KR101943903B1 - Method for cognition direction of sound source, apparatus and system for executing the method - Google Patents

Abstract

Disclosed are a sound source direction recognizing method, and a device and a system for performing the same. According to an embodiment of the present invention, a sound source direction recognizing system comprises: a microphone configured to receive an acoustic signal generated from a sound source; a plurality of reflection plates prepared to have a different reflection distance from the microphone, separated from each other and configured to reflect the acoustic signal from the sound source; and a sound source direction recognizing module configured to recognize a direction of the sound source based on an acoustic signal (directly received acoustic signal) that the microphone directly receives from the sound source and an acoustic signal (reflectively received acoustic signal) that the microphone receives from the reflection plates. The present invention is suitable for recognizing a direction of the sound source through a microphone, so the sound source direction recognizing system can be miniaturized.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of recognizing a sound source direction and an apparatus and system for performing the same,

Embodiments of the invention relate to sound source direction recognition techniques.

Many studies have been conducted to recognize the direction of a sound source. However, existing studies have mainly recognized the direction of sound sources using two or more microphones. In this case, the number of hardware components of the system for recognizing the sound source direction increases, and the volume of the system itself becomes large. In addition, there is a problem that the amount of calculation processing for recognizing the direction of the sound source is increased.

Korean Patent Registration No. 10-0493172 (Jun. 2005)

An embodiment of the present invention is to provide a sound source direction recognition method capable of recognizing a direction of a sound source using one microphone, and an apparatus and system for performing the method.

According to another aspect of the present invention, there is provided a sound source direction recognition system including: a microphone for receiving an acoustic signal generated from a sound source; A plurality of reflection plates disposed to be spaced apart from each other with different reflection distances from the microphone and reflecting acoustic signals generated from the sound source; And a sound source direction recognition module for recognizing the direction of the sound source based on an acoustic signal (direct reception acoustic signal) directly received from the sound source by the microphone and an acoustic signal (reflection reception acoustic signal) received from the reflection plate by the microphone .

Each of the plurality of reflection plates may be provided perpendicularly to the ground toward the microphone.

The plurality of reflection plates may be disposed such that the center of the plurality of reflection plates facing the microphone has a predetermined angle interval with respect to the microphone.

The sound source direction recognition system may further include a plurality of connection units connecting the plurality of reflection plates to the microphone and having different lengths.

The sound source direction recognition system may further include a microphone housing part for housing the microphone, one end of the plurality of connection parts is connected to the plurality of reflection plates, and the other end of the plurality of connection parts is connected to the microphone housing part .

The other ends of the plurality of connection portions may be spaced apart from the outer circumferential surface of the microphone housing portion at predetermined angular intervals.

The plurality of connection portions may be formed to be longer from one side of the outer circumferential surface of the microphone housing portion toward the other.

The sound source direction recognition module may calculate a delay time between the direct reception sound signal and the reflection reception sound signal and recognize the direction of the sound source by checking a reflector having a reflection distance corresponding to the calculated delay time .

A method for recognizing a source direction according to an embodiment disclosed is a method performed in a computing device having one or more processors and a memory for storing one or more programs executed by the one or more processors, Calculating a Real Cepstrum of the acoustic signal (including the direct reception acoustic signal and the reflection reception acoustic signal); Filtering the real cepstrum to remove the direct received acoustic signal; Calculating a structure-related impulse response by taking an inverse cepstrum of the real cepstrum from which the direct reception acoustic signal is removed; And extracting a position at which the structure-related impulse response is minimum and calculating a delay time between the direct reception acoustic signal and the reflected reception acoustic signal based on a position at which the structure-related response pulse response is minimized .

Wherein the direct reception acoustic signal is an acoustic signal directly received from a sound source by the microphone and the reflection reception acoustic signal is generated by a reflection structure including a plurality of reflection plates arranged to be spaced apart from each other with a different reflection distance from the microphone And may be an acoustic signal reflected and received.

Determining a reflector having a reflection distance corresponding to the calculated delay time after calculating the delay time; And recognizing the direction of the sound source from the identified reflector.

The plurality of reflection plates may be disposed such that the center of the plurality of reflection plates facing the microphone has a predetermined angle interval with respect to the microphone.

A computing device according to one disclosed embodiment includes: one or more processors; Memory; And one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, wherein the one or more programs cause the sound signals received by the microphone A command to calculate a Real Cepstrum of the received signal (including a received acoustic signal); Instructions for filtering the real cepstrum to remove the direct received acoustic signal; A command for calculating a Structure Related Impulse Response by taking an Inverse Cepstrum of the real cepstrum from which the direct received acoustic signal is removed; And a command for calculating a delay time between the direct received acoustic signal and the reflected acoustic signal based on a position at which the structure-related impulse response is minimized and a position at which the structure- do.

Wherein the direct reception acoustic signal is an acoustic signal directly received from a sound source by the microphone and the reflection reception acoustic signal is generated by a reflection structure including a plurality of reflection plates arranged to be spaced apart from each other with a different reflection distance from the microphone And may be an acoustic signal reflected and received.

Wherein the one or more programs include: a command for confirming a reflector having a reflection distance corresponding to the calculated delay time; And an instruction to recognize the direction of the sound source from the identified reflector.

The plurality of reflection plates may be disposed such that the center of the plurality of reflection plates facing the microphone has a predetermined angle interval with respect to the microphone.

According to the disclosed embodiment, since the direction of a sound source can be recognized through a single microphone, the sound source direction recognition system can be miniaturized and the number of hardware parts can be reduced. In addition, the amount of computation for estimating the direction of a sound source can be reduced compared to a system using multiple microphones.

1 is a diagram illustrating a configuration of a sound source direction recognition system according to an embodiment of the present invention;
2 is a perspective view illustrating a reflection structure according to an embodiment of the present invention.
3 is a plan view showing a reflection structure according to an embodiment of the present invention.
4 is a flowchart illustrating a sound source direction recognition method according to an embodiment of the present invention.
5 is a block diagram illustrating and illustrating a computing environment including a computing device suitable for use in the exemplary embodiments.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. The following detailed description is provided to provide a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, this is merely an example and the present invention is not limited thereto.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. The following terms are defined in consideration of the functions of the present invention, and may be changed according to the intention or custom of the user, the operator, and the like. Therefore, the definition should be based on the contents throughout this specification. The terms used in the detailed description are intended only to describe embodiments of the invention and should in no way be limiting. Unless specifically stated otherwise, the singular form of a term includes plural forms of meaning. In this description, the expressions "comprising" or "comprising" are intended to indicate certain features, numbers, steps, operations, elements, parts or combinations thereof, Should not be construed to preclude the presence or possibility of other features, numbers, steps, operations, elements, portions or combinations thereof.

In the following description, terms such as " transmission ", "transmission "," transmission ", "reception ", and the like, of a signal or information refer not only to the direct transmission of signals or information from one component to another But also through other components. In particular, "transmitting" or "transmitting" a signal or information to an element is indicative of the final destination of the signal or information and not a direct destination. This is the same for "reception" of a signal or information. Also, in this specification, the fact that two or more pieces of data or information are "related" means that when one piece of data (or information) is acquired, at least a part of the other data (or information) can be obtained based thereon.

On the other hand, directional terms such as the top, bottom, one side, the other, and the like are used in connection with the orientation of the disclosed figures. Since the elements of the embodiments of the present invention can be positioned in various orientations, directional terms are used for illustrative purposes and not limitation.

Also, the terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms may be used for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

1 is a block diagram of a sound source direction recognition system according to an embodiment of the present invention.

Referring to FIG. 1, the sound source direction recognition system 100 may include a microphone 102, a reflection structure 104, and a sound source direction recognition module 106. The sound source direction recognition system 100 may be a system for recognizing the direction of the sound source 10 where sound is generated.

The microphone 102 may acquire an acoustic signal generated by the sound source 10. Here, the acoustic signal is a sound signal directly received from the sound source 10 (hereinafter referred to as a direct reception acoustic signal) and an acoustic signal (hereinafter referred to as a reflection reception acoustic signal) May be included). The sound source direction recognition system 100 can recognize the direction of the sound source 10 using one microphone 102. [ The microphone 102 may be disposed between the sound source 10 and the reflective structure 104.

The reflective structure 104 may include a plurality of reflectors coupled to the microphone 102. The plurality of reflection plates may be arranged at regular intervals. The reflection structure 104 may be provided to reflect the acoustic signal generated by the sound source 10 to the microphone 102. A detailed description of the structure of the reflective structure 104 will be given later with reference to FIGS. 2 and 3. FIG.

The sound source direction recognition module 106 can estimate the direction of the sound source 10 based on the sound signals (that is, the direct reception sound signal and the reflection reception sound signal) acquired by the microphone 102. Specifically, the sound source direction recognition module 106 can estimate the direction of the sound source 10 based on the time difference between the direct reception sound signal and the reflection reception sound signal and the placement direction of the plurality of reflection plates of the reflection structure 104 . A detailed description thereof will be given later with reference to FIG.

Herein, a module may mean a functional and structural combination of hardware for carrying out the technical idea of the present invention and software for driving the hardware. For example, the "module" may refer to a logical unit of a predetermined code and a hardware resource for executing the predetermined code, and it does not necessarily mean a physically connected code or a kind of hardware .

According to the disclosed embodiment, since the direction of the sound source 10 can be recognized through the single microphone 102, the sound source direction recognition system 100 can be miniaturized and the number of hardware parts can be reduced. In addition, the amount of computation for estimating the direction of a sound source can be reduced compared to a system using multiple microphones.

FIG. 2 is a perspective view showing a reflection structure according to an embodiment of the present invention, and FIG. 3 is a plan view showing a reflection structure according to an embodiment of the present invention.

Referring to FIGS. 2 and 3, the reflective structure 104 may include a first reflective plate 111 to a sixth reflective plate 116. Although the reflective structure 104 is described herein as including six reflective plates, the reflective structure 104 may include other various numbers of reflective plates.

The first reflection plate 111 to the sixth reflection plate 116 may be connected to the microphone 102 through the first connection part 121 to the sixth connection part 126, respectively. In the exemplary embodiment, the microphone 102 may be housed inside the microphone housing portion 102a. The microphone housing part 102a may be formed in a ring shape, but the shape is not limited thereto.

One end of the first connection part 121 to the sixth connection part 126 may be connected to the first reflection plate 111 to the sixth reflection plate 116, respectively. One end of the first connection part 121 to the sixth connection part 126 may be connected to the lower ends of the first reflection plate 111 to the sixth reflection plate 116, respectively. In this case, acoustic scattering between the reflective structure 104 and the microphone 102 can be minimized. The other ends of the first to fifth connection portions 121 to 126 may be connected to the outer circumferential surface of the microphone housing portion 102a, respectively.

The first to sixth connecting portions 121 to 126 may be spaced apart from each other by a predetermined angle interval from the outer circumferential surface of the microphone housing portion 102a. In an exemplary embodiment, the first to sixth connections 121 to 126 may be sequentially spaced apart at 10 degree intervals. For example, when the first connection part 121 is used as a reference (that is, when the first connection part 121 is 0 degree), the second connection part 122 is spaced apart from the first connection part 121 by 10 degrees The third connection part 123 is spaced apart from the first connection part 121 by an interval of 20 degrees and the fourth connection part 124 is spaced apart from the first connection part 121 by an interval of 30 degrees, The fifth connection part 125 may be spaced apart from the first connection part 121 by 40 degrees and the sixth connection part 126 may be spaced apart from the first connection part 121 by 50 degrees.

In addition, the first to sixth connecting portions 121 to 126 may have different lengths. In the exemplary embodiment, the length may be increased as the distance from the first connection part 121 to the sixth connection part 126 increases. At this time, it may be provided to be longer by a certain length from the first connection part 121 to the sixth connection part 126. [ For example, the first connection part 121 is 15 cm, the second connection part 122 is 16 cm, the third connection part 123 is 17 cm, the fourth connection part 124 is 18 cm, the fifth connection part 125 is 19 cm, 6 connection portion 126 may be formed to be longer by a predetermined length (1 cm) from the first connection portion 121 to the sixth connection portion 126, such as 20 cm. The lengths of the first to sixth connecting portions 121 to 126 may be the distance between the first to sixth reflecting plates 111 to 116 and the microphone 102, respectively.

The first reflection plate 111 to the sixth reflection plate 116 may be formed perpendicular to the paper surface at one end of the first connection part 121 to the sixth connection part 126. The first reflection plate 111 to the sixth reflection plate 116 may be provided to face the microphone 102, respectively. That is, the first to sixth reflection plates 111 to 116 may be provided perpendicular to the first to sixth connection units 121 to 126, respectively. The first reflection plate 111 to the sixth reflection plate 116 may be rectangular plates, but the shape of the reflection plates is not limited thereto.

The first to sixth reflective plates 111 to 116 have reflection distances corresponding to the lengths of the first to sixth connection portions 121 to 126, respectively. Here, the reflection distance may mean the distance between the reflection plates 111 to 116 and the microphone 102. The first to sixth reflectors 111 to 126 also correspond to the first to fifth connection portions 121 to 126 spaced apart from each other by a predetermined angle interval from the outer surface of the microphone housing portion 102a, Are spaced away from the microphone housing part 102a at regular angular intervals.

The first reflection plate 111 to the sixth reflection plate 116 may be fixed to the ground vertically without a separate connection part.

4 is a flowchart illustrating a sound source direction recognition method according to an embodiment of the present invention. In the illustrated flow chart, the method is described as being divided into a plurality of steps, but at least some of the steps may be performed in reverse order, combined with other steps, performed together, omitted, divided into detailed steps, One or more steps may be added and performed.

Referring to FIG. 4, the sound source direction recognition module 106 calculates a real cepstrum of the sound signal received by the microphone 102 (S101). Here, the acoustic signal received by the microphone 102 may include a direct reception acoustic signal and a reflection reception acoustic signal.

The acoustic signal y [n] received by the microphone 102 is a convolution of the original signal x [n] generated by the sound source 10 and the transfer function h [n]. That is, the sound source direction recognition module 106 can calculate the sound signal received by the microphone 102 through the following equation (1).

(1)

x [n]: the original signal generated in the sound source 10

h [n] is the transfer function of the space in which the sound source 10, the microphone 102, and the reflective structure 104 are located

The sound source direction recognition module 106 can calculate the real cepstrum c _y [n] of the sound signal y [n] received by the microphone 102 through the following equation (2) have.

(2)

DFT: Discrete Fourier Transform

IDFT: Inverse Discrete Fourier Transform (IDFT)

Next, the sound source direction recognition module 106 filters the real sound stream c _y [n] of the sound signal received by the microphone 102 to remove the direct received sound signal (S 103). In an exemplary embodiment, the sound source direction recognition module 106 applies a window to the real cepstrum c _y [n] as shown in Equation 3 below to remove the direct received sound signal, The receiving acoustic signal can be left.

(3)

c _u [n] is the real cepstrum from which the direct receive acoustic signal is removed

w [n]: Window filter for removing direct received acoustic signals from real instruments

The window filter (w [n]) can be used with various types of filters to remove the received acoustic signal directly from the real cepstrum.

Next, the sound source direction recognition module 106 takes an Inverse Cepstrum of the real cepstrum c _u [n] from which the direct reception sound signal has been removed and outputs a Structure Related Impulse Response (S105). The sound source direction recognition module 106 can calculate the structure-related impulse response s [n] through the following expression (4).

(4)

DFT: Discrete Fourier Transform

IDFT: Inverse Discrete Fourier Transform (IDFT)

The structure-related impulse response s [n] may be related to the time difference between the direct reception acoustic signal and the reflection reception acoustic signal due to the autocorrelation characteristic of the transfer function h [n].

Next, the sound source direction recognition module 106 extracts a position at which the structure-related impulse response becomes minimum and calculates a delay time based on the position where the structure-related impulse response becomes minimum (i.e., Is calculated (S 107). The sound source direction recognition module 106 can calculate the delay time td through the following expression (5).

(5)

r: the position where the structure-related impulse response is minimized

fs: Sampling frequency

Next, the sound source direction recognition module 106 calculates the reflection distance of the corresponding reflected reception sound signal based on the delay time (i.e., the time difference between the direct reception sound signal and the reflection reception sound signal) (S 109). That is, the sound source direction recognition module 106 can calculate the reflection distance of the corresponding reflected reception sound signal by multiplying the delay time td by the sound velocity.

Next, the sound source direction recognition module 106 confirms the reflection plate corresponding to the calculated reflection distance and estimates the direction of the sound source 10 (S 111). That is, since the first to sixth reflectors 111 to 116 have different reflection distances, it is possible to identify the reflectors corresponding to the reflection distances calculated in step S 109. The sound source direction recognition module 106 can estimate that the direction in which the identified reflector faces is the direction of the sound source 10.

5 is a block diagram illustrating and illustrating a computing environment 10 including a computing device suitable for use in the exemplary embodiments. In the illustrated embodiment, each of the components may have different functions and capabilities than those described below, and may include additional components in addition to those described below.

The illustrated computing environment 10 includes a computing device 12. In one embodiment, the computing device 12 may be an apparatus (e.g., sound source direction recognition module 106) for recognizing the source direction.

The computing device 12 includes at least one processor 14, a computer readable storage medium 16, The processor 14 may cause the computing device 12 to operate in accordance with the exemplary embodiment discussed above. For example, processor 14 may execute one or more programs stored on computer readable storage medium 16. The one or more programs may include one or more computer-executable instructions, which when executed by the processor 14 cause the computing device 12 to perform operations in accordance with the illustrative embodiment .

The computer-readable storage medium 16 is configured to store computer-executable instructions or program code, program data, and / or other suitable forms of information. The program 20 stored in the computer-readable storage medium 16 includes a set of instructions executable by the processor 14. In one embodiment, the computer-readable storage medium 16 may be any type of storage medium such as a memory (volatile memory such as random access memory, non-volatile memory, or any suitable combination thereof), one or more magnetic disk storage devices, Memory devices, or any other form of storage medium that can be accessed by the computing device 12 and store the desired information, or any suitable combination thereof.

Communication bus 18 interconnects various other components of computing device 12, including processor 14, computer readable storage medium 16.

The computing device 12 may also include one or more input / output interfaces 22 and one or more network communication interfaces 26 that provide an interface for one or more input / output devices 24. The input / output interface 22 and the network communication interface 26 are connected to the communication bus 18. The input / output device 24 may be connected to other components of the computing device 12 via the input / output interface 22. The exemplary input and output device 24 may be any type of device, such as a pointing device (such as a mouse or trackpad), a keyboard, a touch input device (such as a touch pad or touch screen), a voice or sound input device, An input device, and / or an output device such as a display device, a printer, a speaker, and / or a network card. The exemplary input and output device 24 may be included within the computing device 12 as a component of the computing device 12 and may be coupled to the computing device 12 as a separate device distinct from the computing device 12 It is possible.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, . Therefore, the scope of the present invention should not be limited to the above-described embodiments, but should be determined by equivalents to the appended claims, as well as the appended claims.

100: Sound source direction recognition system
102: microphone
102a: Microphone compartment
104: reflective structure
106: sound source direction recognition module
111: first reflector
112: second reflector
113: Third reflector
114: fourth reflector
115: fifth reflector
116: sixth reflector
121: first connection part
122: second connection portion
123: third connection portion
124: fourth connection part
125: fifth connection portion
126: sixth connection

Claims (17)

A microphone for receiving an acoustic signal generated from a sound source;
A plurality of reflection plates disposed to be spaced apart from each other with different reflection distances from the microphone and reflecting acoustic signals generated from the sound source; And
And a sound source direction recognition module for recognizing the direction of the sound source based on an acoustic signal (direct reception acoustic signal) directly received from the sound source by the microphone and an acoustic signal (reflection reception acoustic signal) received from the reflection plate by the microphone and,
The plurality of reflectors may include a plurality of reflectors,
And is perpendicular to the ground toward the microphone.
delete The method according to claim 1,
The plurality of reflectors may include a plurality of reflectors,
Wherein a center of the microphone toward the microphone is disposed at a predetermined angle interval with respect to the microphone.
A microphone for receiving an acoustic signal generated from a sound source;
A plurality of reflection plates disposed to be spaced apart from each other with different reflection distances from the microphone and reflecting acoustic signals generated from the sound source; And
A sound source direction recognition module for recognizing the direction of the sound source based on an acoustic signal (direct reception acoustic signal) directly received from the sound source by the microphone and an acoustic signal (reflection reception acoustic signal) received from the reflection plate by the microphone; And
And a plurality of connectors connecting the plurality of reflection plates to the microphone and having different lengths.
The method of claim 4,
Wherein the sound source direction recognition system comprises:
Further comprising a microphone housing portion for housing the microphone,
Wherein one end of each of the plurality of connection portions is connected to the plurality of reflection plates, and the other end of the plurality of connection portions is connected to the microphone storage portion.
The method of claim 5,
And the other ends of the plurality of connection portions are connected to each other,
Wherein the sound source direction recognition unit is spaced apart from the outer circumferential surface of the microphone storage unit at a predetermined angular interval.
The method of claim 6,
Wherein the plurality of connection portions comprise:
And a length of the microphone is increased from one side of the outer circumference of the microphone housing part to the other side.
A microphone for receiving an acoustic signal generated from a sound source;
A plurality of reflection plates disposed to be spaced apart from each other with different reflection distances from the microphone and reflecting acoustic signals generated from the sound source; And
And a sound source direction recognition module for recognizing the direction of the sound source based on an acoustic signal (direct reception acoustic signal) directly received from the sound source by the microphone and an acoustic signal (reflection reception acoustic signal) received from the reflection plate by the microphone and,
Wherein the sound source direction recognition module comprises:
And calculates a delay time between the direct reception acoustic signal and the reflected reception acoustic signal and identifies a direction of the sound source by checking a reflection plate having a reflection distance corresponding to the calculated delay time.
One or more processors, and
A method performed in a computing device having a memory storing one or more programs executed by the one or more processors,
Calculating a Real Cepstrum of the acoustic signal (including the direct reception acoustic signal and the reflection reception acoustic signal) received by the microphone;
Filtering the real cepstrum to remove the direct received acoustic signal;
Calculating a structure-related impulse response by taking an inverse cepstrum of the real cepstrum from which the direct reception acoustic signal is removed; And
Extracting a position at which the structure-related impulse response becomes minimum and calculating a delay time between the direct reception acoustic signal and the reflection reception acoustic signal based on a position at which the structure-related impulse response becomes minimum, Directional recognition method.
The method of claim 9,
The direct reception acoustic signal is an acoustic signal directly received by the microphone from the sound source,
Wherein the reflection reception acoustic signal is an acoustic signal reflected and received from a reflection structure including a plurality of reflection plates arranged to be spaced apart from each other and having different reflection distances from the microphone.
The method of claim 10,
After calculating the delay time,
Confirming a reflector having a reflection distance corresponding to the calculated delay time; And
And recognizing the direction of the sound source from the identified reflector.
The method of claim 11,
The plurality of reflectors may include a plurality of reflectors,
Wherein a center of the microphone toward the microphone is disposed at a predetermined angle interval with respect to the microphone.
One or more processors;
Memory; And
Comprising one or more programs,
Wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors,
The one or more programs,
A command for calculating a Real Cepstrum of the acoustic signal (including the direct reception acoustic signal and the reflection reception acoustic signal) received by the microphone;
Instructions for filtering the real cepstrum to remove the direct received acoustic signal;
A command for calculating a Structure Related Impulse Response by taking an Inverse Cepstrum of the real cepstrum from which the direct received acoustic signal is removed; And
Extracting a position at which the structure-related impulse response becomes minimum and calculating a delay time between the direct reception acoustic signal and the reflected reception acoustic signal based on a position at which the structure-related impulse response is minimized. Computing device.
14. The method of claim 13,
The direct reception acoustic signal is an acoustic signal directly received by the microphone from the sound source,
Wherein the reflection reception acoustic signal is an acoustic signal reflected and received from a reflection structure including a plurality of reflection plates disposed to be spaced apart from each other and having different reflection distances from the microphone.
15. The method of claim 14,
The one or more programs,
A command for confirming a reflector having a reflection distance corresponding to the calculated delay time; And
Further comprising instructions for recognizing a direction of the sound source from the identified reflector.
15. The method of claim 14,
The plurality of reflectors may include a plurality of reflectors,
Wherein a center of the microphone toward the microphone is arranged to have a predetermined angular interval with respect to the microphone.
A computer program stored on a non-transitory computer readable storage medium,
The computer program comprising one or more instructions that when executed by a computing device having one or more processors causes the computing device to:
Calculating a Real Cepstrum of the acoustic signal (including the direct reception acoustic signal and the reflection reception acoustic signal) received by the microphone;
Filtering the real cepstrum to remove the direct received acoustic signal;
Calculating a structure-related impulse response by taking an inverse cepstrum of the real cepstrum from which the direct reception acoustic signal is removed; And
Extracting a position at which the structure-related impulse response becomes minimum, and calculating a delay time between the direct reception acoustic signal and the reflected reception acoustic signal based on a position where the structure-related impulse response becomes minimum, Computer program.

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