WO2019034154A1 - Procédé et dispositif de réduction de bruit pour terminal mobile, et support de stockage informatique - Google Patents

Procédé et dispositif de réduction de bruit pour terminal mobile, et support de stockage informatique Download PDF

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Publication number
WO2019034154A1
WO2019034154A1 PCT/CN2018/101136 CN2018101136W WO2019034154A1 WO 2019034154 A1 WO2019034154 A1 WO 2019034154A1 CN 2018101136 W CN2018101136 W CN 2018101136W WO 2019034154 A1 WO2019034154 A1 WO 2019034154A1
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WO
WIPO (PCT)
Prior art keywords
noise reduction
mobile terminal
parameter
coordinate data
posture
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Application number
PCT/CN2018/101136
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English (en)
Chinese (zh)
Inventor
于冰
刘波
谢姣
孙家训
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西安中兴新软件有限责任公司
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Publication of WO2019034154A1 publication Critical patent/WO2019034154A1/fr

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic
    • 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
    • G10L21/00—Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
    • G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
    • G10L21/0208—Noise filtering
    • 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
    • G10L21/00—Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
    • G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
    • G10L21/0272—Voice signal separating
    • G10L21/028—Voice signal separating using properties of sound source
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/02—Constructional features of telephone sets
    • H04M1/19—Arrangements of transmitters, receivers, or complete sets to prevent eavesdropping, to attenuate local noise or to prevent undesired transmission; Mouthpieces or receivers specially adapted therefor

Definitions

  • the present disclosure relates to, but is not limited to, hand-held calling technology.
  • Handheld voice calls on mobile phones are the most widely used basic functions. In a noisy environment, making a hand-held call makes it difficult for the other party to hear the spoken content.
  • a dual MIC including a primary microphone (MIC) and a secondary MIC can be used to eliminate background noise to enhance the uplink voice call effect.
  • the mouth of the person is closer to the main MIC of the mobile phone and farther away from the auxiliary MIC. Therefore, the voice signal picked up by the main MIC is larger, and the signal picked up by the auxiliary MIC is smaller. The signal picked up by the main MIC subtracts the signal picked up by the auxiliary MIC to cancel out the background noise.
  • the same noise reduction parameter is used for different postures of the user's handheld mobile phone, so that in different postures, the voice volume is too small, or the noise reduction effect is deteriorated, so that the call volume and the noise reduction effect are both The aspect cannot be balanced.
  • An embodiment of the present disclosure provides a method for reducing noise of a mobile terminal, including: collecting current posture information of the mobile terminal when the mobile terminal enters a handheld call mode; and calling and moving from a pre-established noise reduction parameter calibration database a noise reduction parameter configuration file corresponding to the current posture information of the terminal; and performing audio correction and noise reduction processing on the dual microphone of the mobile terminal according to the called noise reduction parameter configuration file.
  • An embodiment of the present disclosure further provides a noise reduction device of a mobile terminal, including: an acquisition unit, when the mobile terminal enters a handheld call mode, the collection unit collects current posture information of the mobile terminal; and a noise reduction processing unit And setting a noise reduction parameter configuration file corresponding to the current posture information of the mobile terminal from a preset noise reduction parameter calibration database, and performing audio on the dual microphone of the mobile terminal according to the invoked noise reduction parameter configuration file. Correction and noise reduction processing.
  • Embodiments of the present disclosure also provide a computer storage medium having stored thereon one or more programs, the one or more programs being executed by one or more processors, the one or more processors executing A noise reduction method of a mobile terminal according to the present disclosure.
  • Figure 1 schematically shows the posture of a standard user-held mobile phone
  • Figure 2 is a schematic illustration of the posture of a non-standard user-held mobile phone
  • FIG. 3 is a flowchart of a noise reduction method of a mobile terminal according to an embodiment of the present disclosure
  • FIG. 4 is a structural block diagram of a noise reduction device of a mobile terminal according to an embodiment of the present disclosure
  • FIG. 5 illustrates a schematic diagram of generating attitude coordinate data in accordance with an embodiment of the present disclosure
  • FIG. 6 shows a diagram of frequency response curve data for a primary microphone and a secondary microphone, in accordance with an embodiment of the present disclosure
  • FIG. 7 shows a schematic diagram of a fit curve between a pose and a parameter correction variable in accordance with an embodiment of the present disclosure
  • FIG. 8 illustrates a flow chart of a noise reduction method of a mobile terminal according to an embodiment of the present disclosure.
  • the voice signal V MAIN picked up by the main MIC may include a call audio signal V CALL_MAIN and a background noise signal V NOISE_MAIN to be filtered out.
  • the voice signal V AUX picked up by the secondary MIC may include a call audio signal V CALL_AUX and a background noise signal V NOISE_AUX to be filtered out.
  • the calculation formula for finally obtaining the speech signal V VOICE by subtracting the speech signal V AUX picked up by the auxiliary MIC from the speech signal V MAIN picked up by the main MIC is as follows:
  • a noise reduction algorithm is needed to implement and optimize the noise reduction function of the dual MIC. In order to effectively eliminate the noise and at the same time ensure the volume of the normal call, it is necessary to obtain a V VOICE signal with a suitable gain.
  • Various noise reduction algorithms each define the gain range of V VOICE to ensure the volume of the call and effective noise reduction.
  • the gain range is defined as [A:B]dB, ie:
  • Fig. 1 schematically shows the posture of a standard user hand held mobile phone
  • Fig. 2 schematically shows the posture of a non-standard user hand held mobile phone.
  • V VOICE (V CALL_MAIN -V CALL_AUX )+(V NOISE_MAIN -V NOISE_AUX ) (2)
  • V VOICE V CALL_MAIN -V CALL_AUX (3)
  • V CALL_MAIN is large and V CALL_AUX is small, so it is easy to adjust V VOICE within the range of [A: B] dB.
  • V CALL_AUX in the language signal V AUX picked up by the auxiliary MIC does not substantially change, so that the V VOICE obtained by the above formula (3) also becomes small.
  • the V VOICE obtained by the above formula (3) does not fall within the range of [A: B] dB.
  • Table 1 shows the various indicator parameters for noise reduction using fixed noise reduction parameters 0 dB and 5 dB for different hand gestures. It will be appreciated that the V CALL_MAIN and V CALL_AUX values in Table 1 select typical values for the frequency response curve to roughly represent the average difference in gain of the two frequency response curves.
  • the gesture information of the mobile phone in different handheld postures can be collected and different noise reduction parameter profiles can be generated in advance for calling in a hand-held call, thereby solving the problem of improving the voice volume and achieving noise reduction in a non-standard posture. problem.
  • FIG. 3 is a flowchart of a noise reduction method of a mobile terminal according to an embodiment of the present disclosure.
  • the noise reduction method of the mobile terminal may include steps S101 to S103.
  • step S101 when the mobile terminal enters the handheld call mode, the current posture information of the mobile terminal is collected.
  • step S102 a noise reduction parameter configuration file corresponding to the current posture information of the mobile terminal is called from the pre-established noise reduction parameter calibration database.
  • step S103 audio correction and noise reduction processing are performed on the dual MIC of the mobile terminal according to the called noise reduction parameter profile.
  • the pre-generated noise reduction parameter calibration database stores at least a noise reduction parameter profile corresponding to the posture information of the mobile terminal, wherein the posture information includes posture coordinate data of the mobile terminal, and the drop corresponding to the posture information
  • the noise parameter profile includes a plurality of parameter correction variables for audio correction and noise reduction processing in the respective poses.
  • the noise reduction method of the mobile terminal may further include the step of establishing a noise reduction parameter calibration database in advance, the step may include: collecting various posture coordinate data of the mobile terminal; testing the mobile terminal under various posture coordinate data The main MIC and the auxiliary MIC audio data to generate frequency response curve data of the main MIC and the auxiliary MIC under different attitude coordinate data; in the generated frequency response curve data of the main MIC and the auxiliary MIC, select a plurality of typical Frequency points, and parameter correction variables are respectively set for the selected typical frequency points; and various posture coordinate data and corresponding plurality of parameter correction variables are fitted to generate a noise reduction parameter configuration file and stored.
  • step S102 may include: searching, in the noise reduction parameter calibration database, posture coordinate data having the smallest difference from the posture coordinate data in the current posture information of the mobile terminal; and according to the obtained posture coordinate data and corresponding multiple a fitting result of the parameter correction variable generates a parameter correction variable corresponding to the posture coordinate data in the current posture information of the mobile terminal; and obtaining a noise reduction parameter configuration file corresponding to the current posture information of the mobile terminal according to the generated parameter correction variable .
  • various attitude coordinate data of the mobile terminal may be acquired using an orientation sensor such as an acceleration transmission, a gyroscope, or the like.
  • FIG. 4 is a structural block diagram of a noise reduction device of a mobile terminal according to an embodiment of the present disclosure.
  • the device of the mobile terminal may include an acquisition unit 401 and a noise reduction processing unit 402.
  • the collecting unit 401 collects the current posture information of the mobile terminal.
  • the noise reduction processing unit 402 is configured to call a noise reduction parameter configuration file corresponding to the current posture information of the mobile terminal from the pre-established noise reduction parameter calibration database 403, and configure the file to the dual MIC of the mobile terminal according to the called noise reduction parameter configuration file. Perform audio correction and noise reduction processing.
  • the frequency response curves of the main MIC and the auxiliary MIC are corrected at each frequency point to realize the main MIC and the auxiliary MIC frequency response curve for the noise reduction calculation during the call.
  • the pre-generated noise reduction parameter calibration database 403 stores at least a noise reduction parameter profile corresponding to the posture information of the mobile terminal, wherein the posture information includes posture coordinate data of the mobile terminal, and corresponds to the posture information.
  • the noise reduction parameter profile includes a plurality of parameter correction variables for audio correction and noise reduction processing in the respective poses.
  • the noise reducer may further include a noise reduction parameter calibration database generation unit 404.
  • the noise reduction parameter calibration database generating unit 404 may include an audio data testing module 4041, an audio parameter correction module 4042, and a noise reduction parameter calibration module 4043.
  • the handset In an audio lab environment, the handset is fixed in various poses using a hand-held mode fixture, and the attitude coordinates data of the mobile terminal in various poses is acquired by the acquisition unit 401.
  • the audio data testing module 4041 tests the audio data of the primary MIC and the secondary MIC of the mobile terminal under various attitude coordinate data to generate frequency response curve data of the primary MIC and the secondary MIC under different attitude coordinate data.
  • FIG. 5 illustrates a schematic diagram of generating attitude coordinate data in accordance with an embodiment of the present disclosure.
  • various posture coordinate data of the mobile terminal can be acquired by an acceleration sensor, a gyroscope, or the like.
  • the audio parameter correction module 4042 is configured to select a plurality of typical frequency points in the frequency response curve data of the main MIC and the auxiliary MIC generated by the audio data test module 4041, and set a parameter correction variable ⁇ for the selected typical frequency points. That is, the main MIC gain and the gain of the secondary MIC are appropriately corrected.
  • FIG. 6 shows a diagram of frequency response curve data for a primary microphone and a secondary microphone, in accordance with an embodiment of the present disclosure.
  • the thick solid line indicates the frequency response curve of the main MIC (referred to as "frequency response curve")
  • the thin solid line indicates the frequency response curve before the auxiliary MIC correction
  • the thin dotted line indicates the modified frequency response curve of the auxiliary MIC. .
  • the noise reduction parameter calibration module 4043 is configured to fit the various posture coordinate data collected by the acquisition unit 401 and the corresponding plurality of parameter correction variables ⁇ to generate a noise reduction parameter configuration file and store the same.
  • the noise reduction processing unit 402 may be configured to: in the noise reduction parameter calibration database 403, look up posture coordinate data having the smallest difference from the posture coordinate data in the current posture information of the mobile terminal; The data and the corresponding fitting result of the plurality of parameter correction variables generate a parameter correction variable corresponding to the posture coordinate data in the current posture information of the mobile terminal; and obtain a parameter corresponding to the current posture information of the mobile terminal according to the generated parameter correction variable.
  • Noise reduction parameter configuration file in the noise reduction parameter calibration database 403, look up posture coordinate data having the smallest difference from the posture coordinate data in the current posture information of the mobile terminal.
  • the data and the corresponding fitting result of the plurality of parameter correction variables generate a parameter correction variable corresponding to the posture coordinate data in the current posture information of the mobile terminal; and obtain a parameter corresponding to the current posture information of the mobile terminal according to the generated parameter correction variable.
  • FIG. 7 shows a schematic diagram of a fit curve between a pose and a parameter correction variable in accordance with an embodiment of the present disclosure.
  • the noise reduction processing unit 402 can find the minimum difference between the attitude coordinate data of the posture 7 and the posture coordinate data of the posture 7 in the noise reduction parameter calibration database 403.
  • the attitude coordinate data finds that the posture coordinate data corresponding to the posture 3 and the posture 4 and the posture coordinate data corresponding to the posture 7 are closest to each other, and therefore, the posture 3 and the posture 4 and the parameter correction variable 3 and the parameter correction variable can be utilized.
  • the fitting result of 4 obtains the parameter correction variable ⁇ corresponding to the posture 7, for example, the parameter corresponding to the posture 7 can be obtained by the local linearization calculation of the parameter correction variable 3 and the parameter correction variable 4 corresponding to the posture 3 and the posture 4. Correct the variable ⁇ .
  • the parameter correction variable ⁇ corresponding to the posture 8 can be obtained by the fitting result of the posture 5 and the posture 6 with the parameter correction variable 5 and the parameter correction variable 6.
  • Table 2 shows various indicator parameters for noise reduction processing using different noise reduction parameters for different handheld gestures in accordance with an embodiment of the present disclosure.
  • FIG. 8 illustrates a flow chart of a noise reduction method of a mobile terminal according to an embodiment of the present disclosure.
  • the noise reduction method of the terminal may include steps S801 to S809.
  • step S801 the attitude coordinate data of the mobile phone is acquired by an azimuth sensor such as an acceleration sensor or a gyroscope.
  • step S802 the audio data of the primary MIC and the secondary MIC are tested under different handset gestures (ie, different attitude coordinate data) by the audio lab environment to generate frequency response curve data of the primary MIC and the secondary MIC.
  • step S803 a plurality of typical frequency points are selected in the frequency response curve data of the main MIC and the auxiliary MIC, and parameter correction variables are respectively set for each of the typical frequency points.
  • a noise reduction parameter profile is generated by fitting the attitude coordinate data and the frequency response curve data and stored in the noise reduction parameter calibration database.
  • step S805 it is judged whether or not the hand-held call mode is entered. If YES, the process proceeds to step S806, otherwise returns.
  • step S806 it is judged whether the hand posture is within a reasonable range. If YES, step S807 is continued, otherwise the mobile phone is considered to be out of the hand, and the flow is ended.
  • the "reasonable range" referred to in step S806 includes standard hand held gestures and various non-standard hand held gestures. When it is detected that the reasonable range is exceeded, it indicates that the mobile phone has been removed from the handheld, for example, in a hands-free conversation state.
  • step S807 the current posture coordinate data of the mobile phone is acquired.
  • step S808 the corresponding noise reduction parameter configuration file is called according to the collected posture coordinate data, and the frequency response curve data of the main MIC and the auxiliary MIC are corrected at each frequency point.
  • step S809 the noise reduction algorithm is performed using the frequency response curve data of the optimized main MIC and the auxiliary MIC to achieve noise reduction.
  • Embodiments of the present disclosure also provide a computer storage medium having stored thereon one or more programs, the one or more programs being executable by one or more processors such that the one or more processors are implemented
  • a noise reduction method of a mobile terminal according to the above embodiments of the present disclosure.
  • the gesture information of the mobile phone in different handheld gestures can be collected and different noise reduction parameter profiles can be generated in advance for calling in the hand-held call, thereby achieving the voice volume in a non-standard posture. Noise reduction.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computational Linguistics (AREA)
  • Quality & Reliability (AREA)
  • Health & Medical Sciences (AREA)
  • Audiology, Speech & Language Pathology (AREA)
  • Human Computer Interaction (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
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Abstract

La présente invention concerne un procédé et un dispositif de réduction de bruit pour terminal mobile, et un support de stockage informatique. Le procédé comprend les étapes suivantes : lorsqu'un terminal mobile entre dans un mode de haut-parleur, acquérir des informations d'orientation actuelle du terminal mobile; invoquer un document de configuration de paramètre de réduction de bruit correspondant aux informations d'orientation actuelle du terminal mobile à partir d'une base de données d'étalonnage de paramètre de réduction de bruit pré-construite; et effectuer une modification audio et un traitement de réduction de bruit sur deux microphones du terminal mobile selon le document de configuration de paramètre de réduction de bruit invoqué.
PCT/CN2018/101136 2017-08-17 2018-08-17 Procédé et dispositif de réduction de bruit pour terminal mobile, et support de stockage informatique WO2019034154A1 (fr)

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CN201710709083.5A CN109413253A (zh) 2017-08-17 2017-08-17 一种实现移动终端的消噪方法及装置

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CN110191220B (zh) * 2019-05-31 2021-09-10 维沃移动通信有限公司 一种语音处理方法及终端设备
CN112261201B (zh) * 2020-10-20 2022-08-05 Oppo广东移动通信有限公司 通话方法、装置、移动终端及存储介质

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CN104363543B (zh) * 2014-11-10 2017-10-20 广东欧珀移动通信有限公司 麦克风频响曲线的调整方法及装置
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CN102739867A (zh) * 2012-06-19 2012-10-17 青岛海信移动通信技术股份有限公司 一种双mic降噪方法及移动终端
CN102801861A (zh) * 2012-08-07 2012-11-28 歌尔声学股份有限公司 一种应用于手机的语音增强方法和装置
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