JP2003092799A - Acoustic processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an acoustic processor that allows a listener to listen to a sound in a proper state at all times even when a position of the head of the listener is not constant with respect to a speaker placed on a chair or a headrest. SOLUTION: Super-tweeters SL, SR emit an ultrasonic wave, a detection section 40 detects a positional relation between the tweeters SL, SR and the head of the listener by receiving a reflected wave of the ultrasonic wave in the head of the listener, a CPU 50 reads a coefficient fed to each filter of a trans-aural system filter section 20 from a database 60, supplies the coefficient to each filter so as to conduct processing of each filter of the trans-aural system filter section 20 according to the relation of position between the tweeters and the head of the listener.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound processing apparatus, for example, in which a speaker is provided in a chair or a headrest, and sound is emitted from the rear side of the listener's head.

[0002]

2. Description of the Related Art Chairs provided with a speaker on a backrest portion, a reclining chair having a headrest (head support portion) provided with a speaker, and the like have been provided. As described above, by providing the speaker on the back portion of the chair or the headrest, the speaker can be provided in the vicinity of the listener's ear.

As described above, by using a chair or a headrest provided with a speaker, high-quality sound is emitted near the listener's ear and provided to the listener. ing. That is, an environment has been prepared in which a listener can hear high-quality sound through a speaker positioned near the listener's ear without using headphones or the like.

[0004]

By the way, when a speaker is provided on the backrest portion or the headrest of a chair, high-quality sound can be emitted in the vicinity of the listener's ear, but behind the listener's ear. Since the sound is directly emitted from the side, the listener's consciousness is attracted to the rear of the listener, and depending on the music being listened to, there may be a sense of discomfort or so-called listening fatigue.

When a listener uses a chair or headrest provided with a speaker, the positional relationship between the speaker and the ear of the listener varies depending on the time of use, and the chair and headrest are always kept under the same conditions. It is difficult to hear the sound emitted from the speaker provided.

However, the position of the listener's head is forcibly so that the position of the listener's head (the position of the ear) is always the same with respect to the speaker provided inside the chair or headrest. It is not preferable to regulate the above because it impairs the listener's relaxed feeling. Moreover, since the head is not always in contact with the chair or the headrest, it is difficult to fix the position of the listener's head with respect to the speaker.

In view of the above, the present invention does not cause a sense of discomfort even if the position of the listener's head (the position of the ear) with respect to the speaker provided on the chair or the headrest is not constant, and it is always in an appropriate state. It is an object of the present invention to provide a sound processing device that enables a user to hear a generated sound.

[0008]

In order to solve the above-mentioned problems, a sound processing apparatus according to a first aspect of the present invention provides a speaker device and a voice signal to be supplied to the speaker device. Depending on the position of the listener's head with respect to the speaker device, a sound image localization processing unit that performs processing to localize a sound image of a sound by a signal and a sound signal from the sound image localization processing unit. Correction processing section for performing the correction processing, a head position detecting section for detecting the position of the listener's head with respect to the speaker device, and the correction processing according to the detection result from the head position detecting section. And a control unit configured to control the processing unit.

According to the sound processing apparatus of the first aspect, the sound signal supplied to the speaker device is so arranged that the sound image localization processing section localizes the sound image of the reproduced sound by the sound signal at a predetermined position. After the processing, a correction process is performed in consideration of the speaker device and the position of the listener's head (the position of the listener's ear), and the sound image of the sound emitted from the speaker device is localized at a predetermined position. To be done.

The head position detecting section detects the actual position of the listener's head with respect to the speaker device. The control unit controls the correction processing unit based on the detection result, and the correction processing unit performs the correction process according to the position of the listener's head on the audio signal after the sound image localization process.

As a result, even if the positional relationship between the speaker device and the listener's head changes, the voice of the processed voice signal can be reproduced without deteriorating the effect of the sound image localization performed on the voice signal. To be able to hear well.

The sound processing apparatus according to a second aspect of the present invention is the sound processing apparatus according to the first aspect, wherein the head position detecting section includes ultrasonic wave transmitting means for transmitting an ultrasonic wave.
Ultrasonic receiving means for receiving reflected ultrasonic waves transmitted from the ultrasonic wave transmitting means and reflected by the listener's head, presence / absence of reception of reflected ultrasonic waves by the ultrasonic wave receiving means, and the ultrasonic wave reception When the reflected ultrasonic wave is received by the means, the position of the listener's head with respect to the speaker device is specified based on the speed of the ultrasonic wave and the time from the transmission of the ultrasonic wave to the reception of the reflected ultrasonic wave. And a head position specifying means.

According to the acoustic processing device of the second aspect, the presence / absence of reflected ultrasonic waves and the ultrasonic waves transmitted from the ultrasonic wave transmitting means are reflected by the listener's head and are transmitted by the ultrasonic wave receiving means. The position of the listener's head with respect to the speaker device is specified by the head position specifying means on the basis of the time until reception and the speed of the ultrasonic wave, and the position of the listener's head is specified at the specified position of the listener. Accordingly, the correction processing unit is controlled by the control unit.

As described above, by using the ultrasonic wave transmitting means and the ultrasonic wave receiving means provided at a specific position with respect to the speaker device, the speaker device and the listener listening to the sound using the speaker device can be used. The positional relationship with the head can be detected reliably and accurately, and based on this, the correction processing in the correction processing unit can be appropriately controlled.

The sound processing apparatus according to a third aspect of the present invention is the sound processing apparatus according to the second aspect, wherein the ultrasonic wave transmitting means and the ultrasonic wave receiving means are of the speaker device. It is a high-range speaker.

According to the third aspect of the sound processing apparatus, the ultrasonic wave transmitting means and the ultrasonic wave receiving means for detecting the positional relationship between the speaker device and the position of the listener's head are the speaker device. The high range speaker of is used.
That is, the high frequency range speaker itself is used as the ultrasonic wave transmitting means and the ultrasonic wave receiving means.

Thus, in order to detect the positional relationship between the speaker device and the listener's head, the existing high-frequency range speaker can be ultrasonically converted without newly providing ultrasonic wave transmitting means and ultrasonic wave receiving means. It is possible to detect the relationship between the speaker device and the listener's head by using the transmitter and the ultrasonic receiver.

Further, the sound processing device according to a fourth aspect is
The acoustic processing apparatus according to claim 2, wherein the ultrasonic wave transmitting means is a high-range speaker of the left and right two-channel speaker device, and the ultrasonic wave receiving means is arranged in plural at predetermined positions. It is characterized in that it transmits ultrasonic waves of different frequencies from the treble speakers of the left and right channels respectively.

According to the sound processing apparatus of the present invention, the high-range speaker of the left and right channel speaker devices is used as the ultrasonic wave transmitting means, and the ultrasonic wave receiving means is, for example, in the vicinity of the ultrasonic wave transmitting means. A plurality of ultrasonic sensing elements having a so-called array structure are used.

Then, ultrasonic waves of different frequencies are transmitted from each of the high frequency speakers of the left and right channels,
By also considering the ultrasonic sensing element that senses the reflected ultrasonic waves reflected by the head of the listener of this ultrasonic wave,
The positional relationship between the speaker device and the listener's head can be detected more accurately.

Further, the sound processing apparatus according to claim 5 is
The sound processing apparatus according to claim 1, wherein the head position detection unit captures an image including a head of a listener who listens to sound through the speaker device, and the imaging unit. Image analysis means for analyzing the image captured by the means and detecting the position of the listener's head with respect to the speaker device.

According to the sound processing apparatus of the fifth aspect, the image including the head of the listener at the position for listening to the sound through the speaker device is captured by the image capturing means.
The imaged image is analyzed by the image analysis means, and the positional relationship between the speaker device and the listener's head is detected.

Thus, the positional relationship between the speaker device and the listener's head is accurately detected based on the image containing the listener's head at the position where the sound is heard through the speaker device, and in response thereto. The correction processing in the correction processing unit can be controlled appropriately.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a sound processing apparatus according to the present invention will be described below with reference to the drawings. In the embodiments described below, for example, a headrest portion (head support portion) provided in a seat of an automobile.
A sound processing device configured by mounting a speaker on a headrest portion of a chair used at home will be described as an example.

[First Embodiment] FIG. 1 is a block diagram for explaining a sound processing apparatus 1 of a first embodiment to which the present invention is applied, and FIG. 2 shows the first embodiment. It is a figure for demonstrating the external appearance of the chair with which the acoustic processing apparatus of embodiment is mounted. The sound processing device 1 according to the first embodiment is capable of processing audio signals of left and right two channels.

In FIG. 1, a disc 100 is a disc that provides 2-channel audio signals (2ch sound source (ch is an abbreviation for channel)). The left and right two-channel audio signals reproduced from the disc 100 are supplied to the sound processing apparatus 1 of the first embodiment shown in FIG.

Therefore, as shown in FIG. 1, the sound processing apparatus 1 of the first embodiment has a left channel input terminal Lin for receiving the supply of the left channel audio signal from the disc 100 which is a 2ch sound source. , A right channel input terminal Ri for receiving the right channel audio signal supply
n and.

As shown in FIG. 1, the acoustic processing apparatus 1 according to the first embodiment has a sound image localization processing filter unit 10, a transaural system filter unit 20,
A headrest unit 30, a head position detection unit (hereinafter, simply referred to as a detection unit) 40, a CPU (Central Pro)
processing unit 50 and a coefficient database for the transaural system filter unit 20 (hereinafter,
Simply called a database. ) 60 and.

As shown in FIG. 1, the headrest portion 30 is a portion provided with a left speaker (left channel speaker) SL and a right speaker (right channel speaker) SR as left and right two-channel speakers. As shown in FIG. 2, the headrest portion 30 corresponds to a portion (head supporting portion) that supports a user's head in a seat of an automobile, a chair used at home, or the like.

That is, as shown in FIG. 2, a so-called chair St such as a car seat or a reclining seat is
It is roughly divided into a seat portion St1 where the user sits down, a backrest portion St2 where the user's back rests, and a headrest portion St3 that supports the user's head. .

In the first embodiment, the headrest portion 30 shown in FIG. 1 is constructed by providing at least left and right two-channel speakers SL and SR in a portion corresponding to the headrest portion St3 shown in FIG. I am trying. Therefore, the listener (user) sitting on the chair provided with the headrest portion 30 listens to the sound emitted from the left speaker SL and the right speaker SR located diagonally behind his / her head. become.

The headrest portion may be removable like a car seat, or may be formed integrally with the backrest portion and the headrest portion alone cannot be removed. In the latter case, it can be said that a speaker is provided on the back portion of the chair.
In the first embodiment, the headrest portion 30
Is designed to be detachable from the backrest of a chair, for example.

In the sound processing device 1 according to the first embodiment, the sound localization is shifted from the position of the speaker, which is actually fixed, to the position of the virtual speaker. Discomfort and discomfort caused by hearing from near the back of the listener's head or behind the listener's ears are eliminated.

That is, in the first embodiment, the sound emitted from the left speaker SL and the right speaker SR of the headrest section 30 by the sound image localization processing filter section 10 and the transaural system filter section 20, Left virtual speaker VS indicated by a dotted line in FIGS. 1 and 2.
The sound is emitted from the position of the L, right virtual speaker VSR. In other words, the real speakers SL, S
The sound image of the sound emitted from R is generated by the virtual speakers VSL, V
The sound is localized so that it feels like the sound emitted from the SR.

In the first embodiment, the virtual speakers VSL, VSR are virtual positions for localizing the sounds emitted from the left speaker SL and the right speaker SR. As shown in, when the listener's head with respect to the headrest portion 30 is at a predetermined position, it is set at a predetermined position in the front direction of the listener.

As described above, the sounds emitted from the left speaker SL and the right speaker SR of the headrest portion 30 are localized as if they were emitted from the positions indicated by the left and right virtual speakers VSL and VSR. As described above, the discomfort and discomfort caused by the sound being heard near the back of the listener's head and behind the listener's ears are removed, and the listener can hear the sound as natural sound.

Hereinafter, each part of the sound processing apparatus of the first embodiment will be described in detail. First, in explaining the sound image localization processing filter unit 10, the principle of the sound image localization processing will be described. FIG. 3 is a diagram for explaining the principle of sound image localization processing.

As shown in FIG. 3, in a predetermined reproduced sound field, the position of the dummy head DH is set as the listener's position, and the listener's position at this dummy head DH is left and right to try to localize the sound image. The actual left speaker SP at the virtual speaker position (position where the speaker is supposed to be)
L, right real speaker SLR is installed.

Then, the sound emitted from the left real speaker SPL and the right real speaker SPR is picked up at both ears of the dummy head DH, and the sound emitted from the left real speaker SPL and the right real speaker SPR is A transfer function (HRTF) indicating how the dummy head DH changes when it reaches both ears is measured in advance.

As shown in FIG. 3, in the first embodiment, the left real speaker SPL is changed to the dummy head DH.
It is assumed that the transfer function of the sound to the left ear is M11, and the transfer function of the sound from the left real speaker SPL to the right ear of the dummy head DH is M12. Similarly, the right real speaker S
It is assumed that the transfer function of sound from PR to the left ear of the dummy head DH is M21, and the transfer function of sound from the right real speaker SPR to the right ear of the dummy head DH is M22.

As described above with respect to the headrest portion 30 of FIG. 1, the audio signals of the sound emitted from the speakers SL and SR of the headrest portion 30 which are located near the listener's ears are as described above. Then, the transfer function measured in advance is used for processing, and the sound of the processed sound signal is emitted.

As a result, the sound emitted from the speakers SL, SR of the headrest portion 30 is as if the sound is at the virtual speaker position (in FIG. 1 and FIG. 2, the virtual speaker VSL,
The sound image of the sound emitted from the speakers SL and SR can be localized so that the listener feels that the sound is emitted from the position (VSR position).

Although the dummy head DH is used when the transfer function (HRTF) is measured here, the invention is not limited to this. In the reproduced sound field for measuring the transfer function, actually sitting a human,
Of course, a microphone may be placed near the human ear to measure the transfer function of the voice.

The sound image localization processing filter unit 10 shown in FIG. 1 is a portion that performs processing by the transfer function of the sound that is measured in advance in order to localize the sound image at the predetermined position. The sound image localization filter processing unit 10 of this embodiment is capable of processing left and right two-channel audio signals. As shown in FIG. 1, four filters 11, 12, 13, 14 and two filters are provided. Adder 15,
It consists of 16.

The filter 11 transfers the left channel audio signal supplied through the left input terminal Lin to the transfer function M1.
The audio signal after processing is supplied to the adder 15 for the left channel. In addition, the filter 12
Is for processing the left-channel audio signal supplied through the left input terminal Lin with the transfer function M12,
The processed audio signal is supplied to the addition unit 16 for the right channel.

The filter 21 has a right input terminal Rin.
The audio signal of the right channel received through is processed by the transfer function M21, and the processed audio signal is supplied to the adding section 15 for the left channel. The filter 22 processes the right-channel audio signal supplied through the right input terminal Rin with the transfer function M22, and supplies the processed audio signal to the right-channel addition unit 16.

As a result, the addition unit 15 for the left channel
1 and FIG. 2, the left virtual speaker VSL and the right virtual speaker VS are the sound based on the output sound signal from the right channel and the sound based on the output sound signal from the adding section 16 for the right channel.
The sound image is localized so that sound is emitted from R.

However, as shown in FIG. 1, the sound emitted from the left speaker SL and the right speaker SR provided in the headrest portion 30 is actually reproduced in the sound field even if the sound image localization processing is performed. Transfer functions G11, G12,
In some cases, due to the influence of G21 and G22, the sound image of the reproduced sound cannot be accurately localized at the target virtual speaker position.

Therefore, in the first embodiment, the trans-aural system filter section 20 is used to perform correction processing on the audio signal from the sound image localization processing filter section 10, thereby providing a left speaker. S
The sound emitted from the L and right speakers SR is localized exactly as if it was emitted from the virtual speakers VSL and VSR on the left and right of the virtual speaker position.

Trans-aural system filter section 20
Is an audio filter formed by applying a transaural system. The trans-aural system is a technique for realizing the same effect as that of a binaural system method, which is a method for reproducing sound strictly using headphones, even when a speaker is used.

FIG. 1 shows the transaural system.
As an example, the transfer functions G11, G12, and G13 of the sound emitted from the left speaker SL and the right speaker SR to the left and right ears of the listener of the sound emitted from the respective speakers. , G14 to eliminate the influence of the left speaker SL, the right speaker SR
Strictly reproduce the sound emitted from.

Therefore, the trans-aural system filter section 20 shown in FIG. 1 removes the influence of the transfer function in the reproduced sound field from the left speaker SL and the right speaker SR by removing the influence of the transfer function. The sound image of the sound emitted from the speaker SL and the right speaker SR is accurately localized at a position corresponding to the virtual speaker position.

Specifically, the transaural system filter unit 20 removes the influence of the transfer function from the left speaker SL, the right speaker SR to the left and right ears of the listener.
Filters 21 and 2 for processing an audio signal according to the inverse function of the transfer function from the right speaker SR to the left and right ears of the listener.
2, 23, 24 and addition units 25, 26 are provided. In the first embodiment, the filter 2
In Nos. 1, 22, 23, and 24, processing is performed in consideration of the inverse filter characteristic so that a more natural reproduced sound can be emitted.

As will be described later in detail, the transfer functions from the left speaker SL and the right speaker SR to the left and right ears of the listener are determined by the positions of the left and right speakers SL and SR and the position of the listener's head (the listener). Position of the ear).
Therefore, in each of the filters 21, 22, 23, and 24 of the transaural system filter unit 20, the filter coefficient for each filter corresponding to the position of the head of the listener, which is stored in advance in the database 60, is stored in the CPU 5.
It can be set through 0.

The output audio signal from the adder 15 for the left channel of the sound image localization processing filter 10 is supplied to the filter 21 for the left channel and the filter 22 for the right channel of the transaural system filter 20. In addition, the output audio signal from the right-channel addition unit 16 of the sound image localization processing filter unit 10 is supplied to the left-channel filter 23 and the right-channel filter 24 of the transaural system filter unit 20. It

Each of the filters 21, 22, 23, 24 performs a predetermined process using the filter coefficient from the CPU 50. Specifically, as described above, the speakers SL, SR listen to each other. Inverse functions H1n, H2n, H3n, H of the transfer function according to the current head position of the person
4n is used to process the audio signal supplied to the own filter.

Each filter 21, 22, 23, 24
Inverse functions H1n, H2n, H3 of the transfer function used in
In n and H4n, n means a variable determined according to the position of the listener's head, and H1 and H which are characters other than n.
2, H3, and H4 are filters 21, 22, 23, and 2 in that order.
It is shown that it is a function used in each of the four.

The output from the filter 21 is supplied to the adder 25 for the left channel, and the output from the filter 22 is supplied to the adder 26 for the right channel.
Similarly, the output from the filter 23 is supplied to the adder 25 for the left channel, and the output from the filter 24 is supplied to the adder 26 for the right channel.

The adders 25 and 26 add the audio signals supplied thereto, the adder 25 supplies the audio signal to the left speaker SL, and the adder 26 adds the audio signal to the right speaker SR. To supply. As a result, the sound emitted from the speakers SL and SR of the headrest unit 30 is removed from the effect of the transfer function corresponding to the current position of the listener's head in the reproduced sound field, and its sound image is accurately left virtual. It is possible to localize like the sound emitted from the speaker VSL and the right virtual speaker VSR.

As described above, in the sound processing apparatus 1 according to the first embodiment, a listener whose head is located at a predetermined position near the headrest portion 30 emits sound from the speakers SL and SR of the headrest portion 30. Virtual speaker VS for sound
The sound can be heard as if it was emitted from the L, VSR.

Therefore, even though the sound emitted from the left speaker SL and the right speaker SR positioned diagonally behind the listener's head is heard, the sound is heard from the front direction of the listener. Left speaker S
Therefore, it is possible to allow the sound to be satisfactorily listened to without causing any discomfort or discomfort such that the sound emitted from the L or right speaker SR sticks behind the listener.

However, as described above, in the case of the sound processing device 1 shown in FIG. 1, the virtual speakers VSL, VSL.
The positional relationship from the virtual speaker position indicated by SR to both ears of the listener and the positional relationship from the speakers SL and SR to both ears of the listener are measured at the time of transfer function measurement and system reproduction (actually reproducing sound. And when listening to each other), each transfer function also changes, so
The effect of localizing the sound image to the virtual speaker position is weakened.

In the case of the sound processing apparatus 1 of the first embodiment, as shown in FIG. 1, the transfer function from the speakers SL, SL of the headrest section 30 to the listener's ear is the transfer function G11, When the listener's head is at the position of G12, G21, G22, whether the listener emits the sound emitted from the speakers SL and SR of the headrest unit 30 from the virtual speakers VSL and VSR. Can be heard as.

However, the speaker S of the headrest portion 30
If the position of the listener's head with respect to L and SR deviates from the assumed position, the speaker S is set to the virtual speaker position.
The virtual speaker localization effect that localizes the sound image of the sound emitted from L and SR cannot be sufficiently obtained.

In particular, when the listener's head moves in a direction orthogonal to the speaker's sound emitting surface, when the listener's head moves in a vertical direction or a horizontal direction parallel to the speaker's sound emitting surface. The effect is larger than that in the case of moving to approach the speaker or move away from the speaker.

Therefore, in order to obtain the effect of virtual speaker localization, the position of the listener's head (ear position) with respect to the speaker is always set to a fixed position, and the listener listens to the sound or listens to the sound. It is desirable to measure the transfer functions at various head positions in the above and reproduce the voice by a system that has a transfer function or an inverse filter suitable for the positions.

However, it is difficult to always keep the position of the head of the listener sitting on the chair having the headrest portion 30 at a predetermined position with respect to the speaker.
Further, even if it can be held, it may rather impair the listener's relaxed feeling.

Therefore, in the sound processing apparatus 1 of the first embodiment, when the sound processing apparatus 1 is in the operating state, for example, at every predetermined timing, from the headrest portion 30 to the listener's head. Measure distance and position,
By supplying the filter coefficient corresponding to the measured position of the listener's head to each filter of the transaural system filter unit 20, an audio signal after the sound image localization processing is obtained according to the latest position of the listener's head. A correction process is performed on the other hand.

By doing so, even if the position of the listener's head changes with respect to the headrest portion 30, that is, the speakers SL, SR, due to the movement of the listener's head, the virtual position is assumed. The virtual speaker localization effect that localizes the sound image to the speaker position does not deteriorate, and the sounds from the left and right speakers SL and SR of the headrest portion 30 can be heard in a more free posture.

In the sound processing apparatus 1 of the first embodiment, the super tweeter of the speaker mounted on the headrest section 30 is used as the position detecting sensor for the listener's head. In recent years, it is not uncommon to install a speaker having a reproduction performance higher than the audible frequency band due to the progress of HiFi for reproduction audio, and this is utilized.

As described above, the super tweeters of the speakers SL and SR of the sound processing apparatus 1 according to the first embodiment have a reproduction capability above the audible frequency, and the speaker (speaker device) having this configuration is used. By using it for measuring the position of the listener's head, it is configured so that it is not necessary to mount a dedicated sensor system such as a pressure-sensitive type.

Then, the speaker S of the headrest portion 30
Ultrasonic waves of a predetermined frequency are transmitted from the super tweeters L and SR, and the reflection of the ultrasonic waves mainly from the head of the listener is received through the super tweeters SR and SL of the headrest section 30, and the ultrasonic waves are received. Whether or not the reflected wave is received, and when the reflected wave is received, the time taken from the transmission of the ultrasonic wave to the reception of the reflected wave, and the speaker obtained from the time and the speed of the ultrasonic wave. The position of the listener's head with respect to the headrest portion 30 is detected based on the distance to the listener.

FIG. 4 is a diagram for explaining the process of detecting the position of the listener's head performed by the sound processing device 1 according to the first embodiment. As shown in FIG. 4, ultrasonic waves of 40 kHz are transmitted from the super tweeters of the left and right speakers SL and SR of the headrest section 30, and the reflected wave from the head of the user of this ultrasonic wave is also transmitted to the headrest section 30.
It is received by the super tweeters of the left and right speakers SL and SR.

Control of transmission of ultrasonic waves from the super tweeters of the left and right speakers SL and SR is controlled by, for example, the CPU 50. Then, the left and right speakers SL, SR
The ultrasonic waves received by the super tweeter are supplied to the detection unit 40. In this detection unit 40, the presence / absence of ultrasonic waves (reflected waves) of 40 kHz and 40 kHz
When the ultrasonic wave (reflected wave) of z is received, the position of the listener's head with respect to the left and right speakers SL, SR of the headrest unit 30 is determined from the time taken from the transmission of the ultrasonic wave to the reception, the speed of the ultrasonic wave, and the like. To detect.

That is, as shown in FIGS. 4A and 4B, when each of the super tweeters of the speakers SL and SR of the headrest section 30 similarly receives the reflected wave of the ultrasonic wave transmitted in the same manner, The position of the listener's head with respect to the headrest portion 30 can be detected according to the time taken from to reception.

Briefly, for example, as shown in FIG. 4A, when the time taken from the transmission of ultrasonic waves to the reception of ultrasonic waves is relatively long, the listener's head will not move to the headrest portion 3.
It can be seen that it is located relatively far from 0. Further, as shown in FIG. 4B, when the time taken from the transmission of ultrasonic waves to the reception thereof is relatively short, the position of the listener's head is relatively close to the headrest portion 30. You can see that

Also, as shown in FIG. 4C, only the super tweeter of the left speaker SL receives the ultrasonic waves similarly transmitted from the super tweeters of the left and right speakers SL and SR provided in the headrest portion 30, and the right speaker. S
When the super tweeter of R does not receive the ultrasonic wave of 40 kHz, the listener's head is headrest part 30.
You can see that it is biased to the left.

On the contrary, for example, only the super tweeter of the right speaker SR receives the ultrasonic waves similarly transmitted from the super tweeters of the left and right speakers SL and SR provided in the headrest section 30, and the super tweeter of the left speaker SL If you do not receive 40kHz ultrasound,
It can be seen that the listener's head is offset to the right with respect to the headrest portion 30.

As described above, the detecting section 40 detects the distance of the headrest section 30 from the speakers SL and SR and the left and right offsets based on the reflected waves of the ultrasonic waves transmitted from the left and right speakers from the listener's head. (Displacement) can be sensed. In this case, the position of the listener's head is
For example, it is detected as a deviation (offset) from the reference position where the listener's head should originally be located, and this is detected by the CPU.
50 will be notified.

Then, the CPU 50 refers to the database 60 based on the detection result of the position of the listener's head from the detector 40, and the transaural system filter unit corresponding to the current position of the listener's head. 20 each filter 2
The coefficient data supplied to 1 to 24 are read.

In the first embodiment, the database 60 includes the transaural system filter unit 2
The coefficient data to be supplied to each of the filters 21, 22, 23, and 24 of 0, which is data corresponding to the position of the listener's head with respect to the headrest portion 30, is stored.

That is, the transfer function of the sound emitted from the speakers SL and SR of the headrest portion 30 to the left and right ears of the listener is measured by changing the position of the listener's head relative to the headrest portion 30 in advance. Incidentally, based on this measurement result, coefficient data used in each of the filters 21, 22, 23, and 24 of the transaural system filter section 20 is obtained, and the obtained coefficient data is associated with the position of the listener's head. The attached data is stored in the database 60.

Therefore, in the database 60, the positions of the listener's head are the filters 21, 22, 23, 2 of the transaural system filter unit 20 at the position A.
4, the coefficient data used in each of 4 and the filter 2 of the transaural system filter unit 20 at the position B.
The filter 21, 22, 23, 24 at each position of the listener's head whose position is changed with respect to the headrest 30 as in the coefficient data used in each of 1, 22, 23, 34. The coefficient data used in is stored.

Based on the detection result of the current position of the head of the user from the detection unit 40, the CPU 50 causes the filters 21, 22 of the transaural system filter unit 20,
The coefficient data to be supplied to 23 and 24 is read from the database 60 and supplied to the corresponding filter of the transaural system filter unit 20.

As a result, even if the position of the listener's head moves with respect to the headrest portion 30, the actual position of the listener's head is measured, and the transfer function of the reproduced sound field is determined according to the measured position. A correction process can be performed in the transaural system filter unit 20 so as to remove the influence. Therefore, the sound images of the sounds emitted from the left and right speakers SL and SR of the headrest portion 30 can be localized at the virtual speaker positions regardless of the position of the listener's head.

In the first embodiment,
The database 60 finds a function to be set in each filter at each position of the head based on the transfer function measured at each position that the listener's head can take, and associates this function with the position of the head. It may be stored in memory.
That is, the function itself used for the correction may be stored in the database in association with the position of the head, and set in the target filter of the transaural system filter unit.

Further, as in the case of the above-mentioned first embodiment, for example, the transfer function at the reference position is measured,
Necessary parameters such as an amplitude adjusting parameter and a delay processing parameter for this reference transfer function are set, and a new parameter is set according to the actual position of the listener's head to be detected with reference to this reference parameter. You may make it obtain a parameter and set it for each filter.

That is, one transfer function model is set,
By adjusting this model according to the position of the listener's head, it is also possible to perform correction processing on the audio signal according to the actual position of the listener's head. it can. In this case, as a reference model,
If the parameters that can be placed at the reference position are held in a program executed by the CPU, for example, a memory for holding the parameters is not necessary, and if only the reference parameters are held in the memory, It does not require large memory capacity.

As described above, the database 60
Stored in the transaural system filter unit 20.
As the processing information to be supplied to each filter, coefficient data, function data, parameter data,
Although a plurality of types can be considered, these may be used according to each filter circuit to be actually mounted in the sound processing device.

The database 60 is, for example, RO
It is a semiconductor memory such as M or EEPROM. A recording medium such as a magnetic disk, an optical disk, or a magneto-optical disk can be used as the database 60.

[Modification of First Embodiment] FIG. 5 is a block diagram for explaining a modification of the acoustic processing apparatus of the first embodiment. As shown in FIG. 5, the sound processing device 2 of this example includes a transaural system filter unit 2
It is configured similarly to the sound processing apparatus 1 of the first embodiment shown in FIG. 1 except that the simplified transaural system filter unit 70 is mounted instead of 0. For this reason, in the sound processing apparatus 2 shown in FIG. 5, the same components as those of the first sound processing apparatus 1 shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted. .

As shown in FIGS. 1, 2 and 5, the headrest portion 30 and the listener's head are normally close to each other, and the speakers SL and SR of the headrest portion 3 are close to the listener's ears. Therefore, the crosstalk component from the speakers SL and SR to the ear on the opposite side is significantly smaller than the audio signal component from the speakers SL and SR to the ear on the side corresponding to the speaker.

That is, in the example shown in FIG. 1, the transfer functions G12 and G21 of the crosstalk component are the transfer functions G1.
Since it is much smaller than 1 and G22, the transfer functions G12 and G21 of the crosstalk component can be ignored. Therefore, the simplified transaural system filter unit 70 shown in FIG. 5 is simplified by omitting the consideration of the crosstalk component from the normal transaural system.

As shown in FIG. 5, the simplified transaural system filter section 70 has a headrest section 30.
A filter 71 that processes an audio signal with an inverse function of the transfer function G1 of the audio from the left speaker SL to the listener's left ear;
And a filter 72 for processing an audio signal with an inverse function of the transfer function G2 of the audio from the right speaker SR to the right ear of the listener. As described above, it has been confirmed by experiments that the sound localization is at the virtual speaker position even when the crosstalk component is ignored.

Then, each of the two filters 71 and 72 of the simplified transaural system filter unit 70 actually corresponds to the actual position of the head of the listener in the reproduced sound field, as will be described later. The function or coefficient data is set.

In this case, since only the data for the filters 71 and 72 need be prepared in the database 60, the amount of data stored and held in the database 60 can be reduced. Therefore, database 6
As 0, a memory having a small storage capacity can be used.

In the case of the sound processing device 2 shown in FIG. 5, the simplified transaural system filter section 70 is used.
By using, the configuration of the sound processing device can be simplified.

Also, in the case of the sound processing apparatus shown in FIG. 5, similarly to the case of the sound processing apparatus 1 of the first embodiment shown in FIG. 1, the sound processing apparatus is placed diagonally behind the head of the listener. Although the sound emitted from the left speaker SL and the right speaker SR located is heard, the sound is made to be heard from the front direction of the listener. Therefore, the sound is emitted from the left speaker SL and the right speaker SR. It is possible to make it possible to listen to the sound satisfactorily without causing any discomfort or discomfort such as the sound being heard sticking to the back of the listener.

[Second Embodiment] FIG. 6 is a block diagram for explaining an audio processing apparatus 3 according to a second embodiment of the present invention. The sound processing apparatus according to the second embodiment is capable of processing a sound signal from a multi-channel medium such as a DVD. In the second embodiment, a sound signal of 5 channels is used. Is something that can be processed.

As shown in FIG. 6, the sound processing apparatus 3 according to the second embodiment is provided with input terminals i1 to i5 for audio signals of 5 channels, and, for example, from a multi-channel recording medium such as a DVD. 5 channels of audio signals can be received. The sound processing apparatus 3 shown in FIG. 6 includes a headrest unit 30, a head position detection unit 40, a CPU 50, a database 60, a simplified transaural system filter unit 70, and a sound image localization processing filter unit 80.

The headrest portion 30 is the first one shown in FIG.
The sound processing device 1 of the embodiment and the headrest portion 30 of the sound processing device 2 of the modification of the first embodiment shown in FIG. 5 are configured in the same manner. Further, the simplified trans-aural system filter unit 70 is the simplified trans-aural system filter unit 70 of the sound processing device 2 of the modified example of the first embodiment described above with reference to FIG.
It is configured similarly to.

The sound image localization processing filter section 80 of the sound processing apparatus 3 of the second embodiment is basically
The sound image of the sound emitted from the speaker is localized based on the same principle as that of the sound image localization processing filter unit 10 of the acoustic processing apparatus according to the first embodiment.

However, in the sound processing apparatus of the second embodiment shown in FIG. 6, the sound image of the sound emitted from the left and right speakers SL, SR of the headrest portion 30 is shown by the dotted line in FIG. 5 virtual speakers VS1
It is localized as if it were being emitted from VS5.

FIG. 7 is a diagram for explaining the principle of the sound image localization processing filter section 80 of the acoustic processing apparatus 3 of the second embodiment shown in FIG. As shown in FIG. 7, in a predetermined reproduction sound field, the position of the dummy head DH is set as the position of the listener, and the virtual speaker position (the position of which the sound image is localized with respect to the listener at the position of the dummy head DH ( The actual speakers SP1 to SP5 are actually installed at positions where it is assumed that there are speakers. And the real speaker SP1
The transfer function (HRTF) of the sound emitted from each of SP5 to SP5 to the left and right ears of the dummy head DH is measured in advance.

As shown in FIG. 7, in the second embodiment, the transfer function of the sound from the real speaker SP1 to the left ear of the dummy head DH is N11, and the real speaker S
The transfer function of the sound from P1 to the right ear of the dummy head DH is N12. The transfer function of sound from the real speaker SP2 to the left ear of the dummy head DH is N21, and the transfer function of sound from the real speaker SP2 to the right ear of the dummy head DH is N22.

Similarly, the transfer functions of the sound from the real speaker SP3 to the left and right ears of the dummy head DH are N31 and N32, and the transfer of the sound from the real speaker SP4 to the left and right ears of the dummy head DH is performed. The functions are N41 and N42. The transfer functions of the sound from the real speaker SP5 to the left and right ears of the dummy head DH are N51 and N52.

Then, as described with reference to FIG. 7, the audio signals input from the input terminals i1 to i5 are processed using the corresponding transfer functions measured in advance, and the simplified transaural system filter is used. In the portion 70, the correction processing is performed, and the sound based on the sound signal after the processing is corrected to the left and right speakers SL, S of the headrest portion 30.
It is supplied to R to output sound.

As a result, the viewer feels that the sound emitted from the speakers SL and SR of the headrest section 30 is emitted from the positions indicated by the virtual speakers VS1 to VS5 indicated by the dotted lines in FIG. So that sound image can be localized.

As described above, in order to localize the sound image, the portion which performs the processing by the transfer function of the voice measured in advance is
The sound image localization processing filter unit 80 shown in FIG. As described above, the sound image localization filter processing unit 80 of this embodiment is capable of processing a 5-channel audio signal, and includes ten filters 81 to 90 and two addition units 91 and 92. It consists of and.

The filter 81 processes the audio signal supplied through the terminal i1 with the transfer function N11, and supplies the processed audio signal to the adder 91 for the left channel. The filter 82 processes the audio signal supplied through the terminal i2 with the transfer function N12, and the processed audio signal is added to the right channel adder 92.
Supply to.

The filter 83 processes the audio signal supplied through the terminal i2 with the transfer function N21, and supplies the processed audio signal to the adder 91 for the left channel. The filter 84 processes the audio signal supplied through the terminal i2 with the transfer function N22, and the processed audio signal is added to the right channel adder 92.
Supply to.

The filter 85 processes the audio signal supplied through the terminal i3 with the transfer function N31, and supplies the processed audio signal to the adder 91 for the left channel. The filter 86 processes the audio signal supplied through the terminal i3 with the transfer function N32, and the processed audio signal is added to the right channel adder 92.
Supply to.

The filter 87 processes the audio signal supplied through the terminal i4 with the transfer function N41, and supplies the processed audio signal to the adder 91 for the left channel. The filter 88 processes the audio signal supplied through the terminal i4 with the transfer function N42, and the processed audio signal is added to the right channel adder 92.
Supply to.

The filter 89 processes the audio signal supplied through the terminal i5 with the transfer function N51, and supplies the processed audio signal to the adder 91 for the left channel. The filter 90 processes the audio signal supplied through the terminal i5 with the transfer function N52, and the processed audio signal is added to the right channel adder 92.
Supply to.

Thus, the adder 91 for the left channel is used.
6 and the sound by the output sound signal from the adder 92 for the right channel are localized so that sound is localized from the positions of the virtual speakers VS1 to VS5 shown by the dotted lines in FIG. To be done.

Also in the case of the sound processing device 3 of the second embodiment, as in the case of the sound processing devices 1 and 2 of the first embodiment, the left speaker provided in the headrest portion 30. The sound emitted from the SL and the right speaker SR is localized at the target virtual speaker position of the sound image of the reproduced sound due to the influence of the transfer function in the actual reproduced sound field even if the sound image localization processing is performed. It is thought that there are cases where it cannot be done.

Therefore, also in the sound processing device 3 of the second embodiment, the left and right speakers S of the headrest unit 30 are used by using the simplified transaural system filter unit 70 which does not consider the crosstalk component.
The sound image of the sound emitted from L and SR is accurately localized at each position of each virtual speaker VS1 to VS5.

As described above, a medium having a multi-channel sound source such as a DVD has become widespread, but it is possible to process a 5-channel audio signal like the audio processing apparatus 3 of the second embodiment. By so doing, a virtual five-channel sound image can be obtained through the two speakers SL and SR of the headrest section 30, and a powerful reproduced sound can be enjoyed.

Further, even when the position of the listener's head with respect to the headrest portion 30 changes due to the listener's head moving, the sound processing apparatus 1, 2 of the first embodiment described above. The position of the listener's head with respect to the headrest unit 30 is detected, and the functions and parameters of the filters 71 and 72 of the simplified transaural system filter unit 70 are changed according to the position, as in the case of The sounds emitted from the left and right speakers SL and SR of the unit 30 can be localized at the virtual speaker positions.

That is, also in the second embodiment, the left and right speakers SL and SR of the headrest portion 30 are the same as in the case of the sound processing devices 1 and 2 of the first embodiment.
The super tweeter transmits an ultrasonic wave, and the super tweeter receives a reflected wave of the transmitted ultrasonic wave from the listener's head. Based on this, the detection unit 40 determines the position of the listener's head. The sound image can be localized at a predetermined virtual speaker position by detecting and correcting by the simplified transaural system filter unit 70 so as to remove the influence of the transfer function at that position.

In the second embodiment,
Although the simplified trans-aural system filter unit 70 is used, the trans-aural system filter 20 that also takes the crosstalk component into consideration is used as in the case of the acoustic processing apparatus 1 according to the first embodiment shown in FIG. You may use it.

Further, by providing all of the sound processing apparatus shown in FIGS. 2, 4 and 5 on the headrest section 30 side, the headrest section 30 of the sound processing apparatus of the first embodiment described above. As described above, by configuring the headrest portion to be removable from the backrest portion, even when the headrest portion is attached to the backrest portion of another chair, the sound image is always localized at a predetermined position. , It is possible to listen to the voice satisfactorily.

It is also possible to construct an adapter including each part other than the left and right speakers, and to configure the sound processing device according to the present invention with this adapter and the headrest part provided with the speaker. Further, the sound processing device of the present invention can be configured by providing each part other than the left and right speakers SL and SR, for example, on the backrest part of the chair or on the reproduction device side of the audio signal.

In the sound processing devices of the first and second embodiments described above, the super tweeters of the speakers SL and SR mounted on the headrest section 30 are used to detect the position of the listener's head. The ultrasonic wave is used as a transmitting unit and also as a receiving unit for receiving a reflected wave of the transmitted ultrasonic wave in the head of the listener.

Therefore, since it is not necessary to newly provide an ultrasonic wave transmitting unit and an ultrasonic wave receiving unit, it is possible to realize a sound processing apparatus equipped with a function of detecting the position of the listener's head relatively inexpensively. it can.

In the case of the above-described first and second embodiments, the position of the listener's head with respect to the headrest portion 30 is measured constantly or at any time, and the position is measured according to the measured position. By performing the correction processing (trans-aural processing) according to the transfer function, it is possible to avoid the conventional situation where the virtual speaker localization effect is insufficient due to the mismatch between the measurement position of the listener's head and the listening position, and to avoid the listener's head. It is possible to realize effects such as the front localization of the sound image as in the first embodiment and the omnidirectional localization of the sound image as in the second embodiment without being influenced by the position of the part.

[Third Embodiment] By the way, in order to realize a sound processing apparatus capable of providing higher-quality sound, the accuracy of detecting the position of the listener's head with respect to the headrest portion is increased, and the sound signal is detected. There is a demand for more precise correction processing by the trans-aural system with respect to.

Therefore, also in the sound processing apparatus of the third embodiment, ultrasonic waves for detecting the position of the listener's head are used as the sound processing apparatus of the first and second embodiments. In the same manner as in the above case, the signals are transmitted from the super tweeters of the speakers SL and SR provided in the headrest section 30.

However, in the acoustic processing apparatus of the third embodiment, the reflected waves of the transmitted ultrasonic waves are received by the headrest section 30 or a plurality of ultrasonic receiving elements provided in the vicinity thereof. The position of the listener's head can be detected more accurately.

FIG. 8 is a block diagram for explaining the sound processing apparatus 4 according to the third embodiment. As shown in FIG. 8, the sound processing device 4 according to the third embodiment includes left and right two-channel speakers SL and SR, a headrest 90 provided with a plurality of ultrasonic receiving elements, and a plurality of headrests 90. Except for the head position detecting unit 40A that receives the detection output from the receiving element, the acoustic processing device has the same configuration as that of the acoustic processing device according to the first embodiment shown in FIG. 1. Therefore, the third processing shown in FIG. In the sound processing device 4 of the embodiment of FIG.
The same parts as those of the sound processing apparatus 1 of the first embodiment shown in FIG.
The same reference numerals are given and the description of those portions will be omitted.

As described above, in the case of the acoustic processing device 4 of the third embodiment shown in FIG. 8, the headrest portion 90 has six ultrasonic receiving elements (ultrasonic sensing elements) SS1. ~ SS6 are provided in an array. Then, ultrasonic waves having different frequencies are transmitted from the super tweeter of the left channel SL and the super tweeter of the right channel SR, and the reflected waves are received by the ultrasonic wave receiving elements (hereinafter, simply referred to as receiving elements) SS1 to SS6. Based on the detection output, the detection unit 40A can detect the position of the listener's head more accurately.

FIG. 9 is a diagram for explaining the process of detecting the position of the listener's head, which is performed in the sound processing device according to the third embodiment. As shown in FIG. 9, ultrasonic waves of different frequencies are transmitted from the left and right speakers SL and SR whose sound emitting surfaces are originally oriented in the direction where the listener's head exists.
The reflected waves from the listener's head of the transmitted ultrasonic waves are received by the receiving elements SS1 to SS6.

In the case of the example shown in FIG. 9, the left speaker SL
The super tweeter of No. 2 transmits an ultrasonic wave having a frequency of 40 kHz, and the super tweeter of the right speaker SR transmits an ultrasonic wave of a frequency of 50 kHz. By doing so, the accuracy of position detection is further improved.

As shown in FIG. 9A, none of the receiving elements SS1 to SS6 provided in the headrest section 90 can receive the reflected waves of the ultrasonic waves transmitted from the super tweeters of the left and right speakers SL and SR. in case of,
The position of the listener's head can be detected as being located away from the headrest 90 by a predetermined distance or more.

As shown in FIG. 9B, the left speaker S
The listener of the ultrasonic waves transmitted from the super tweeter of L, that is, the reflected wave from the head of the listener, that is, the ultrasonic wave of 40 kHz is received by the receiving element SS3 and transmitted from the super tweeter of the right speaker SR. Waves reflected from the head of the user, that is, ultrasonic waves of 50 kHz are received by the receiving element S.
When received in S1, it is possible to detect that the position of the listener's head is at the position on the left speaker SL side of the headrest portion 90.

Although not shown, contrary to the case of FIG. 9B, the reflected wave from the listener's head of the ultrasonic wave transmitted from the super tweeter of the left speaker SL, that is, 40 kHz.
When the ultrasonic wave of z is received by the receiving element SS6 and the reflected wave from the listener's head of the ultrasonic wave transmitted from the super tweeter of the right speaker SR, that is, the ultrasonic wave of 50 kHz is received by the receiving element SS4. In addition, it is possible to detect that the position of the listener's head is at a position according to the right speaker SL side of the headrest portion 90.

Further, as shown in FIG. 9C, the reflected wave from the listener's head of the ultrasonic wave transmitted from the super tweeter of the left speaker SL, that is, the ultrasonic wave of 40 kHz is received by the receiving element SS3, and When the receiving element SS4 receives the reflected wave from the listener's head of the ultrasonic wave transmitted from the super tweeter of the right speaker SR, that is, the position of the listener's head is determined by the headrest part. It can be detected that it is at a position exactly in the middle of the left and right speakers SL, SR of 90.

As described above, which of the six receiving elements arrayed in the headrest 90 receives the ultrasonic waves of different frequencies transmitted from the super tweeters of the left and right speakers SL and SR. Depending on whether the head rest 90 is offset by the listener's head, the offset (deviation) can be detected.

Furthermore, by measuring the time from the transmission of the ultrasonic waves transmitted from the super tweeters of the left and right speakers to the reception by the receiving element, it is possible to determine the time depending on the time and the speed of the ultrasonic waves. The distance from the headrest portion 90 to the listener's head can be detected. The position of the listener's head with respect to the headrest portion 90 can be detected more accurately based on the offset of the listener's head with respect to the headrest portion 90 and the distance.

Then, the detecting section 40A detects the accurate position of the listener's head based on the detection output from each receiving element provided in the headrest section 90 in an array. That is, as described above, the detection unit 40A determines which of the receiving elements receives the ultrasonic waves transmitted from the super tweeters of the left and right speakers, and further the ultrasonic waves transmitted from the super tweeters of the left and right speakers. The position of the listener's head is detected in consideration of the time from transmission to reception.

The CPU 50 corresponds to the current position of the listener's head with respect to the headrest 90 from the detector 40A, as in the case of the CPU 50 of the sound processing apparatus 1 according to the first embodiment. The data is read from the database 60, and the read data (coefficient data,
Filter 2 for which the transaural system filter unit 20 uses function data or parameters)
1, 22, 23, 24.

As a result, the transaural system unit 20 performs a correction process on the audio signal after the sound image localization process according to the current position of the head of the listener with respect to the headrest unit 90, and the corrected audio signal. Are supplied to the left and right speakers SL, SR, and the headrest portion 90
On the other hand, even if the position of the listener's head changes, the sound image of the sound emitted from the left and right speakers can be localized at the virtual speaker position.

In the case of the sound processing devices 1, 2, 3, 4 of the above-described first to third embodiments, ultrasonic waves are used to detect the position of the listener's head. Since ultrasonic waves cannot be heard as sound by the human ear, the listener will not be aware that he or she is performing head detection processing.

In addition, since a normal music component does not include an ultrasonic wave component that affects detection accuracy (measurement accuracy), interference with a reproduced sound (music signal) for listening becomes a problem. There is no. That is, during the reproduction of music, it is possible to measure and detect the position of the listener with respect to the speaker without deteriorating the reproduced sound and without the listener being aware of it.

In the acoustic processing device 4 of the third embodiment described above, six ultrasonic wave receiving elements are provided in the headrest portion 90, but the number of ultrasonic wave receiving elements is not limited to this, and more ultrasonic waves can be transmitted. Of course, the receiving elements may be used, or a plurality of receiving elements may be provided in a plurality of rows. Further, it is possible to appropriately adjust the distance between the receiving elements and the orientation of the sound emitting surfaces of the left and right speakers SL and SR.

Further, the ultrasonic receiving element may be provided at any position where the reflection from the head of the listener can be received in addition to the headrest 90 and its vicinity.

Further, instead of the transaural system filter section 20, the simplified transaural system section 70 used in the modification of the first embodiment shown in FIG. 5 may be used. Instead of the 2-channel sound image localization processing filter section 10, a multi-channel, for example, 5-channel sound image localization processing filter 80 may be used.

Therefore, also in the case of the sound processing apparatus of the third embodiment described above, as in the case of the sound processing apparatus of the first and second embodiments described above, the headrest portion 9
The position of the listener's head with respect to 0 is measured constantly or at any time, and correction processing (transaural processing) according to the transfer function according to the measured position is performed, so that Avoiding a situation where the virtual speaker localization effect is insufficient due to an incorrect combination of the measurement position of the head and the listening position, and effects such as front localization of the sound image and all-around localization of the sound image without being influenced by the position of the listener's head. Can be realized.

[Fourth Embodiment] The first to third embodiments described above.
In the above embodiment, the position of the listener's head with respect to the headrest portion provided with the speaker is detected by transmitting ultrasonic waves and receiving the reflected waves. However, the position detection of the listener's head is not limited to that using ultrasonic waves.

For example, videophones capable of transmitting and receiving not only voice but also images have been used at home. Then, for example, as shown in FIG. 10, a so-called home theater system is provided by a TV set 200 and a chair equipped with an acoustic processing device having a headrest portion 30 provided with left and right two-channel speakers SR and SL. In the case of construction, a CCD camera 210 normally used for a videophone
Can be used to detect the position of the listener's head with respect to the headrest portion 30.

In addition, it is often the case that a voice such as music is heard inside the automobile (inside the vehicle). Therefore, as shown in FIG. 11, it is conceivable to configure a sound processing device by providing a headrest portion in which a left and right two-channel speaker (SL1, SR1 or SL2, SR2) is mounted on a seat in an automobile. In such a case, for example, by mounting the CCD camera 310 for the videophone in the automobile, the CCD camera 3 for the videophone can be mounted.
10 can be used to detect the position of the listener's head with respect to the headrest portion.

Even under the current circumstances, in some types of automobiles, a CCD camera is provided outside the automobile to eliminate blind spots and the like, and an image captured through the CCD camera is displayed on the display in the automobile. There is also provided a camera which can be viewed, and it is possible to mount a CCD camera for capturing an image inside the vehicle on the vehicle.

Therefore, in the sound processing apparatus of the fourth embodiment, the position of the listener's head with respect to the headrest portion provided with the speaker is set at home or in a car.
By using a CD camera (CCD device) to grasp in real time how much the listener's head is sitting with respect to the speaker, and using the transfer function suitable for that position in the system, more freedom is achieved. This allows the virtual speaker localization effect to be enjoyed in various postures.

The sound processing device 5 of the fourth embodiment can also process the left and right two-channel audio signals as in the case of the sound processing device 1 of the first embodiment described above. The sound image of the sound emitted from the left and right two-channel speakers provided in the headrest portion can be localized in the front direction of the listener. That is, the sound processing device 5 can localize the sound image as if the sound emitted from the left and right two-channel speakers provided in the headrest portion were emitted from the virtual speakers VSL and VSR.

FIG. 12 is a block diagram for explaining the sound processing device 5 of the fourth embodiment. This Figure 1
As described with reference to FIGS. 10 and 11, the sound processing device 5 shown in FIG. 2 is provided in a home room or an automobile. Then, the sound processing device 5 shown in FIG. 12 analyzes the CCD camera 210 and the image captured by the CCD camera 210, and image analysis for detecting the position of the listener's head with respect to the headrest portion 30. Except for the portion 40D, the configuration is similar to that of the acoustic processing device 1 of the first embodiment shown in FIG.

For this reason, in the sound processing device 5 of the fourth embodiment shown in FIG. 12, the parts configured in the same manner as the sound processing device 1 of the first embodiment shown in FIG. The same reference numerals are given and the description of those portions is omitted.

In the sound processing device 5 of the fourth embodiment, the CCD camera 210 is set so as to face the direction of the listener so that an image always in the direction of the listener can be picked up. There is. Then, the CCD camera 210, under the control of the CPU 50, for example, constantly captures an image in the direction of the listener while the acoustic processing device 5 is operating, or at every predetermined timing, and analyzes the captured image. Supply to the section 40D.

The image analysis section 40D includes a CCD camera 210.
The image data from the image is analyzed and the position of the listener's head with respect to the headrest portion 30 is detected.
Notify U50. Specifically, the position of the speaker of the headrest portion 30 can be confirmed by image processing by marking a predetermined position such as a chair on which the listener sits or a headrest portion of the seat.

Since the listener is always moving even while sitting on the chair, the edge part of the listener can be extracted by using this and taking the time-axis difference of the still image. . From the edge portion of the listener and the position of the speaker, the positional relationship between the listener's head and the speakers SL and SR of the headrest portion 30 can be known.

The CPU 50 reads the coefficient data stored in the database 60 based on the detection result (the position of the listener's head) from the image analysis section 40D, and the coefficient data stored in the database 60 corresponds to the transaural system filter section 20. Supply to the filter.

As a result, in the transaural system filter section 20, the sound signal subjected to the sound image localization processing is corrected in accordance with the position of the listener's head,
Even when the position of the listener's head with respect to the headrest portion 30 changes, the sound images of the sounds emitted from the left and right speakers SL and SR of the headrest portion 30 are emitted from the virtual speakers VSL and VSR. Can be localized as.

When analyzing the image picked up by the CCD camera 210, the case where the head moves in the vertical direction, which is the direction orthogonal to the head contact surface of the headrest portion 30, and the case where the headrest portion 30 moves When the head moves in the lateral direction which is the direction parallel to the head contact surface,
The latter lateral movement can be detected more easily.

Originally, the speaker was the headrest portion 30.
Therefore, even if the listener's head moves by the same amount, the head is moved in the vertical direction, which is the direction orthogonal to the head contact surface of the headrest portion 30, even if the listener's head moves by the same amount. When the head is moved in the horizontal direction, which is a direction parallel to the head contact surface of the headrest portion 30, when the head is moved, the speaker or the listener's ear is more moved in the horizontal direction. The change in the transfer function is significant.

Therefore, in the sound processing device 5 of the fourth embodiment, the lateral position (offset) of the listener's head is sensed by analyzing the image captured by the CDD camera 210. Accordingly, by using appropriate filter coefficients for each filter of the transaural system fill section 20, the sound image of the sound emitted from the left and right speakers SL, SR of the headrest 30 is accurately obtained. The position is localized.

Even in the sound processing device 5 of the fourth embodiment, the transaural system filter section 20 is replaced by a simple modification which is used in the modification of the first embodiment shown in FIG. It is also possible to use the mold transaural system unit 70. Also, 2
It is also possible to use a sound image localization processing filter 80 of multiple channels, for example, 5 channels instead of the sound image localization processing filter unit 10 of the channels.

Therefore, also in the case of the sound processing device of the fourth embodiment, as in the case of the sound processing devices of the above-described first, second, and third embodiments, listening to the headrest portion 30 is performed. The position of the person's head is always or
Virtual speaker localization due to inaccurate measurement of the listener's head and listening position by performing correction processing (trans-aural processing) according to the transfer function according to the measured position as needed. It is possible to avoid a state in which the effect is insufficient, and to realize effects such as localization of the front of the sound image and localization of the entire circumference of the sound image without being influenced by the position of the listener's head.

Incidentally, the above-mentioned first, second, and fourth
In the embodiment, the case where the sound emitting surface of the speaker provided in the headrest portion is parallel to the surface of the headrest portion in contact with the head is shown. Such as tilting towards the listener
It is also possible to make appropriate modifications.

Further, in the above-mentioned embodiment, the example in which the two speakers of the left speaker SL and the right speaker SR are provided in the headrest part is shown, but the number of speakers is not necessarily two. Alternatively, one may be provided, or a plurality of three or more may be provided. Needless to say, a so-called HiFi-oriented speaker device including a tweeter or the like can be used.

Further, by providing all of the sound processing devices shown in FIGS. 1, 5, 6, 8, and 12 on the headrest side, the headrest can be removed from the backrest. The headrest portion can be attached to the backrest portion of another chair for use.

Further, in the sound processing apparatus shown in FIGS. 1, 5, 6, 8 and 12, an adapter is constituted by each part other than the left and right speakers, and this adapter and the headrest part provided with the speaker. The sound processing device according to the present invention can be configured by the above. Also,
The sound processing device of the present invention can be configured by providing each part other than the left and right speakers SL and SR, for example, on the backrest part of the chair or on the side of the audio signal reproducing device.

[0171]

As described above, the position of the listener's head with respect to the speaker can be detected, and the sound image localization processed audio signal can be corrected according to the actual position of the listener's head. it can. As a result, the degree of freedom of the position of the listener's head with respect to the speaker is increased, and a highly reliable acoustic processing device that does not reduce the effect of sound image localization due to some movement of the listener's head is provided. be able to.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining a first embodiment of a sound processing device according to the present invention.

FIG. 2 is a diagram for explaining the appearance of a chair equipped with the sound processing device according to the first embodiment.

FIG. 3 is a diagram for explaining the principle of sound image localization processing performed in the acoustic processing apparatus according to the first embodiment shown in FIG.

FIG. 4 is a diagram for explaining a process of detecting the position of the listener's head, which is performed in the sound processing device of the first embodiment shown in FIG. 1.

FIG. 5 is a block diagram for explaining a modification of the sound processing device of the first embodiment shown in FIG.

FIG. 6 is a block diagram for explaining a second embodiment of the sound processing device according to the present invention.

FIG. 7 is a diagram for explaining the principle of sound image localization processing performed in the acoustic processing device of the second embodiment shown in FIG.

FIG. 8 is a block diagram for explaining a third embodiment of the sound processing device according to the present invention.

FIG. 9 is a diagram for explaining a process of detecting the position of the listener's head, which is performed in the sound processing device of the third embodiment shown in FIG.

FIG. 10 is a diagram for explaining an example of a usage mode of the sound processing device of the fourth embodiment according to the present invention.

FIG. 11 is a diagram for explaining another example of the usage mode of the sound processing device of the fourth embodiment according to the present invention.

FIG. 12 is a block diagram illustrating a sound processing device according to a fourth embodiment of the present invention.

[Explanation of symbols]

10 ... Sound image localization processing filter section, 11-14 ... Filter, 15, 16 ... Addition section, 20 ... Transaural system filter section, 21-24 ... Filter, 25, 26 ...
Adder, 30 ... Headrest, SL ... Left speaker, S
R ... right speaker, VSL ... virtual left speaker, VSR ... virtual right speaker, 40 ... head position detection unit, 50 ... CPU,
60 ... Database, 70 ... Simplified transaural system filter section, 41, 42 ... Filter, 80 ... Sound image localization processing filter section, 81-90 ... Filter, 91, 9
2 ... Adder, SS1 to SS6 ... Ultrasonic wave receiving element, 21
0, 310 ... CCD camera

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kenji Nakano             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F term (reference) 5B057 AA20 BA04 CA13 CB20 CH01                       DB03 DC02                 5D062 AA65                 5L096 AA09 BA20 FA69 LA11

Claims (5)

[Claims] 1. A speaker device, and a sound image localization processing unit that performs processing for locating a sound image of a sound by the sound signal at a predetermined position with respect to a sound signal to be supplied to the speaker device. A correction processing unit that performs correction processing on the audio signal from the sound image localization processing unit according to the position of the listener's head with respect to the speaker device; and the position of the listener's head with respect to the speaker device. A sound processing device, comprising: a head position detecting unit that detects the position, and a control unit that controls the correction processing unit according to a detection result from the head position detecting unit. 2. The sound processing device according to claim 1, wherein the head position detecting section includes ultrasonic wave transmitting means for transmitting ultrasonic waves, and the ultrasonic wave transmitting means for transmitting ultrasonic waves to the head of the listener. Ultrasonic receiving means for receiving the reflected ultrasonic waves reflected by the section, whether or not the reflected ultrasonic waves are received by the ultrasonic receiving means, and ultrasonic waves when the reflected ultrasonic waves are received by the ultrasonic receiving means. And a head position specifying means for specifying the position of the listener's head with respect to the speaker based on the speed and the time from the transmission of ultrasonic waves to the reception of reflected ultrasonic waves. Processing equipment. 3. The acoustic processing device according to claim 2, wherein the ultrasonic wave transmitting means and the ultrasonic wave receiving means are high frequency speakers of the speaker device. . 4. The acoustic processing device according to claim 2, wherein the ultrasonic wave transmitting means is a high frequency speaker of the left and right two-channel speaker device, and the ultrasonic wave receiving means is provided at a predetermined position. An acoustic processing device comprising a plurality of ultrasonic sensing elements arranged side by side, wherein ultrasonic waves of different frequencies are transmitted from each of the high frequency speakers of the left and right channels. 5. The sound processing apparatus according to claim 1, wherein the head position detecting unit captures an image including a head of a listener who listens to sound through the speaker device. A sound processing apparatus comprising: a means and an image analysis means for analyzing an image captured by the imaging means and detecting a position of the listener's head with respect to the speaker device.