WO2016013286A1 - Dispositif de calcul de différence de phase, dispositif de détection de direction de source sonore, et procédé de calcul de différence de phase - Google Patents

Dispositif de calcul de différence de phase, dispositif de détection de direction de source sonore, et procédé de calcul de différence de phase Download PDF

Info

Publication number
WO2016013286A1
WO2016013286A1 PCT/JP2015/064814 JP2015064814W WO2016013286A1 WO 2016013286 A1 WO2016013286 A1 WO 2016013286A1 JP 2015064814 W JP2015064814 W JP 2015064814W WO 2016013286 A1 WO2016013286 A1 WO 2016013286A1
Authority
WO
WIPO (PCT)
Prior art keywords
phase difference
microphone
audio signal
sound source
phase
Prior art date
Application number
PCT/JP2015/064814
Other languages
English (en)
Japanese (ja)
Inventor
中村　圭介
Original Assignee
シャープ株式会社
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 シャープ株式会社 filed Critical シャープ株式会社
Publication of WO2016013286A1 publication Critical patent/WO2016013286A1/fr

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
    • G01S3/80—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using ultrasonic, sonic or infrasonic waves
    • G01S3/802—Systems for determining direction or deviation from predetermined direction
    • G01S3/808—Systems for determining direction or deviation from predetermined direction using transducers spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
    • H04R1/40—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones

Definitions

  • the present invention relates to a phase difference calculation device that calculates a phase difference between audio signals obtained from a plurality of microphones, a sound source direction detection device including the phase difference calculation device, and a phase difference calculation method.
  • a technique for detecting the direction or position of a sound source by measuring a temporal shift (phase difference) of an audio signal obtained from each microphone using a plurality of microphones is known.
  • a technique for determining the phase difference of an audio signal obtained from each of a plurality of microphones there is a technique for obtaining a phase difference spectrum in an acoustic signal as disclosed in Patent Document 1 and Patent Document 2, for example.
  • Patent Document 1 a phase difference spectrum in two acoustic signals is obtained, and all or part of the obtained phase difference spectrum is approximated by a linear function relating to a frequency passing through the origin, and the direction of the sound source is determined from the slope of the linear function.
  • a method for calculating is disclosed.
  • Patent Document 2 obtains a phase difference spectrum between two acoustic signals, obtains a power spectrum of at least one of the two acoustic signals, and generates a sound source for each sound source based on the obtained phase difference spectrum and the power spectrum.
  • a method for determining a direction is disclosed.
  • the frequency component of human voice greatly fluctuates depending on the pronunciation of words. Therefore, when a human voice is a sound source, it is difficult to accurately measure the deviation of each audio signal obtained from a plurality of microphones. For example, the sound of “shi” includes many relatively high-frequency sounds, and “o” includes many low-frequency sounds.
  • the sound input to each microphone is not necessarily a sound from a single sound source like the utterance from a single person, but also includes ambient noise and reflected sound from nearby walls.
  • the same waveform signal shifted on the axis is not input to each microphone in the same manner. Therefore, it is difficult to accurately measure the deviation of each signal when the surrounding noise is large or there is a hard wall that easily reflects sound in the vicinity.
  • an object of the present invention is to provide a phase difference calculation device and a phase difference calculation device that can more accurately calculate a phase difference between audio signals output from different microphones.
  • An object of the present invention is to provide a sound source direction detecting device including a device and a phase difference calculating method.
  • a phase difference calculation device includes a plurality of microphones that are arranged at different positions and that convert external sound into an audio signal and output the sound, and the plurality of microphones.
  • the phase-shifted audio signal in which the relative phase shift amount between the audio signal output from one of the microphones and the audio signal output from the other microphone is changed stepwise
  • a phase-shifted sound signal creating unit that creates each amount
  • an integrated value calculating unit that calculates an integrated value of the difference between output values within a certain range of the two sound signals in the phase-shifted sound signal corresponding to each phase-shifted amount
  • the phase difference between the audio signal output from the one microphone and the audio signal output from the other microphone based on the integrated value. It comprises a phase difference calculating unit for output, a.
  • a sound source direction detection method includes a step of converting external sound into an audio signal using a plurality of microphones arranged at different positions and outputting the sound signal; The phase-shifted sound in which the relative phase shift amount between the sound signal output from one of the plurality of microphones and the sound signal output from the other microphone is changed stepwise.
  • the phase difference between audio signals output from different microphones can be calculated more accurately.
  • FIG. 5 is a diagram for explaining a method of creating a deviation value graph from two audio data in an embodiment of the present invention.
  • FIG. 5 is a diagram for explaining a method of creating a deviation value graph from two audio data in an embodiment of the present invention. It is a figure which shows the example of audio
  • FIG. 5 is a shift value graph when the audio signal obtained from the first microphone in FIG. 4 is phase-shifted in the positive direction toward the audio signal obtained from the second microphone.
  • FIG. 6 is a diagram for explaining a method of specifying a sound source direction from a phase difference between two audio signals in an embodiment of the present invention. It is a figure which shows the example of audio
  • FIG. 1 is a block diagram showing a sound source direction detection device 1 according to this embodiment.
  • the sound source direction detection device 1 is a device that detects the direction of a sound source using a plurality of microphones.
  • the sound source direction detection device 1 can be mounted on, for example, a robot that has a conversation with a human. By detecting the direction of the person who is speaking by the sound source direction detection device 1, the face or line of sight of the robot can be directed toward the speaker.
  • the sound source direction detection device 1 can be mounted on the microphone unit of the telephone conference system.
  • the sound source direction detection device 1 can identify the person by detecting the direction of the person who is speaking among the participants in the conference.
  • the sound source direction detection device 1 can also be installed in a security monitoring system. Even an intruder who is hidden behind the object and is not reflected in the camera of the security monitoring system can detect the approximate position of the intruder if the sound source direction detection device 1 can detect sound.
  • the sound source direction detecting device 1 includes a first microphone 2a, a second microphone 2b, a first microphone signal input unit 3a, a second microphone signal input unit 3b, a first microphone signal storage unit 4a, and a second microphone.
  • a microphone signal storage unit 4b, an audio signal evaluation unit 5, a sound source direction specifying unit 6 (specifying unit), and an angle table 7 are provided.
  • the first microphone 2a, the second microphone 2b, the first microphone signal input unit 3a, the second microphone signal input unit 3b, the first microphone signal storage unit 4a, the second microphone signal storage unit 4b, and the audio signal evaluation unit 5 However, it functions as the phase difference calculation apparatus 10 according to the present invention.
  • the first microphone 2a and the second microphone 2b are microphones that convert external sounds into audio signals.
  • the first microphone 2a and the second microphone 2b are arranged at different positions.
  • the first microphone signal input unit 3a creates sound data obtained by digitizing the sound signal converted by the first microphone 2a.
  • the second microphone signal input unit 3b creates audio data in which the audio signal converted by the second microphone 2b is digitized.
  • the audio data is data indicating the relationship between the output value of the audio signal and time (change in the output value of the audio signal over time).
  • the first microphone signal storage unit 4a stores voice data created by the first microphone signal input unit 3a
  • the second microphone signal storage unit 4b stores voice data created by the second microphone signal input unit 3b. is doing. Both the first microphone signal storage unit 4a and the second microphone signal storage unit 4b always store audio data for an arbitrary fixed time.
  • the audio signal evaluation unit 5 refers to the audio data stored in the first microphone signal storage unit 4a and the second microphone signal storage unit 4b, and measures the temporal shift of the audio signal represented by each audio data. Thus, the phase difference between the two audio signals is obtained.
  • a block diagram of the audio signal evaluation unit is shown in FIG. As shown in FIG. 2, the audio signal evaluation unit 5 includes a phase shift audio signal creation unit 51, a deviation value calculation unit 52 (integrated value calculation unit), a deviation value graph creation unit 53, a determination unit 54, and a phase difference calculation unit. 55. Details of these members and a method of calculating a phase difference by these members will be described later.
  • the sound source direction specifying unit 6 specifies the sound source direction based on the phase difference calculated by the audio signal evaluating unit 5. Specifically, the angle table 7 stores the angle direction corresponding to each phase difference, and when the phase difference is received from the sound source direction specifying unit 6, the angle of the sound source direction corresponding to the phase difference is specified. Send to part 6.
  • the angle of the sound source direction is an angle between the sound source direction and a reference direction.
  • the sound source direction specifying unit 6 specifies the angle direction of the sound source from the angle obtained using the angle table 7. Then, the sound source direction specifying unit 6 outputs the specified angular direction to the outside as a detection result of the sound source direction.
  • FIG. 3 and 4 are diagrams for explaining a method of creating a deviation value graph from two audio data.
  • audio data indicated by a solid line represents an audio signal obtained from the first microphone 2a
  • audio data indicated by a dotted line represents an audio signal obtained from the second microphone 2b.
  • the phase-shifted sound signal creating unit 51 of the sound signal evaluating unit 5 creates a phase-shifted sound signal in which the relative phase shift amount between two sound signals is changed stepwise for each phase shift amount.
  • the deviation value calculation unit 52 obtains an integrated value of the difference between the output values within a certain range of the two audio signals in the phase-shifted audio signal corresponding to each phase shift amount.
  • the difference between the output values is the absolute value of the difference between the output values of the two audio signals at a specific point (time).
  • These integrated values are the two audio signals within a certain range (in FIG. 2).
  • (A) in (A) is a gray area).
  • the integrated value of the difference between the output values within a certain range in the two audio signals is referred to as a “deviation value”. It is considered that the larger the deviation value, the larger the phase difference between the two audio signals, and the smaller the deviation value, the smaller the phase difference between the two audio signals.
  • the deviation value graph creating unit 53 creates a deviation value graph showing the change of the deviation value over time when the relative phase shift amount between the two audio signals is changed in stages.
  • FIG. 3B shows a state when the audio signal (solid line) obtained from the first microphone 2a in FIG. 3A is phase-shifted by +1 in the right direction (plus direction) of the drawing. Further, from this state, the state when the audio signal obtained from the first microphone 2a is phase-shifted by +1 in the right direction of the drawing is (C) in FIG. 3, and the state when the phase is further shifted by +1 is shown. It is (D) in FIG. By plotting the deviation value in each state, the deviation value graph shown in FIG. 2 is obtained.
  • the present invention is not necessarily limited thereto.
  • the audio signal obtained from the second microphone 2b may be phase-shifted with reference to the audio signal obtained from the first microphone 2a.
  • the deviation value graph when the audio signal obtained from the second microphone 2b in FIG. 3A is phase-shifted in the left direction (minus direction) in the drawing is the deviation value graph shown in FIG. .
  • the shift value graph when the audio signal obtained from the second microphone 2b of (A) in FIG. 4 is phase-shifted in the right direction (plus direction) in the drawing is the shift value graph shown in FIG.
  • the determination unit 54 determines whether or not the audio signals obtained from the first microphone 2a and the second microphone 2b are appropriate for calculating the phase difference based on the deviation value graph created by the deviation value graph creation unit 53. .
  • the phase difference calculation unit 55 includes the deviation value graph creation unit 53. Based on the generated deviation value graph, the phase difference between the audio signals obtained from the first microphone 2a and the second microphone 2b is calculated. A determination method by the determination unit 54 will be described later, and a phase difference calculation method by the phase difference calculation unit 55 will be described below.
  • FIG. 5 shows an example of sound data suitable for calculating the phase difference. Then, the deviation value graph when the audio signal evaluation unit 5 phase-shifts the audio signal obtained from the first microphone 2a in FIG. 5 in the positive direction toward the audio signal obtained from the second microphone 2b. Is shown in FIG.
  • the point where the deviation value is minimum is one point or two consecutive points.
  • the deviation value is minimized when the two audio signals substantially match. Therefore, the phase shift amount when the deviation value between the two audio signals becomes the minimum is the temporal deviation (phase difference) between the two audio signals.
  • the phase difference between the two audio signals is +9.
  • the integrated value (the difference between the output values of the two within a certain range when the relative phase shift amount between the audio signals output from the first microphone 2a and the second microphone 2b is changed stepwise.
  • the phase difference between the audio signals output from the first microphone 2a and the second microphone 2b can be calculated based on the deviation value. Therefore, the phase difference calculation unit 55 calculates the phase difference between the audio signals output from the first microphone 2a and the second microphone 2b based on the deviation value for each phase shift amount.
  • FIG. 7 is a diagram for explaining a method of specifying the sound source direction from the phase difference between two audio signals.
  • the direction from the second microphone 2b to the first microphone 2a is a 0 degree direction
  • the direction from the first microphone 2a to the second microphone 2b is a 180 degree direction.
  • the phase difference here refers to the phase shift amount of the audio signal obtained from the first microphone 2a with reference to the audio signal obtained from the second microphone 2b.
  • the locus of a point where the difference in distance from each of the two points is a constant amount is a hyperbolic function with the two points as the focal point. If the point is sufficiently far away from the distance between the two focal points, the point is located on the asymptote of the hyperbolic function, and the slope of the asymptote can be regarded as the direction in which the point is located. it can. That is, the sound source is located on the asymptote of the hyperbolic function having the respective positions of the first microphone 2a and the second microphone 2b as the focal points, and the direction in which the sound source is located can be regarded as the slope of the asymptote.
  • the angle of the sound source direction is arccos (9/14) ⁇ 50 degrees. Said angle is angle (theta) between 0 degree directions. That is, the sound source direction is a 50 degree direction.
  • the angle table 7 stores the angle of the sound source direction corresponding to each phase difference.
  • the sound source direction specifying unit 6 sends the phase difference calculated by the audio signal evaluation unit 5 to the angle table 7, the sound source direction specifying unit 6 receives the angle of the sound source direction corresponding to the phase difference from the angle table 7.
  • the sound source direction specifying unit 6 specifies the angle direction of the sound source from the angle obtained using the angle table 7 and outputs the specified angle direction to the outside as a detection result of the sound source direction.
  • the angle direction specified from the phase difference calculated by the audio signal evaluation unit 5 can be the left and right directions with respect to the straight line connecting the first microphone 2a and the second microphone 2b. Therefore, in the angle direction specified from one phase difference, it cannot be specified whether the sound source direction is the left and right directions with respect to the straight line connecting the first microphone 2a and the second microphone 2b. Therefore, the sound source direction detection device 1 according to the present embodiment is preferably used when detecting a sound source located on one side with respect to a straight line connecting the first microphone 2a and the second microphone 2b, such as when installed near a wall. .
  • FIG. 1 An example of audio data when there is a lot of noise around is shown in FIG. In this figure, in addition to the main voice showing a large waveform, another voice showing a small waveform is emitted from a different direction.
  • the audio signal evaluation unit 5 creates a deviation value graph by the same method as described above.
  • the created deviation value graph is as shown in FIG.
  • the point where the deviation value is minimum is one point or two consecutive points
  • the value of the minimum value is higher than that of the deviation value graph shown in FIG. This means that the degree of coincidence between the two audio signals is low.
  • the phase difference is calculated using such a deviation value graph, it is difficult to calculate an accurate phase difference, and it is easy to erroneously detect the sound source direction. For this reason, such a deviation value graph is inappropriate for calculating the phase difference and not suitable for detecting the direction of the sound source.
  • the determination unit 54 of the audio signal evaluation unit 5 sets a predetermined threshold value and a deviation value graph having a minimum value equal to or greater than the threshold value is obtained, the obtained audio data is not suitable for calculating the phase difference. Judge that it is appropriate. And the phase difference calculation part 55 does not calculate a phase difference using the said audio
  • the predetermined threshold is, for example, the minimum value of the deviation value graph obtained from appropriate audio data (the deviation value graph shown in FIG. 6) and the deviation value graph obtained from inappropriate audio data (the deviation shown in FIG. 9). It can be a value between the minimum value of the value graph).
  • FIG. 10 shows an example of high-frequency audio data exceeding a predetermined frequency. This figure shows a state in which sound having a dense waveform is emitted.
  • the audio signal evaluation unit 5 creates a deviation value graph by the same method as described above.
  • the created deviation value graph is as shown in FIG.
  • the phase difference is calculated using such a deviation value graph, it is difficult to calculate an accurate phase difference, and it is easy to erroneously detect the sound source direction. For this reason, such a deviation value graph is inappropriate for calculating the phase difference and not suitable for detecting the direction of the sound source.
  • the determination unit 54 of the audio signal evaluation unit 5 determines that the obtained audio data is inappropriate for calculating the phase difference when the deviation value graph has two or more minimum points. .
  • the phase difference calculation part 55 does not calculate a phase difference using the said audio
  • the number of minimum points in the deviation value graph can be easily obtained by counting the number of times the slope of the graph changes from ⁇ (negative value) to + (positive value).
  • the phase difference calculation unit 55 calculates the phase difference using only audio data appropriate for the phase difference calculation. Can do. For this reason, the sound source direction detection device 1 can calculate the phase difference more accurately.
  • the sound source direction specifying unit 6 can detect the sound source direction based on the phase difference calculated using only sound data appropriate for the calculation of the phase difference. For this reason, the sound source direction detection device 1 can detect the sound source direction more accurately.
  • the frequency component of human voice greatly fluctuates due to the pronunciation of words.
  • the sound signal may be intermittently generated due to mixing of other noise from the surroundings.
  • the sound source direction detecting device requires many processing members. It becomes.
  • the sound source direction detection apparatus 1 according to the present embodiment does not detect the sound source direction using the audio data as shown in FIGS. 9 and 11, the processing until the sound source direction is specified can be reduced. The processing members required for the sound source direction detection device 1 can be suppressed.
  • the determination unit 54 determines whether the audio data is appropriate for calculating the phase difference using the deviation value graph, and the phase difference calculation unit 55 uses the deviation value graph to determine whether the audio data is appropriate.
  • the phase difference between signals is calculated.
  • the sound source direction detection device 1 can determine whether or not the sound data is appropriate for calculating the phase difference and calculate the phase difference between the sound signals only by creating a deviation value graph. It is possible to reduce the processing required to specify the sound source direction.
  • the audio signal evaluation unit 5 acquires audio data stored in the first microphone signal storage unit 4a and the second microphone signal storage unit 4b (step S1; hereinafter abbreviated as S1).
  • the phase-shifted audio signal creating unit 51 of the audio signal evaluating unit 5 converts the phase-shifted audio signal in which the relative phase shift amount between the audio signals indicated by each of the two audio data is changed stepwise for each phase shift amount.
  • Create (S2) Then, the deviation value calculation unit 52 obtains an integrated value (deviation value) of the difference between the output values within a certain range of the two audio signals in the phase-shifted audio signal corresponding to each phase shift amount (S3), and the deviation value graph
  • the creating unit 53 creates a deviation value graph indicating the change of the deviation value with time (S4).
  • the determination unit 54 determines whether or not the audio signals output from the first microphone 2a and the second microphone 2b are appropriate for calculating the phase difference based on the deviation value graph created by the deviation value graph creation unit 53. judge. Specifically, the determination unit 54 determines whether or not the minimum value of the deviation value graph is larger than a predetermined threshold (S5). If the minimum value of the deviation value graph is larger than the predetermined threshold value, the determination unit 54 determines that the sound signals output from the first microphone 2a and the second microphone 2b are inappropriate for calculating the phase difference. Then, the process returns to S1, and the processing after S2 is performed again using another audio data.
  • S5 a predetermined threshold
  • the determination unit 54 specifies the number of local minimum points of the deviation value graph (S6). And the determination part 54 determines whether the number of the specified minimum points is one (S7). When the number of local minimum points in the deviation value graph is two or more, the determination unit 54 determines that the audio signals output from the first microphone 2a and the second microphone 2b are inappropriate for calculating the phase difference. Then, the process returns to S1, and the processing after S2 is performed again using another audio data.
  • the determination unit 54 determines that the audio signals output from the first microphone 2a and the second microphone 2b are appropriate for calculating the phase difference. . Then, the phase difference calculation unit 55 calculates the phase shift amount at the minimum value of the deviation value graph as the phase difference between the two audio signals indicated by the two audio data (S8).
  • the sound source direction specifying unit 6 specifies the sound source direction based on the phase difference calculated by the phase difference calculating unit 55 (S9). Specifically, the sound source direction identification unit 6 sends the phase difference calculated by the phase difference calculation unit 55 to the angle table 7 and receives the angle of the sound source direction corresponding to the phase difference from the angle table 7. Then, the sound source direction specifying unit 6 specifies the angle direction of the sound source from the angle obtained using the angle table 7, and outputs the specified angle direction to the outside as a detection result of the sound source direction (S10).
  • FIG. 13 is a block diagram showing the sound source direction detection device 11 according to the present embodiment.
  • the sound source direction detection device 11 includes a first microphone 2a, a second microphone 2b, a third microphone 2c, a first microphone signal input unit 3a, a second microphone signal input unit 3b, and a third microphone signal input.
  • the first microphone 2a, the second microphone 2b, the third microphone 2c, the first microphone signal input unit 3a, the second microphone signal input unit 3b, the third microphone signal input unit 3c, the first microphone signal storage unit 4a, the first microphone The 2 microphone signal storage unit 4b, the third microphone signal storage unit 4c, and the audio signal evaluation unit 5 function as the phase difference calculation device 20 according to the present invention.
  • the sound source direction detection device 11 is different from the sound source direction detection device 1 in that it includes a third microphone 2c, a third microphone signal input unit 3c, and a third microphone signal storage unit 4c.
  • the third microphone 2c is a microphone that converts external sound into an audio signal.
  • the 1st microphone 2a, the 2nd microphone 2b, and the 3rd microphone 2c are arranged in a mutually different position, and are arranged so that it may not be located on the same straight line.
  • the third microphone signal input unit 3c creates voice data in which the voice signal converted by the third microphone 2c is digitized.
  • the third microphone signal storage unit 4c stores the voice data created by the third microphone signal input unit 3c, and always stores voice data for an arbitrary fixed time.
  • the audio signal evaluation unit 5 Since the sound source direction detection device 11 has three microphones, that is, the first microphone 2a, the second microphone 2b, and the third microphone 2c, the audio signal evaluation unit 5 has a combination of two microphones out of the three microphones. In addition, the phase difference between the audio signals obtained from each microphone is calculated. That is, the audio signal evaluation unit 5 calculates the phase difference for each of the three combinations of microphones. In principle, the audio signal evaluation unit 5 may calculate the phase difference of at least two combinations of microphones.
  • the angle direction specified from the phase difference calculated by the audio signal evaluation unit 5 may be the left and right directions with respect to the straight line connecting the two microphones. For this reason, in the angular direction specified from one phase difference, it cannot be specified whether the sound source direction is the left and right directions with respect to the straight line connecting the two microphones.
  • the sound source direction specifying unit 6 specifies, as the sound source direction, the direction in which the angle direction specified from the phase difference coincides between at least two phase differences calculated by the audio signal evaluation unit 5. That is, the sound source direction specifying unit 6 specifies, as the sound source direction, a direction that matches one of the angle directions specified from the other phase difference among the angle directions specified from the one phase difference. The sound source direction specifying unit 6 outputs the specified sound source direction to the outside as a detection result.
  • the sound source direction detection device 11 can detect the sound source direction from all directions of 360 degrees on a plane including three microphones.
  • the use place is restricted such as being installed near a wall.
  • the use place is not restricted, and the sound source can be placed at a favorite place.
  • a direction detection device 11 can be installed.
  • two sound source direction detection devices 11 according to the second embodiment are used, and both are installed at locations separated from each other. Then, by using a triangulation method from the sound source direction detected by each sound source direction detection device 11, the distance from each sound source direction detection device to the sound source can be calculated, and the position of the sound source can be specified.
  • the position of the sound source can be detected by using the two sound source direction detection devices 11. That is, in this embodiment, the two sound source direction detection devices 11 can be used as the sound source position detection device.
  • FIG. 14 is a block diagram showing the sound source direction detection device 21 according to this embodiment.
  • the sound source direction detection device 21 includes a first microphone 2a, a second microphone 2b, a third microphone 2c, a fourth microphone 2d, a first microphone signal input unit 3a, a second microphone signal input unit 3b, Third microphone signal input unit 3c, fourth microphone signal input unit 3d, first microphone signal storage unit 4a, second microphone signal storage unit 4b, third microphone signal storage unit 4c, fourth microphone signal storage unit 4d, audio signal An evaluation unit 5, a sound source direction specifying unit 6, and an angle table 7 are provided.
  • the input unit 3d, the first microphone signal storage unit 4a, the second microphone signal storage unit 4b, the third microphone signal storage unit 4c, the fourth microphone signal storage unit 4d, and the audio signal evaluation unit 5 are phase differences according to the present invention. It functions as the calculation device 30.
  • the sound source direction detection device 21 is different from the sound source direction detection device 11 in that it includes a fourth microphone 2d, a fourth microphone signal input unit 3d, and a fourth microphone signal storage unit 4d.
  • the fourth microphone 2d is a microphone that converts external sound into an audio signal.
  • the 1st microphone 2a, the 2nd microphone 2b, the 3rd microphone 2c, and the 4th microphone 2d are arranged in a mutually different position, and are arranged so that it may not be located on the same plane.
  • the fourth microphone signal input unit 3d creates voice data obtained by digitizing the voice signal converted by the fourth microphone 2d.
  • the fourth microphone signal storage unit 4d stores the voice data created by the fourth microphone signal input unit 3d, and always stores voice data for an arbitrary fixed time.
  • FIG. 15 is a diagram for explaining a method of specifying a sound source direction using four microphones.
  • the fourth microphone 2d is arranged at a position perpendicular to the plane including the first microphone 2a, the second microphone 2b, and the third microphone 2c and on a straight line passing through the third microphone 2c.
  • the plane (the first microphone 2a, the second microphone 2b, and the third microphone 2c are replaced by the method described in the second embodiment).
  • the angle ⁇ 1 in the sound source direction is obtained.
  • the angle ⁇ 1 is an angle between a straight line passing through the first microphone 2a and the second microphone 2b in the plane.
  • the sound source direction with respect to the straight line (the straight line passing through the third microphone 2c and the fourth microphone 2d) is specified by the method described in the first embodiment.
  • the angle ⁇ 2 in the sound source direction is obtained.
  • the angle ⁇ 2 is an angle between the straight line. That is, the sound source direction is a direction passing through a conical surface having the above-mentioned straight line as a main axis and an apex angle of 2 ⁇ ⁇ 2.
  • the sound source direction can be specified from the three-dimensional vector of the polar coordinate system obtained from the two angles ⁇ 1 and ⁇ 2 obtained as described above.
  • the angle between the third microphone 2c and the straight line passing through the fourth microphone 2d is an angle ⁇ 2
  • the plane includes the first microphone 2a, the second microphone 2b, and the third microphone 2c.
  • the sound source direction specifying unit 6 outputs the sound source direction specified as described above to the outside as a detection result.
  • the sound source direction detection device 21 can detect the direction of the sound source position in the three-dimensional space instead of detecting the sound source direction on the plane.
  • the sound source is a human voice
  • the position of the mouth of the person talking can be detected including the height direction, so that the height can be known to some extent, which makes it possible to distinguish between adults and children. Will also be available.
  • Phase difference calculation apparatuses 10, 20, and 30 according to aspect 1 of the present invention are arranged at different positions, convert a sound from an external sound into a sound signal, and output one of the plurality of microphones.
  • a phase-shifted audio signal is created for each phase-shifted amount by gradually changing the relative phase-shifted amount between the audio signals output from one of the microphones and the audio signal output from the other microphones.
  • a phase shift audio signal creation unit 51 that performs an integrated value calculation unit that calculates an integrated value of a difference between output values within a certain range of two audio signals in the phase shift audio signal corresponding to each phase shift amount (deviation value) Based on the calculation unit 52), the audio signal output from the one microphone, and the audio signal output from the other microphone based on the integrated value It includes a phase difference calculator 55 for calculating a phase difference, a.
  • the phase difference between the two can be calculated.
  • the frequency component of human voice greatly fluctuates due to the pronunciation of words.
  • the sound signal may be intermittently generated due to mixing of other noise from the surroundings.
  • the phase difference calculation apparatus can calculate the phase difference between audio signals output from different microphones more accurately.
  • the phase difference calculation unit 55 is configured such that the accumulated value when the phase shift amount is changed stepwise. In such a change, the phase shift amount when the integrated value becomes the minimum is calculated as a phase difference between the audio signal output from the one microphone and the audio signal output from the other microphone.
  • the phase shift amount when the integrated value becomes the minimum is the time shift (phase difference) between the two audio signals. Therefore, in the above configuration, the integrated value is the smallest in the change over time of the integrated value when the audio signal output from the other microphone is phase-shifted with respect to the audio signal output from one microphone. Is calculated as the phase difference between the audio signals output by both microphones.
  • the phase difference calculation apparatuses 10, 20, and 30 according to the aspect 3 of the present invention are based on the time-dependent change in the integrated value when the phase shift amount is changed stepwise in the aspect 1 or 2.
  • the sound signal output from the microphone further includes a determination unit that determines whether or not the sound signal is appropriate for calculating the phase difference, and the phase difference calculation unit 55 includes the sound output from each microphone.
  • the determination unit 54 determines that the signal is appropriate for calculating the phase difference
  • the audio signal output from the one microphone and the other based on the change over time of the integrated value
  • the phase difference from the audio signal output by the microphone is calculated.
  • the determination unit 54 recognizes an audio signal inappropriate for calculating the phase difference, and the phase difference calculation unit 55 does not use the audio signal for calculating the phase difference.
  • the phase difference can be calculated using only an appropriate audio signal. Therefore, the phase difference calculation apparatuses 10, 20, and 30 according to one aspect of the present invention can calculate the phase difference more accurately.
  • the determination unit 54 determines that each of the microphones has a minimum point in the change with time of the integrated value. It is determined that the output audio signal is appropriate for calculating the phase difference.
  • phase difference is calculated only when there is one local minimum point in the temporal change in the integrated value, so that the phase difference can be calculated more accurately.
  • the determination unit 54 determines that the minimum value of the integrated value in the change over time of the integrated value is less than a predetermined threshold value. In this case, it is determined that the audio signal output from each microphone is appropriate for calculating the phase difference.
  • the phase difference is calculated only when the minimum value of the integrated value in the temporal change of the integrated value is less than a predetermined threshold value, and therefore the phase difference can be calculated more accurately. Can do.
  • the sound source direction detection devices 1, 11 and 21 according to aspect 6 of the present invention determine the sound source direction of the sound based on the phase difference calculated by the phase difference calculation devices 10, 20, and 30 according to aspects 1 to 5. Identify.
  • the sound source direction can be detected using the accurate phase difference calculated by the phase difference calculation devices 10, 20, and 30 according to one aspect of the present invention, a more accurate sound source Direction detection is possible.
  • the sound source direction detection devices 11 and 21 according to aspect 7 of the present invention include the three or more microphones in the aspect 6, and the phase difference calculating devices 20 and 30 output the three or more microphones. With respect to the audio signal, the phase difference is calculated, and the sound source direction is specified based on the two or more phase differences calculated by the phase difference calculation devices 20 and 30.
  • a phase difference calculation method includes a step of converting an external sound into an audio signal using a plurality of microphones arranged at different positions, and outputting one of the plurality of microphones. Creating a phase-shifted audio signal in which the relative phase shift amount between the audio signals output from the two microphones and the audio signals output from the other microphones are changed stepwise; A step of calculating an integrated value of a difference between output values within a predetermined range of the two audio signals in the phase-shifted audio signal corresponding to the phase shift amount; and the audio signal output from the one microphone based on the integrated value And calculating a phase difference with the audio signal output from the other microphone.
  • the present invention can be suitably used as a phase difference calculating device of a sound source direction detecting device used for a robot that talks with a human, a microphone unit of a telephone conference system, or a security monitoring system.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Circuit For Audible Band Transducer (AREA)
  • Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
  • Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)

Abstract

La présente invention calcule avec plus de précision la différence de phase entre des signaux audio délivrés en sortie par différents microphones. Une unité d'évaluation de signal audio (5) d'un dispositif de détection de direction de source sonore (1) crée des signaux audio de décalage de phase dans lesquels les quantités de décalage de phase relatif des signaux audio sortis par un premier microphone (2a) et un second microphone (2b) sont changées par étapes et calcule la différence de phase entre les deux signaux audio sur la base de la valeur intégrée des différences entre les valeurs de sortie des deux signaux audio à l'intérieur d'une plage fixe dans chaque signal audio de décalage de phase.
PCT/JP2015/064814 2014-07-25 2015-05-22 Dispositif de calcul de différence de phase, dispositif de détection de direction de source sonore, et procédé de calcul de différence de phase WO2016013286A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2014-152102 2014-07-25
JP2014152102A JP2016031243A (ja) 2014-07-25 2014-07-25 位相差算出装置、音源方向検知装置、および位相差算出方法

Publications (1)

Publication Number Publication Date
WO2016013286A1 true WO2016013286A1 (fr) 2016-01-28

Family

ID=55162823

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2015/064814 WO2016013286A1 (fr) 2014-07-25 2015-05-22 Dispositif de calcul de différence de phase, dispositif de détection de direction de source sonore, et procédé de calcul de différence de phase

Country Status (2)

Country Link
JP (1) JP2016031243A (fr)
WO (1) WO2016013286A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113763657A (zh) * 2020-06-04 2021-12-07 浙江宇视科技有限公司 监控警报装置、监控警报控制方法及监控系统
US11714158B2 (en) 2019-08-21 2023-08-01 University Of Washington Position determination systems and methods utilizing error of multiple candidate positions

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6988321B2 (ja) * 2017-09-27 2022-01-05 株式会社Ｊｖｃケンウッド 信号処理装置、信号処理方法、及びプログラム

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07287062A (ja) * 1994-04-18 1995-10-31 Sony Corp 音声方向センサ
JP2004077277A (ja) * 2002-08-19 2004-03-11 Fujitsu Ltd 音源位置の可視化表示方法および音源位置表示装置
JP2005049153A (ja) * 2003-07-31 2005-02-24 Toshiba Corp 音声方向推定装置及びその方法
WO2008056649A1 (fr) * 2006-11-09 2008-05-15 Panasonic Corporation Détecteur de position de source sonore
WO2008146565A1 (fr) * 2007-05-30 2008-12-04 Nec Corporation Procédé, dispositif et programme de détection de la direction d'une source sonore
JP2012226438A (ja) * 2011-04-15 2012-11-15 Toyota Motor Corp 接近車両検出装置及び接近車両検出方法
WO2013048708A1 (fr) * 2011-09-30 2013-04-04 Microsoft Corporation Positionnement basé sur un son

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07287062A (ja) * 1994-04-18 1995-10-31 Sony Corp 音声方向センサ
JP2004077277A (ja) * 2002-08-19 2004-03-11 Fujitsu Ltd 音源位置の可視化表示方法および音源位置表示装置
JP2005049153A (ja) * 2003-07-31 2005-02-24 Toshiba Corp 音声方向推定装置及びその方法
WO2008056649A1 (fr) * 2006-11-09 2008-05-15 Panasonic Corporation Détecteur de position de source sonore
WO2008146565A1 (fr) * 2007-05-30 2008-12-04 Nec Corporation Procédé, dispositif et programme de détection de la direction d'une source sonore
JP2012226438A (ja) * 2011-04-15 2012-11-15 Toyota Motor Corp 接近車両検出装置及び接近車両検出方法
WO2013048708A1 (fr) * 2011-09-30 2013-04-04 Microsoft Corporation Positionnement basé sur un son

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11714158B2 (en) 2019-08-21 2023-08-01 University Of Washington Position determination systems and methods utilizing error of multiple candidate positions
CN113763657A (zh) * 2020-06-04 2021-12-07 浙江宇视科技有限公司 监控警报装置、监控警报控制方法及监控系统

Also Published As

Publication number Publication date
JP2016031243A (ja) 2016-03-07

Similar Documents

Publication Publication Date Title
JP6289936B2 (ja) 音源方向推定装置、音源方向推定方法およびプログラム
US9282399B2 (en) Listen to people you recognize
US10225680B2 (en) Motion detection of audio sources to facilitate reproduction of spatial audio spaces
US20180137876A1 (en) Speech Signal Processing System and Devices
US20180249267A1 (en) Passive microphone array localizer
WO2016013286A1 (fr) Dispositif de calcul de différence de phase, dispositif de détection de direction de source sonore, et procédé de calcul de différence de phase
JP2006194700A (ja) 音源方向推定システム、音源方向推定方法及び音源方向推定プログラム
JP2008261688A (ja) 音源分離装置および音源分離方法
JP2005250397A (ja) ロボット
KR20220117282A (ko) 오디오 디바이스 자동-로케이션
WO2015142717A1 (fr) Utilisation d'ultrasons afin d'améliorer une détection de geste reposant sur une imu
JP2010181326A (ja) 超音波計測器
JP6697982B2 (ja) ロボットシステム
US10104489B2 (en) Method for using a mobile device equipped with at least two microphones for determining the direction of loudspeakers in a setup of a surround sound system
Al-Sheikh et al. Sound source direction estimation in horizontal plane using microphone array
JP2009236688A (ja) 音源方向検出方法、装置及びプログラム
KR100730297B1 (ko) 머리전달함수 데이터베이스를 이용한 음원 위치 추정 방법
JP2005049153A (ja) 音声方向推定装置及びその方法
JP2011033369A (ja) 会議装置
JP6433630B2 (ja) 雑音除去装置、エコーキャンセリング装置、異音検出装置および雑音除去方法
TWI402531B (zh) 音源辨位方法與應用此音源辨位方法之音源辨位系統和電腦程式產品
TWI577194B (zh) 環境音源辨識系統及其環境音源辨識之方法
Sledevič et al. An evaluation of hardware-software design for sound source localization based on SoC
TWI633275B (zh) 距離偵測裝置及其距離偵測方法
CN109375199B (zh) 距离检测装置及其距离检测方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15824335

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15824335

Country of ref document: EP

Kind code of ref document: A1