conversion, And Decoders (AREA)
  • Transmission Systems Not Characterized By The Medium Used For Transmission (AREA)
EP98200761A 1997-03-25 1998-03-10 Vorrichtung zur Erzeugung von Hintergrundrauschen Expired - Lifetime EP0869476B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9703617A FR2761512A1 (fr) 1997-03-25 1997-03-25 Dispositif de generation de bruit de confort et codeur de parole incluant un tel dispositif
FR9703617 1997-03-25

Publications (2)

Publication Number Publication Date
EP0869476A1 true EP0869476A1 (de) 1998-10-07
EP0869476B1 EP0869476B1 (de) 2004-11-17

Family

ID=9505153

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98200761A Expired - Lifetime EP0869476B1 (de) 1997-03-25 1998-03-10 Vorrichtung zur Erzeugung von Hintergrundrauschen

Country Status (6)

Country Link
US (1) US6108623A (de)
EP (1) EP0869476B1 (de)
JP (1) JPH10340097A (de)
CN (1) CN1132327C (de)
DE (1) DE69827545T2 (de)
FR (1) FR2761512A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2356538A (en) * 1999-11-22 2001-05-23 Mitel Corp Comfort noise generation for open discontinuous transmission systems

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6240383B1 (en) * 1997-07-25 2001-05-29 Nec Corporation Celp speech coding and decoding system for creating comfort noise dependent on the spectral envelope of the speech signal
US6621834B1 (en) * 1999-11-05 2003-09-16 Raindance Communications, Inc. System and method for voice transmission over network protocols
US20030120484A1 (en) * 2001-06-12 2003-06-26 David Wong Method and system for generating colored comfort noise in the absence of silence insertion description packets
US20030093270A1 (en) * 2001-11-13 2003-05-15 Domer Steven M. Comfort noise including recorded noise
US7243065B2 (en) * 2003-04-08 2007-07-10 Freescale Semiconductor, Inc Low-complexity comfort noise generator
US20120029926A1 (en) 2010-07-30 2012-02-02 Qualcomm Incorporated Systems, methods, apparatus, and computer-readable media for dependent-mode coding of audio signals
US9208792B2 (en) * 2010-08-17 2015-12-08 Qualcomm Incorporated Systems, methods, apparatus, and computer-readable media for noise injection
US8589153B2 (en) 2011-06-28 2013-11-19 Microsoft Corporation Adaptive conference comfort noise
ES2881672T3 (es) * 2012-08-29 2021-11-30 Nippon Telegraph & Telephone Método de descodificación, aparato de descodificación, programa, y soporte de registro para ello
CN104978970B (zh) 2014-04-08 2019-02-12 华为技术有限公司 一种噪声信号的处理和生成方法、编解码器和编解码系统
GB2532041B (en) 2014-11-06 2019-05-29 Imagination Tech Ltd Comfort noise generation
CN109841222B (zh) * 2017-11-29 2022-07-01 腾讯科技（深圳）有限公司 音频通信方法、通信设备及存储介质

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63124636A (ja) * 1986-11-14 1988-05-28 Kokusai Denshin Denwa Co Ltd <Kdd> 音声伝送システムの疑似信号挿入方式
US5537509A (en) * 1990-12-06 1996-07-16 Hughes Electronics Comfort noise generation for digital communication systems

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2021514C (en) * 1989-09-01 1998-12-15 Yair Shoham Constrained-stochastic-excitation coding
US5327457A (en) * 1991-09-13 1994-07-05 Motorola, Inc. Operation indicative background noise in a digital receiver
US5828997A (en) * 1995-06-07 1998-10-27 Sensimetrics Corporation Content analyzer mixing inverse-direction-probability-weighted noise to input signal
US5689615A (en) * 1996-01-22 1997-11-18 Rockwell International Corporation Usage of voice activity detection for efficient coding of speech
US5864799A (en) * 1996-08-08 1999-01-26 Motorola Inc. Apparatus and method for generating noise in a digital receiver

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63124636A (ja) * 1986-11-14 1988-05-28 Kokusai Denshin Denwa Co Ltd <Kdd> 音声伝送システムの疑似信号挿入方式
US5537509A (en) * 1990-12-06 1996-07-16 Hughes Electronics Comfort noise generation for digital communication systems

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 012, no. 375 (E - 666) 7 October 1988 (1988-10-07) *
SOUTHCOTT C B ET AL: "VOICE CONTROL OF THE PAN-EUROPEAN DIGITAL MOBILE RADIO SYSTEM", COMMUNICATIONS TECHNOLOGY FOR THE 1990'S AND BEYOND, DALLAS, NOV. 27 - 30, 1989, vol. 2 OF 3, 27 November 1989 (1989-11-27), INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS, pages 1070 - 1074, XP000091191 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2356538A (en) * 1999-11-22 2001-05-23 Mitel Corp Comfort noise generation for open discontinuous transmission systems
US6711537B1 (en) 1999-11-22 2004-03-23 Zarlink Semiconductor Inc. Comfort noise generation for open discontinuous transmission systems

Also Published As

Publication number Publication date
CN1132327C (zh) 2003-12-24
FR2761512A1 (fr) 1998-10-02
JPH10340097A (ja) 1998-12-22
DE69827545D1 (de) 2004-12-23
US6108623A (en) 2000-08-22
DE69827545T2 (de) 2005-12-15
CN1194507A (zh) 1998-09-30
EP0869476B1 (de) 2004-11-17

Similar Documents

Publication Publication Date Title
EP0768770B1 (de) Verfahren und Vorrichtung zur Erzeugung von Hintergrundrauschen in einem digitalen Übertragungssystem
EP0139803B1 (de) Verfahren zur Wiederherstellung von verlorengegangenen Informationen in einem digitalen Sprachübertragungssystem und Übertragungssystem welches dieses Verfahren anwendet
EP0782128B1 (de) Verfahren zur Analyse eines Audiofrequenzsignals durch lineare Prädiktion, und Anwendung auf ein Verfahren zur Kodierung und Dekodierung eines Audiofrequenzsignals
EP0869476A1 (de) Vorrichtung zur Erzeugung von Hintergrundrauschen und Elemente dieser Vorrichtung verwendendes Sprachcodec
EP0710947B1 (de) Verfahren und Apparat zur Geräuschunterdrückung in einem Sprachsignal und korrespondierendes System mit Echounterdrückung
EP0002998B1 (de) Verfahren und Vorrichtung zur Sprachdatenkompression
EP0608174A1 (de) System zur prädiktiven Kodierung/Dekodierung eines digitalen Sprachsignals mittels einer adaptiven Transformation mit eingebetteten Kodes
FR2520539A1 (fr) Procede et systeme de traitement des silences dans un signal de parole
EP1401183B1 (de) Verfahren und Vorrichtung zur Echokompensation
EP0130263B1 (de) Startverfahren für einen Echokompensationsfilter und dieses Verfahren anwendendes Nachrichtenübertragungssystem
EP0127718A1 (de) Verfahren zur Aktivitätsdetektion in einem Sprachübertragungssystem
EP1730729A1 (de) Verbessertes sprachsignalumsetzungsverfahren und -system
EP1356455B1 (de) Verfahren und vorrichtung zur verarbeitung von mehreren audiobitströmen
Wang et al. A robust audio-visual speech enhancement model
EP0428445B1 (de) Verfahren und Einrichtung zur Codierung von Prädiktionsfiltern in Vocodern mit sehr niedriger Datenrate
EP1875465A1 (de) Verfahren zur anpassung für interoperabilität zwischen kurzzeit-korrelationsmodellen digitaler signale
EP1039736B1 (de) Verfahren und Vorrichtung zur adaptiven Identifikation und entsprechender adaptiver Echokompensator
FR2739481A1 (fr) Appareil et procede d&#39;elimination du bruit
EP0030194B1 (de) Prediktorstufe für ein System zur Kompression des Datenflusses
FR2793589A1 (fr) Dispositif pour traiter l&#39;information de phase d&#39;un signal acoustique et procede correspondant
EP2691953A1 (de) Verarbeitung eines codierten audiosignals im kodierten bereich durch micda-kodierung
EP0444993B1 (de) Quantisierungsvorrichtung mit variablem digitalem Kodierungsfluss
EP1217613A1 (de) Wiederherstellung von schlechten oder fehlenden Rahmen in zellularer Telefonie
FR2802375A1 (fr) Dispositif de traitement de l&#39;echo dans un systeme de communication au niveau d&#39;un terminal
EP0368417A1 (de) Anordnung mit einer verbesserten Gleichstrompegelauswertungsvorrichtung

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

17P Request for examination filed

Effective date: 19990407

AKX Designation fees paid

Free format text: DE FR GB

17Q First examination report despatched

Effective date: 20020730

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

RTI1 Title (correction)

Free format text: COMFORT NOISE GENERATION DEVICE

RIC1 Information provided on ipc code assigned before grant

Ipc: 7G 10L 19/00 A

RTI1 Title (correction)

Free format text: COMFORT NOISE GENERATION DEVICE

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REF Corresponds to:

Ref document number: 69827545

Country of ref document: DE

Date of ref document: 20041223

Kind code of ref document: P

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20050221

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20050818

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20070327

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20070329

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20080515

Year of fee payment: 11

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20080310

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20081125

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080331

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080310

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20091001