Abstract:
A method comprising: detect a first acoustic signal by using a microphone array; detecting a first angle associated with a first incident direction of the first acoustic signal; and storing, in a memory, a representation of the first acoustic signal and a representation of the first angle.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This is a Continuation application of U.S. patent application Ser. No. 14/840,336 filed on Aug. 31, 2015 which claims priority from and the benefit under 35 U.S.C. §119(a) of Korean Patent Application No. 10-2014-0115394, filed on Sep. 1, 2014, which is hereby incorporated by reference for all purposes as if fully set forth herein. 
    
    
     BACKGROUND 
     1. Field of the Disclosure 
     The present disclosure relates to electronic devices, and more particularly to a method and apparatus for managing audio signals. 
     2. Description of the Prior Art 
     Recently, the electronic device has provided a function to record another party&#39;s voice at the usual time or during a phone call, as well as basic functions, such as telephony or sending messages, to a user. 
     The electronic device includes a microphone for voice recording. The electronic device includes a plurality of microphones in order to thoroughly record audio signals. The plurality of microphones recognizes the direction of a speaker, and implements beams in the direction to thereby thoroughly record a voice that comes from the direction of the speaker. The beams may be implemented by applying a weight value to the microphones in order to increase the amplitude of the audio signal. 
     SUMMARY 
     According to one aspect of the disclosure, a method is provided comprising: detecting a first acoustic signal by using a microphone array; detecting a first angle associated with a first incident direction of the first acoustic signal; and storing, in a memory, a representation of the first acoustic signal and a representation of the first angle. 
     According to another aspect of the disclosure, an electronic device is provided comprising: a microphone array; a memory; a speaker; and at least one processor configured to: detect a first acoustic signal by using a microphone array; detect a first angle associated with a first incident direction of the first acoustic signal; and store, in a memory, a representation of the first acoustic signal and a representation of the first angle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above features and advantages of the present disclosure will be more apparent from the following detailed description in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a block diagram of an example of an electronic device, according to various embodiments of the present disclosure; 
         FIG. 2  is a flowchart of an example of a process, according to embodiments of the present disclosure; 
         FIG. 3  is a flowchart of an example of a process, according to various embodiments of the present disclosure; 
         FIG. 4  is a diagram of an example of a system implementing the process of  FIG. 3 , according to various embodiments of the present disclosure; 
         FIG. 5  is a diagram of an example of a stored audio signal, according to various embodiments of the present disclosure; 
         FIG. 6  is a diagram of an example of a system for rendering audio, according to various embodiments of the present disclosure; 
         FIG. 7  is a diagram illustrating an example of a rendered audio signal, according to various embodiments of the present disclosure; 
         FIG. 8  is a flowchart of an example of a process, according to various embodiments of the present disclosure; 
         FIG. 9  is a diagram of an example of a system implementing the process of  FIG. 8 , according to various embodiments of the present disclosure; 
         FIG. 10  is a diagram of an example of a stored audio signal according to various embodiments of the present disclosure; 
         FIG. 11  is a diagram of a system for rendering recorded audio signals, according to various embodiments of the present disclosure; 
         FIG. 12  is a flowchart of an example of a process, according to various embodiments of the present disclosure; 
         FIG. 13  is a diagram of an example of a system implementing the process of  FIG. 12 , according to various embodiments of the present disclosure; 
         FIG. 14  is a diagram of a stored audio signal, according to various embodiments of the present disclosure; 
         FIG. 15  is a diagram of an example of a system for rendering a stored audio signal, according to various embodiments of the present disclosure; 
         FIG. 16  is a diagram illustrating an example a process for recording audio, according to various embodiments of the present disclosure; 
         FIG. 17  is a diagram of an example of a user interface for rendering audio, according to various embodiments of the present disclosure; 
         FIG. 18  is a diagram of an example of a user interface for rendering audio, according to various embodiments of the present disclosure; 
         FIG. 19  is a diagram of an example of a user interface for rendering audio, according to various embodiments of the present disclosure; 
         FIG. 20  is a diagram illustrating an example of a process for recording audio, according to various embodiments of the present disclosure; and 
         FIG. 21  is a diagram of an example of a user interface for rendering audio, according to various embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It will be easily appreciated by those skilled in the art that various modifications, additions and substitutions are possible in the embodiments disclosed herein, and that the scope of the disclosure should not be limited to the following embodiments. The embodiments of the present disclosure are provided such that those skilled in the art completely understand the disclosure. In the drawings, the same or similar elements are denoted by the same reference numerals even though they are depicted in different drawings. 
     The expressions such as “include” and “may include” which may be used in the present disclosure denote the presence of the disclosed functions, operations, and constituent elements and do not limit one or more additional functions, operations, and constituent elements. In the present disclosure, the terms such as “include” and/or “have” may be construed to denote a certain characteristic, number, step, operation, constituent element, component or a combination thereof, but may not be construed to exclude the existence of or a possibility of the addition of one or more other characteristics, numbers, steps, operations, constituent elements, components or combinations thereof. 
     In the present disclosure, the expression “and/or” includes any and all combinations of the associated listed words. For example, the expression “A and/or B” may include A, may include B, or may include both A and B. 
     In the present disclosure, expressions including ordinal numbers, such as “first” and “second,” etc., and/or the like, may modify various elements. However, such elements are not limited by the above expressions. For example, the above expressions do not limit the sequence and/or importance of the elements. The above expressions are used merely for the purpose of distinguishing an element from the other elements. For example, a first user device and a second user device indicate different user devices although for both of them the first user device and the second user device are user devices. For example, a first element could be termed a second element, and similarly, a second element could be also termed a first element without departing from the scope of the present disclosure. 
     When a component is referred to as being “connected to” or “accessed by” another component, it should be understood that not only the component is directly connected or accessed to the other component, but also another component may exist between the component and the other component. Meanwhile, when a component is referred to as being “directly connected” or “directly accessed” to other component, it should be understood that there is no component therebetween. 
     The terms used in the present disclosure are only used to describe specific various embodiments, and are not intended to limit the present disclosure. Singular forms are intended to include plural forms unless the context clearly indicates otherwise. 
     Unless otherwise defined, all terms including technical and/or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosure pertains. In addition, unless otherwise defined, all terms defined in generally used dictionaries may not be overly interpreted. 
     For example, the electronic device corresponds to a combination of at least one of the followings: a smartphone, a tablet Personal Computer (PC), a mobile phone, a video phone, an e-book reader, a desktop PC, a laptop PC, a netbook computer, a Personal Digital Assistant (PDA), a Portable Multimedia Player (PMP), a digital audio player (e.g., MP3 player), a mobile medic device, a camera, or a wearable device. Examples of the wearable device are a head-mounted-device (HMD) (e.g., electronic eyeglasses), electronic clothing, an electronic bracelet, an electronic necklace, an appcessory, an electronic tattoo, a smart watch, etc. 
     The electronic device according to the embodiments of the present disclosure may be smart home appliances. Examples of the smart home appliances are a television (TV), a Digital Video Disk (DVD) player, an audio system, a refrigerator, an air-conditioner, a cleaning device, an oven, a microwave oven, a washing machine, an air cleaner, a set-top box, a TV box (e.g., Samsung HomeSync™, Apple TV™, or Google TV™, a game console, an electronic dictionary, an electronic key, a camcorder, an electronic album, or the like. 
     The electronic device according to the embodiments of the present disclosure may include at least one of the following: medical devices (e.g., Magnetic Resonance Angiography (MRA), Magnetic Resonance Imaging (MRI), Computed Tomography (CT), a scanning machine, an ultrasonic scanning device, etc.), a navigation device, a Global Positioning System (GPS) receiver, an Event Data Recorder (EDR), a Flight Data Recorder (FDR), a vehicle infotainment device, an electronic equipment for ships (e.g., navigation equipment, gyrocompass, etc.), avionics, a security device, a head unit for vehicles, an industrial or home robot, an automatic teller&#39;s machine (ATM), a point of sales (POS) system, etc. 
     The electronic device according to the embodiments of the present disclosure may include at least one of the following: furniture or a portion of a building/structure, an electronic board, an electronic signature receiving device, a projector, various measuring instruments (e.g., a water meter, an electric meter, a gas meter and a wave meter), etc. respectively. The electronic device according to the embodiments of the present disclosure may also include a combination of the devices listed above. In addition, the electronic device according to the embodiments of the present disclosure may be a flexible device. It is obvious to those skilled in the art that the electronic device according to the embodiments of the present disclosure is not limited to the aforementioned devices. 
     Hereinafter, electronic devices according the embodiments of the present disclosure are described in detail with reference to the accompanying drawings. In the description, the term a ‘user’ may be referred to as a person or a device that uses an electronic device, e.g., an artificial intelligent electronic device. 
       FIG. 1  is a block diagram of an example of an electronic device, according to various embodiments of the present disclosure. Referring to  FIG. 1 , the electronic device  100  may include a controller  110 , a microphone unit  130 , a speaker  140 , a memory  160 , and a communication unit  180 . The controller  110  may control overall operations of the electronic device  100  and the signal traffic between internal elements of the electronic device  100 , and may perform a data processing function. For example, the controller  110  may be formed of a central processing unit (CPU), or an application processor (AP). In addition, the controller  110  may be formed of a single-core processor, or a multi-core processor. 
     The controller  110  may include at least one processor. Each of the processors may include any combination of: one or more general-purpose processors (e.g., ARM-based processors, multi-core processors, etc.), a Field-Programmable Gate Array (FPGA), an Application-Specific Integrated Circuit (ASIC), a Digital Signal Processor (DSP), a Programmable Logic Device (PLD), and/or any other suitable type of processing circuitry. Additionally or alternatively, the controller  110 , may include a speaker position detecting unit  111 , a beamformer  113 , a pulse-code-modulation (PCM) file creating unit  117 , a coder  121 , a decoder  123 , and a user angle selecting unit  127 . 
     The speaker position detecting unit  111  may find the direction of an audio signal that has the highest level of energy from among audio signals received from a plurality of microphones  130 . Here, the direction may be angle information. The speaker position detecting unit  111  may recognize the direction to which the speaker currently speaks, using energy information, phase information, or correlation information between the microphones. When a plurality of speakers simultaneously speak, the speaker position detecting unit  111  may recognize the angle information in order of the intensity of energy of the audio signals created by the speakers. 
     The beamformer  113  may give weight values to the microphones to increase the amplitude of the audio signal so that beams, which are able to spatially reduce the related noise when the direction of the audio signal and the direction of the noise are different from each other. 
     With regard to the formation of the beams, a sound wave created in the sound source travels a different distance to each microphone. Since the sound wave has a limited speed, the sound wave will reach each microphone at a different time instant. However, apart from the time difference, the sound waves created from the same sound source may be recognized as the same wave at each microphone. Therefore, if the position of the sound source is given, the arriving time difference of the sound wave may be calculated for the correction thereof to thereby make the waves match each other. 
     The PCM file creating unit  117  may convert the audio signals input from a plurality of microphones  130  into PCM files. Here, the PCM file refers to the file that is stored as a digital signal converted from an analog signal, i.e., the audio signal. If the analog signal is stored without the conversion, it may be affected by the noise, so the analog signal is to be converted into the digital signal to then be stored. The created PCM file may be transmitted to a D/A converter. The D/A converter may convert the digital signal into the analog signal. The PCM file may be converted into the analog file through the D/A converter, and the converted audio signal may be finally transmitted to the speaker  140  to be thereby output to the user. 
     The coder  121  may store the recorded audio signal as a compressed file using a codec in order to reduce the storage capacity of the audio signal that has been converted into the digital signal. The coder  121  may receive the angle information corresponding to the speaker from the speaker position detecting unit  111 , and may store the same together with the recorded audio signal corresponding thereto. 
     The decoder  123  may decompress the file compressed through the coder  121 . The user angle selecting unit  127  may recognize the angle selection of the user. The user angle selecting unit  127  may recognize the speaker selection of the user as well as the angle selection. If the user wishes to hear the audio signal of the speaker “B,” or the audio signal of 90° that is mapped with the speaker “B,” the user angle selecting unit  127  may select the speaker “B,” or 90°. The user may select the same in a list or through a specific user interface (UI). 
     The microphone unit  130  may include a plurality of microphones. One or more microphones may receive the audio signals. The received audio signal may be recorded by the controller  110 , and may be used in calculating the position of the speaker. 
     The speaker  140  may reproduce the audio signal received through at least one microphone. The audio signal may be reproduced by the instruction of the controller  110  according to the user&#39;s selection. 
     A touch screen  150  may receive the angle information from the user angle selecting unit  127  of the controller  110 , and may display the same. Here, the angle information is stored as a file in the memory  160  together with the audio signal corresponding thereto. The touch screen  150  may detect the user&#39;s selection for one or more of the displayed angles, and may transfer the selected angle to the user angle selecting unit  127 . 
     In addition, the touch screen  150  may receive a recorded audio signal list from the controller  110 . The touch screen  150  may display the received recorded audio signal list. The touch screen  150  may receive text which is generated based on the audio signal associated with a specific speaker. The text may be generated by using a text-to-speech (TTS) by the controller  110 . The recorded audio signal list may permit the user to the content of each audio signal. 
     The memory  160  may include at least one of an internal memory or an external memory. The internal memory, for example, may include at least one of a volatile memory {e.g., a DRAM (dynamic random access memory), an SRAM (static random access memory), an SDRAM (synchronous dynamic random access memory, or the like}, a non-volatile memory {e.g., an OTPROM (one time programmable read-only memory), a PROM (programmable read-only memory), an EPROM (erasable and programmable read-only memory), an EEPROM (electrically erasable and programmable read-only memory), a mask read-only memory, a flash read-only memory, or the like}, an HDD (hard disk drive), or a solid-state drive (SSD). The external memory may include at least one of a CF (compact flash), SD (secure digital), Micro-SD (micro secure digital), Mini-SD (mini secure digital), xD (extreme digital), a memory stick, a network-accessible storage (NAS), a cloud storage or the like. The memory  160  may store the audio file compressed by the coder  121 . 
     The communication unit  180  may connect the electronic device  100  with external electronic devices. For example, the communication unit  180  may be connected to a network through wireless or wired communication to thereby communicate with the external electronic devices. The wireless communication may include Wi-Fi, BT (Bluetooth), NFC (near field communication), or the like. In addition, the wireless communication may include at least one selected from among the cellular communication networks (e.g., LTE, LTE-A, CDMA, WCDMA, UMTS, WiBro, GSM, or the like). For example, the wired communication may include at least one of a USB (universal serial bus), an HDMI (high definition multimedia interface), RS-232 (recommended standard 232), or a POTS (plain old telephone service). 
       FIG. 2  is a flowchart of an example of a process, according to embodiments of the present disclosure. Referring to  FIG. 2 , the controller  110  may recognize a user&#39;s request to begin the audio recording. In operation  203 , the controller  110  may identify a plurality of angles. For example, the plurality of angles may be the angles of audio signals to be received. In some implementations, the controller  110  may map each of the received audio signals to a different one of a plurality of angles at an interval of 90 degrees, i.e., at the angles of 0°, 90°, 180°, and 270°, to thereby store the same. For example, the controller  110  may receive the audio signals from four microphones to detect the position of the speaker using energy information, phase information, or correlation information between the microphones. In instances in which the controller  110  recognizes that the position of the speaker is 80°, the controller  110  may configure the position of the speaker as 90°, which is the relatively approximate value compared with other angles. 
     In operation  205 , the controller  110  may receive a plurality of audio signals through a plurality of microphones of the microphone unit  130 . 
     In operation  207 , the controller  110  may extract the audio signal that has the highest level of energy from the plurality of audio signals received from the plurality of microphones to thereby detect the angle of the audio signal. In operation  207 , the controller  110  may map the detected angle to one of the plurality of angles identified in operation  203 . For example, if the controller  110  determines that the audio signal having the highest level of energy is received at an angle of 160°, the controller  110  may map the audio signal with 180°, which is the approximate value compared to other angles. 
     In operation  209 , the controller  110  may determine whether angles in the plurality identified in operation  203  have not been processed yet. For example, since the controller  110  configures that four audio signals are to be received at an interval of 90° in operation  203 , the controller  110 , which has received one audio signal in operation  207 , may determine that there are three audio signals that have not yet been detected. If it is determined that there are angles that have not yet been processed, the controller  110  may proceed to operation  211 . In operation  211 , the controller  110  may detect the angle of the audio signal that has the highest level of energy from among the remaining audio signals rather than the detected audio signal. For example, if the angle of the detected audio signal is 90°, the audio signal may be mapped with 90°. 
     The controller  110  may return to operation  209  after detecting the angle of the audio signal that has the highest energy level from among the remaining audio signals in operation  211 . 
     The controller  110  may repeat the operation above, and if all of the configured angles are detected, that is, if it is determined that no angle that is not detected exists, the controller  110  may terminate the operation. 
       FIG. 3  is a flowchart of an example of a process, according to various embodiments of the present disclosure.  FIG. 4  is a diagram of an example of a system implementing the process of  FIG. 3 , according to various embodiments of the present disclosure. 
     The operation of  FIG. 3  will be described in association with the signal flow of  FIG. 4 . In operation  301 , the controller  110  may begin recording audio. For example, the controller  110  may recognize a user&#39;s request to begin the audio recording. Three microphones of the microphone unit  130  shown in  FIG. 4  are used. Three A/D converters  410  may convert the audio signals received from the plurality of microphones into the digital files. The three A/D converters  410  may transfer the audio signals, which have been converted into the digital files, to the controller  110 . 
     In operation  303 , the controller  110  may detect the position of the speaker. That is, the controller  110  may recognize the angle corresponding to the audio signal, when the audio signal is received. In operation  305 , the controller  110  may select one of the three microphones. Here, the microphones may be omnidirectional microphones. In operation  307 , the controller  110  may record the audio signal using the selected microphone. In operation  309 , the PCM file creating unit  117  and the speaker position detecting unit may receive the audio signal, which has been converted into the digital signals, from the A/D converter  410 . The coder  121  of the controller  110  may encode the angle information, which is received from the speaker position detecting unit  111 , the PCM file containing the audio signal. In addition, the coder  121  of the controller  110  may also encode time information into the PCM file. The time information may include a period of time for recording the audio signal, or the start time and the end time of the recording. The coder  121  of the controller  110  may transfer the compressed audio file to the memory  160  to store the same therein. 
       FIG. 5  is a diagram of an example of a stored audio signal, according to various embodiments of the present disclosure. 
       FIG. 5  shows the file recorded as a result of executing the process of  FIG. 3 , and the horizontal axis in  FIG. 5  denotes time in which the unit may be a second. In addition, the vertical axis thereof denotes the magnitude of the audio signal in which the unit may be a decibel (dB).  FIG. 5  shows an example in which the audio signals corresponding to several angles are stored as a single file. It shows that the audio signals, and the angles, at which the audio signals are received, are stored together. In addition, it shows that the recording time of each audio signal is stored as well. The recording time may be expressed as the length of the section for the audio signal of each speaker in the file. 
     Referring to the recorded file, the audio signal A ( 510   a ) occurs at an angle of 0° ( 520   a ). The audio signal B ( 510   b ) occurs at an angle of 90° ( 520   b ). The audio signal C ( 510   c ) occurs at an angle of 180° ( 520   c ). The audio signal D ( 510   d ) occurs at an angle of 270° ( 520   d ). Comparing the section of the audio signal A with the section of the audio signal B, the section of the audio signal A ( 510   a ) is shorter than the section of the audio signal B ( 510   b ). This means that the recording time for the audio signal A ( 510   a ) is shorter than the recording time of the audio signal B ( 510   b ). 
       FIG. 6  is a diagram of an example of a system for rendering audio, according to various embodiments of the present disclosure. 
     Referring to  FIG. 6 , the controller  110  may receive the compressed and stored audio file from the memory  160 . The controller  110  may transfer the compressed audio file to the decoder  123 . In addition, the controller  110  may transfer the angle information corresponding to the compressed audio file to the user angle selecting unit  127 . The user angle selecting unit  127  may transfer the angle information to the touch screen  150 . The touch screen  150  may display all angles identified by the angle information to allow the user to select at least one thereof. The touch screen  150  may transfer the angle selected by the user to the user angle selecting unit  127 . The user angle selecting unit  127  may transfer the angle selected by the user to the PCM file creating unit  117 . The PCM file creating unit  117  may transform only the audio signal corresponding to the selected angle into a PCM file, and may transfer the same to the D/A converter. 
     The D/A converter  610  may convert the PCM file into an analog signal and feed the analog signal to the speaker  140 . The D/A converter  610  may transfer the converted audio signal to the speaker  140 , and the speaker  140  may output the audio signal. 
       FIG. 7  is a diagram illustrating an example of a rendered audio signal, according to various embodiments of the present disclosure. 
       FIG. 7  shows the reproduced audio signal, and the horizontal axis denotes the time in which the unit may be a second. In addition, the vertical axis denotes the magnitude of the audio signal in which the unit may be a decibel (dB). When the user wishes to listen to only the audio signal at an angle of 90° ( 520   b ), the audio signal  510   b  corresponding to the angle of 90° among all of the audio signals is reproduced. That is, the audio signals corresponding to the angles rather than 90° may not be reproduced. If the controller  110  recognizes the user&#39;s selection for the audio signal of 180°, the controller  110  may reproduce only the audio signal corresponding to the angle of 180° among all of the files. 
       FIG. 8  is a flowchart of an example of a process, according to various embodiments of the present disclosure.  FIG. 9  is a diagram of an example of a system implementing the process of  FIG. 8 , according to various embodiments of the present disclosure. 
     The operation of  FIG. 8  will be described in association with the signal flow of  FIG. 9 . In operation  801 , the controller  110  may perform the audio recording. The controller  110  may recognize a user&#39;s request to begin the audio recording. As shown in  FIG. 9 , three microphones may be used by the controller  110  to receive audio signals. Three A/D converters  910  may convert the audio signals received from the plurality of microphones into digital files. The three A/D converters  910  may transfer the audio signals, which have been converted into the digital files, to the controller  110 . 
     In operation  803 , the controller  110  may detect the position of the speaker. For example, the controller  110  may recognize the angle corresponding to a received audio signal. As shown in  FIG. 9 , the audio signals received by the microphone are converted into the digital signals through the A/D converters  910  to be then transferred to the speaker position detecting unit  111 . The speaker position detecting unit  111  may recognize the angles corresponding to the received audio signals, and may transfer information corresponding to the angles to the beamformer  113 . 
     In operation  805 , the beamformer  113  of the controller  110  may form a beam at the detected angle of the speaker. In instances in which several audio signals are received at different angles through the microphones, the beamformer  113  may form a beam at an angle of the audio signal that has the highest energy level. In operation  807 , the controller  110  may store the audio signal recorded by forming the beam, and angle information and time information corresponding thereto. 
     In operation  809 , the controller  110  may determine whether or not the position of the speaker has changed. The speaker position detecting unit  111  may recognize the angle of a received audio signal to thereby determine that the position of the speaker has changed. If the speaker position detecting unit  111  of the controller  110  determines that the angle of the received audio signal, i.e., the angle of the speaker, is changed, the controller may return to operation  803 . If the speaker position detecting unit  111  of the controller  110  determines that the angle of the speaker is not changed, the controller may return to operation  805 . 
     As shown in  FIG. 9 , the beamformer  113  of the controller  110  may transfer the audio signal, which is obtained by implementing the beam, to the PCM file creating unit  117 . The PCM file creating unit  117  of the controller  110  may create the audio signal received from the beamformer  113  as a PCM file to transfer the same to the coder  121 . In operation  809 , the coder  121  may compress the PCM file and the angle information received from the speaker position detecting unit  111  to create an audio file. In addition, the coder  121  of the controller  110  may compress the time information of the received audio signal in the audio file as well. The coder  121  may store the compressed audio file in the memory  160 . 
       FIG. 10  is a diagram of an example of a stored audio signal, according to various embodiments of the present disclosure.  FIG. 10  shows the file recorded through the operation of  FIG. 8 , and the horizontal axis thereof denotes the time in which the unit may be a second. In addition, the vertical axis thereof denotes the magnitude of the audio signal in which the unit may be a decibel (dB).  FIG. 5  shows an example in which that the audio signals corresponding to several angles are stored as a single file. In this example, the audio signals, which are received through the beamforming, and the angles, at which the audio signals are received, are stored together. In addition, the recording time of each audio signal may be stored, in the file as well. The recording time may be expressed as the length of the section for the audio signal of each speaker in the file. 
     Referring to the recorded file, the audio signal A ( 1010   a ) occurs at an angle of 0° ( 1020   a ). The audio signal B ( 1010   b ) occurs at an angle of 90° ( 1020   b ). The audio signal C ( 1010   c ) occurs at an angle of 180° ( 1020   c ). The audio signal D ( 1010   d ) occurs at an angle of 270° ( 1020   d ). Comparing the section of the audio signal A ( 1010   a ) with the section of the audio signal B ( 1010   b ), the section of the audio signal A ( 1010   a ) is shorter than the section of the audio signal B ( 1010   b ). This means that the recording time for the audio signal A ( 1010   a ) is shorter than the recording time of the audio signal B ( 1010   b ). 
       FIG. 11  is a diagram of a system for rendering recorded audio signals, according to various embodiments of the present disclosure. 
     Referring to  FIG. 11 , the user angle selecting unit  127  of the controller  110  may receive angle information corresponding to each audio signal from the memory  160 . The decoder  123  of the controller  110  may receive the compressed audio file from the memory  160 , and may decompress the same. The PCM file creating unit  117  of the controller  110  may receive the audio signal from the decoder  123 , and may transform the same into a PCM file. The audio signal transformed by the PCM file creating unit  117  may be transferred to the D/A converter  1110  so that the angle information is received from the user angle selecting unit  127  and only the audio signal corresponding to the angle is to be reproduced. 
     The D/A converter  1110  may convert the PCM file of a digital signal into an analog signal and feed the analog signal to the speaker  140 . The D/A converter  1110  may transfer the converted audio signal to the speaker  140 , and the speaker  140  may output the audio signal. 
       FIG. 12  is a flowchart of an example of a process, according to various embodiments of the present disclosure.  FIG. 13  is a diagram of an example of a system for implementing the process of  FIG. 12 , according to various embodiments of the present disclosure. 
     The operation of  FIG. 12  will be described in association with the signal flow of  FIG. 13 . In operation  1201 , the controller  110  may begin recording audio. For example, the controller  110  may recognize a user&#39;s request to begin the audio recording. As shown in  FIG. 13 , three microphones are used by the controller  110  to receive the audio signals. A plurality of A/D converters  1310  may convert the audio signals received from three microphones into digital files. Three A/D converters  1310  may transfer the audio signals, which have been converted into the digital files, to the controller  110 . 
     In operation  1203 , the controller  110  may detect the positions of a plurality of speakers. That is, when a plurality of audio signals is received, the controller  110  may recognize the angles corresponding to the audio signals. As shown in  FIG. 13 , the audio signals received by the three microphones are converted into digital signals by the A/D converter  1310  to be then transferred to the speaker position detecting unit  111 . The speaker position detecting unit  111  may recognize the angles corresponding to the received audio signals, and may transfer an indication of each angle to the beamformers  113   a  to  113   c.    
     In operation  1205 , the beamformers  113   a  to  113   c  of the controller  110  may form beams at each all of the detected angles, respectively. In addition, the beamformers  113   a  to  113   c  of the controller  110  may form the beams only at angles of the audio signals that have greater energies than a predetermined value. As shown in  FIG. 13 , the beamformers  113   a  to  113   c  of the controller  110  may transfer the audio signals, which are obtained by implementing the beams, to the PCM file creating units  117   a  to  117   c . The PCM file creating units  117   a  to  117   c  of the controller  110  may transform the audio signals received from the beamformers  113   a  to  113   c  into the PCM files to transfer the same to the coder  121 . In operation  1207 , the coder  121  may create audio files by associating the PCM files with a plurality of pieces of the angle information received from the speaker position detecting unit  111  to thereby compress the same. In addition, the coder  121  of the controller  110  may compress the time information of the received audio signals in the audio file as well. The coder  121  may store the compressed audio files in the memory  160 . 
       FIG. 14  is a diagram of a stored audio signal, according to various embodiments of the present disclosure. 
       FIG. 14  shows the file recorded through the operation of  FIG. 12 , and the horizontal axis thereof denotes the time in which the unit may be a second. In addition, the vertical axis thereof denotes the magnitude of the audio signal, in which the unit may be a decibel (dB).  FIG. 14  shows an example in which the audio signals corresponding to the angles are stored as respective files. In addition, it is assumed that the audio signals of the files are recorded in an order of time in  FIG. 14 . In the example  FIG. 14 , the audio signals received through the beamforming, and the angles, at which the audio signals are received, may be stored together. In addition, it shows that the recording time of each audio signal is stored as well. The recording time may be expressed as the length of the section for the audio signal of each speaker in the file. 
     Referring to the recorded file, the audio signal A ( 1410   a ) stored in File  1  occurs at an angle of 0° ( 1420   a ). The audio signal B ( 1410   b ) stored in File  2  occurs at an angle of 90° ( 1420   b ). The audio signal C ( 1410   c ) stored in File  3  occurs at an angle of 180° ( 1420   c ). The audio signal D ( 1410   d ) stored in File  4  occurs at an angle of 270° ( 1420   d ). 
     In addition, although it is not shown in the drawing, the respective representations of all audio signals may be encapsulated in the same file. For example, when another audio signal occurs at the angle of 0° ( 1420   a ), another audio signal  1410   a  may be stored in File  1 . If another audio signal additionally occurs after the audio signal  1410   d  is stored, the additionally created audio signal may be stored after the audio signal  1410   d  in File  1 . In addition, if another audio signal additionally occurs in the middle of storing the audio signal  1410   c , the additionally created audio signal may be stored at the same time as the audio signal  1410   c  of the speaker C ( 1401   c ) in File  1 . 
       FIG. 15  is a diagram of an example of a system for rendering a stored audio signal, according to various embodiments of the present disclosure. 
     Referring to  FIG. 15 , the user angle selecting unit  127  of the controller  110  may receive the position information, i.e., the angle information corresponding to the speaker from the memory  160 . The user angle selecting unit  127  may transfer the received angle information to the touch screen  150 , and the touch screen  150  may display the angles corresponding to the received angle information. The user angle selecting unit  127  may recognize the angle selected by the user on the touch screen  150 . The user angle selecting unit  127  may transfer the selected angle to the decoder  123 , and the decoder  123  may receive only the file corresponding to the selected angle from the memory  160 . The decoder  123  may decompress the received file, and may perform the buffer and mixing process  1570  with respect to the file corresponding to the angle selected by the user angle selecting unit  127 . The controller  110  may transfer the processed file to the PCM file creating unit  117 , and the PCM file creating unit  117  may transform the transferred file to a PCM file. The file created by the PCM file creating unit  117  may be transferred to the D/A converter  1510 . The D/A converter  1510  may convert the PCM file of the digital signal into an analog signal and feed the analog signal to the speaker  140 . The D/A converter  1510  may transfer the converted audio signal to the speaker  140 , and the speaker  140  may output the audio signal. 
       FIG. 16  is a diagram illustrating an example a process for recording audio, according to various embodiments of the present disclosure. Three microphones may be arranged in different directions from each other. One or more beams may be formed through a combination of three microphones. 
     As shown in the drawing, three microphones  1641 ,  1642 , and  1643  are disposed in different directions from each other, and four beams  1611 ,  1612 ,  1613 , and  1614  may be formed through a combination of the three microphones  1641 ,  1642 , and  1643 . Each of the beams  1611 ,  1612 ,  1613 , and  1614  may receive the audio signal only at its formed angle. The received audio signals may be stored together with angle information corresponding thereto. 
       FIG. 17  is a diagram of an example of a user interface for rendering audio, according to various embodiments of the present disclosure. 
     Referring to  FIG. 17 , the controller  110  may display a UI on the touch screen  150 , which allows the user to reproduce an audio signal that is associated with a desired direction. In an embodiment, the UI may include identifiers, which indicate the locations of the speakers relative to a microphone array used to record the sound produced by the speakers. The identifiers may be displayed on the circle to correspond to the angles of the speakers. As shown in the drawing, an identifier A ( 1701   a ), an identifier B ( 1701   b ), an identifier C ( 1701   c ), and an identifier D ( 1701   d ) are displayed at the positions corresponding to 0°, 90°, 180°, and 270°, which may be approximate locations of the speakers relative to the microphone array. 
     If the user selects at least one of the identifiers, the controller  110  may reproduce the audio file associated with the angle corresponding to the identifier. In addition, if the user selects the all-play button  1750 , the controller  110  may reproduce all of the audio files through the speaker. All of the audio files may be the files that include the audio signals at all angles. 
       FIG. 18  is a diagram of an example of a user interface for rendering audio, according to various embodiments of the present disclosure. 
     Referring to  FIG. 18 , the controller  110  may display a list that allows the user to select an audio signal that is associated with a desired direction. The list may include an identifier that indicates the speaker, a play button  1850 , a stop button  1860 , and a recording time  1870 . If the user selects one of the identifiers  1801   a  to  1801   d , the controller  110  may reproduce the stored audio file corresponding to the selected identifier through the speaker  140 . For example, when the user selects the play button  1850  in order to listen to the audio signal of the identifier A ( 1801   a ), the controller  110  may reproduce the stored audio file associated with the identifier  1801   a  for 3 min 40 sec. 
     In addition, when one of the identifiers is selected by the user, the controller  110  may provide section information corresponding to the selected identifier. The section information may be the information indicating the start time and the end time of the recorded audio signal of the speaker corresponding to the selected identifier among the entire recording time. The controller  110  may express the section information as images or numbers. 
     For example, when the user selects the identifier A ( 1801   a ), the controller  110  may provide the section information corresponding to the selected identifier A ( 1801   a ). The section information of the identifier A ( 1801   a ) may be the information stating that the audio signal is recorded from the time of 3 min to the time of 6 min 40 sec of the whole recording time of 27 min 35 sec. The controller  110  may provide the section information when the user selects the identifier A ( 1801   a ), or may display the section information in the list or in the reproduced image when the recording time is selected or while the audio file is reproduced. 
       FIG. 19  is a diagram of an example of a user interface for rendering audio, according to various embodiments of the present disclosure. 
     The controller  110  may identify the speakers of the recorded audio signals as well as the audio signals according to the angles. To this end, the controller  110  may pre-store speaker recognition information using a sound-shot function before performing the audio recording. The speaker recognition information may include the waves of the audio signals and photos of the speakers. The sound-shot function refers to the function of storing the audio signal recorded when taking a photo, together with the photo. 
     For example, if the user photographs the face of the speaker A ( 1900   a ) and records the audio signal  1910   a  of the speaker using the sound-shot function, the controller  110  may map the photo with the audio signal to thereby store the same as a single audio file  1901   a  in the memory  160 . As shown in  FIG. 19 , the photos of the speaker A ( 1900   a ), the speaker B ( 1900   b ), the speaker C ( 1900   c ), and the speaker D ( 1900   d ) may be stored together with the audio signal wave  1910   a  of the speaker A ( 1900   a ), the audio signal wave  1910   b  of the speaker B ( 1900   b ), the audio signal wave  1910   c  of the speaker C ( 1900   c ), and the audio signal wave  1910   d  of the speaker D ( 1900   d ) as files  1901   a  to  1901   d , respectively. The audio signal waves may be distinct from each other depending on the features of the human voice, so the audio signal wave may be used to identify the speakers. 
     In another embodiment, in order to recognize the speakers, the user may pre-store the voices of the speakers as the speaker recognition information before the recording of the audio signals. According to this, the controller  110  may record the voices of the speakers to be stored in the memory  160 , and may use the same for the comparison later. Additionally or alternatively, when storing the voices of the speakers, the user may also store the names of the speakers, and/or other information that can be used to indicate the speakers&#39; identities. 
     In another embodiment, during a phone call with those who are stored in the contact information, the controller  110  may store the voices of the speakers in the memory  160  to use the same as the speaker recognition information. 
       FIG. 20  is a diagram of an example of a process for recording audio, according to various embodiments of the present disclosure. 
     As mentioned in  FIG. 19 , the controller  110  may take photos of the speakers, and may pre-store the photos and the audio signals in the memory  160  using the sound-shot function, in order to identify the speaker of the recorded audio signal according to the angles. Referring to  FIG. 20 , the controller  110  may compare the waves of the audio signals stored at the angles with the audio signal waves of the sound-shot files stored in the memory  160 . If the controller  110  finds the sound-shot file that has an audio signal wave that matches the wave of the stored audio signal at each angle, the controller  110  may map the photo of the sound-shot file with the audio signal stored at each angle to thereby store the same. For example, as shown in  FIG. 20 , the speaker A ( 2001   a ), the speaker B ( 2001   b ), the speaker C ( 2001   c ), and the speaker D ( 2001   d ) may form the beams  2011  to  2014  to receive the audio signals of the speakers, respectively. The memory  160  may have the photos and the audio signals of the speakers  2001   a  to  2001   d . The controller  110  may compare the received audio signal waves of the speakers with the audio signal waves stored in the memory  160  to thereby map the same to match each other to be then stored. 
     In another embodiment, the controller  110  may compare the received audio signal waves of the speakers with the audio signal waves that have been pre-recorded and pre-stored for the comparison. The controller  110  may compare the received audio signal waves of the speakers with the audio signal waves stored in the memory  160  to determine the respective identities of the speakers. 
     In another embodiment, the controller  110  may compare the received audio signal waves of the speakers with the audio signal waves of the users who are represented in the contact information. The controller  110  may compare the received audio signal waves of the speakers with the audio signal waves stored in the memory  160  to determine the identities of the speakers. 
     Referring to the files recorded according to the various embodiments above, the audio signal A ( 2010   a ) stored in File  1  occurs at an angle of 0° ( 2020   a ) by the speaker A ( 2001   a ). The audio signal B ( 2010   b ) stored in File  2  occurs at an angle of 90° ( 2020   b ) by the speaker B ( 2001   b ). The audio signal C ( 2010   c ) stored in File  3  occurs at an angle of 180° ( 2020   c ) by the speaker C ( 2001   c ). The audio signal D ( 2010   d ) stored in File  4  occurs at an angle of 270° ( 2020   d ) by the speaker D ( 2001   d ). 
       FIG. 21  is a diagram of an example of a user interface for rendering audio, according to various embodiments of the present disclosure. 
     As mentioned in  FIG. 20 , the audio files may be stored according to the speaker through the speaker recognition. The controller  110  may create documents with respect to the files stored according to the speakers, using a speech-to-text (STT) function. 
     As shown in  FIG. 21 , the controller  110  may create the minutes  2100  as one of the documents. The minutes  2100  may include identifiers  2101  or photos of the speakers for identifying the speakers, STT-transformed text  2103 , the recording time of the audio file  2105 , and play buttons  2107  for reproducing the audio file. For example, the controller  110  may transform the audio file of the speaker A ( 2101   a ), which is recorded first, into the text, and may record the same in the minutes  2100  ordered by time. The controller  110  may include the play button  2107  for reproducing the audio file corresponding to the recording time  2105  of “00:00:00˜00:00:34” in the minutes  2100 . 
       FIGS. 1-21  are provided as an example only. At least some of the steps discussed with respect to these figures can be performed concurrently, performed in a different order, and/or altogether omitted. It will be understood that the provision of the examples described herein, as well as clauses phrased as “such as,” “e.g.”, “including”, “in some aspects,” “in some implementations,” and the like should not be interpreted as limiting the claimed subject matter to the specific examples. 
     The above-described aspects of the present disclosure can be implemented in hardware, firmware or via the execution of software or computer code that can be stored in a recording medium such as a CD-ROM, a Digital Versatile Disc (DVD), a magnetic tape, a RAM, a floppy disk, a hard disk, or a magneto-optical disk or computer code downloaded over a network originally stored on a remote recording medium or a non-transitory machine-readable medium and to be stored on a local recording medium, so that the methods described herein can be rendered via such software that is stored on the recording medium using a general purpose computer, or a special processor or in programmable or dedicated hardware, such as an ASIC or FPGA. As would be understood in the art, the computer, the processor, microprocessor controller or the programmable hardware include memory components, e.g., RAM, ROM, Flash, etc. that may store or receive software or computer code that when accessed and executed by the computer, processor or hardware implement the processing methods described herein. In addition, it would be recognized that when a general purpose computer accesses code for implementing the processing shown herein, the execution of the code transforms the general purpose computer into a special purpose computer for executing the processing shown herein. Any of the functions and steps provided in the Figures may be implemented in hardware, software or a combination of both and may be performed in whole or in part within the programmed instructions of a computer. No claim element herein is to be construed under the provisions of 35 U.S.C. 112, sixth paragraph, unless the element is expressly recited using the phrase “means for”. 
     While the present disclosure has been particularly shown and described with reference to the examples provided therein, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims.