JP4735920B2 - Sound processor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sound processing apparatus that is configured by, for example, a speaker provided on a chair or a headrest, and that emits sound from the rear side of a listener's head.
[0002]
[Prior art]
A chair provided with a speaker at 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, the speaker can be provided in the vicinity of the listener's ear by providing the speaker on the backrest portion of the chair or the headrest.
[0003]
As described above, by using a chair or a headrest provided with a speaker, high-quality sound is emitted in the vicinity of the listener's ear and provided to the listener. That is, an environment in which a listener can listen to high-quality sound through a speaker positioned in the vicinity of the listener's ear without using headphones or the like has been prepared.
[0004]
[Problems to be solved by the invention]
By the way, when a speaker is provided on the chair backrest or headrest, high-quality sound can be emitted in the vicinity of the listener's ear, but sound is emitted directly from the back of the listener's ear. For this reason, it is considered that the listener's consciousness is attracted to the back of the listener, and depending on the music to be listened, there may be a sense of incongruity or so-called listening fatigue.
[0005]
In addition, when a listener uses a chair or headrest provided with a speaker, the positional relationship between the speaker and the listener's ear varies depending on the use, and the listener or headrest is always provided under the same conditions. It is difficult to listen to the sound emitted from the speaker.
[0006]
However, the position of the listener's head is forcibly restricted so that the position of the listener's head (ear position) is always the same with respect to the speaker provided in the chair or headrest. Doing so is not preferable because it hinders the listener's feeling of relaxation. In addition, 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.
[0007]
In view of the above, for example, the present invention is a sound that is always in an appropriate state without any sense of incongruity even if the position of the listener's head (ear position) with respect to a speaker provided on a chair or headrest is not constant. It is an object of the present invention to provide a sound processing apparatus that enables listening to music.
[0008]
[Means for Solving the Problems]
  In order to solve the above problem, the sound processing apparatus according to the first aspect of the present invention provides:
  A speaker device;
  A sound image localization processing unit that performs processing to localize a sound image of the sound by the sound signal to a predetermined position with respect to the sound signal to be supplied to the speaker device;
  A correction processing unit configured to perform a correction process according to the position of the listener's head relative to the speaker device with respect to the audio signal from the sound image localization processing unit;
  Ultrasonic transmitting means for transmitting ultrasonic waves, ultrasonic receiving means for receiving reflected ultrasonic waves transmitted from the ultrasonic transmitting means and reflected by the listener's head, and reflected ultrasonic waves by the ultrasonic receiving means Of the listener, and when the reflected ultrasonic wave is received by the ultrasonic wave receiving means, based on the speed of the ultrasonic wave and the time from transmission of the ultrasonic wave until reception of the reflected ultrasonic wave, Head position specifying means for specifying the position of the head relative to the speaker.A head position detector;
  A control unit configured to control the correction processing unit in accordance with a detection result from the head position detection unit;
  With,
  The ultrasonic transmission means and the ultrasonic reception means are high-frequency speakers of the speaker device.It is characterized by that.
[0009]
According to the acoustic processing apparatus of the first aspect, the sound signal supplied to the speaker device is processed by the sound image localization processing unit so that the sound image of the reproduced sound by the sound signal is localized at a predetermined position. Thereafter, correction processing 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. The
[0010]
The head position detector detects the actual position of the listener's head relative to the speaker device. Based on the detection result, the correction processing unit is controlled by the control unit, and the correction processing unit performs correction processing according to the position of the listener's head on the sound signal after the sound image localization processing.
[0011]
As a result, even when the positional relationship between the speaker device and the listener's head changes, the sound of the processed sound signal is satisfactorily listened without reducing the effect of sound image localization performed on the sound signal. To be able to.
[0013]
  AlsoThis claim1According to the acoustic processing device described in (4), the presence or absence of reflected ultrasonic waves and the time until the ultrasonic waves transmitted from the ultrasonic transmission means are reflected by the listener's head and received by the ultrasonic reception means. Then, the position of the listener's head relative to the speaker device is specified by the head position specifying means based on the ultrasonic velocity, and correction processing is performed by the control unit in accordance with the specified position of the listener's head Part is controlled.
[0014]
Thus, by using the ultrasonic transmission means and the ultrasonic reception means provided at a specific position with respect to the speaker device, the speaker device and the head of the listener who listens to the sound using the speaker device, The positional relationship is reliably and accurately detected, and based on this, the correction processing in the correction processing unit can be appropriately controlled.
[0016]
  AlsoThis claim1According to the acoustic processing apparatus described in the above, the ultrasonic transmission means and the ultrasonic reception means for detecting the positional relationship between the speaker device and the position of the listener's head are high-frequency speakers of the speaker device. . That is, the high frequency range speaker itself is used for the ultrasonic transmission means and the ultrasonic reception means.
[0017]
Thus, in order to detect the positional relationship between the speaker device and the listener's head, the ultrasonic transmission means is not necessary to newly provide an ultrasonic transmission means and an ultrasonic reception means, and the existing high-frequency speaker is an ultrasonic transmission means, It can be used as an ultrasonic wave receiving means to detect the relationship between the speaker device and the listener's head.
[0018]
  Claims2The sound processing apparatus described in
  A speaker device;
  A sound image localization processing unit that performs processing to localize a sound image of the sound by the sound signal to a predetermined position with respect to the sound signal to be supplied to the speaker device;
  A correction processing unit configured to perform a correction process according to the position of the listener's head relative to the speaker device with respect to the audio signal from the sound image localization processing unit;
  Ultrasonic transmitting means for transmitting ultrasonic waves, ultrasonic receiving means for receiving reflected ultrasonic waves transmitted from the ultrasonic transmitting means and reflected by the listener's head, and reflected ultrasonic waves by the ultrasonic receiving means Of the listener, and when the reflected ultrasonic wave is received by the ultrasonic wave receiving means, based on the speed of the ultrasonic wave and the time from transmission of the ultrasonic wave until reception of the reflected ultrasonic wave, A head position detection unit comprising head position specifying means for specifying the position of the head relative to the speaker;
  A control unit configured to control the correction processing unit according to a detection result from the head position detection unit;
  With
  The ultrasonic transmission means is a high-frequency speaker of the speaker device with two channels on the left and right,
  The ultrasonic receiving means comprises a plurality of ultrasonic sensing elements arranged in a predetermined position,
  Ultrasonic waves having different frequencies are transmitted from the high-frequency speakers of the two left and right channels.
[0019]
  This claim2According to the acoustic processing apparatus described in the above, the high frequency range speaker of the left and right channel speaker device is used as the ultrasonic transmission unit, and a plurality of ultrasonic reception units are arranged in the vicinity of the ultrasonic transmission unit, for example. An ultrasonic sensing element having a so-called array structure is used.
[0020]
Also, consider the ultrasonic sensing element that senses the reflected ultrasonic waves reflected from the head of the listener of the ultrasonic waves that are transmitted from each of the high-frequency speakers of the left and right channels. Thus, the positional relationship between the speaker device and the listener's head can be detected more accurately.
[0021]
  Also,In the sound processing apparatus according to another embodiment of the present invention,The head position detection unit is configured to capture an image including a head of a listener who is listening to sound through the speaker device, and to analyze the image captured by the imaging unit, And image analysis means for detecting the position of the head relative to the speaker device.
[0022]
  Thissound ofAccording to the sound processing apparatus, an image including the head of the listener at a position where the sound is heard through the speaker device is captured by the imaging unit, and the captured image is analyzed by the image analysis unit, and the speaker device The positional relationship with the listener's head is detected.
[0023]
Accordingly, the positional relationship between the speaker device and the listener's head is accurately detected based on the image including the listener's head at the position where the sound is heard through the speaker device, and the correction processing unit is accordingly detected. It is possible to appropriately control the correction process in the above.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a sound processing apparatus according to the present invention will be described with reference to the drawings. In the embodiment described below, for example, a sound processing device configured by mounting a speaker on a headrest portion (head support portion) provided in a car seat or a headrest portion of a chair used at home is taken as an example. explain.
[0025]
[First Embodiment]
FIG. 1 is a block diagram for explaining a sound processing apparatus 1 according to a first embodiment to which the present invention is applied, and FIG. 2 is equipped with the sound processing apparatus according to the first embodiment. It is a figure for demonstrating the external appearance of a chair. The sound processing apparatus 1 according to the first embodiment can process left and right two-channel audio signals.
[0026]
In FIG. 1, a disc 100 provides a 2-channel audio signal (2-channel sound source (ch is an abbreviation for channel)). The left and right channel audio signals reproduced from the disc 100 are supplied to the acoustic processing apparatus 1 of the first embodiment shown in FIG.
[0027]
Therefore, as shown in FIG. 1, the sound processing apparatus 1 according to the first embodiment includes a left channel input terminal Lin that receives supply of a left channel audio signal from the disc 100 that is a 2ch sound source, and a right channel. And a right channel input terminal Rin for receiving the supply of the audio signal.
[0028]
As shown in FIG. 1, the sound processing apparatus 1 according to the first embodiment includes a sound image localization processing filter unit 10, a trans-oral system filter unit 20, a headrest unit 30, a head position detection unit ( Hereinafter, it includes a detection unit 40, a CPU (Central Processing Unit) 50, and a coefficient database (hereinafter simply referred to as a database) 60 for the trans-oral system filter unit 20.
[0029]
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 support portion) that supports the user's head in a car seat or a chair used at home.
[0030]
That is, as shown in FIG. 2, a so-called chair St such as a car seat or a reclining seat is roughly divided into a seat part St <b> 1 that is a part where the user sits down, and a backrest that is a part that rests the user's back. It comprises a part St2 and a headrest part St3 which is a part that supports the user's head.
[0031]
In the first embodiment, the headrest portion 30 shown in FIG. 1 is configured 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. Yes. Therefore, a listener (user) who sits down on the chair provided with the headrest portion 30 listens to sound emitted from the left speaker SL and the right speaker SR located obliquely behind his / her head. become.
[0032]
The headrest part may be removable such as an automobile seat, while the headrest part may be formed integrally with the backrest part, and only the headrest part cannot be removed. In the latter case, it can also be said that a speaker is provided on the backrest of the chair. In the first embodiment, the headrest portion 30 can be removed from the backrest portion of the chair, for example.
[0033]
In the sound processing apparatus 1 according to the first embodiment, the sound is transmitted to the listener by shifting the sound localization from the position of the actually fixed speaker to the position of the virtual speaker. Discomfort and discomfort caused by hearing from the back of the head or behind the listener's ears are removed.
[0034]
That is, in the first embodiment, the sound emitted from the left speaker SL and the right speaker SR of the headrest unit 30 by the sound image localization processing filter unit 10 and the trans-oral system filter unit 20 is shown in FIG. In FIG. 2, the sound is heard as if sound is emitted from the positions of the left virtual speaker VSL and the right virtual speaker VSR indicated by dotted lines. In other words, the sound image of the sound emitted from the real speakers SL and SR is localized so that it feels like the sound emitted from the virtual speakers VSL and VSR.
[0035]
In the first embodiment, the virtual speakers VSL and VSR are virtual positions that localize the sound emitted from the left speaker SL and the right speaker SR, as shown in FIG. 1 and FIG. In addition, when the listener's head with respect to the headrest portion 30 is in a predetermined position, the listener's head is set to a predetermined position in the forward direction of the listener.
[0036]
As described above, the sound emitted from the left speaker SL and the right speaker SR of the headrest unit 30 is localized as if it was emitted from the positions indicated by the left and right virtual speakers VSL and VSR, as described above. Therefore, it is possible to eliminate the uncomfortable feeling and discomfort caused by the sound being heard near the back of the listener's head or behind the listener's ear so that the listener can listen to the sound as a natural sound.
[0037]
Hereinafter, each part of the sound processing apparatus according to the first embodiment will be described in detail. First, in describing 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.
[0038]
As shown in FIG. 3, in a predetermined reproduction sound field, the position of the dummy head DH is set as the position of the listener, and the left and right virtual speakers that attempt to localize the sound image with respect to the listener at the position of the dummy head DH The actual left speaker SPL and the actual right speaker SLR are actually installed at the position (the position where the speaker is supposed to be).
[0039]
Then, the sound emitted from the left actual speaker SPL and the right actual speaker SPR is collected at both ears of the dummy head DH, and the sound emitted from the left actual speaker SPL and the right actual speaker SPR is collected by the dummy head DH. A transfer function (HRTF) indicating how it changes when reaching both ears is measured in advance.
[0040]
As shown in FIG. 3, in this first embodiment, the transfer function of the sound from the left real speaker SPL to the left ear of the dummy head DH is M11, and the right ear of the dummy head DH from the left real speaker SPL. It is assumed that the transfer function of the sound up to is M12. Similarly, the transfer function of the sound from the right real speaker SPR to the left ear of the dummy head DH is M21, and the transfer function of the sound from the right real speaker SPR to the right ear of the dummy head DH is M22.
[0041]
Then, as described above with respect to the headrest unit 30 in FIG. 1, the audio signal of the sound emitted from the speakers SL and SR of the headrest unit 30 that will be located in the vicinity of the listener's ear is previously set as described above. Processing is performed using the measured transfer function, and the sound of the processed sound signal is emitted.
[0042]
As a result, the sound emitted from the speakers SL and SR of the headrest unit 30 is heard as if the sound is emitted from the virtual speaker position (the positions of the virtual speakers VSL and VSR in FIGS. 1 and 2). The sound image of the sound emitted from the speakers SL and SR can be localized so that a person can feel.
[0043]
Here, the description has been made assuming that the dummy head DH is used when measuring the transfer function (HRTF), but the present invention is not limited to this. Of course, in a reproduction sound field for measuring a transfer function, a person is actually seated and a microphone is placed in the vicinity of the ear of the person to measure the transfer function of the sound.
[0044]
In this way, the sound image localization processing filter unit 10 shown in FIG. 1 is the part that performs the processing based on the transfer function of the sound that is measured in advance in order to localize the sound image at a 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 It consists of the addition units 15 and 16.
[0045]
The filter 11 processes the audio signal of the left channel supplied through the left input terminal Lin with the transfer function M11, and supplies the processed audio signal to the adder 15 for the left channel. The filter 12 processes the audio signal of the left channel supplied through the left input terminal Lin with the transfer function M12, and supplies the processed audio signal to the adding unit 16 for the right channel.
[0046]
The filter 21 processes the right channel audio signal supplied through the right input terminal Rin with the transfer function M21, and supplies the processed audio signal to the left channel adder 15. 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 adder 16.
[0047]
As a result, the sound based on the output audio signal from the left channel adder 15 and the sound based on the output sound signal from the right channel adder 16 are the left virtual speaker VSL and the right virtual speaker in FIGS. The sound image is localized so that sound is emitted from the VSR.
[0048]
However, even if the sound emitted from the left speaker SL and the right speaker SR provided in the headrest unit 30 is subjected to sound image localization processing, as shown in FIG. 1, the transfer function G11 in the actual reproduction sound field is shown. Under the influence of G12, G21, and G22, the sound image of the reproduced sound may not be accurately localized at the target virtual speaker position.
[0049]
Therefore, in the first embodiment, the transoral system filter unit 20 is used to perform correction processing on the audio signal from the sound image localization processing filter unit 10 so that the left speaker SL, the right speaker The sound emitted from the speaker SR is localized as if the sound was accurately emitted from the left and right virtual speakers VSL and VSR at the virtual speaker position.
[0050]
The trans-oral system filter unit 20 is an audio filter formed by applying a trans-oral system. The trans-oral system is a technique for realizing the same effect as that of the binaural system system, which is a system for strictly reproducing sound using headphones, even when a speaker is used.
[0051]
The transoral system will be described by taking the case of FIG. 1 as an example. With respect to the sound emitted from the left speaker SL and the right speaker SR, the sound emitted from each speaker to the left and right ears of the listener. By removing the influence of the transfer functions G11, G12, G13, and G14, the sound emitted from the left speaker SL and the right speaker SR is strictly reproduced.
[0052]
Therefore, the trans-oral system filter unit 20 shown in FIG. 1 removes the influence of the transfer function in the reproduction sound field for the sound to be emitted from the left speaker SL and the right speaker SR, so that the left speaker SL, The sound image of the sound emitted from the right speaker SR is accurately localized at a position corresponding to the virtual speaker position.
[0053]
Specifically, the transoral system filter unit 20 transmits signals from the right speaker SR to the listener's left and right ears in order to eliminate the influence of the transfer function from the left speaker SL and the right speaker SR to the listener's left and right ears. Filters 21, 22, 23, and 24 that process audio signals in accordance with the inverse function of the function, and addition units 25 and 26 are provided. In the first embodiment, the filters 21, 22, 23, and 24 perform processing that also takes into account the inverse filter characteristics so that more natural reproduced sound can be emitted.
[0054]
Further, as will be described in detail later, the transfer functions from the left speaker SL and right speaker SR to the left and right ears of the listener depend on the positions of the left and right speakers SL and SR and the listener's head (the ears of the listener's ears). The position will change. For this reason, in each of the filters 21, 22, 23, and 24 of the trans-oral system filter unit 20, the filter coefficient for each filter corresponding to the position of the listener's head stored in advance in the database 60 is transmitted through the CPU 50. It can be set.
[0055]
The output audio signal from the left channel adding unit 15 of the sound image localization processing filter unit 10 is supplied to the left channel filter 21 and the right channel filter 22 of the transoral system filter unit 20, and The output audio signal from the right channel adding 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 transoral system filter unit 20.
[0056]
Each of the filters 21, 22, 23, 24 performs a predetermined process using the filter coefficient from the CPU 50, and specifically, as described above, the current state of the listener from the speakers SL, SR. The speech signal supplied to the own filter is processed using inverse functions H1n, H2n, H3n, and H4n of transfer functions corresponding to the position of the head.
[0057]
In addition, in the inverse functions H1n, H2n, H3n, and H4n of transfer functions used in the filters 21, 22, 23, and 24, n means a variable that depends on the position of the listener's head, and other than n The characters H1, H2, H3, and H4 indicate functions that are used in the filters 21, 22, 23, and 24, respectively.
[0058]
The output from the filter 21 is supplied to the left channel adder 25, and the output from the filter 22 is supplied to the right channel adder 26. 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.
[0059]
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 supplies the audio signal to the right speaker SR. . Thereby, the sound emitted from the speakers SL and SR of the headrest unit 30 is removed from the influence of the transfer function according to the current position of the listener's head in the reproduction sound field, and the sound image is accurately left virtual. The sound can be localized like the sound emitted from the speaker VSL and the right virtual speaker VSR.
[0060]
As described above, in the sound processing device 1 according to the first embodiment, a listener whose head is located at a predetermined position in the vicinity of the headrest unit 30 emits sound from the speakers SL and SR of the headrest unit 30. The sound can be heard as if it was emitted from the virtual speakers VSL and VSR.
[0061]
Accordingly, the sound can be heard from the front of the listener despite listening to the sound emitted from the left speaker SL and the right speaker SR located obliquely behind the listener's head. Therefore, it is possible to listen to the sound satisfactorily without feeling uncomfortable or uncomfortable feeling that the sound emitted from the left speaker SL and the right speaker SR is stuck on the back side of the listener.
[0062]
However, as described above, in the case of the sound processing apparatus 1 shown in FIG. 1, the positional relationship from the virtual speaker position indicated by the virtual speakers VSL and VSR to both ears of the listener, and the speakers SL and SR to the listener. If the positional relationship between the two ears changes greatly between the transfer function measurement and the system playback (when actually playing back and listening to the sound), each transfer function also changes. The effect of localization of the sound image on the speaker position is diminished.
[0063]
In the case of the sound processing apparatus 1 of the first embodiment, as shown in FIG. 1, transfer functions from the speakers SL and SL of the headrest 30 to the ears of the listener are transfer functions G11, G12, and G21. , When the listener's head is at the position G22, the listener listens to the sound emitted from the speakers SL, SR of the headrest unit 30 as if the sound was emitted from the virtual speakers VSL, VSR. can do.
[0064]
However, if the position of the listener's head relative to the speakers SL and SR of the headrest unit 30 deviates from the assumed position, the sound image of the sound emitted from the speakers SL and SR is localized at the virtual speaker position. The virtual speaker localization effect cannot be obtained sufficiently.
[0065]
In particular, if the listener's head moves in a direction orthogonal to the sound emitting surface of the speaker (if it has moved in the vertical or horizontal direction parallel to the sound emitting surface of the speaker) The effect is larger than when moving closer or away from the speaker.
[0066]
For this reason, 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 predetermined position to listen to the sound, It is desirable to measure the transfer function at the position of the head and reproduce the sound with a system through a transfer function or inverse filter suitable for the position.
[0067]
However, it is difficult to always keep the position of the head of the listener sitting on the chair having the headrest 30 at a predetermined position with respect to the speaker. Moreover, even if it can be held, it may also hinder the listener's feeling of relaxation.
[0068]
Therefore, in the sound processing device 1 according to the first embodiment, when the sound processing device 1 is in the operating state, for example, at a predetermined timing, the distance and position from the headrest portion 30 to the listener's head. After the sound image localization processing is performed according to the latest position of the listener's head by supplying the filter coefficient corresponding to the measured position of the listener's head to each filter of the transoral system filter unit 20. Correction processing is performed on the audio signal.
[0069]
By doing so, even when the listener's head moves and the position of the listener's head has changed with respect to the headrest 30, that is, the speakers SL and SR, the virtual speaker position is obtained. The virtual speaker localization effect for localizing the sound image is not deteriorated, and the sound from the left and right speakers SL and SR of the headrest unit 30 can be heard in a more free posture.
[0070]
In the sound processing apparatus 1 according to the first embodiment, the super tweeter of the speaker mounted on the headrest unit 30 is used as a position detection sensor for the listener's head. In recent years, high-fidelity playback audio has progressed, and it is not uncommon to mount a speaker having a playback performance of an audible frequency band or higher, so this is used.
[0071]
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 higher than the audible frequency, and the speaker (speaker device) having this configuration is used by the listener. By using it for the measurement of the position of the head, it is configured so that it is not necessary to mount a dedicated sensor system such as a pressure-sensitive type.
[0072]
Then, ultrasonic waves of a predetermined frequency are transmitted from the super tweeters of the speakers SL and SR of the headrest unit 30, and the reflection of the ultrasonic waves mainly from the head is reflected on the super tweeters of the speakers SR and SL of the headrest unit 30. The presence or absence of reception of the reflected wave of the ultrasonic wave, and when the reflected wave is received, the time taken from the transmission of the ultrasonic wave to reception of the reflected wave, the time and the ultrasonic wave The position of the listener's head relative to the headrest 30 is detected based on the distance between the speaker and the listener obtained from the speed.
[0073]
FIG. 4 is a diagram for explaining the detection process of the position of the listener's head performed in the sound processing apparatus 1 of the first embodiment. As shown in FIG. 4, 40 kHz ultrasonic waves are transmitted from the super tweeters of the left and right speakers SL and SR of the headrest unit 30, and the reflected waves from the user's head are also transmitted to the left and right headrest units 30. Are received by the super tweeters of the speakers SL and SR.
[0074]
Control of transmission of ultrasonic waves from the super tweeters of the left and right speakers SL and SR is controlled by the CPU 50, for example. Then, the ultrasonic waves received by the super tweeters of the left and right speakers SL and SR are supplied to the detection unit 40. When detecting 40 kHz ultrasonic waves (reflected waves), or when receiving 40 kHz ultrasonic waves (reflected waves), the detection unit 40 determines the time it takes to transmit and receive the ultrasonic waves, the speed of the ultrasonic waves, and the like. The position of the listener's head with respect to the left and right speakers SL and SR of the headrest unit 30 is detected.
[0075]
That is, as shown in FIGS. 4A and 4B, when each of the super tweeters of the speakers SL and SR of the headrest unit 30 similarly receives the reflected ultrasonic wave transmitted, from transmission to reception. The position of the listener's head with respect to the headrest portion 30 can be detected according to the time taken for.
[0076]
Simply put, for example, as shown in FIG. 4A, when the time taken from transmission to reception of ultrasonic waves is relatively long, the listener's head is relatively separated from the headrest portion 30. It can be seen that it is located at the position. Further, as shown in FIG. 4B, when the time taken from transmission to reception of the ultrasonic wave is relatively short, the position of the listener's head is positioned relatively close to the headrest 30. You can see that
[0077]
Further, as shown in FIG. 4C, for example, only the super tweeter of the left speaker SL receives ultrasonic waves transmitted in the same way from the super tweeters of the left and right speakers SL and SR provided in the headrest unit 30, and the super speaker of the right speaker SR. When the tweeter does not receive the 40 kHz ultrasonic wave, it can be seen that the listener's head is offset to the left with respect to the headrest 30.
[0078]
Conversely, for example, only the super tweeter of the right speaker SR receives ultrasonic waves transmitted in the same way from the super tweeters of the left and right speakers SL and SR provided in the headrest unit 30, and the super tweeter of the left speaker SL exceeds 40 kHz. When the sound wave is not received, it is understood that the listener's head is offset to the right side with respect to the headrest portion 30.
[0079]
As described above, the detection unit 40 determines the distance from the speakers SL and SR of the headrest unit 30 and the left and right offsets (shift amount) based on the reflected waves from the heads of the listeners of the ultrasonic waves transmitted from the left and right speakers. ) Etc. can be sensed. In this case, the position of the listener's head is detected, for example, as a deviation (offset) from the reference position where the listener's head should originally be located, and this is notified to the CPU 50.
[0080]
Then, the CPU 50 refers to the database 60 based on the detection result of the position of the listener's head from the detection unit 40, and each of the trans-oral system filter units 20 according to the current position of the listener's head. The coefficient data supplied to the filters 21 to 24 is read out.
[0081]
In the first embodiment, the database 60 includes coefficient data supplied to each of the filters 21, 22, 23, and 24 of the transoral system filter unit 20, and the listener's head for the headrest unit 30. Data corresponding to the position of is stored.
[0082]
That is, the transfer function of the sound emitted from the speakers SL and SR of the headrest unit 30 to the left and right ears of the listener is measured in advance by changing the position of the listener's head relative to the headrest unit 30 in advance. Based on this measurement result, coefficient data used in each filter 21, 22, 23, 24 of the trans-oral system filter unit 20 is obtained, and the obtained coefficient data is associated with the position of the listener's head. Is stored in the database 60.
[0083]
Accordingly, in the database 60, the position of the listener's head is the coefficient data used in each of the filters 21, 22, 23, and 24 of the transoral system filter unit 20 at the position A, and the transoral system filter unit at the position B. The coefficient data used in each of the twenty filters 21, 22, 23, 34,..., And so on, the filters 21, 22, at each position of the listener's head whose position is changed with respect to the headrest 30. Coefficient data used in 23 and 24 is stored.
[0084]
Based on the detection result of the current position of the user's head from the detection unit 40, the CPU 50 reads coefficient data to be supplied to each filter 21, 22, 23, 24 of the transoral system filter unit 20 from the database 60. This is supplied to the corresponding filter of the trans-oral system filter unit 20.
[0085]
As a result, even if the position of the listener's head moves relative to the headrest portion 30, the actual position of the listener's head is measured, and the effect of the transfer function in the reproduction sound field is removed according to the position. As described above, the transoral system filter unit 20 can perform correction processing. Therefore, the sound image of the sound emitted from the left and right speakers SL and SR of the headrest unit 30 can be localized at the virtual speaker position regardless of the position of the listener's head.
[0086]
In the first embodiment, the database 60 obtains a function to be set for each filter at each position of the head based on the transfer function measured at each position that the listener's head can take. The function and the position of the head may be stored in association with each other. That is, the function itself used for correction may be stored in a database in association with the position of the head, and set in the target filter of the transoral system filter unit.
[0087]
Further, as in the case of the first embodiment described above, for example, a transfer function at a reference position is measured, and necessary parameters such as an amplitude adjustment parameter and a delay processing parameter for the reference transfer function are set. Alternatively, based on the reference parameter, a new parameter may be obtained according to the actual position of the detected listener's head and set in each filter.
[0088]
That is, by setting one transfer function model and adjusting the model according to the position of the listener's head, a correction process according to the actual position of the listener's head is performed. It is also possible to perform it on an audio signal. In this case, when the parameter placed at the reference position is held as a reference model in, for example, a program executed by the CPU, a memory for holding the parameter is not necessary, and only the reference parameter is stored in the memory. Therefore, a large memory capacity is not necessary.
[0089]
As described above, the processing information stored in the database 60 and supplied to each filter of the trans-oral system filter unit 20 includes a plurality of types such as coefficient data, function data, and parameter data. However, these may be used according to each filter circuit to be actually mounted on the sound processing apparatus.
[0090]
The database 60 is a semiconductor memory such as a ROM or an EEPROM, for example. The database 60 may be a recording medium such as a magnetic disk, an optical disk, or a magneto-optical disk.
[0091]
[Modification of First Embodiment]
FIG. 5 is a block diagram for explaining a modification of the sound processing apparatus according to the first embodiment. As shown in FIG. 5, the sound processing device 2 of this example is the first illustrated in FIG. 1 except that a simplified transoral system filter unit 70 is mounted instead of the transoral system filter unit 20. It is comprised similarly to the acoustic processing apparatus 1 of embodiment. Therefore, in the sound processing device 2 shown in FIG. 5, the same reference numerals are given to the same parts as those of the first sound processing device 1 shown in FIG. 1, and the detailed description thereof is omitted. .
[0092]
As shown in FIGS. 1, 2, and 5, the headrest 30 and the listener's head are usually close to each other, and the speakers SL and SR of the headrest 3 are close to the listener's ears. The crosstalk component from the speakers SL and SR to the ear on the opposite side is much smaller than the audio signal component from the speakers SL and SR to the ear on the side corresponding to the speaker.
[0093]
That is, in the example shown in FIG. 1, since the transfer functions G12 and G21 of the crosstalk component are much smaller than the transfer functions G11 and G22, the transfer functions G12 and G21 of the crosstalk component can be ignored. For this reason, the simplified transoral system filter unit 70 shown in FIG. 5 is simplified by omitting consideration of the crosstalk component from the normal transoral system.
[0094]
As shown in FIG. 5, the simplified transoral system filter unit 70 includes a filter 71 that processes an audio signal with an inverse function of an audio transfer function G1 from the left speaker SL of the headrest unit 30 to the left ear of the listener. And a filter 72 that processes the 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 experimentally confirmed that the sound localization is the virtual speaker position even when the crosstalk component is ignored.
[0095]
Each of the two filters 71 and 72 of the simplified transoral system filter unit 70 actually has a function according to the actual position of the listener's head in the reproduction sound field, as will be described later. Alternatively, coefficient data is set.
[0096]
In this case, since the data prepared in the database 60 need only be for the filters 71 and 72, the amount of data stored in the database 60 can be reduced. Accordingly, a database 60 having a small storage capacity can be used.
[0097]
In the case of the sound processing apparatus 2 shown in FIG. 5, the configuration of the sound processing apparatus can be simplified by using the simplified transoral system filter unit 70.
[0098]
Further, in the case of the sound processing apparatus shown in FIG. 5 as well, as in the case of the sound processing apparatus 1 of the first embodiment shown in FIG. 1, the left located on the diagonally rear side of the listener's head. Despite listening to the sound emitted from the speaker SL and the right speaker SR, the sound is heard from the front of the listener, so the sound emitted from the left speaker SL and the right speaker SR. Can be heard well without feeling uncomfortable or uncomfortable, such as being stuck to the back of the listener.
[0099]
[Second Embodiment]
FIG. 6 is a block diagram for explaining the sound processing apparatus 3 according to the second embodiment to which the present invention is applied. The acoustic processing apparatus according to the second embodiment can process an audio signal from a multi-channel medium such as a DVD. In the second embodiment, a 5-channel audio signal is used. Can be processed.
[0100]
As shown in FIG. 6, the sound processing device 3 according to the second embodiment includes audio signal input terminals i1 to i5 for five channels, for example, five channels from a multichannel recording medium such as a DVD. Minute audio signals can be received. 6 includes a headrest unit 30, a head position detection unit 40, a CPU 50, a database 60, a simplified transoral system filter unit 70, and a sound image localization processing filter unit 80.
[0101]
The headrest unit 30 is the same as the headrest unit 30 of the sound processing device 1 of the first embodiment shown in FIG. 1 and the sound processing device 2 of the modification of the first embodiment shown in FIG. It is configured. The simplified trans-oral system filter unit 70 is configured in the same manner as the simplified trans-oral system filter unit 70 of the sound processing apparatus 2 according to the modification of the first embodiment described above with reference to FIG. is there.
[0102]
The sound image localization processing filter unit 80 of the acoustic processing device 3 according to the second embodiment is basically based on the same principle as the sound image localization processing filter unit 10 of the acoustic processing device according to the first embodiment. Based on this, the sound image of the sound emitted from the speaker is localized.
[0103]
However, in the acoustic processing apparatus according to the second embodiment shown in FIG. 6, the sound images of the sounds emitted from the left and right speakers SL and SR of the headrest 30 are shown in FIG. Localization is performed so that sound is emitted from the virtual speakers VS1 to VS5.
[0104]
FIG. 7 is a diagram for explaining the principle of the sound image localization processing filter unit 80 of the acoustic processing device 3 according to 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 (in 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 the speakers are assumed to be). Then, a transfer function (HRTF) to the left and right ears of the dummy head DH of the sound emitted from each of the real speakers SP1 to SP5 is measured in advance.
[0105]
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 sound from the real speaker SP1 to the right ear of the dummy head DH. The transfer function is N12. The transfer function of the sound from the real speaker SP2 to the left ear of the dummy head DH is N21, and the transfer function of the sound from the real speaker SP2 to the right ear of the dummy head DH is N22.
[0106]
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, respectively, and the transfer function of the sound from the real speaker SP4 to the left and right ears of the dummy head DH is 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.
[0107]
Then, as described with reference to FIG. 7, the audio signal input from each of the input terminals i1 to i5 is processed using the corresponding transfer function measured in advance, and the simplified transoral system filter unit 70 The correction process is performed, and the sound based on the processed sound signal is supplied to the left and right speakers SL and SR of the headrest unit 30, and the sound is emitted.
[0108]
As a result, the sound emitted from the speakers SL and SR of the headrest 30 is felt as if the viewer feels as if the sound is emitted from the positions indicated by the virtual speakers VS1 to VS5 indicated by dotted lines in FIG. Sound image can be localized.
[0109]
In this way, in order to localize the sound image, the part that performs processing based on the sound transfer function 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 according to this embodiment can process a 5-channel audio signal, and includes ten filters 81 to 90 and two addition units 91 and 92. It consists of
[0110]
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 supplies the processed audio signal to the right channel adder 92.
[0111]
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 supplies the processed audio signal to the right channel adder 92.
[0112]
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. Further, the filter 86 processes the audio signal supplied through the terminal i3 with the transfer function N32, and supplies the processed audio signal to the right channel adding unit 92.
[0113]
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 supplies the processed audio signal to the right channel adding unit 92.
[0114]
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 supplies the processed audio signal to the right channel adding unit 92.
[0115]
Thereby, the sound based on the output sound signal from the left channel adder 91 and the sound based on the output sound signal from the right channel adder 92 are the positions of the virtual speakers VS1 to VS5 indicated by dotted lines in FIG. The sound image is localized so that sound is emitted from the sound source.
[0116]
And also in the case of the sound processing apparatus 3 of this 2nd Embodiment, the left speaker SL provided in the headrest part 30, right like the case of the sound processing apparatuses 1 and 2 of 1st Embodiment. Even if the sound emitted from the speaker SR is subjected to sound image localization processing, the sound image of the reproduced sound can be localized at the target virtual speaker position under the influence of the transfer function in the actual reproduced sound field. It may be impossible.
[0117]
Therefore, also in the sound processing device 3 of the second embodiment, sound is emitted from the left and right speakers SL and SR of the headrest unit 30 by using the simplified transoral system filter unit 70 that does not consider the crosstalk component. The sound image of the sound to be performed is accurately localized at each position of each virtual speaker VS1 to VS5.
[0118]
As described above, media having a multi-channel sound source such as a DVD have become widespread. However, as in the sound processing device 3 of the second embodiment, it is possible to process a 5-channel audio signal. Thus, a virtual five-channel sound image can be obtained through the two speakers SL and SR of the headrest unit 30 to enjoy powerful reproduced sound.
[0119]
Further, even when the position of the listener's head relative to the headrest portion 30 is changed due to the movement of the listener's head, the case of the sound processing apparatuses 1 and 2 according to the first embodiment described above. Similarly, by detecting the position of the listener's head relative to the headrest unit 30 and changing the functions and parameters of the filters 71 and 72 of the simplified transoral system filter unit 70 according to the position, The sound emitted from the left and right speakers SL and SR can be localized at the virtual speaker position.
[0120]
That is, also in the second embodiment, ultrasonic waves are transmitted from the super tweeters of the left and right speakers SL and SR of the headrest unit 30 as in the case of the sound processing apparatuses 1 and 2 of the first embodiment. Then, the super tweeter receives the reflected wave from the head of the listener of the transmitted ultrasonic wave, and based on this, the detection unit 40 detects the position of the head of the listener and the transfer function at that position is detected. The sound image can be localized at a predetermined virtual speaker position by performing correction processing in the simple transoral system filter unit 70 so as to remove the influence.
[0121]
In the second embodiment, the simplified transoral system filter unit 70 is used. However, as in the case of the sound processing apparatus 1 of the first embodiment shown in FIG. A trans-oral system filter 20 that also considers the talk component may be used.
[0122]
Further, by providing all of the sound processing devices shown in FIG. 2, FIG. 4, and FIG. 5 on the headrest portion 30 side, like the headrest portion 30 of the sound processing device of the first embodiment described above. By configuring the headrest part so that it can be removed from the backrest part, even when the headrest part is attached to the backrest part of another chair, the sound image is always localized at a predetermined position, Audio can be heard.
[0123]
Moreover, the adapter which consists of each part other than a right-and-left speaker can be comprised, and the sound processing apparatus by this invention can also be comprised by this adapter and the headrest part which provided the speaker. Also, the sound processing apparatus 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 playback device side of the audio signal.
[0124]
In the acoustic processing apparatuses of the first and second embodiments described above, the ultrasonic tweeter for detecting the position of the listener's head using the super tweeters of the speakers SL and SR mounted on the headrest unit 30 is used. The transmitter is used as a transmitter and also as a receiver for receiving a reflected wave that is transmitted back from the listener's head.
[0125]
Therefore, since it is not necessary to newly provide an ultrasonic transmitter and receiver, it is possible to realize an acoustic processing device equipped with a function for detecting the position of the listener's head at a relatively low cost.
[0126]
In the case of the first and second embodiments described above, the position of the listener's head with respect to the headrest portion 30 is measured constantly or at any time, and a transfer function corresponding to the measured position is obtained. By performing appropriate correction processing (trans-oral processing), avoiding the situation of lack of virtual speaker localization effect due to the incorrect measurement position of the listener's head and the listening position as in the past, the position of the listener's head Therefore, it is possible to realize the effects such as the front localization of the sound image as in the first embodiment and the all-round localization of the sound image as in the second embodiment.
[0127]
[Third Embodiment]
By the way, in order to realize a sound processing device capable of providing higher-quality sound, the detection accuracy of the position of the listener's head relative to the headrest portion is increased, and the correction processing by the transoral system for the sound signal is more strictly performed. There is a demand to be able to do it.
[0128]
Therefore, also in the sound processing apparatus of the third embodiment, the ultrasonic waves for detecting the position of the listener's head are used in the case of the sound processing apparatuses of the first and second embodiments described above. Similarly, transmission is performed from the super tweeters of the speakers SL and SR provided in the headrest unit 30.
[0129]
However, in the acoustic processing apparatus of the third embodiment, the reflected ultrasonic wave transmitted is received by the headrest unit 30 or a plurality of ultrasonic receiving elements provided in the vicinity thereof, and more The position of the listener's head can be detected with high accuracy.
[0130]
FIG. 8 is a block diagram for explaining the sound processing apparatus 4 of the third embodiment. As shown in FIG. 8, the sound processing device 4 of the third embodiment includes a headrest 90 provided with left and right two-channel speakers SL and SR, and a plurality of ultrasonic receiving elements, and a plurality of Except for the head position detection unit 40A that receives the detection output from the receiving element, the configuration is the same as that of the sound processing apparatus of the first embodiment shown in FIG.
For this reason, in the sound processing apparatus 4 of the third embodiment shown in FIG. 8, the parts configured similarly to the sound processing apparatus 1 of the first embodiment shown in FIG. The same reference numerals as those of the sound processing apparatus 1 of the form are attached, and the description thereof is omitted.
[0131]
As described above, in the case of the acoustic processing device 4 according to the third embodiment shown in FIG. 8, six ultrasonic receiving elements (ultrasonic sensing elements) SS <b> 1 to SS <b> 6 are provided on the headrest 90. It is 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 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.
[0132]
FIG. 9 is a diagram for explaining the process of detecting the position of the listener's head performed in the sound processing apparatus according to the third embodiment. As shown in FIG. 9, ultrasonic waves having different frequencies are transmitted from the left and right speakers SL, SR whose sound emitting surfaces are originally directed in the direction in which the listener's head is located, and the listener of the transmitted ultrasonic waves The reflected waves from the head of the receiver are received by the receiving elements SS1 to SS6.
[0133]
In the example shown in FIG. 9, an ultrasonic wave with a frequency of 40 kHz is transmitted from the super tweeter of the left speaker SL, and an ultrasonic wave with a frequency of 50 kHz is transmitted from the super tweeter of the right speaker SR. . By doing so, the accuracy of position detection is further improved.
[0134]
As shown in FIG. 9A, when none of the receiving elements SS1 to SS6 provided in the headrest unit 90 can receive the reflected wave of the ultrasonic wave transmitted from the left and right speakers SL and SR super tweeters. The position of the listener's head can be detected as being at a position away from the headrest 90 by a predetermined distance or more.
[0135]
Further, as shown in FIG. 9B, the reflected wave from the listener's head transmitted from the super tweeter of the left speaker SL, that is, a 40 kHz ultrasonic wave is received by the receiving element SS3, and the right speaker SR. When a reflected wave from the listener's head transmitted from the super tweeter, that is, an ultrasonic wave of 50 kHz is received by the receiving element SS1, the position of the listener's head is the position of the headrest 90. It can be detected that the position is on the left speaker SL side.
[0136]
Although not shown, contrary to the case of FIG. 9B, the reflected wave from the listener's head transmitted from the super tweeter of the left speaker SL, that is, a 40 kHz ultrasonic wave is received by the receiving element SS6. When the reception element SS4 receives the reflected wave from the listener's head transmitted from the super tweeter of the right speaker SR, that is, the ultrasonic wave of 50 kHz, the position of the listener's head is It can be detected that the headrest 90 is in the position on the right speaker SL side.
[0137]
Further, as shown in FIG. 9C, the reflected wave from the listener's head transmitted from the super tweeter of the left speaker SL, that is, a 40 kHz ultrasonic wave is received by the receiving element SS3, and the right speaker SR. When the reception element SS4 receives an ultrasonic wave reflected from the head of the listener transmitted from the super tweeter, that is, an ultrasonic wave of 50 kHz, the position of the head of the listener is the left and right of the headrest unit 90. It can be detected that the speaker is located at an intermediate position between the speakers SL and SR.
[0138]
As described above, depending on which receiving element of the six receiving elements provided in an array on the headrest 90 receives ultrasonic waves having different frequencies transmitted from the super tweeters of the left and right speakers SL and SR. Thus, an offset (shift) of the listener's head relative to the headrest portion 90 can be detected.
[0139]
Further, for the ultrasonic waves transmitted from the super tweeters of the left and right speakers, by measuring the time from the transmission to reception by the receiving element, the headrest portion is determined according to the time and the ultrasonic velocity. The distance from 90 to the listener's head can be detected. Based on the offset of the listener's head relative to the headrest 90 and the distance, the position of the listener's head relative to the headrest 90 can be detected more accurately.
[0140]
And 40 A of detection parts detect the exact position of a listener's head based on the detection output from each receiving element provided in the headrest part 90 at the array form. That is, as described above, the detection unit 40A determines which receiving element has received the ultrasonic wave transmitted from the super tweeter of each of the left and right speakers, and further, the ultrasonic wave transmitted from the super tweeter of each of the left and right speakers. The position of the listener's head is detected in consideration of the time from transmission to reception.
[0141]
Then, as in the case of the CPU 50 of the sound processing apparatus 1 of the first embodiment described above, the CPU 50 stores data corresponding to the current position of the listener's head relative to the headrest unit 90 from the detection unit 40A. The data read from 60 and the read data (coefficient data, function data, parameters, etc.) are supplied to the intended filters 21, 22, 23, 24 of the transoral system filter unit 20.
[0142]
Thereby, in the trans-oral system unit 20, a correction process is performed 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 is Even if the position of the listener's head changes with respect to the headrest unit 90, the sound image of the sound emitted from the left and right speakers can be localized at the virtual speaker position.
[0143]
In the case of the acoustic processing apparatuses 1, 2, 3, and 4 of the first to third embodiments described above, ultrasonic waves are used to detect the position of the listener's head. Since the ultrasonic waves cannot be heard as sounds by human ears, the listener does not notice that the head is being detected.
[0144]
In addition, in the case of a normal music component, an ultrasonic component that is related to detection accuracy (measurement accuracy) is not included, so that there is no problem of interference with reproduced sound (music signal) for listening purposes. That is, during music playback, the position of the listener relative to the speaker can be measured and detected without deteriorating the reproduced sound and without being noticed by the listener.
[0145]
In the acoustic processing apparatus 4 of the third embodiment described above, six ultrasonic receiving elements are provided in the headrest portion 90, but the present invention is not limited to this, and more ultrasonic receiving elements are provided. Of course, a plurality of receiving elements may be provided in a plurality of rows. Further, the interval between the receiving elements and the direction of the sound emitting surface of the left and right speakers SL and SR can be appropriately adjusted.
[0146]
Further, the position where the ultrasonic receiving element is provided may be provided in an arbitrary place where reflection from the head of the listener can be received, in addition to the headrest 90 and its vicinity.
[0147]
Further, instead of the trans-oral system filter unit 20, a simplified trans-oral system unit 70 used in the modification of the first embodiment shown in FIG. 5 may be used. Further, instead of the 2-channel sound image localization processing filter unit 10, a multi-channel, for example, 5-channel sound image localization processing filter 80 may be used.
[0148]
Therefore, also in the case of the sound processing device of the third embodiment described above, as in the case of the sound processing device of the first and second embodiments described above, the head of the listener with respect to the headrest portion 90 is The measurement position and listening position of the listener's head as in the past by measuring the position always or as needed and performing correction processing (transoral processing) according to the transfer function according to the measured position. Thus, it is possible to avoid the lack of the virtual speaker localization effect due to the inaccuracy of the sound and to achieve the effects such as the front localization of the sound image and the all-round localization of the sound image without being influenced by the position of the listener's head.
[0149]
[Fourth Embodiment]
In the first to third embodiments described above, the position of the listener's head relative to the headrest portion provided with the speaker is detected by transmitting ultrasonic waves and receiving the reflected waves. However, detection of the position of the listener's head is not limited to using ultrasonic waves.
[0150]
For example, videophones capable of transmitting and receiving not only voice but also images have been used at home. Therefore, for example, as shown in FIG. 10, a so-called home theater system is formed by a TV set (TV set) 200 and a chair on which a sound processing device having a headrest portion 30 provided with left and right two-channel speakers SR and SL is mounted. In such a case, the CCD camera 210 that is usually used for a videophone can be used for detecting the position of the listener's head relative to the headrest 30.
[0151]
Also, it is often the case that sound such as music is listened to in a car (vehicle interior). Therefore, as shown in FIG. 11, it is conceivable to configure the sound processing apparatus by providing a headrest portion on which two left and right channel speakers (SL1, SR1 or SL2, SR2) are mounted on a seat in the automobile. In such a case, by mounting, for example, a videophone CCD camera 310 in the car, the videophone CCD camera 310 can be used to detect the position of the listener's head relative to the headrest portion. .
[0152]
Even in the present situation, in some types of automobiles, in order to eliminate blind spots, a CCD camera is provided outside the automobile, and an image captured through the CCD camera is displayed on a display inside the automobile for viewing. What can be done is also provided, and it is possible to mount a CCD camera for in-car imaging on a car.
[0153]
Therefore, the acoustic processing apparatus according to the fourth embodiment uses a CCD camera (CCD apparatus) provided in the home or in the car to determine the position of the listener's head relative to the headrest portion provided with the speaker. You can enjoy the virtual speaker localization effect in a more free posture by grasping in real time how much your head is sitting with respect to the speaker and using a transfer function suitable for that position in the system It is something that can be done.
[0154]
Note that the sound processing device 5 of the fourth embodiment can also process left and right two-channel audio signals, as in the case of the sound processing device 1 of the first embodiment described above. In addition, 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 forward 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 is emitted from the virtual speakers VSL and VSR.
[0155]
FIG. 12 is a block diagram for explaining the sound processing apparatus 5 according to the fourth embodiment. As described with reference to FIGS. 10 and 11, the sound processing apparatus 5 shown in FIG. 12 is provided in a home room or an automobile. The sound processing device 5 shown in FIG. 12 analyzes the CCD camera 210 and the image captured by the CCD camera 210, and detects the position of the listener's head relative to the headrest 30. Except for the section 40D, the configuration is the same as that of the sound processing apparatus 1 of the first embodiment shown in FIG.
[0156]
For this reason, in the sound processing apparatus 5 of the fourth embodiment shown in FIG. 12, the same reference numerals are used for the parts configured similarly to the sound processing apparatus 1 of the first embodiment shown in FIG. The description of the portion is omitted.
[0157]
In the acoustic processing apparatus 5 of the fourth embodiment, the CCD camera 210 is set so as to be directed toward the listener, and can always take an image in the listener direction. Then, for example, the CCD camera 210 captures an image in the direction of the listener while the sound processing device 5 is operating under control of the CPU 50 or at predetermined timings, and performs image analysis on the captured image. To the unit 40D.
[0158]
The image analysis unit 40D performs an analysis process of the image data from the CCD camera 210, detects the position of the listener's head with respect to the headrest unit 30, and notifies the CPU 50 of this. Specifically, the position of the speaker of the headrest 30 can be confirmed by image processing by marking a predetermined position such as a chair on which a listener sits or a headrest portion of the seat.
[0159]
Since the listener always moves a little while sitting on the chair, the edge portion of the listener can be extracted by using this and taking the time axis difference of the still image. The positional relationship between the listener's head and the speakers SL and SR of the headrest 30 can be understood from the edge portion of the listener and the position of the speaker.
[0160]
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 unit 40D, and supplies this to the corresponding filter of the transoral system filter unit 20. To do.
[0161]
Thereby, in the trans-oral system filter unit 20, the sound signal subjected to the sound image localization process is corrected according to the position of the listener's head, and the position of the listener's head with respect to the headrest unit 30 is determined. Even in the case of a change, the sound image of the sound emitted from the left and right speakers SL, SR of the headrest unit 30 can be localized so that the sound is emitted from the virtual speakers VSL, VSR.
[0162]
Note that when analyzing an image captured by the CCD camera 210, a case where the head moves in the vertical direction, which is a direction orthogonal to the head contact surface of the headrest unit 30, and a case where the head contact of the headrest unit 30 occurs. When the head moves in the horizontal direction, which is a direction parallel to the surface, the latter horizontal movement can be detected more easily.
[0163]
Originally, since the speaker is provided in the headrest portion 30 and is located in the vicinity of the listener's ear, even if the listener's head moves by the same amount, the speaker is orthogonal to the head contact surface of the headrest portion 30. Direction when the head moves in the vertical direction, which is the direction of the head, and when the head moves in the horizontal direction, which is the direction parallel to the head contact surface of the headrest portion 30, Change of transfer function from speaker to listener's ear is important.
[0164]
For this reason, in the sound processing apparatus 5 of the fourth embodiment, the horizontal position (offset) of the listener's head is sensed by analyzing the image captured by the CDD camera 210, and Accordingly, by using an appropriate filter coefficient for each filter of the transoral system fill unit 20, the sound image of the sound emitted from the left and right speakers SL, SR of the headrest 30 can be accurately set at a predetermined position. To be localized.
[0165]
In the acoustic processing apparatus 5 of the fourth embodiment, the simplified transoral is used in the modification of the first embodiment shown in FIG. 5 instead of the transoral system filter unit 20. The system unit 70 can also be used. Further, instead of the 2-channel sound image localization processing filter unit 10, a multi-channel, for example, 5-channel sound image localization processing filter 80 may be used.
[0166]
Therefore, in the case of the sound processing apparatus according to the fourth embodiment, as in the case of the sound processing apparatuses according to the first, second, and third embodiments described above, the listener's head with respect to the headrest portion 30 is used. By measuring the position of the part constantly or at any time and performing correction processing (trans-oral processing) according to the transfer function according to the measured position, Avoiding the lack of virtual speaker localization due to incorrect listening position, and achieving effects such as sound image localization and sound image all-around localization without being affected by the position of the listener's head .
[0167]
In the first, second, and fourth embodiments described above, the sound emitting surface of the speaker provided in the headrest portion is parallel to the surface that the head of the headrest portion contacts. Although shown, it is also possible to make appropriate corrections such as tilting the sound emitting surface of the speaker provided in the headrest portion toward the listener.
[0168]
In the above-described embodiment, an example in which the left speaker SL and the right speaker SR are provided in the headrest portion has been described. However, the number of speakers is not necessarily two, and 1 There may be one or more than two. It goes without saying that a so-called HiFi-oriented speaker device equipped with a twitter or the like can be used.
[0169]
Further, the sound processing device shown in FIGS. 1, 5, 6, 8, and 12 is all provided on the headrest side so that the headrest portion can be removed from the backrest portion. The headrest part can be used by being mounted on the backrest part of another chair.
[0170]
Moreover, in the sound processing apparatus shown in FIG. 1, FIG. 5, FIG. 6, FIG. 8, and FIG. 12, an adapter composed of each part other than the left and right speakers is configured, The sound processing apparatus according to the present invention can also be configured. Also, the sound processing apparatus 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 playback device side of the audio signal.
[0171]
【The invention's effect】
As described above, the position of the listener's head relative to the speaker can be detected, and the sound signal subjected to the sound image localization processing can be corrected according to the actual position of the listener's head. As a result, the degree of freedom of the position of the listener's head relative to the speaker is increased, and a highly reliable acoustic processing device is provided that does not reduce the effect of sound image localization due to slight movement of the listener's head. be able to.
[Brief description of the drawings]
FIG. 1 is a block diagram for explaining a first embodiment of a sound processing apparatus according to the present invention;
FIG. 2 is a diagram for explaining an appearance of a chair on which the sound processing apparatus according to the first embodiment is mounted.
FIG. 3 is a diagram for explaining the principle of sound image localization processing performed in the sound processing apparatus according to the first embodiment shown in FIG. 1;
4 is a diagram for explaining processing for detecting the position of a listener's head performed in the sound processing apparatus according to the first embodiment shown in FIG. 1; FIG.
FIG. 5 is a block diagram for explaining a modification of the sound processing apparatus according to the first embodiment shown in FIG. 1;
FIG. 6 is a block diagram for explaining a second embodiment of the sound processing apparatus according to the present invention;
7 is a diagram for explaining the principle of sound image localization processing performed in the sound processing apparatus according to the second embodiment shown in FIG. 6; FIG.
FIG. 8 is a block diagram for explaining a third embodiment of the sound processing apparatus according to the present invention;
FIG. 9 is a diagram for explaining the process of detecting the position of the listener's head performed in the sound processing apparatus according to the third embodiment shown in FIG. 8;
FIG. 10 is a diagram for explaining an example of a usage mode of the sound processing apparatus according to the fourth embodiment of the invention;
FIG. 11 is a diagram for explaining another example of a usage mode of the sound processing apparatus according to the fourth embodiment of the invention;
FIG. 12 is a block diagram for explaining a sound processing apparatus according to a fourth embodiment of the present invention;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Sound image localization process filter part, 11-14 ... Filter, 15, 16 ... Adder part, 20 ... Trans-oral system filter part, 21-24 ... Filter, 25, 26 ... Adder part, 30 ... Headrest part, SL ... Left Speaker, SR ... Right speaker, VSL ... Virtual left speaker, VSR ... Virtual right speaker, 40 ... Head position detection unit, 50 ... CPU, 60 ... Database, 70 ... Simplified transoral system filter unit, 41, 42 ... Filter , 80 ... Sound image localization processing filter unit, 81-90 ... Filter, 91, 92 ... Adder, SS1-SS6 ... Ultrasonic wave receiving element, 210, 310 ... CCD camera

Claims (2)

A speaker device;
A sound image localization processing unit that performs processing to localize a sound image of the sound by the sound signal to a predetermined position with respect to the sound signal to be supplied to the speaker device;
A correction processing unit configured to perform a correction process according to the position of the listener's head relative to the speaker device with respect to the audio signal from the sound image localization processing unit;
Ultrasonic transmitting means for transmitting ultrasonic waves, ultrasonic receiving means for receiving reflected ultrasonic waves transmitted from the ultrasonic transmitting means and reflected by the listener's head, and reflected ultrasonic waves by the ultrasonic receiving means Of the listener, and when the reflected ultrasonic wave is received by the ultrasonic wave receiving means, based on the speed of the ultrasonic wave and the time from transmission of the ultrasonic wave until reception of the reflected ultrasonic wave, A head position detection unit comprising head position specifying means for specifying the position of the head relative to the speaker ;
A control unit configured to control the correction processing unit according to a detection result from the head position detection unit ,
The ultrasonic transmission unit and the ultrasonic reception unit are acoustic processing apparatuses that are high-frequency speakers of the speaker device. A speaker device;
A sound image localization processing unit that performs processing to localize a sound image of the sound by the sound signal to a predetermined position with respect to the sound signal to be supplied to the speaker device;
A correction processing unit configured to perform a correction process according to the position of the listener's head relative to the speaker device with respect to the audio signal from the sound image localization processing unit;
Ultrasonic transmitting means for transmitting ultrasonic waves, ultrasonic receiving means for receiving reflected ultrasonic waves transmitted from the ultrasonic transmitting means and reflected by the listener's head, and reflected ultrasonic waves by the ultrasonic receiving means Of the listener, and when the reflected ultrasonic wave is received by the ultrasonic wave receiving means, based on the speed of the ultrasonic wave and the time from transmission of the ultrasonic wave until reception of the reflected ultrasonic wave, A head position detection unit comprising head position specifying means for specifying the position of the head relative to the speaker;
A control unit configured to control the correction processing unit according to a detection result from the head position detection unit;
With
The ultrasonic transmission means is a high-frequency speaker of the speaker device with two channels on the left and right,
The ultrasonic receiving means comprises a plurality of ultrasonic sensing elements arranged in a predetermined position,
An acoustic processing apparatus that transmits ultrasonic waves of different frequencies from the high-frequency speakers of the two left and right channels .

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