JP2010050571A - Sound pickup device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of picking up sound while more reducing noise influence than heretofore in a sound pickup device for picking up voice of a speaker. <P>SOLUTION: A microphone 16 can pick up sound by switching the direction of the directivity of picking up sound to at least two directions. The sound picked up by the microphone 16 is outputted as a sound signal to an A/D converting part 18, converted into digital data by the A/D converting part 18 and stored in a memory 13 time sequentially. A tilt sensor 21 detects the tilt of the sound pickup device 1 and outputs a signal showing the detection result. A CPU 11 controls a directivity setting part 17 to switch the direction of the directivity of the microphone 16 in accordance with the tilt of a device body detected by the tilt sensor 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sound collection device.

2. Description of the Related Art Conventionally, portable sound pickup devices that record voice have been developed (see, for example, Patent Document 1). Also, a technique for setting the directivity of sound collection in the direction of a speaker has been proposed in order to reduce the influence of noise when recording voice (see Patent Document 2).
Japanese Patent Laid-Open No. 11-31000 Japanese Patent Laid-Open No. 05-207117

As described above, in the sound collection device, depending on the position of the speaker, the voice of the speaker may not be clearly recorded due to the influence of noise. In particular, in a portable sound pickup device held by a user such as a so-called IC recorder, the user may change the direction of the sound pickup device depending on the situation. Since the relationship is not constant, the direction of the speaker and the direction of directivity of sound collection may shift, and the influence of noise may increase.
The present invention has been made in view of the above-described circumstances, and provides a technology capable of collecting sound while reducing the influence of noise in a sound collecting device that picks up the voice of a speaker as compared with the prior art. For the purpose.

  In order to solve the above-described problems, the present invention provides sound collection means that can collect sound by switching the direction of sound collection directivity to at least two directions, detection means that detects an inclination of a device body in a predetermined direction, and the detection And a control unit that switches a direction of directivity of the sound collection unit according to the inclination of the apparatus main body detected by the unit.

  In a preferred aspect of the present invention, the apparatus includes a comparison unit that compares the inclination detected by the detection unit with a sound collection angle that is determined in advance with respect to the direction of gravity, and the control unit includes a comparison result obtained by the comparison unit. In response, the directionality of the sound collection means may be switched so that the directionality of the sound collection means with respect to the direction of gravity is close to the predetermined sound collection angle.

  Further, in a further preferred aspect of the present invention, a voice data storage means for storing voice data representing the voice picked up by the sound pickup means, and a correspondence relationship between the inclination range and the voice data storage mode are stored. A correspondence relationship storage means, a selection means for selecting a storage mode corresponding to the inclination detected by the detection means with reference to the correspondence relationship storage means, and a sound representing the sound collected by the sound collection means And storage control means for storing data in time series in the audio data storage means in the storage mode selected by the selection means.

  Further, in a further preferred aspect of the present invention, the correspondence relationship storage means stores a correspondence relationship between the slope range and an identifier for classifying a speaker, and the selection means refers to the correspondence relationship storage means. The identifier corresponding to the inclination detected by the detecting means is selected, and the storage control means assigns the identifier selected by the selecting means to the sound data representing the sound collected by the sound collecting means. Then, the audio data storage means may store the data in time series.

  Moreover, in another preferable aspect of the present invention, the sound data storage means has a plurality of storage areas, the correspondence relation storage means stores a correspondence relation between the inclination range and the storage area, and The selecting means refers to the correspondence relationship storing means, selects a storage area corresponding to the inclination detected by the detecting means, and the storage control means is a sound representing the sound collected by the sound collecting means. Data may be stored in time series in the storage area selected by the selection means.

  Further, in a further preferred aspect of the present invention, the apparatus further comprises a determination unit that determines whether or not the inclination of the apparatus main body has been changed by a predetermined threshold or more according to the inclination detected by the detection unit. The means may switch the identifier to be selected at a timing when the determination means determines that the inclination of the apparatus main body has been changed by the threshold value or more.

  ADVANTAGE OF THE INVENTION According to this invention, in the sound collection apparatus which collects a speaker's audio | voice, it can collect sound, reducing the influence of noise compared with the past.

Embodiments of the present invention will be described below with reference to the drawings.
<A: Configuration>
FIG. 1 is a diagram showing a configuration of a portable sound collecting device 1 according to an embodiment of the present invention, and FIG. 2 is a perspective view showing an appearance of the sound collecting device 1. The portable sound pickup device 1 is a portable sound pickup device held by an operator. In the figure, the CPU 11 reads out and executes a computer program stored in the ROM 12 or the memory 13 to control each part of the portable sound pickup device 1 via the bus BUS. The memory 13 is a storage means such as an EEPROM. The RAM 14 is used as a work area when the CPU 11 executes a computer program.

  The input unit 15 includes various buttons (not shown) such as a recording start button for starting recording and a recording end button for ending recording, and outputs a signal corresponding to an operation by the operator. The microphones 16a, 16b, and 16c collect sounds input to the respective microphones, and output audio signals (analog signals) representing the collected sounds. As shown in FIG. 2, the microphones 16 a, 16 b, and 16 c are provided on the front surface of the sound collection device 1. In the following description, for convenience of description, when it is not necessary to distinguish the microphones 16a, 16b, and 16c, they will be referred to as “microphones 16”. The arrangement of the microphones 16 is not limited to that illustrated in FIG. 2, and any arrangement may be used as long as sound collection is possible by switching the direction of sound collection directivity to at least two directions. In addition, in FIG. 2, the configuration in the case where three microphones are provided has been described. However, the number of microphones is not limited to three, and may be more or less. In short, the direction of sound collection directivity is determined. It is sufficient that sound can be collected by switching to at least two directions.

  The directivity setting unit 17 sets the directivity of sound collection of the microphone 16 under the control of the CPU 11. Under the control of the directivity setting unit 17, the microphone 16 can collect sound by switching the direction of sound collection directivity in various ways. For example, sound signals collected by the microphones 16a, 16b, and 16c are subjected to delay processing in accordance with a designated direction and added and output, thereby forming a sound collection beam having strong directivity in a specific direction. The In this embodiment, the direction of arrow A in the drawing is initially set as the directivity direction of the microphone 16. The A / D converter 18 converts the audio signal (analog signal) output from the microphone 16 into digital data by A / D conversion. The D / A converter 19 converts the digital data supplied from the memory 13 into an analog signal by D / A conversion in accordance with an audio reproduction instruction and outputs the analog signal. The speaker 20 emits sound with an intensity corresponding to the analog signal supplied from the D / A converter 19.

  The inclination sensor 21 is a sensor that detects the inclination of the sound collection device 1 main body in a predetermined direction. As the tilt sensor 21, for example, a piezoresistive type or a capacitance type triaxial acceleration sensor is used. FIG. 3 is a diagram showing the content of the tilt detected by the tilt sensor 21. As shown in FIG. 3, the tilt sensor 21 detects the tilt angle θa of the sound collecting device 1 main body with respect to the direction of gravity. The inclination of the sound collecting device 1 main body detected by the inclination sensor 21 is not limited to that illustrated in FIG. 3, and what is the detection mode as long as the inclination of the sound collecting device 1 main body is detected in a predetermined direction. It may be anything.

<B: Operation>
Next, the operation of this embodiment will be described. The operator of the sound collection device 1 first performs an operation for starting recording by pressing a recording start button of the sound collection device 1 or the like. The input unit 15 outputs a signal corresponding to the content operated by the operator, and the CPU 11 starts recording by controlling each unit of the sound collection device 1 according to the signal output from the input unit 15. The sound collected by the microphone 16 is output as an audio signal to the A / D converter 18, converted into digital data (hereinafter referred to as “audio data”) by the A / D converter 18, and stored in the memory 13 in time series. Is done.

  While the sound collection device 1 is recording, the inclination sensor 21 detects the inclination of the sound collection device 1 and outputs a signal indicating the detection result. The CPU 11 switches the directivity direction of the microphone 16 by controlling the directivity setting unit 17 according to the inclination of the apparatus main body detected by the inclination sensor 21.

  Here, an example of the content of the directivity control process performed by the sound collection device 1 will be described with reference to FIG. First, the CPU 11 detects the tilt angle θa of its own device from the signal output from the tilt sensor 21. Next, the CPU 11 compares the detected inclination angle θa with a predetermined reference angle θd. This reference angle θd has a relative positional relationship between the position of the user's hand and the position of the speaker so that the sound of the speaker can be preferably collected when the user holds the sound collecting device 1. A predetermined value is preferably set accordingly. The CPU 11 switches the directivity direction of the microphone 16 by controlling the directivity setting unit 17 so that the directivity direction of the microphone 16 with respect to the direction of gravity is close to the reference angle θd according to the comparison result between the two. The directivity setting unit 17 sets the directivity of the microphone 16 in accordance with an instruction from the CPU 11. Specifically, in the example shown in FIG. 3, the CPU 11 calculates a difference Δθ between the detected inclination angle θa and the reference angle θd, and rotates the directivity direction of the microphone 16 from the initial setting direction A by Δθ. The directivity setting unit 17 is controlled. That is, the CPU 11 controls the directivity setting unit 17 according to the calculated difference Δθ so that the directionality of the microphone 16 with respect to the gravitational direction is the reference angle θd.

  FIG. 4 is a diagram illustrating an example of a specific operation of the sound collection device 1. In the example shown in FIG. 4, the user S1 uses the sound collection device 1 to record the voice of the speaker S2. In the example shown in the figure, the user S1 performs recording while tilting the sound collecting device 1 in the direction of the speaker S2. In this case, if sound is collected in the sound collection direction A that is initially set in the sound collection device 1, the direction of the speaker with respect to the sound collection device 1 and the direction A of sound collection are shifted. The speaker's voice may not be clearly recorded due to Therefore, the sound collection device 1 detects the tilt of the own device, and controls the directionality of the microphone 16 so that the directivity direction becomes a predetermined reference angle θd in consideration of the detected tilt. . By doing in this way, a speaker's voice can be recorded more clearly compared with the past. In addition, it is preferable that the reference angle predetermined for the sound collection device 1 is an angle corresponding to the relative positional relationship between the position of the user's hand of the sound collection device 1 and the position of the speaker.

  The inclination sensor 21 of the sound collection device 1 detects the inclination of the sound collection device 1 while the sound collection device 1 is recording, and sequentially outputs a signal indicating the detection result every predetermined unit time. The CPU 11 controls the directivity setting unit 17 according to the detection result and changes the directivity direction of the microphone 16 every time the inclination of the apparatus main body of the sound pickup apparatus 1 changes according to the signal output from the inclination sensor 21. Switch. By doing in this way, even if the user S1 changes the inclination of the sound collection device 1 during recording, the directivity direction according to the inclination of the sound collection device 1 can be set sequentially, and sound collection with less noise is possible. It can be performed.

  As described above, according to the present embodiment, a direction in which a directivity characteristic is controlled by mounting a plurality of microphones in a portable recording apparatus and a user operation or inclination is detected, and the directivity characteristic is provided. Control. In this way, by performing sound collection in which directivity control is performed in accordance with the inclination of the apparatus main body, better sound collection with less noise compared to the prior art becomes possible.

  For example, when conducting an interview, in order to record the conversation between the interviewer and the interviewee, the microphone of the portable recording device is directed to the interviewer or to the interviewee. Since the portable recording device is tilted by pointing the microphone, it is possible to collect sound with less noise by collecting sound with directivity controlled in accordance with the tilt.

<C: Modification>
As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above, It can implement with another various form. An example is shown below. In addition, you may combine each following aspect suitably.
(1) In the above-described embodiment, the CPU 11 performs control so as to switch the directivity of the microphone 16 in various directions. Instead, the CPU 11 switches the directivity of the microphone 16 in one of two directions. It may be. In short, the inclination sensor 21 detects the inclination of the sound collecting device 1, and the CPU 11 may be controlled to switch the directivity in at least two directions according to the detected inclination.

(2) In the above-described embodiment, a speaker may be determined based on the inclination angle of the sound collection device 1 and may be recorded separately for each speaker. Specifically, the directivity direction and the speaker (whether they are the other party) may be associated with each other so that they can be distinguished by setting a flag when recording or by recording in another area. In this case, the memory of the sound collection device 1 stores in advance the correspondence relationship between the range of the tilt angle and the storage mode of the audio data, and the CPU 11 stores the corresponding mode corresponding to the tilt angle detected by the tilt sensor 21. May be selected with reference to the correspondence stored in the memory, and audio data representing the sound collected by the microphone 16 in the selected storage mode may be stored in time series.

  In the above-described aspect, as an audio data storage aspect, for example, an identifier for identifying a speaker may be given. In this case, the correspondence relationship between the range of the inclination angle and the identifier for identifying the speaker is stored in advance in the memory of the sound collection device 1, and the CPU 11 refers to the correspondence relationship stored in the memory and refers to the inclination sensor. Alternatively, an identifier corresponding to the tilt angle detected by 21 may be selected, and the selected identifier may be assigned to the audio data and stored.

  In the above case, when the CPU 11 reproduces the recorded voice, only the voice of a specific speaker may be reproduced. In this case, for example, the CPU 11 may reproduce only the audio data to which a specific identifier is assigned. By doing in this way, it becomes possible to reproduce | regenerate audio | voice data for every speaker.

  As another example, for example, an area in the memory where audio data is stored is divided into a plurality of areas, and a correspondence relationship between the range of the inclination angle and the storage area is stored in the memory in advance. The storage area corresponding to the inclination angle detected by the inclination sensor 21 may be selected with reference to the correspondence relationship stored in the above, and the audio data may be stored in the selected storage area.

  In the above-described aspect, the CPU 11 determines whether the inclination angle of the apparatus main body has been changed by a predetermined threshold value or more using the inclination detected by the inclination sensor 21, and the inclination angle is changed by the threshold value or more. The identifier to be selected may be switched at a timing at which it is determined that it has been determined.

(3) In the above-described embodiment, the sound data representing the sound collected by the microphone 16 is stored in the internal memory 13 of the sound collection device 1, but instead of this, an external memory such as an external hard disk or the like is stored. You may make it memorize.

(4) In the above-described embodiment, the CPU 11 compares the inclination angle θa detected by the inclination sensor 21 with a predetermined reference angle θd so that the direction of directivity is close to the predetermined reference angle. However, the control mode is not limited to this. For example, the CPU 11 controls the direction of the microphone 16 so that it is equal to the detected tilt direction. In short, it is only necessary that the CPU 11 switches the direction of the directivity of the microphone in accordance with the inclination of the apparatus main body.

(5) In the above embodiment, the program executed by the CPU 11 of the sound collection device 1 is a magnetic recording medium (magnetic tape, magnetic disk, etc.), an optical recording medium (optical disk, etc.), a magneto-optical recording medium, a semiconductor memory, etc. It can be provided in a state of being recorded on a computer-readable recording medium. It is also possible to download the sound collecting device 1 via a network such as the Internet.

It is a figure which shows an example of a structure of a sound collection device. It is a perspective view which shows the external appearance of a sound collection device. It is a figure for demonstrating the inclination which an inclination sensor detects. It is a figure for demonstrating the content of operation | movement of a sound collection device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Sound collecting device, 11 ... CPU, 12 ... ROM, 13 ... Memory, 14 ... RAM, 15 ... Input part, 16 ... Microphone, 17 ... Directivity setting part, 18 ... A / D conversion part, 19 ... D / A conversion part, 20 ... speaker, 21 ... inclination sensor.

Claims (6)

Sound collection means capable of collecting sound by switching the direction of sound collection directivity to at least two directions;
Detection means for detecting the inclination of the device body in a predetermined direction;
And a control means for switching the direction of directivity of the sound collecting means in accordance with the inclination of the apparatus main body detected by the detecting means. Comparing means for comparing the inclination detected by the detecting means with a predetermined sound collection angle with respect to the direction of gravity,
The control means controls the directivity of the sound collection means so that the direction of directivity of the sound collection means with respect to the direction of gravity is close to the predetermined sound collection angle according to the comparison result by the comparison means. The sound collecting device according to claim 1, wherein the direction is switched. Voice data storage means for storing voice data representing the voice picked up by the sound pickup means;
Correspondence storage means for storing the correspondence between the range of inclination and the storage mode of the audio data;
A selection unit that selects a storage mode corresponding to the inclination detected by the detection unit with reference to the correspondence storage unit;
Storage control means for storing sound data representing the sound collected by the sound collection means in time series in the sound data storage means in the storage mode selected by the selection means. Item 3. The sound collecting device according to Item 1 or 2. The correspondence storage means stores a correspondence between the range of inclination and an identifier for classifying a speaker,
The selecting means refers to the correspondence storage means and selects an identifier corresponding to the inclination detected by the detecting means;
The storage control means assigns the identifier selected by the selection means to the sound data representing the sound collected by the sound collection means and stores the sound data in the time series in the sound data storage means. The sound collection device according to claim 3. The voice data storage means has a plurality of storage areas,
The correspondence storage means stores a correspondence between the inclination range and the storage area,
The selection means refers to the correspondence storage means, selects a storage area corresponding to the inclination detected by the detection means,
The sound storage unit according to claim 3, wherein the storage control unit stores sound data representing the sound collected by the sound collection unit in a time series in the storage area selected by the selection unit. apparatus. Determining means for determining whether or not the inclination of the apparatus main body has been changed by a predetermined threshold or more according to the inclination detected by the detecting means;
The sound collection device according to claim 4, wherein the selection unit switches an identifier to be selected at a timing when the determination unit determines that the inclination of the device main body has been changed by the threshold value or more.

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