JP2001056700A - Voice recording/reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely execute the voice information retrieval by controlling an information recording state onto a recording medium based on an output of a detective means detecting a voice arrival direction. SOLUTION: A direction estimate part 15 estimates a voice arrival angle θbased on the voice information from a microphone 11. A system control part 3 judges that an utterer is changed when the absolute value of the estimated voice arrival angle θ is larger than a prescribed threshold, and records a present address value in an index information area 4a on a voice memory 4. Further, when the absolute value of the arrival angle θ isn't larger than the prescribed threshold the system control part 3 controls a voice gathering control part 16, and performs voice gathering processing collecting output voice signals of respective microphones 11 to the voice of 1 channel based on the voice arrival angle θ. In such a manner, the voice gathering processed voice data are coding processed properly in a digital signal processing part 2, and the system control part 3 records the coded data in a voice data area 4b on the voice memory 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio recording and reproducing apparatus, and more particularly to an audio recording and reproducing apparatus having a search function based on recorded audio information.

[0002]

2. Description of the Related Art Heretofore, when creating the minutes of a meeting or the like, a voice or the like of the meeting is recorded in advance, and the minutes are created later based on the recorded voice information. In addition, an audio recording / reproducing apparatus having an audio information search function has been proposed to cope with a long-time conference recording. As such a search function, for example, there is known a technique in which predetermined segmentation or index information is added to recorded sound (recorded) to use for later search.

In such a segmentation and index information adding technique, ideally for each sentence, or in a case where a plurality of speakers appear in a conference, in order to improve searchability, each speaker is used. It is desirable that segmentation and index information be automatically added to the data.

Conventionally, as a technique for providing automatic index information, a technique of starting a recording operation and adding index information when a voice is detected using a voice-activated recording technique has been widely known, and this function is provided. Audio recording and playback devices are also widely known.

Further, in a conventional audio recording apparatus using an analog tape or digital audio tape, a desired information is searched in order by searching for an index mark recorded, or a search is made for silence to search for silence. A device capable of performing the following is known.

On the other hand, in recent years, an audio signal obtained by a microphone or the like is converted into a digital signal and recorded in, for example, a semiconductor memory. At the time of reproduction, the audio signal is read from the semiconductor memory and converted into an analog signal. A digital information recording / reproducing apparatus called a so-called digital recorder which outputs sound as a sound by a speaker or the like has been developed. Also, JP-A-63-259700
Japanese Patent Application Laid-Open Publication No. HEI 10-125555 discloses a digital information recording / reproducing apparatus as described above.

In general, in a storage / playback apparatus such as the above-described digital information recording / playback apparatus, an IC memory card is provided with an audio data storage area and a header information storage area, and header information data for search is recorded in the header information area. Japanese Patent Laying-Open No. 5-28790 discloses a digital information recording / reproducing apparatus for recording header information data for search in this header information area.

[0008]

However, in the voice recording / reproducing apparatus using the above-described voice-activated recording technique, the timing of the start of the recording does not always indicate the beginning of a sentence or a change of speaker. That is, there is a problem that the index information is not added to a natural position in the voice.

The present invention has been made in view of the above problems, and has as its object to provide an audio recording / reproducing apparatus for more reliably searching audio information.

[0010]

According to a first aspect of the present invention, there is provided an audio recording / reproducing apparatus which records and reproduces audio using a recording medium. And control means for controlling the state of recording information on the recording medium based on the output of the detecting means.

[0011] In order to achieve the above object, a second aspect of the present invention is provided.
An audio recording / reproducing apparatus for recording and reproducing audio using a recording medium, comprising: an audio input unit having a plurality of microphones; and estimating an arrival direction of the audio based on an output of the audio input unit. Direction estimating means, and together with the audio information obtained by the audio input means, recording means for recording position information indicating a desired position of the audio as index information on the recording medium, the recording means, When the arrival direction of the sound estimated by the direction estimating means changes by a predetermined value or more, the index information is recorded.

In order to achieve the above object, a third aspect of the present invention is provided.
An audio recording / reproducing apparatus for recording and reproducing audio using a recording medium, comprising: an audio input unit having a plurality of microphones; and estimating an arrival direction of the audio based on an output of the audio input unit. Direction estimating means, and recording means for recording the audio information obtained by the audio input means on the recording medium by performing a predetermined division, wherein the recording means is estimated by the direction estimating means. When the arrival direction of the voice changes by a predetermined value or more, the classification is performed and voice information is recorded.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block circuit diagram showing a configuration of an audio recording / reproducing apparatus according to an embodiment of the present invention.

As shown in FIG. 1, the audio recording / reproducing apparatus of the present invention includes a microphone array 1 as audio input means for converting audio into an electric signal. The microphone array 1 is a conventionally known technique for performing signal processing for emphasizing a predetermined audio signal among a plurality of audio signals, and its configuration and the like are described in detail in JP-A-11-18187. The present applicant pays attention to the characteristics of the microphone array, and invents and provides an audio recording / reproducing apparatus that functions as another application using the microphone array. Hereinafter, the configuration of the microphone array 1 in the present embodiment will be described.

Microphone array 1 in the present embodiment
Has a plurality of microphones 11 (sound collecting means), and the audio output from these microphones 11 is amplified by a microphone amplifier (AMP) 12 connected to each of them. The outputs of the microphone amplifiers 12 are respectively supplied to A through a low-pass filter (LPF) 13.
The analog audio signal amplified by the microphone amplifier 12 is input to an A / D converter (A / D) 14. Is cut and the A / D
It is input to the converter 14.

An output terminal of each of the A / D converters 14 is connected to a direction estimating unit 15 for estimating a direction of a sound source (a direction of arrival of sound) based on sound information from the plurality of microphones 11. . The output of the direction estimating unit 15 is sent to the system control unit 3 described later on the one hand, and is sent to the sound collection control unit 16 on the other hand. The sound collection control unit 16 converts the sound input from each of the microphones 11 into one based on the direction information of the sound source estimated by the direction estimation unit 15.
The sound pickup control for integrating the sound signals of the channels, that is, the directivity adjustment is performed.

The direction estimating section 15 is a technique known per se, but has a function of estimating the direction of arrival of voice based on the time difference between the sound waves arriving at each microphone 11.

The direction estimating section 15 serves as a direction estimating means for estimating the direction of arrival of voice based on the output of the microphone array 1. The microphone array 1 is provided with a system control section 3 which will be described later. Under control, it functions as detection means for detecting the direction of arrival of voice or the switching or change of the speaker (speaker).

The output from the sound pickup control unit 16, that is, the output terminal of the microphone array 1 is connected to the digital signal processing unit 2. The digital signal processing unit 2 is constituted by a so-called DSP. During recording, the digital audio signal from the microphone array 1 is compression-converted (encoded) under the control of the system control unit 3 into data of a certain format.
Then, the encoded data is transmitted to the system control unit 3.
At this time, the audio data is divided into units of a frame having a predetermined data length, and audio processing is performed using the frame as a unit. On the other hand, at the time of reproduction, a process of expanding and converting (decoding) the data from the system control unit 3 under the control of the system control unit 3 is performed, and the decoded digital signal is input to the D / A converter 5.

The D / A converter 5 is connected to the digital signal processing unit 2. The audio signal converted into an analog signal by the D / A converter 5 cuts an unnecessary frequency band to reduce quantization noise. A power amplifier (AMP) that amplifies the audio signal and drives a speaker through a low-pass filter 6 that reduces the noise
7 is input. The audio signal amplified by the power amplifier 7 is generated by a speaker 8 which converts the audio signal into sound and emits the sound.

The system control section 3 is constituted by a microprocessor (CPU) and serves as control means for controlling the operation of each section of the audio recording / reproducing apparatus. Comparing means for comparing a value with a value, a control means for changing a recording method of information on a recording medium based on an output of the direction estimating unit 15, and a desired position of sound together with sound information obtained by the microphone array 1. It serves as a component of recording means for generating the indicated position information as index information and recording the index information in a predetermined area of the recording medium.

Further, the system control unit 3 together with the microphone array 1 (particularly based on the information from the direction estimating unit 15) detects the direction of arrival of the voice or the switching or change of the speaker (speaker). Functions as a component of.

An audio memory 4 for recording predetermined audio information and the like can be connected to the system control unit 3. The audio memory 4 is a recording medium which is detachable from the audio recording and reproducing apparatus and has an audio data area 4b in which predetermined audio data is recorded and an index information area 4a in which index information relating to the audio data is recorded. is there.

FIG. 2 is an explanatory diagram showing a recording area of the audio memory 4. As shown in FIG. As shown in the figure, the recording area of the audio memory 4 includes an index information area 4a and an audio data area 4a.
b. In the present embodiment, a user ID, a recording start date and time, a recording end date and time, and an index mark (I-ku) address (1 to 15 in this embodiment) are recorded in the index information area 4a. It has become.

Further, an address control circuit (not shown) is connected to the system control unit 3, and an appropriate address signal is supplied to the address control circuit in accordance with the operation of the operation input unit 9, and the digital signal processing unit In addition to the audio data supplied from the digital signal processing unit 2, the recording date and time, index information, and the like are recorded in the audio memory 4 based on a predetermined format, or the data recorded in the audio memory 4 is read out. To be supplied.

Further, a recording button (REC), a reproduction button (PL), a stop button (S
T), fast forward button (FF), fast reverse button (RE
W), an operation input unit 9 including operation buttons such as an erase button (ERASE) and a voice activation (voice active detector) button (VAD), and a power supply 10 of the voice recording / reproducing apparatus.

Next, the operation of the audio recording / reproducing apparatus of this embodiment having the above-described configuration will be described with reference to the flowchart shown in FIG.

First, the recording button (RE) of the operation input section 9
When C) is turned on (step S1), the system control unit 3 starts a recording operation. Next, the system control unit 3 detects whether or not a recording stop operation has been performed by operating a stop button (STOP) or the like (step S2). If the recording button is not turned on in step S1,
If a recording stop operation is performed in step S2, the process returns to the main routine of the audio recording / reproducing apparatus (not shown).

If the recording stop operation is not performed in step S2, the system control unit 3 controls each circuit so as to perform the operation after step S3. First, the microphone array 1 is controlled to control one frame (for example, 20 frames).
ms) (step S3). At this time,
The audio signal input by each microphone 11 of the microphone array 1 is input to an A / D converter 14 via a preamplifier 12 and a low-pass filter 13, respectively. And
Digital audio data of each A / D converter 14 is input to the direction estimating unit 15.

The direction estimating section 15 estimates the arrival angle θ of the voice based on the voice information from the microphone 11 (step S4), and sends the information to the system control section 3.
The system control unit 3 determines that the absolute value of the arrival angle θ of the voice estimated by the direction estimating unit 15 is a predetermined threshold value (for example, 20
°) is determined (step S5). Here, if the absolute value of the arrival angle θ is larger than the predetermined threshold, the system control unit 3 determines that the speaker has been changed, and records the current address value in the index information area 4a of the voice memory 4. (Step S6). Thereafter, the process proceeds to step S7.

In step S5, if the absolute value of the angle of arrival θ is not larger than the predetermined threshold value, the system control unit 3 controls the sound collection control unit 16 to output the sound signals output from the microphones 11 to each other. Then, based on the arrival angle of the sound obtained by the direction estimating unit 15, a sound collecting process for collecting the sound into one channel is performed (step S7).

The audio data collected by the sound collection control unit 16 is appropriately encoded by the digital signal processing unit 2 under the control of the system control unit 3 (step S8). This encoded data is recorded in the audio data area 4b of the audio memory 4 (step S9).

Thereafter, the system control unit 3 determines in step S
Returning to step 2, unless the recording stop operation is performed, the sound for the next one frame is input (step S3), and the same processing as above is repeated.

FIG. 4 is an explanatory diagram showing an example of a case where the audio recording / reproducing apparatus of the present embodiment is applied to a conference. In this case, the audio recording / reproducing apparatus of the present embodiment can be arranged at an arbitrary position with respect to a plurality of speakers, but it is preferable that the elevation angle between the adjacent speakers be a predetermined angle (in the present embodiment, 20 degrees). °) or more (for example, as shown in FIG. 4), it functions most effectively.

As described above, in the audio recording / reproducing apparatus of this embodiment, the direction estimation unit 15 always detects the angle of arrival of the audio under the control of the system control unit 3 during the recording operation. And when the arrival angle of the voice becomes larger than the predetermined angle,
(In this case, it is expected that the speaker has been changed.) Then, the index information at that time is written in the predetermined area 4a to correspond to the new speaker.

As described above, in the audio recording / reproducing apparatus of this embodiment, the index information is automatically recorded for each speaker. Since the sound is recorded at the natural position, the voice search can be performed more reliably.

In the audio recording / reproducing apparatus of the present embodiment, index information is automatically recorded for each speaker. However, the present invention is not limited to this, and an audio file is updated instead of recording index information. You may do it. As described above, the same effect can be obtained even when the audio information is recorded on the recording medium by performing predetermined division such as updating the audio file.

[Appendix] According to the embodiment of the present invention as described in detail above, the following configuration can be obtained. (1) In a voice recording / reproducing apparatus for recording and reproducing voice using a recording medium, a voice input unit having a plurality of microphones, and a direction for estimating an arrival direction of the voice based on an output of the voice input unit An estimating unit, a sound collection control unit that records the sound input from each microphone based on the arrival direction of the sound obtained by the direction estimation unit, and records the sound collected and controlled by the sound collection control unit on a recording medium. And recording means for recording position information indicating an arbitrary position of the sound on the recording medium as index information,
An audio recording / reproducing apparatus, wherein the recording means records the index information when the arrival direction of the audio estimated by the direction estimating means changes by a predetermined value or more.

(2) In a voice recording / reproducing apparatus for recording and reproducing voice using a recording medium, voice input means provided with a plurality of microphones, and an arrival direction of the voice is estimated based on an output of the voice input means. A direction estimating unit, a sound collection control unit that receives a sound input from each microphone based on an arrival direction of the sound obtained by the direction estimation unit, and a recording medium that receives the sound collected and controlled by the sound collection control unit. Recording means for recording in the, the recording means,
An audio recording / reproducing apparatus characterized by updating an audio file when the arrival direction of the audio estimated by the direction estimating means changes by a predetermined value or more.

(3) In a voice recording / reproducing apparatus for recording and reproducing voice using a recording medium, a detecting means for detecting a change of a speaker, and recording of information on the recording medium based on an output of the detecting means. And a control unit for changing and recording the system.

(4) The control means generates index information for retrieving audio information recorded on the recording medium based on the output of the detecting means, and generates the index information based on a predetermined value of the recording medium. The audio recording / reproducing apparatus according to the above (3) for recording in the area of (3).

(5) The voice recording of (3), wherein the control means divides the file for recording the voice information on the recording medium based on the output of the detection means, and records the voice information according to the classification. Playback device.

(6) The voice recording / reproducing apparatus according to (3), wherein the detection means detects a direction of arrival of the voice and detects a switch of the speaker.

(7) The detecting means includes a plurality of microphones (sound collecting means), a direction estimating means for calculating a sound signal detected by each of the microphones and estimating a direction of arrival of sound, and a detecting means for the direction estimating means. The audio recording / reproducing apparatus according to (6), further comprising: comparing means for comparing the output value with a predetermined value, and detecting the switching of the speaker based on the output of the comparing means.

(8) The audio recording / reproducing apparatus according to (7), wherein the direction estimating means estimates the arrival of the sound based on the time difference between the sound waves arriving at the microphones.

(9) There is provided a sound pickup control unit for controlling sound pickup of the sound input from each of the microphones based on the arrival direction of the sound obtained by the direction estimating means. The audio recording / reproducing apparatus according to (7), wherein the directivity is adjusted in the direction.

(10) In a voice recording / reproducing apparatus for recording and reproducing voice using a recording medium, a detecting means for detecting a change of a speaker, and index information for retrieving voice information recorded on the recording medium And a recording unit for recording the audio information and the index information on the recording medium automatically, based on an output of the detection unit.

(11) In a voice recording / reproducing apparatus for recording and reproducing voice using a recording medium, a detecting means for detecting a change of a speaker, and a recording file of voice information recorded on the recording medium, An audio recording / reproducing apparatus, comprising: means for automatically classifying based on the output of the audio data; and recording means for recording the audio information on the recording medium in accordance with the classification.

[0050]

As described above, according to the present invention, it is possible to provide an audio recording / reproducing apparatus for more reliably searching audio information.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram showing a configuration of an audio recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a recording area of an audio memory in the audio recording and reproducing apparatus of the embodiment.

FIG. 3 is a flowchart showing an index information adding operation in the audio recording / reproducing apparatus of the embodiment.

FIG. 4 is an explanatory diagram showing an example of a case where the audio recording / reproducing device of the embodiment is applied in a meeting place.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Microphone array 2 ... Digital signal processing part 3 ... System control part 4 ... Audio memory 4a ... Index information area 4b ... Audio data area 11 ... Microphone 15 ... Direction estimation part 16 ... Sound collection control part

Claims (3)

[Claims] 1. An audio recording and reproducing apparatus for recording and reproducing audio using a recording medium, comprising: detecting means for detecting an incoming direction of the audio; and a state of recording information on the recording medium based on an output of the detecting means. A sound recording and reproducing apparatus, comprising: control means for controlling the following. 2. An audio recording / reproducing apparatus for recording and reproducing audio using a recording medium, comprising: an audio input unit having a plurality of microphones; and a direction for estimating an arrival direction of the audio based on an output of the audio input unit. Estimating means, and recording means for recording, on the recording medium, position information indicating a desired position of the sound as index information together with the sound information obtained by the sound input means, wherein the recording means A sound recording / reproducing apparatus, wherein the index information is recorded when the arrival direction of the sound estimated by the estimating means changes by a predetermined value or more. 3. An audio recording / reproducing apparatus for recording and reproducing audio using a recording medium, comprising: audio input means having a plurality of microphones; and a direction for estimating an arrival direction of the audio based on an output of the audio input means. Estimating means, and recording means for performing predetermined division on the audio information obtained by the audio input means and recording the information on the recording medium, wherein the recording means estimates the direction by the direction estimating means. An audio recording / reproducing apparatus characterized in that when the direction of arrival of audio changes by a predetermined value or more, the classification is performed and audio information is recorded.