JP2870395B2 - Stereophonic sound reproducer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional sound reproducing apparatus for detecting the presence or absence of a listener and reproducing three-dimensional sound.

[0002]

2. Description of the Related Art Conventionally, as an apparatus for reproducing sound,
For example, as shown in Japanese Utility Model Laid-Open No. 01-101288, there has been a device that aims to give a strong impression to a listener by using sound as an advertising medium. This device has a voice synthesizer on the back of a poster and is equipped with a sounding body such as an earphone or headphones. The voice synthesizer is activated by the switch means and is electrically connected to a sounding body such as an earphone. The user can hear the announcement contents by touching these sounding bodies.

[0003]

This conventional device requires a sounding body such as an earphone or a headphone in order to reduce the leakage of sound to the outside. Therefore, the listener has to pick up the sounding body, and the sound can be reproduced only by a limited number of listeners. Further, when used as a public notice, it is necessary to pick up the sounding body and intentionally listen to the contents of the public notice.

[0004] An object of the present invention is to provide an apparatus capable of reproducing sound to a larger number of listeners without limiting the number of listeners by eliminating the need to wear a sounding body such as earphones or headphones. It is in. Another object of the present invention is to provide a device that reproduces various three-dimensional sounds and draws the attention of many listeners. Therefore, even when used as an advertising medium,
It is possible to provide a device having a high notification effect.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a stereophonic sound reproducing apparatus according to the present invention comprises a listener detecting means for detecting the appearance of a person who listens to sound, and a method for reproducing sound data. A localization coefficient changing unit that sets a localization coefficient that is output position information, a volume changing unit that changes a volume, and receives a listener detection signal issued by the listener detecting unit,
Controlling means for changing the localization coefficient held by the localization coefficient changing means and changing the volume held by the volume changing means; an audio data storage unit for holding audio data; receiving the localization coefficient and the sound; And sound reproducing means for reproducing the sound data stored in the data storage unit.

[0006]

The stereophonic sound reproducing apparatus according to the present invention detects the appearance of a person by using an infrared sensor or an ultrasonic sensor, and performs a stereophonic sound reproduction so that only the person can hear when a listening person exists. . This eliminates the need for switch means for generating sound, and outputs a three-dimensional sound that can be heard only by the listener, thus avoiding the problem of sound leakage to the surroundings. Furthermore, by changing the localization coefficient, for example, the output sound changes time,
A three-dimensional sound reproducing device capable of outputting various three-dimensional sounds can be provided.

[0007]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.

In FIG. 1, a listener detecting means 11 detects the presence or absence of a listener within a range in which sound is to be reproduced. As a method of detecting a listener in the listener detecting means 11, an infrared sensor, an ultrasonic sensor, an optical sensor, or the like can be used.

The localization coefficient changing means 12 outputs a localization coefficient, which is output information when audio data is reproduced.

The localization coefficient changing means 13 outputs data describing the time change of the volume. This volume data is used when sound is reproduced. The setting of the volume is performed by a user who uses this device for an advertisement medium or the like. The volume can be set to a fixed value or can be changed with time.

The sound data storage section 16 stores sound data. The user stores in the sound data storage unit 16
Sound data can be stored, and addition and deletion can be performed. The acoustic data that can be stored include, for example,
There are data recorded on a CD or the like, data recorded on a DAT or the like.

The sound reproducing means 15 includes a sound data storage unit 1
6 receives the acoustic data output from the localization coefficient changing unit 12 and the volume changing unit 13
Sound reproduction is performed using the volume data output from the. Sound can be reproduced using a transaural reproduction method, a multi-channel sound field reproduction method, or the like.

The control means 14 controls the change of the localization coefficient in the localization coefficient changing means 12 and the control of the volume change in the volume changing means 13. The user of this device can change the program of the control means 14 to
The localization coefficient of the localization coefficient changing means 12 can be changed. Thereby, for example, a variety of three-dimensional sounds can be output such that the three-dimensional sounds output to the listener change in time.

Next, the operation of FIG. 1 will be described. A user who uses this apparatus for an advertisement medium or the like gives sound data to the sound data storage unit 16. Also, the localization coefficient changing means 1
When it is necessary to change the localization coefficient of 2 or the volume output by the volume changing unit 13, the user changes the program of the control unit 14.

When a listener appears within a range in which sound is to be reproduced, the listener detector 11 detects the presence of the listener and sends a signal to the controller 14. The control unit 14 having received the signal outputs the localization coefficient of the localization coefficient changing unit 12 and the volume of the volume changing unit 13 to the sound reproducing unit 15 at the same time. When the localization coefficient and the sound volume are input, the sound reproducing unit 15 reads the sound data from the sound data storage unit 16 and performs sound reproduction based on the localization coefficient and the sound volume.

FIG. 2 is a block diagram showing a specific configuration of the sound reproducing means 15 given as an embodiment of the present invention.

The filter 21 receives the localization coefficient output from the localization coefficient changing means 12 and the volume output from the volume changing means 13. These data are output from the localization coefficient changing unit 12 by the control unit 14, and are set so that the path from the right speaker to the left ear and from the right ear to the left ear are canceled for each filter. The sound data sent from the sound data storage unit 16 is the filter 2
1 and to the speaker 23 through the amplifier 22.

FIG. 3 is a block diagram showing a specific configuration of hardware for realizing the embodiment of the present invention.

The sensor 31 is an example of the listener detecting means 11 in FIG. 1, and detects a listener. DSP3
Numeral 2 is an example of realizing the localization coefficient changing unit 12 and the volume changing unit 13, and performs calculation of the localization coefficient and setting of the volume. The CPU 34 and the CPU memory 35 are examples for realizing the control unit 14 in FIG. CPU memory 35
Holds a program for calculating the localization coefficient and setting the volume, and the like. The CPU 34 changes the program held in the CPU memory 35 and controls the DSP 32.

FIG. 4 shows a DSP for implementing an embodiment of the present invention.
3 is a flowchart of a specific process of the CPU and FIG.

The CPU checks whether there is any change in the program, and if so, writes the program, controls the DSP, and ends the processing.

The DSP waits for a signal from a sensor indicating the appearance of a listener, and upon receiving the signal, calculates a localization coefficient which is a transfer function for setting a filter. The localization coefficient can be obtained by the following Expressions 5 and 6.

A speaker signal s (t) at a certain position
And the respective signals e ₁ heard by the listener's left and right ears
Assuming that the relationship between (t) and _er (t) is linear, the output of a linear system is described by the convolution of its impulse response with the input signal. Thus, each of the signal heard by the ear, using an impulse response h _1, h _r of each route to ears of the left and right from the speaker,

[0025]

Can be expressed as Expressing this in the frequency domain, E _L = H _L S (3) E _R = H _R S (4) When listening to two speakers, E _L = S _{L HLL} + S _{R HRL} (5) E _R = _SR H _RR + _SL H _LR (6) When the speaker output is obtained from Expressions 5 and 6,

[0027]

May be set for the filters 211 to 214 in order.

[0029]

As described above, the three-dimensional sound reproducing apparatus according to the present invention can output a variety of three-dimensional sounds, and can reproduce sound with a high effect for a listener in applications such as advertisements. Can be.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a block diagram illustrating a specific configuration of a sound reproducing unit according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a specific configuration of hardware for realizing an embodiment of the present invention.

FIG. 4 is a flowchart of a process (program) executed by the DSP of FIG. 3 as an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Listener detection means 12 Localization coefficient change means 13 Volume change means 14 Control means 15 Sound reproduction means 16 Sound data storage unit 21 Filter 22 Amplifier 23 Speaker 31 Sensor 32 DSP 33 Bus 34 CPU 35 CPU memory

Claims (1)

(57) [Claims] 1. A sound reproducing apparatus for reproducing three-dimensional sound, comprising: a listener detecting means for detecting appearance of a person who listens to sound; and a localization for setting a localization coefficient which is output position information when reproducing sound data. Coefficient changing means, volume changing means for changing the volume, receiving a listener detection signal emitted by the listener detecting means, and changing the localization coefficient held by the localization coefficient changing means and the volume held by the volume changing means. Control means for changing, a sound data storage unit for holding sound data, and sound reproduction means for receiving the localization coefficient and the sound and for reproducing sound data held in the sound data storage unit. Three-dimensional sound reproduction device.