JP4158019B2 - Distance measurement correction system, distance measurement device, and distance measurement correction device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a signal from a measurement microphone without using a reference signal in a multi-channel sound reproduction environment in which a multi-channel sound signal reproduced by a DVD (Digital Versatile Disc) device or the like can be heard, for example. The distance measurement correction system, the distance measurement correction device, and the distance that measure the relative value of the distance from each speaker to the listening position (listening position) and automatically adjust the delay time of the audio signal of each channel. It relates to a measuring device.
[0002]
[Prior art]
At present, in a multi-channel sound output device using a DVD or the like as a source, generally, in order to measure the sound characteristics of each sound channel, pink sound or white called test tone is individually used for each sound channel. The noise is reproduced, confirmed by the user's ear, and the level difference of each channel is manually adjusted by the user using a remote controller or the like.
[0003]
Also, in a high-grade AV (Audio and Visual) amplifier device, a measurement microphone is placed at the listening position, a test tone generator is prepared inside the AV amplifier device, and a test tone is reproduced for each audio channel. The sound is picked up by a measurement microphone, the signal is taken in, and the original test tone is used as a reference signal, which is analyzed by a fast Fourier transform (hereinafter abbreviated as FFT in this specification) and automatically. Some have the ability to adjust the distance difference.
[0004]
In addition, as a technique related to the technique for making the latter AV amplifier device or the like have an acoustic characteristic measurement correction function, the acoustic characteristic measuring apparatus described in Patent Document 1 or the transfer function described in Patent Document 2 are used. There are a measuring apparatus, a delay time measuring method and apparatus described in Patent Document 3, and the like.
[0005]
[Patent Document 1]
JP-A-8-184488
[0006]
[Patent Document 2]
JP-A-8-184624
[0007]
[Patent Document 3]
JP-A-8-194027
[0008]
[Problems to be solved by the invention]
However, in the case of the above-mentioned method, in which the user confirms and adjusts with his / her ears, it takes time and effort, and it is difficult to make an accurate adjustment. For users who are unfamiliar with the operation of the apparatus, this is a troublesome task.
[0009]
In the latter method, which is a method for providing a multi-channel sound output device such as an AV amplifier device having an acoustic characteristic measurement correction function, a reference signal must be used for measurement analysis. In that case, when the measurement device is separated from the multi-channel sound output device such as an AV amplifier device, it is necessary to capture a reference signal from the multi-channel sound output device in addition to the signal from the measurement microphone.
[0010]
For this reason, a configuration in which the measuring device generates a test tone and supplies it to a multi-channel sound output device such as an AV amplifier device is conceivable. In this case, however, the delay time of the test tone in the supply path is accurately grasped. Otherwise, the subsequent analysis may not be performed accurately.
[0011]
In addition, it is conceivable to install the function of a measuring device in a multi-channel sound output device such as an AV amplifier device, but if the distance between each speaker and the listener can be accurately grasped without using a reference signal in the first place. The sound system can be flexibly constructed.
[0012]
In view of the above, the present invention is a distance measurement correction system capable of accurately grasping the positional relationship between a speaker and a listening position and automatically adjusting the delay time of each audio channel without using a reference signal. Another object of the present invention is to provide a distance measurement device and a distance measurement correction device.
[0013]
[Means for Solving the Problems]
In order to solve the above-described problem, the distance measurement correction system according to the invention described in claim 1 provides:
Distance measurement of a speaker connected to each of the plurality of sound channels of the sound output device by receiving the collected sound from a sound output device having a plurality of sound channels and a microphone arranged at a listening position A distance measurement correction system comprising a measurement device for performing
The acoustic output device is
Select the reference audio channel and other audio channels, and through the selected audio channel A pulse signal of a predetermined shape, wherein the polarity is different between the reference audio channel and the other audio channel Switching means for outputting a test signal and switching the other audio channel to another audio channel every predetermined period;
Delay means for receiving a distance parameter from the measuring device and controlling a delay time of an audio signal for each of the plurality of audio channels;
With
The measuring device is
The relative distance of the measurement target speaker with respect to the listening position is determined based on a measurement signal including the sound from the speaker of the reference sound channel and the sound from the speaker of the other sound channel collected by the microphone. A distance measuring means,
Based on the measurement result of the distance measuring means, a distance parameter for the other audio channel is formed, Above Parameter forming means for supplying to the sound output device;
It is characterized by providing.
[0014]
According to the distance measurement correction system of the first aspect of the present invention, the sound output device includes a plurality of audio channels, and the switching means passes through a predetermined reference audio channel and other audio channels, A pulse signal having a predetermined shape and having a different polarity between the reference audio channel and the other audio channel A test signal is output, and other audio channels other than the reference audio channel are sequentially switched to other audio channels every predetermined period.
[0015]
The output sound from the selected audio channel is collected by a measurement microphone arranged at the listening position, and this collected signal is supplied as a measurement signal to the distance measuring means of the measurement device, where the measurement target speaker and The relative value of the distance to the listening position is obtained.
[0016]
Such processing is performed by sequentially changing other audio channels without changing the reference audio channel, and the relative distance between the speakers of the reference audio channel and the speakers of all other audio channels with respect to the listening position. A value is determined.
[0017]
Based on this relative value, the parameter forming means forms a distance parameter to be set in the delay means of the sound output device, which is provided to the sound output device to adjust (correct) the delay time of the delay means.
[0018]
Accordingly, the reference signal itself is not used for distance measurement, and the speaker is not troubled by the user who is a listener based only on the sound corresponding to the test signal (test tone) emitted from the speaker. And the relative distance between the listening position and the listening position can be accurately grasped, and the delay time of each audio channel can be automatically adjusted to an appropriate one.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a distance measurement correction device, a distance measurement correction system, and a distance measurement device according to the present invention will be described with reference to the drawings.
[0020]
[First Embodiment]
[Configuration of distance measurement correction system]
FIG. 1 is a block diagram for explaining a distance measurement correction system according to the first embodiment formed by applying a distance measurement correction system according to the present invention. As shown in FIG. 1, the distance measurement correction system of this embodiment includes a multi-channel sound output device 1 having a plurality of audio channels and a measurement device 2.
[0021]
A multi-channel sound output device (hereinafter simply referred to as a sound output device) 1 is a device such as an AV amplifier device, for example, and in this embodiment can cope with 5.1 channel audio signals. The measuring device 2 is configured by applying the distance measuring device according to the present invention, and is a device such as a personal computer provided with a microphone terminal that receives supply of a collected sound signal from a microphone.
[0022]
As shown in FIG. 1, the sound output device 1 includes a multi-channel audio signal input terminal 11, a decoder 12, a switch unit 13, a delay unit 14, an amplification unit 15, and a test signal generator 16. It is provided. As shown in FIG. 1, each of the switch unit 13, the delay unit 14, and the amplification unit 15 includes switch circuits 131 to 136, delay circuits 141 to 146, and amplification circuits 151 to 156 provided corresponding to each audio channel. It is equipped with.
[0023]
For example, an audio signal encoded in a multi-channel format from a DVD or the like is supplied to the decoder 12 through the input terminal 11. The decoder 12 decodes the multi-channel audio signal supplied thereto, divides it into audio signals for each audio channel, and outputs them to the corresponding audio channel.
[0024]
The audio signal output from the decoder 12 to each audio channel is supplied to the delay circuits 141 to 146 through the switch circuits 131 to 136. As will be described later, each of the switch circuits 131 to 136 is a speaker to be processed (two selected in this embodiment) when measuring the positional relationship between the speaker and the listening position (listening position). This is an on / off switch for supplying a test signal (test tone) only to the speaker.
[0025]
The delay circuits 141 to 146 perform a delay process on each audio signal of each audio channel so as to adjust a sense of distance between the speaker and the listening position.
[0026]
In this embodiment, the switch circuits 131 to 136 of the sound output device 1 are switched based on a control signal from the measurement device 2 described later, and the delay circuits 141 to 146 are the measurement device 2. Is supplied with the distance parameter, and the delay time of the audio signal of the corresponding audio channel is adjusted accordingly.
[0027]
The audio signals output from each of the delay circuits 141 to 146 are supplied to the corresponding amplifier circuits 151 to 156, where the levels are adjusted and supplied to the speakers corresponding to the respective audio channels. In the present embodiment, as shown in FIG. 1, corresponding speakers SP <b> 1 to SP <b> 6 are connected to each audio channel of the sound output device 1.
[0028]
Here, the speakers SP1, SP2, SP3, and SP4 are speakers installed in front of the listener, and are sequentially a front left speaker (L), a subwoofer (Sub), a center speaker (C), and a front light speaker. (R), and the speakers SP5 and SP6 are speakers installed behind the listener, and are, in order, a rear left speaker (SL) and a rear right speaker (SR). The rear left speaker (SL) is also called a surround left speaker, and the rear right speaker (SR) is also called a surround right speaker.
[0029]
Further, the acoustic output device 1 is provided with a test signal generator 16 as shown in FIG. The test signal generator 16 generates a predetermined test signal (test tone) at the time of a test and supplies it to each audio channel. The test signal generator 16 generates a pulse signal having a predetermined shape as a test signal. In this embodiment, the test signal generator 16 generates an impulse signal.
[0030]
At the time of the test, as described above, the switch circuits 131 to 136 are switched so as to output the test signal only through the two selected audio channels in accordance with a control signal from the measuring apparatus 2 described later.
[0031]
In this embodiment, as will be described in detail later, an audio channel connected to the speaker SP3 (center speaker (C)) is used as a reference channel (reference audio channel), and an audio channel connected to the speaker SP3 The test signal is output through two audio channels with another audio channel.
[0032]
In this embodiment, the other audio channel paired with the reference channel is sequentially changed without changing the audio channel connected to the speaker SP3 as the reference channel, and the test signal is changed. The sound corresponding to is always emitted from two audio channels of the reference channel and another audio channel.
[0033]
At the time of the test, as shown in FIG. 1, the measurement microphone Mic is installed at a listening position that is a position where the sound emitted from each of the speakers SP1 to SP6 is heard. The measurement microphone Mic is connected to the microphone connection terminal 21 of the measurement apparatus 2.
[0034]
A microphone amplifier 22, an A / D converter 23, and a peak detection calculation unit 24 are provided after the microphone terminal 21. The microphone amplifier 22 amplifies the analog sound pickup signal from the microphone Mic to a predetermined level and supplies it to the A / D converter 23. The A / D converter 23 converts the analog sound pickup signal supplied thereto into a digital signal and supplies it to the peak detection calculation unit 24.
[0035]
The peak detection calculation unit 24 detects the peak of the digital sound pickup signal supplied to the peak detection calculation unit 24, so that the speaker SP3 connected to the reference channel and the speakers other than the speaker SP3 connected to the other one audio channel are detected. A relative distance with respect to the listening position is obtained, and based on this, a distance parameter for the delay circuit of the audio channel to be measured is formed, and this is supplied to the audio output device 1 to the corresponding delay circuit of the delay unit 14. Try to set.
[0036]
Note that the peak detection calculation unit 24 of the measurement device 2 changes the delay time of the audio signals of the two audio channels to be measured during the test, so that the speaker connected to the two audio channels of the measurement object can change. In order to detect the positional relationship accurately and to select two audio channels to be tested, a switching control signal is supplied to the switch unit 13 of the audio output device 1 to select the audio channel to be measured. To be able to.
[0037]
That is, in this embodiment, as shown in FIG. 1, the measuring device 2 and the sound output device 1 are connected using a serial interface such as RS232C (Recommended Standard 232C) or USB (Universal Serial Bus). Thus, the sound output device 1 can be controlled from the measurement device 2.
[0038]
[Distance measurement correction processing]
Next, distance measurement correction processing performed in the distance measurement correction system of the first embodiment shown in FIG. 1 will be described with reference to the flowchart of FIG. FIG. 2 is a flowchart for explaining the flow of the distance measurement correction process performed in the distance measurement correction system of the first embodiment.
[0039]
As described above, in the distance measurement correction system according to the first embodiment, the audio channel (center channel Cch) connected to the center speaker SP3 is set as the reference channel (reference audio channel).
[0040]
Here, for each audio channel other than the center channel, the audio channel connected to the speaker SP1 is a front left channel (Lch), the audio channel connected to the speaker SP2 is a subwoofer channel (Subch), and is connected to the speaker SP4. The audio channel to be played is a front light channel (Rch). The audio channel connected to the speaker SP5 is referred to as a rear left channel (SLch), and the audio channel connected to the speaker SP6 is referred to as a rear right channel (SRch).
[0041]
First, the measuring device 2 controls the switch 13 of the sound output device 2, turns on the switch circuits 132 and 133, and turns off the others, and outputs test signals from the front left channel (Lch) and the center channel (Cch). Then, a process is performed to collect the test sound emitted from the speakers SP1 and SP3 and measure the time difference between the propagation times of the test signals from the speakers SP1 and SP3 (step S101).
[0042]
Next, the measuring device 2 controls the switch 13 of the sound output device 2, turns on the switch circuits 134 and 133, turns off the others, and outputs test signals from the front light channel (Rch) and the center channel (Cch). A process of collecting the test sound emitted from the speakers SP4 and SP3 and measuring the time difference in the propagation time of the test signal from the speakers SP4 and SP3 (processing for measuring the relative distance) is performed. (Step S102).
[0043]
Next, the measuring device 2 controls the switch 13 of the sound output device 2, turns on the switch circuits 135 and 133, and turns off the others, and outputs test signals from the surround left channel (SLch) and the center channel (Cch). A process for collecting the test sound emitted from the speakers SP5 and SP3 and measuring the time difference in the propagation time of the test signal from the speakers SP5 and SP3 (processing for measuring the relative distance) is performed. (Step S103).
[0044]
Next, the measuring device 2 controls the switch 13 of the sound output device 2, turns on the switch circuits 136 and 133, and turns off the others, and outputs test signals from the surround light channel (SRch) and the center channel (Cch). A process of collecting the test sound emitted from the speakers SP6 and SP3 and measuring the time difference in the propagation time of the test signal from the speakers SP6 and SP3 (processing for measuring the relative distance) is performed. (Step S104).
[0045]
Next, the measuring device 2 controls the switch 13 of the sound output device 2, turns on the switch circuits 131 and 133, turns off the others, and outputs test signals from the subwoofer channel (Subch) and the center channel (Cch). A process of measuring the time difference in the propagation time of the test signals from the speakers SP2 and SP3 by collecting the test sound emitted from the speakers SP2 and SP3 and performing the process (process for measuring the relative distance) is performed. (Step S105).
[0046]
Thereafter, the measurement apparatus 2 obtains the propagation time of the audio signal between the center channel Cch, which is the reference channel, and the other channels Lch, Rch, SLch, SRch, Subch, obtained by the processing in steps S101 to S105. The time difference (relative value) is converted into a distance (step S106). In a multi-channel sound output device, since the distance between the speaker and the listening position is often set, the propagation time is converted to a distance using the speed of sound.
[0047]
Then, the measuring apparatus 2 determines how much the audio signal of each audio channel is based on the distance corresponding to the time difference in propagation time between the center channel Cch obtained in step S106 and the other channels Lch, Rch, SLch, SRch, and Subch. A distance parameter indicating whether to delay is formed, and this is supplied to the delay unit 14 of the sound output device 1 and set in the delay circuits 141 to 146 of each channel, and the distance feeling between each speaker SP1 to SP6 and the listening position By adjusting (step S107), an optimum listening environment is prepared.
[0048]
For example, if the distance between the speaker of the center channel Cch and the listening position is 5 m (meters), the distance between the speakers of the other audio channels and the listening position is calculated by multiplying the time difference by the speed of sound to 5 m. The distance obtained by adding is provided to the delay unit 14 of the sound output device 1 as a distance parameter (parameter value).
[0049]
[Details of channel time difference measurement]
And in each process of step S101-step S105 shown in FIG. 2, in order to grasp | ascertain correctly the positional relationship of the speaker of two audio channels to be processed, in the distance measurement correction system of this embodiment, By repeating the measurement while changing the delay amount for each of the two audio channels to be processed, it is possible to accurately determine which audio channel the speaker connected to is close to the listening position. .
[0050]
The flowcharts of FIGS. 3 to 5 and the diagrams of FIGS. 6 to 7 are for explaining details of processing performed in each of steps S101 to S105 shown in FIG. The processes performed in steps S101 to S105 in FIG. 2 will be described in detail with reference to these drawings.
[0051]
In FIG. 2, the procedure has been described in which distance parameters for each audio channel other than the reference channel are collectively formed and provided to the sound output device 2 for setting. However, since it is also possible to form a distance parameter for each audio channel other than the reference channel to be measured and provide it to the acoustic output device 1, in FIG. An example will be described in which a distance parameter is formed and set for each audio channel.
[0052]
First, the measuring device 2 controls the delay unit 14 of the sound output device 1 to control the delay circuits of the two audio channels to be processed, so that the delay amounts of the two audio channels to be processed are the same. (Step S201). Here, the speaker of the reference channel is indicated by the speaker SPr, and the speaker of the other audio channel is indicated by the speaker SPn.
[0053]
Then, the sound output device 2 generates a test signal (impulse signal) by the test signal generator 16 and supplies it to the two speakers SPn and SPr to be measured, and the test sound from the two speakers SPn and SPr. Is emitted (step S202). Then, the measuring device 2 takes in the analog sound pickup signal (measurement signal) from the measurement microphone Mic that picks up the test sound from the two speakers SPn and SPr as a digital signal (step S203), and this taken signal To detect a peak (step S204).
[0054]
The peak detection process in step S204 will be described in detail. The acquired sound pickup signal is converted into dB (gain conversion), and the value is the largest with respect to other values, and the total average of other values is compared with that. Data having a difference of a certain value or more (for example, 40 dB or more) is regarded as a peak. A point in time at which this peak exists is defined as a propagation point (propagation time) up to the listening position.
[0055]
When two peaks are present, the positions of the speaker SPr and the speaker SPn are deviated, so the distance between the two peaks is determined based on the sound propagation time from the speaker SPr to the listening point and the speaker SPn. A time difference d from the sound propagation time to the point is set (step S205).
[0056]
Then, it is determined whether or not the time difference d is 0 (step S206). If it is determined that the time difference d is 0, there is no distance difference between the speaker SPn and the speaker SPr, so The delay time is set to 0 (zero), and the delay time for the audio channel of the speaker SPn is set to 0 (zero), which is set in the corresponding delay circuit of the delay unit 14 of the sound output device 2 (step S207). -The process of FIG. 5 is complete | finished.
[0057]
If it is determined in step S206 that the time difference d is not 0 (zero), the process proceeds to the process shown in FIG. 4, and the measurement device 2 controls the delay unit 14 of the sound output device 1 to perform reference. The audio signal of the other audio channel (audio channel of the speaker SPn) other than the channel is delayed by a predetermined time t (step S208).
[0058]
Then, similarly to the processing from step S202 to step S205 shown in FIG. 3, the sound output device 2 causes the test signal generator 16 to generate a test signal (impulse signal), which is designated by two speakers. The signals are supplied to SPn and SPr, and the test sound is emitted from the two speakers SPn and SPr (step S209).
[0059]
Then, the measuring apparatus 2 takes in the analog sound pickup signal from the measurement microphone Mic that picks up the test sound from the two speakers SPn and SPr as a digital signal (step S210), and detects the peak from the acquired signal. (Step S211).
[0060]
As in step S205, the distance between the two peaks is the time difference d1 between the sound propagation time from the speaker SPr to the listening position and the sound propagation time from the speaker SPn to the listening position (step S212). ). After the delay time for the audio signal of the audio channel of the speaker SPn is cleared, the original state is restored (step S213).
[0061]
In this way, by shifting the audio signal of the audio channel of the speaker SPn by the time t and performing the measurement again, in step S212, it is known whether the distance between the speaker SPn and the speaker SPr is increased or decreased. To be able to.
[0062]
Next, in the distance measurement correction system of this embodiment, the process proceeds to the process shown in FIG. 5, and the measurement device 2 controls the delay unit 14 of the sound output device 1 to control the reference channel (the sound of the speaker SPr). (Channel) audio signal is delayed by a predetermined time t (step S214).
[0063]
Then, similarly to the processing from step S202 to step S205 shown in FIG. 3 and the processing from step S209 to step S212 shown in FIG. 4, the sound output device 2 uses the test signal generator 16 to generate a test signal (impulse). Signal) is supplied to the two specified speakers SPn and SPr, and the test sound is emitted from the two speakers SPn and SPr (step S215).
[0064]
Then, the measuring apparatus 2 takes in the analog sound pickup signal from the measurement microphone Mic that picks up the test sound from the two speakers SPn and SPr as a digital signal (step S216), and detects the peak from the acquired signal. (Step S217). Similarly to the case of step S212, the distance between the two peaks is defined as a time difference d2 between the sound propagation time from the speaker SPr to the listening position and the propagation time from the speaker SPn to the listening position (step S218).
[0065]
As described above, by shifting the audio signal of the audio channel of the speaker SPr by the time t and performing the measurement again, in step S218, it is known whether the distance between the speaker SPn and the speaker SPr is increased or decreased. To be able to.
[0066]
Then, in the measuring apparatus 2, it is determined whether or not the time difference d1 obtained in step S212 shown in FIG. 4 is larger than the time difference d2 obtained in step S218 (step S219).
[0067]
If it is determined in step S219 that the time difference d1 is greater than the time difference d2, the speaker SPn is located farther from the listening position where the measurement microphone Mic is installed than the speaker SPr of the reference channel. Is determined (step S220).
[0068]
In this case, the delay amount with respect to the audio signal of the audio channel (reference channel) of the speaker SPr is set to 0 (zero), and the delay amount with respect to the audio signal of the audio channel of the speaker SPn is set as the time difference d, based on this time difference d. A distance parameter for the audio signal of the audio channel of the speaker SPn is formed and supplied to the delay unit 14 of the sound output device 1 and set in the corresponding delay circuit (step S221), as shown in FIGS. Terminate the process.
[0069]
If it is determined in step S219 that the time difference d1 is not larger than the time difference d2, the position of the reference channel speaker SPr is farther from the listening position where the measurement microphone Mic is installed than the speaker SPn. (Step S222). In this case, the calculation represented by the time difference d = d * (− 1) is performed (step S223). In the above formula, the symbol * (asterisk) is used as a multiplication symbol. This is the same in step S223 in FIG.
[0070]
Then, the delay amount with respect to the sound signal of the sound channel (reference channel) of the speaker SPr is set to 0 (zero), and the delay amount with respect to the sound signal of the sound channel of the speaker SPn is set to the time difference −d (minus d). Based on this, a distance parameter for the audio signal of the audio channel of the speaker SPn is formed and supplied to the delay unit 14 of the sound output device 1 and set in the corresponding delay circuit (step S221). The indicated process ends.
[0071]
As described above, the position of the speaker SPn of the other one audio channel with respect to the listening position of the speaker SPn is grasped on the basis of the position of the speaker SPr of the reference channel, and the delay time (delay amount) of the audio signal of the audio channel of the speaker SPn By controlling, the position where the sound emitted from the speaker SPn can be heard is adjusted.
[0072]
The processing shown in FIGS. 3 to 5 is performed by changing one audio channel other than the reference channel in each step in each step of steps S101 to S105 of the processing shown in FIG. Adjust the position of the speaker for one audio channel.
[0073]
That is, in step S221, the position where the listener feels that the speaker SPn is emitting sound with reference to the position of the speaker SPr of the reference channel, instead of physically moving the position of the speaker SPn (virtual). Is corrected by correcting the delay amount with respect to the audio signal of the audio channel of the speaker SPn.
[0074]
Here, the measurement of the distance from the speaker SPn to the listening position and the correction of the sound emission position of the sound from the speaker SPn shown in FIGS. 3 to 5 will be described in more detail with reference to FIGS. Here, an example will be described in which the speaker SPn of one other audio channel is farther from the listening position than the speaker SPr of the reference channel.
[0075]
FIG. 6 is a diagram showing the results of the processes in steps S201 to S205 shown in FIG. As shown in FIG. 6 (A), a predetermined impulse signal (test signal) is generated and emitted from two target speakers SPr and SPn, and this is picked up by a measurement microphone Mic to obtain a peak value. Ask for.
[0076]
In this case, since the distance between the speaker SPr and the speaker SPn with respect to the listening position is the case where the speaker SPn is farther as described above, as shown in FIG. The difference is called a time difference d. Here, the peak of the test signal from the speaker SPr appears as shown in FIG. 6B, and the peak of the test signal from the speaker SPn appears as shown in FIG. 6C.
[0077]
However, in this case, it is not possible to determine which of the speakers SPr and SPn is closer to or farther from the listening position. Therefore, the processing shown in FIGS. 4 and 5 is performed. FIG. 7 is a diagram showing the results of the processing of step S208 to step S212 shown in FIG.
[0078]
As described with reference to FIG. 4, the audio signal of the audio channel of the speaker SPn is delayed by time t, and the test signal is emitted through the speakers SPr and SPn. In this case, a difference of time t occurs between the output of the speaker SPn (FIG. 7A) and the output of the speaker SPr (FIG. 7B).
[0079]
Then, when the sound emitted from the test signals from the speakers SPr and SPn is picked up by the measurement microphone Mic and the peak is obtained, as shown in FIG. 7E, two peaks appear, and the difference is the time difference d1. = D + t. In this case, the peak of the test signal from the speaker SPr appears as shown in FIG. 7C, and the peak of the test signal from the speaker SPn appears as shown in FIG. 7D.
[0080]
Next, the process shown in FIG. 5 is performed. FIG. 8 is a diagram showing the results of the processing from step S214 to step S218 shown in FIG.
[0081]
As described with reference to FIG. 5, this time, the audio signal of the audio channel of the speaker SPr is delayed by time t, and the test signal is emitted through the speakers SPr and SPn. In this case, a difference of time t occurs between the output of the speaker SPn (FIG. 8A) and the output of the speaker SPr (FIG. 8B).
[0082]
Then, the sound emitted from the test signals from the speakers SPr and SPn is collected by the measurement microphone Mic, and when the peak is obtained, two peaks appear as shown in FIG. 8E, and the difference between them is the time difference d2. = Dt. In this case, the peak of the test signal from the speaker SPr appears as shown in FIG. 8C, and the peak of the test signal from the speaker SPn appears as shown in FIG. 8D.
[0083]
Thereafter, as described with reference to steps S219 to S223 in FIG. 6, the test sound from the speaker SPr and the test sound from the speaker SPn when the sound signal of the sound channel of the speaker SPn is delayed by time t. Is compared with the time difference d2 of the propagation time between the test sound from the speaker SPr and the test signal from the speaker SPn when the sound signal of the sound channel of the speaker SPr is delayed by time t. .
[0084]
In this case, since the time difference d1 when the audio signal from the speaker SPn is delayed by the time t is larger than the time difference d2 when the audio signal from the speaker SPr is delayed by the time t, it is larger than the speaker SPr. It is possible to accurately determine that the speaker SPn is far from the listening position.
[0085]
7 to 8, the case where the speaker SPn of one other audio channel is located farther from the listening position than the speaker SPr of the reference channel has been described as an example. However, when the speaker SPr of the reference channel is located farther than the speaker SPn of the other one audio channel, the time difference d2 is larger than the time difference d1, so that the speaker SPr is more than the speaker SPn. It is possible to accurately determine the distance from the listening position.
[0086]
Based on the speaker SPr, the delay amount is appropriately corrected for the sound signal of the sound channel of the speaker SPn depending on whether the speaker SPn is near or far from the listening position, and the sound is emitted from the speaker SPn. The sound to be played can be adjusted so that it is emitted from a predetermined position.
[0087]
As described above, in the case of the example shown in FIGS. 3 to 5, a distance parameter is formed for each one audio channel other than the reference channel that is sequentially changed, and the correspondence of the acoustic output device 1 is performed. However, the present invention is not limited to this. The time differences d, d1, and d2 are held for each other audio channel, and are used to convert the distance in step S106 shown in FIG. 2, and set in the delay unit 14 of the sound output device in step S107. This can be performed as described with reference to FIG.
[0088]
In addition, the measuring apparatus 2 is realized by, for example, a personal computer, but can of course be configured as a measuring apparatus dedicated machine. In this case, as shown in FIG. 1, any device including a microphone input terminal 21, a microphone amplifier 22, an A / D converter 23, and a peak detection calculation unit 24 may be used.
[0089]
In this case, the peak detection calculation unit 24 can be realized as, for example, a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. A program for performing the processing shown in FIGS. 2 and 3 to 5 is prepared in the ROM of the peak detection calculation unit 24, and the peak detection calculation unit 24 of this embodiment can be realized by executing this program. .
[0090]
[Second Embodiment]
In the first embodiment described above, an impulse signal is used as the test signal. However, in the second embodiment, in order to detect the relative position of the speaker more accurately, a noise signal such as pink noise or white noise is used as a test signal, and autocorrelation is performed. Peak detection is performed by the analysis used. Hereinafter, the second embodiment will be described.
[0091]
FIG. 9 is a block diagram for explaining the distance measurement system of the second embodiment formed by applying the distance measurement correction system according to the present invention. In the distance measurement system according to the second embodiment, the same reference numerals are given to the same components as those in the distance measurement system according to the first embodiment shown in FIG. Is omitted.
[0092]
The distance measurement correction system according to the second embodiment is similar to the distance measurement correction system according to the first embodiment shown in FIG. 1 having the acoustic output device 1 and the measurement device 2. , An acoustic output device 1 and a measuring device 3. Also in the second embodiment, the sound output device 1 and the measurement device 3 are connected by RC232-C or USB so that the sound output device 1 can be controlled from the measurement device 3.
[0093]
Also in the second embodiment, the sound output device 1 is configured in substantially the same manner as the sound output device 1 of the first embodiment described above, and is an audio signal encoded with 5.1 channels. Can be processed, and is provided with 5.1 channels (six channels) of audio channels.
[0094]
However, the test signal generator 17 of the sound output device 1 of the second embodiment does not generate a predetermined impulse signal as a test signal, but generates and outputs a noise signal that continues for a certain period of time. In the second embodiment, for example, pink noise is generated and output.
[0095]
The measurement apparatus 3 includes the microphone terminal 31, the microphone amplifier 32, and the A / D converter 33, as with the measurement apparatus 2 of the first embodiment described above. However, the measurement apparatus 3 of the second embodiment is different from the measurement apparatus 2 of the first embodiment described above in that the autocorrelation function calculation unit 34 is provided.
[0096]
In the distance measurement correction system according to the second embodiment, as in the case of the distance measurement correction system according to the first embodiment, a predetermined audio channel of 5.1 channels is used as a reference channel (reference channel). And the relative distance to the listening point for the speaker of the reference channel and the speaker of the other audio channel is measured, and based on the measurement result, the other audio channel of the other audio channel is measured. By correcting (adjusting) the delay amount with respect to the audio signal, the sound output position of the sound output from the speaker is corrected.
[0097]
Then, without changing the reference channel, the other one audio channel is sequentially changed to measure the relative distance between the reference channel speaker and the other one audio channel speaker with respect to the listening point, Based on the measurement result, the delay amount of the audio signal of all audio channels is corrected, and the sound emission position of the sound emitted from the speaker connected to each audio channel is corrected.
[0098]
As a result, the sound emission position of the sound emitted from the speakers of all other sound channels is corrected with reference to the reference channel, and a good listening environment for the sound at the listening position can be prepared. .
[0099]
As described above, the distance measurement correction system according to the second embodiment operates in the same manner as the distance measurement correction system according to the first embodiment. When the test sound emitted from the speakers connected to the two sound channels is collected and a peak is detected from the collected sound, the autocorrelation of the collected sound is used.
[0100]
More specifically, the distance measurement correction system of the second embodiment also performs the operation of the flowchart of FIG. 2 shown as an explanation of the operation of the distance measurement correction system of the first embodiment. It is something that can be done. And the process performed in each step of step S101-step S105 shown in FIG. 2 turns into a process using an autocorrelation so that it may demonstrate below.
[0101]
In the second embodiment described below, as in the case of the first embodiment described above, the speaker connected to the reference channel is referred to as a speaker SPr and is paired with the reference channel. A speaker connected to one audio channel is referred to as a speaker SPn. The same applies to FIGS.
[0102]
Also in the distance measurement correction system of the second embodiment, as in the case of the first embodiment described above, the audio channel connected to the center speaker (C) SP3 is used as a reference channel, The speaker positions of other audio channels are compared.
[0103]
10 to 12, as described above, when the distance measurement correction system of the second embodiment performs the distance measurement correction process for each speaker as in the flowchart shown in FIG. 2, step S <b> 101 is performed. The process executed in each step of Step S105 and corresponding to the flowcharts shown in FIGS. 3 to 5 described as the operation of the distance measurement correction system of the first embodiment.
[0104]
In the flowcharts of FIGS. 10 to 12, the same reference numerals (step numbers) are given to portions that are performed in the same manner as the processes of the flowcharts illustrated in FIGS. 3 to 5, and descriptions thereof are omitted.
[0105]
And the flowchart of FIG. 10 for demonstrating operation | movement of the distance measurement correction system of this 2nd Embodiment, and the figure for demonstrating operation | movement of the distance measurement correction | amendment system of 1st Embodiment corresponding to this. As can be seen from comparison with the flowchart of FIG. 3, each step other than step S304 in FIG. 10 and step S204 in FIG. 3 is the same process.
[0106]
Further, the flowchart of FIG. 11 for explaining the operation of the distance measurement correction system of the second embodiment and the diagram for explaining the operation of the distance measurement correction system of the first embodiment corresponding thereto. As can be seen from comparison with the flowchart of FIG. 4, each step other than step S311 in FIG. 11 and step S211 in FIG.
[0107]
Similarly, the flowchart of FIG. 12 for explaining the operation of the distance measurement correction system of the second embodiment and the operation of the distance measurement correction system of the first embodiment corresponding to the flowchart of FIG. As can be seen by comparing with the flowchart of FIG. 5, each step other than step S317 in FIG. 12 and step S217 in FIG. 3 is exactly the same processing.
[0108]
That is, also in the distance measurement correction system of the second embodiment, the delay amount of the audio signal is made the same for the reference channel selected as the processing target and the other audio channel by the processing shown in FIG. Then, the test voice corresponding to the test signal is emitted, and the time difference d of the voice propagation time is obtained.
[0109]
Next, with the processing shown in FIG. 11, the delay time of the other one audio channel that is not the reference channel is delayed by time t, and the reference channel selected as the processing target and the other audio channel are selected. Then, the test voice corresponding to the test signal is emitted to obtain the time difference d1 of the voice propagation time.
[0110]
Next, by the processing shown in FIG. 12, the delay time of the reference channel is delayed by time t, the delay time of one other audio channel is returned to the base, and the reference channel selected as the processing target and the other 1 The time difference d2 of the sound propagation time is obtained by emitting test sound according to the test signal for the two sound channels.
[0111]
Then, from the magnitude relationship between the time difference d1 and the time difference d2, the difference between the sound propagation time from the speaker SPr of the reference channel with respect to the listening position and the sound propagation time from the speaker SPn of the other one sound channel is obtained. , Grasp the relative distance (positional relationship) between the speaker SPr and the speaker SPn with respect to the listening position, correct the delay amount of the audio signal in the other audio channel, and from the speaker of the other audio channel The sound emission position of the emitted sound is corrected to an appropriate position.
[0112]
Then, in any of the processing in step S304 in FIG. 10, the processing in step S311 in FIG. 11, and the processing in step S317 in FIG. 12, from the measurement microphone Mic, as described below, The peak value is calculated based on the autocorrelation of the collected sound signal.
[0113]
Hereinafter, the peak detection processing of the collected sound signal using the autocorrelation performed similarly in step S304 of FIG. 10, step S311 of FIG. 11, and step S317 of FIG. 12 will be described. This process is a process mainly performed in the autocorrelation function calculation unit 34 of the measurement apparatus 3 of the distance measurement correction system according to the second embodiment.
[0114]
The autocorrelation function calculation unit 34 of the measuring device 3 first collects the collected sound signal collected by the measurement microphone Mic, amplified by the microphone amplifier 32, and converted into a digital signal by the A / D converter 33 (1). A time domain signal is converted to a frequency domain signal by performing FFT (Fast Fourier Transform).
[0115]
Next, (2) the power spectrum (frequency spectrum) is obtained from the collected sound signal converted into the frequency domain signal, and (3) the average of the obtained power spectrum is subjected to inverse FFT to obtain the autocorrelation of the collected sound signal. Ask. (4) Peaks are detected for data excluding the first autocorrelation (position 0 (zero)). (5) Based on the detected peak, as in the case of the first embodiment described above, the time difference between the propagation times of the test sounds emitted from the speakers of the two audio channels to be processed d, d1, and d2 are obtained.
[0116]
The processing of (1) to (5) is performed in step S304 shown in FIG. 10, step S311 shown in FIG. 11, and step S317 shown in FIG. It is possible to reliably and accurately grasp the positional relationship between the two speakers connected to the listening position.
[0117]
Then, a delay amount with respect to the audio signal of one audio channel other than the reference channel is generated as a distance parameter, and this is generated as a corresponding delay circuit among the delay circuits 141 to 146 constituting the delay unit 14 of the acoustic output device 1. By setting to, the sound emission position of the sound emitted from the speaker connected to the sound channel can be corrected to an appropriate position.
[0118]
By performing this process for all other audio channels without changing the reference channel, the sound emission position from the speakers connected to all other audio channels other than the reference channel is adjusted appropriately, and listening is performed. A good listening environment for the reproduced sound in the position can be prepared.
[0119]
Here, measurement of the relative distance between the speaker SPr of the reference channel and the speaker SPn of the other one audio channel with respect to the listening position shown in FIGS. 10 to 12, and the sound emission position of the sound emitted from the speaker SPn. The correction will be described in more detail with reference to FIGS. Here, an example will be described in which the speaker SPn of one other audio channel is farther from the listening position than the speaker SPr of the reference channel.
[0120]
FIG. 13 is a diagram showing the results of the processes in steps S201 to S205 including step S304 as shown in FIG. As shown in FIG. 13A, a predetermined noise signal (test signal) is generated, emitted from two speakers SPr and SPn to be measured, collected by a measurement microphone Mic, and peaked. Find the value.
[0121]
In this case, since the distance between the speaker SPr and the speaker SPn with respect to the listening position is the case where the speaker SPn is farther as described above, the test sound emitted from the speaker SPr and captured by the measurement microphone Mic is used. FIG. 13B shows the test sound emitted from the speaker SPn and captured by the measurement microphone Mic, as shown in FIG. 13C.
[0122]
Therefore, the test sound captured by the measurement microphone Mic is actually a signal obtained by combining FIG. 13B and FIG. 13C as shown in FIG.
[0123]
The collected sound signal shown in FIG. 13 (D) is subjected to FFT, a power spectrum is obtained as shown in FIG. 13 (E), and the average of the power spectrum is subjected to inverse FFT, as shown in FIG. 13 (F). In addition, the autocorrelation is obtained, and the peak value can be detected. From the detected peak value, a time difference d between the propagation times of the test sound emitted from the speaker SPr and the test sound emitted from the speaker SPn is obtained.
[0124]
However, in this case, it is not possible to determine which of the speakers SPr and SPn is closer to or farther from the listening position. Therefore, the processing shown in FIGS. 11 and 12 is performed. FIG. 14 is a diagram showing the results of the processing in steps S208 to S212 including step S311 shown in FIG.
[0125]
Here, as described with reference to FIG. 4 in the first embodiment, the audio signal of the audio channel of the speaker SPn is delayed by time t, and the test signal is released through the speakers SPr and SPn. Make a sound. In this case, a difference of time t occurs between the output of the speaker SPn (FIG. 14A) and the output of the speaker SPr (FIG. 14B).
[0126]
In this case, the test sound emitted from the speaker SPr and captured by the measurement microphone Mic is as shown in FIG. 14C, and the test sound emitted from the speaker SPn and captured by the measurement microphone Mic is As shown in FIG.
[0127]
Therefore, the test sound captured by the measurement microphone Mic is actually a signal obtained by combining FIG. 14C and FIG. 14D as shown in FIG.
[0128]
The collected sound signal shown in FIG. 14 (E) is subjected to FFT, a power spectrum is obtained as shown in FIG. 14 (F), and the average of the power spectrum is subjected to inverse FFT, as shown in FIG. 14 (G). In addition, the autocorrelation is obtained, and the peak value can be detected. Then, from the detected peak value, a time difference d1 = d + t between the propagation times of the test sound emitted from the speaker SPr and the test sound emitted from the speaker SPn is obtained.
[0129]
Next, the process shown in FIG. 12 is performed. FIG. 15 is a diagram showing the results of the processes in steps S214 to S218 including step S317 shown in FIG.
[0130]
In the first embodiment described above, as described with reference to FIG. 5, this time, the audio signal of the audio channel of the speaker SPr is delayed by time t, and the test signal is released through the speakers SPr and SPn. Make a sound. In this case, a difference of time t occurs between the output of the speaker SPn (FIG. 15A) and the output of the speaker SPr (FIG. 15B).
[0131]
In this case, the test sound emitted from the speaker SPr and captured by the measurement microphone Mic is as shown in FIG. 15C, and the test sound emitted from the speaker SPn and captured by the measurement microphone Mic is As shown in FIG.
[0132]
Therefore, the test sound captured by the measurement microphone Mic is actually a signal obtained by combining FIG. 15C and FIG. 15D, as shown in FIG.
[0133]
The collected sound signal shown in FIG. 15 (E) is subjected to FFT, a power spectrum is obtained as shown in FIG. 15 (F), and the average of the power spectrum is subjected to inverse FFT, as shown in FIG. 15 (G). In addition, the autocorrelation is obtained, and the peak value can be detected. Then, from the detected peak value, a time difference d2 = absolute value [dt] between the propagation time of the test sound emitted from the speaker SPr and the test sound emitted from the speaker SPn is obtained.
[0134]
Thereafter, the processing of step S219 to step S223 in FIG. 12 is performed, and the test sound from the speaker SPr and the test sound from the speaker SPn when the sound signal of the sound channel of the speaker SPn is delayed by time t Is compared with the time difference d2 of the propagation time between the test sound from the speaker SPr and the test signal from the speaker SPn when the sound signal of the sound channel of the speaker SPr is delayed by time t.
[0135]
In this case, as shown in FIG. 14G and FIG. 15H, the time difference d1 obtained in step S212 of the process shown in FIG. 11 is shown in FIG. Thus, it can be seen that the speaker SPn is farther from the listening position than the speaker SPr of the reference channel.
[0136]
In FIGS. 13 to 15, the case where the speaker SPn of one other audio channel is located farther from the listening position than the speaker SPr of the reference channel has been described as an example. However, when the speaker SPr of the reference channel is located farther than the speaker SPn of the other one audio channel, the time difference d2 is larger than the time difference d1, so that the speaker SPr is more than the speaker SPn. It is possible to accurately determine the distance from the listening position.
[0137]
Then, at the listening position, the time difference d, which is the difference between the propagation time of the emitted sound from the speaker SPr of the reference channel and the propagation time of the emitted sound from the speaker SPn of the other one audio channel, and the listening position Thus, a distance parameter is formed so as to adjust the delay amount of the audio signal of the other audio channel in accordance with the determination result of whether or not it is far from the speaker of the reference channel.
[0138]
By setting the formed distance parameter in the corresponding delay circuit of the delay unit 14 of the sound output device 1, the sound emission position of the sound emission sound emitted from the speaker SPn of the other one audio channel is appropriately set. The position can be adjusted. As described above, this processing is performed by sequentially changing the other one audio channel without changing the reference channel, so that a favorable listening environment for the reproduced sound at the listening position can be prepared. Is done.
[0139]
[Removing influences such as reflected sound]
In the case of the distance measurement correction system according to the second embodiment, the autocorrelation of the test sound emitted from each speaker is obtained in advance, and this is used to influence the reflected sound or the like. It is possible to prevent.
[0140]
That is, in the case of the second embodiment, the test sound corresponding to the test signal is emitted for each speaker connected to each of the 5.1 audio channels, and the autocorrelation (the self-correlation of each speaker). (Correlation).
[0141]
As described in detail in the second embodiment, the test sound corresponding to the test signal is simultaneously emitted from the speakers of the two audio channels to be measured, and the self of the test sound from the two speakers is emitted. In this case, the autocorrelation of the test sound from the two speakers is compared with the autocorrelation obtained in advance for each of the two speakers to be measured.
[0142]
As a result of this comparison, the autocorrelation of each speaker obtained in advance approximated by the autocorrelation of the test sound from the two speakers is subtracted from the autocorrelation of the test sound from the two speakers. Is used as the autocorrelation of the test sound from the two speakers that are the objects of measurement.
[0143]
By doing so, the autocorrelation obtained for each speaker is the autocorrelation of the test sound (sound pickup signal) including the reflected sound from the wall or the like at the site, and the two speakers to be measured Similarly, the auto-correlation of the test sound from, also includes components such as reflected sound, so this is effectively canceled and the relative positional relationship between the two speakers to be measured and the distance difference (time difference) Can be measured accurately.
[0144]
The autocorrelation of each speaker is obtained by emitting a test sound for each speaker, picking up the sound with a microphone for measurement Mic, and calculating each of FFT → power spectrum calculation → inverse FFT in the autocorrelation function calculator 34. It can be obtained by processing.
[0145]
The autocorrelation of each loudspeaker thus obtained is stored and held in a non-volatile memory such as an EEPROM (Electrically Erasable and Programmable ROM) provided in the autocorrelation function calculator 34 or in the measuring device 3, for example. To leave. The autocorrelation comparison and subtraction operation described above is performed in the autocorrelation function calculation unit 34. In this case, the autocorrelation of each speaker stored and held in a nonvolatile memory such as an EEPROM is referred to. What should I do?
[0146]
In the second embodiment, the measuring device 3 can be configured by a personal computer, for example, as in the case of the measuring device 2 of the first embodiment described above.
[0147]
Of course, it is also possible to configure a dedicated measuring device including the microphone input terminal 31, the microphone amplifier 32, the A / D converter 33, and the autocorrelation function calculator 34. In this case, the autocorrelation function calculation unit 34 can be realized as a microcomputer including a CPU, a ROM, a RAM, and the like, for example, similarly to the peak detection calculation unit 24 of the first embodiment. A program for performing the processing shown in FIGS. 2 and 10 to 12 is prepared in the ROM of the autocorrelation calculation unit 34, and the autocorrelation function calculation unit 34 according to this embodiment is realized by executing the program. it can.
[0148]
In order to remove the influence of reflected sound and the like, the comparison process between the autocorrelation of the test sound from the two speakers to be measured and the individual autocorrelation of the two speakers to be measured and the result of the comparison Based on the autocorrelation of the test speech from the two speakers to be measured, the one that approximates the autocorrelation of the test speech from the two speakers to be measured is subtracted from the autocorrelation of the two speakers to be measured. This can be realized by preparing a program for processing in the ROM of the autocorrelation calculation unit 34 and executing it.
[0149]
[Other configuration examples of the first and second embodiments]
In the first embodiment described above, the test signal generator 16 is provided in the sound output device 1. However, it is not limited to this. The test signal generator 16 may be provided on the measurement device 2 side, and the test signal may be supplied from the measurement device 2 to the sound output device 1 through an analog signal line or a digital signal line. Of course, the test signal generator 16 may be provided separately from the sound output device 1 and the measurement device 2.
[0150]
Similarly, in the second embodiment described above, the test signal generator 17 is provided in the sound output device 1. However, it is not limited to this. The test signal generator 17 may be provided on the measurement device 3 side, and the test signal may be supplied from the measurement device 3 to the sound output device 1 through an analog signal line or a digital signal line. Of course, the test signal generator 17 may be provided separately from the sound output device 1 and the measurement device 3.
[0151]
Further, in the first and second embodiments described above, the measuring devices 2 and 3 control the switch unit 13 of the sound output device 1 so that the measurement target, the reference channel, and another audio channel 2 Although one audio channel is selected, the present invention is not limited to this.
[0152]
For example, the audio channel serving as the reference channel is determined in advance, and the switching order of the audio channel serving as the other one channel is determined in advance, thereby controlling the switching of the switch unit 13 on the acoustic output device 1 side. You may do it.
[0153]
In the first and second embodiments described above, when the audio signals of the two audio channels to be measured are delayed in advance by time t, the sound output device 1 is controlled by the control signal from the measurement device 2. Although described as what is controlled, it is not restricted to this, It can also control to adjust automatically at the sound output device 1 side.
[0154]
In the first and second embodiments described above, the sound output device 1, the measurement device 2, and the measurement device 3 have been described as separate devices, but the present invention is not limited to this. Absent. A sound output measuring device (distance measurement correcting device) in which the sound output device 1 and the measuring device 2 are integrated can be formed, and the sound output measuring device in which the sound output device 1 and the measuring device 3 are integrated. (Distance measurement correction apparatus) can also be formed.
[0155]
In the first and second embodiments described above, as shown in FIGS. 1 and 9, the peak detection calculation unit 24 of the measurement device 2 or the autocorrelation function calculation unit 34 of the measurement device 3 is provided. Although described in the form of directly controlling the switch unit 13 and the delay unit 14 of the sound output device 1, it is not limited thereto.
[0156]
That is, when the sound output device 1 and the measurement devices 2 and 3 are separate, information such as a control signal distance parameter from the measurement devices 2 and 3 is transmitted to a control unit (not shown) of the sound output device 1 and the sound is output. It goes without saying that the control unit of the output device 1 may control each unit of the own device, that is, each switch circuit of the switch unit 13 and each delay circuit of the delay unit 14.
[0157]
[Another example of the measurement procedure of the first and second embodiments]
In the first and second embodiments described above, the audio signals of the two audio channels to be measured are first measured (1) with the same delay amount, and (2) one of the audio signals is then measured. The delay amount of the channel is measured after being delayed by a predetermined time t, and (3) the delay amount of the one audio channel is returned to the original, and the delay amount of the other audio channel is delayed by the predetermined time t. The measurement between three stages was performed. However, it is not limited to this.
[0158]
For example, only one audio channel may be measured a plurality of times by changing the delay amount a plurality of times. Specifically, first, (1) the delay amount is measured to obtain the time difference d of the propagation time, and (2) the delay amount of one voice channel is then delayed by a predetermined time t, and then measured. A time difference d1 of the propagation time is obtained; and (3) the delay amount of the one voice channel is measured after being delayed by a predetermined time t1 longer than the predetermined time t to obtain a time difference d2 of the propagation time, and the time difference d, The relative positions of the two speakers can be determined depending on whether d1 and d2 are increased or decreased.
[0159]
That is, even if the measurement is not performed by changing the respective delay amounts of the two audio channels to be measured, the delay amount is set to be multiple times (at least twice) for one audio channel of the two audio channels to be measured. ) By changing the measurement, it is possible to know the relative positions of the two speakers to be measured.
[0160]
[Another example of the test signal of the first embodiment]
In the first embodiment described above, the so-called impulse signal is used as the test signal. However, the present invention is not limited to this. The test signal may be a pulse signal having various shapes. FIG. 16 is a diagram for explaining another example of the test signal.
[0161]
For example, as shown in FIG. 16A, the energy of the test signal can be increased by using a pulse signal in which a positive polarity signal and a negative polarity signal are continuous, and accurate measurement of the assumed positions of the two speakers can be accurately performed. Can be made to do. Further, as shown in FIG. 16B, by using a pulse signal having a shape in which the sum of the area of the portion indicated by symbol a and the area of the portion indicated by symbol c matches the area of the portion indicated by symbol b. Thus, it is possible to accurately measure the assumed positions of the two speakers without being influenced by the DC component included in the test signal.
[0162]
Further, as shown in FIG. 16C, test signals (pulse signals) having different polarities are output from the speakers of the two audio channels to be measured. That is, of the two audio channel speakers to be measured, for example, from the reference channel speaker, a positive pulse signal as shown in FIG. 16C (a) and from the other one audio channel speaker. The negative pulse signals as shown in FIG. 16C (B) are output simultaneously.
[0163]
The difference between the positive polarity peak and the negative polarity peak is the time difference d of the propagation time, and by determining which polarity peak is the data first, the position of the two speakers to be measured relative to the listening position You can also grasp the relationship. Therefore, in this case, the time difference d and the relative positional relationship between the two speakers can be grasped by one measurement without changing the delay time of the audio channel.
[0164]
Also, as shown in FIG. 16D, two so-called non-harmonic signals whose cycles are not in an integer multiple relationship may be used as the test signal. In this case, two unharmonic signals, for example, the signal shown in FIG. 16D (A) and the signal shown in FIG. 16D (B) are supplied to the speakers of the two audio channels to be measured, Try to emit test audio. By doing so, the phase difference between the test sounds emitted from the two speakers to be measured can be detected, and the delay amount can be calculated from the phase difference.
[0165]
That is, it is possible to use various signals that can pick up the sound emission signals emitted from two or more speakers and detect the difference in peak or phase difference as the test signals.
[0166]
In addition to the examples described above, for example, TDS (Time Delay Spectrometry: Rife, Douglas D. and Vanderkooy, John; "Transfer-Function Measurement with Maximum-Length Sequences," J. Audio Eng. Soc., Vol. 37, No. 6, Jun. 1989, pp. 419-442) may be used to measure the relative position of the two speakers to be measured with respect to the listening position.
[0167]
In the first and second embodiments described above, the audio channel connected to the center speaker (C) SP3 is used as a reference channel. However, the present invention is not limited to this, and it is connected to another speaker. It is of course possible to use the selected audio channel as a reference channel.
[0168]
In addition, when the distance from each speaker to the listening point varies greatly, a plurality of other audio channels of one speaker are set, a reference channel speaker, and a plurality of other audio channel speakers. It is also possible to detect the relative distance between the reference channel speaker and a plurality of other audio channel speakers with respect to the listening position.
[0169]
In this case, the process of measuring the distance by delaying by the predetermined time t is performed for each channel, or the audio signal of the reference channel is not delayed for the predetermined time t, It is possible to measure the relative distance by delaying the audio signal of one audio channel by a predetermined time t.
[0170]
Further, the functions of the measuring devices 2 and 3 described above can be provided to a server device provided on a public communication network such as the Internet or a local area network. Then, a collected sound signal (measurement signal) collected by the measurement microphone Mic is temporarily stored, for example, and transmitted to the server device through a predetermined network. The server device processes (analyzes) the received sound pickup signal to determine the relative distance and positional relationship of the speaker with respect to the listening point, forms a distance parameter, and returns this to the sound output device through the network. You can also do it.
[0171]
In this case, instead of the measurement devices 2 and 3, the collected sound signal from the measurement microphone Mic is stored and transmitted, and transmitted to the target server device, and the distance parameter returned from the server device is set. A communication device that receives and supplies the sound to the sound output device 1 may be separately received, or such a communication function may be provided in the sound output device 1.
[0172]
That is, the measuring devices 2 and 3 are not limited to those placed in the vicinity of the sound output device 1, and may be provided on a public communication network or a local area network.
[0173]
In addition to the AV amplifier device, the multi-channel sound output device 1 may be various electronic devices that output multi-channel sound, such as a multi-channel sound playback device such as a DVD player. That is, the present invention can be applied to various acoustic output devices that output multi-channel audio.
[0174]
【The invention's effect】
As described above, according to the present invention, the relative position between the speaker of the reference channel and the speaker of the other audio channel is determined by using only the collected sound signal collected by the measurement microphone without using the reference signal. And the sound emission position of the sound emitted from the speakers of the other sound channels can be adjusted.
[0175]
Therefore, the relative position of each audio channel with respect to the reference channel is obtained with a relatively simple configuration without complicating the system and each device, and the sound output position of the sound output from the speaker is adjusted. can do.
[Brief description of the drawings]
FIG. 1 is a block diagram for explaining a distance measurement correction system to which an embodiment of a distance measurement correction system according to the present invention is applied.
FIG. 2 is a flowchart for explaining distance measurement and correction processing performed in the distance measurement correction system shown in FIG. 1;
FIG. 3 is a flowchart for explaining processing performed in steps S101 to S105 of the flowchart shown in FIG. 2;
FIG. 4 is a flowchart following FIG. 3;
FIG. 5 is a flowchart following FIG. 4;
6 is a diagram for specifically explaining an example of processing of the flowcharts shown in FIGS. 3 to 5; FIG.
FIG. 7 is a diagram for specifically explaining an example of processing of the flowcharts shown in FIGS. 3 to 5;
FIG. 8 is a diagram for specifically explaining an example of processing of the flowcharts shown in FIGS. 3 to 5;
FIG. 9 is a block diagram for explaining another example of a distance measurement correction system to which an embodiment of a distance measurement correction system according to the present invention is applied.
10 is a flowchart for explaining processing performed in the distance measurement correction system shown in FIG. 9;
FIG. 11 is a flowchart following FIG. 10;
FIG. 12 is a flowchart following FIG. 11;
FIG. 13 is a diagram for specifically explaining an example of processing of the flowcharts shown in FIGS. 10 to 12;
14 is a diagram for specifically explaining an example of processing of the flowcharts shown in FIGS. 10 to 12; FIG.
FIG. 15 is a diagram for specifically explaining an example of processing of the flowcharts illustrated in FIGS. 10 to 12;
FIG. 16 is a diagram for explaining another example of a test signal.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Sound output device, 11 ... Input terminal, 12 ... Decoder, 13 ... Switch part, 131-136 ... Switch circuit, 14 ... Delay part, 141-146 ... Delay circuit, 15 ... Amplifier part, 151-156 ... Amplifier circuit DESCRIPTION OF SYMBOLS 2, 3 ... Measurement apparatus, 21, 31 ... Microphone terminal, 22, 32 ... Microphone amplifier, 23, 33 ... A / D converter, 24 ... Peak detection calculation part, 34 ... Autocorrelation function calculation part, SP1-SP6 ... Speaker, Mic ... Microphone for measurement

Claims (30)

Distance measurement of a speaker connected to each of the plurality of sound channels of the sound output device by receiving the collected sound from a sound output device having a plurality of sound channels and a microphone arranged at a listening position A distance measurement correction system comprising a measurement device for performing
The acoustic output device is
Select a reference audio channel and another audio channel, and output a test signal that has a predetermined shape through the selected audio channel and that has a different polarity between the reference audio channel and the other audio channel And switching means for switching the other audio channel to another audio channel every predetermined period;
A delay unit that receives a distance parameter from the measurement device and controls a delay time of an audio signal for each of the plurality of audio channels;
The measuring device is
The relative distance of the measurement target speaker with respect to the listening position is determined based on a measurement signal including the sound from the speaker of the reference sound channel and the sound from the speaker of the other sound channel collected by the microphone. A distance measuring means,
A distance measuring correction system comprising: a parameter forming unit configured to form a distance parameter for the other audio channel based on a measurement result of the distance measuring unit and to supply the parameter to the acoustic output device. . The distance measurement correction system according to claim 1,
The sound output device determines whether the speaker connected to the reference audio channel or the speaker connected to the other audio channel is closer to the listening position within the predetermined period. Change means for changing the delay time of one of the audio signals among the other audio channels a plurality of times , or changing the delay time of the audio signal one channel at a time for both audio channels A distance measurement correction system comprising: The distance measurement correction system according to claim 1,
The measuring device is
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the delay unit of the sound output device is controlled to control the predetermined period. A control signal for changing a delay time of one audio signal of the reference audio channel and the other audio channel a plurality of times , or 1 for both channels. forming a control signal for so as to vary the delay time of the audio signal by the channel, the distance measurement correction system characterized in that it comprises a delay control means so as to supply to the audio output device. A distance measurement correction system according to claim 1, claim 2 or claim 3,
The measuring device is
A distance measurement correction system comprising test signal generation means for generating the test signal and supplying the test signal to the sound output device. Distance measurement of a speaker connected to each of the plurality of sound channels of the sound output device by receiving the collected sound from a sound output device having a plurality of sound channels and a microphone arranged at a listening position A distance measurement correction system comprising a measurement device for performing
The acoustic output device is
A reference audio channel and another audio channel are selected, and through the selected audio channel, a test signal of one frequency out of the two frequency test signals in an unharmonious relationship is output from the reference audio channel, and the other Switching means for outputting a test signal of the frequency of the other audio channel from the other audio channel and switching the other audio channel to another audio channel every predetermined period;
A delay unit that receives a distance parameter from the measurement device and controls a delay time of an audio signal for each of the plurality of audio channels;
The measuring device is
The relative distance of the measurement target speaker with respect to the listening position is determined based on a measurement signal including the sound from the speaker of the reference sound channel and the sound from the speaker of the other sound channel collected by the microphone. A distance measuring means,
A distance measuring correction system comprising: a parameter forming unit configured to form a distance parameter for the other audio channel based on a measurement result of the distance measuring unit and to supply the parameter to the acoustic output device. . The distance measurement correction system according to claim 5 ,
The sound output device determines whether the speaker connected to the reference audio channel or the speaker connected to the other audio channel is closer to the listening position within the predetermined period. Change means for changing the delay time of one of the audio signals among the other audio channels a plurality of times , or changing the delay time of the audio signal one channel at a time for both audio channels A distance measurement correction system comprising: The distance measurement correction system according to claim 5 ,
The measuring device is
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the delay unit of the sound output device is controlled to control the predetermined period. A control signal for changing a delay time of one audio signal of the reference audio channel and the other audio channel a plurality of times , or 1 for both channels. forming a control signal for so as to vary the delay time of the audio signal by the channel, the distance measurement correction system characterized in that it comprises a delay control means so as to supply to the audio output device. A distance measurement correction system according to claim 5, claim 6 or claim 7 ,
The measuring device is
A distance measurement correction system comprising test signal generation means for generating the test signal and supplying the test signal to the sound output device. Distance measurement of a speaker connected to each of the plurality of sound channels of the sound output device by receiving the collected sound from a sound output device having a plurality of sound channels and a microphone arranged at a listening position A distance measurement correction system comprising a measurement device for performing
The acoustic output device is
A reference audio channel and another audio channel are selected, and a test signal that is a random noise signal is output through the selected audio channel, and the other audio channel is changed to another audio channel every predetermined period. Switching means for switching, and
A delay unit that receives a distance parameter from the measurement device and controls a delay time of an audio signal for each of the plurality of audio channels;
The measuring device is
By using the autocorrelation about the measurement signal and a voice from the voice and the other audio channel loudspeaker from the reference speech channel speaker picked up by the microphone, measurement of the corresponding loudspeaker relative with respect to the listening position A distance measuring means for determining a specific distance;
A distance measuring correction system comprising: a parameter forming unit configured to form a distance parameter for the other audio channel based on a measurement result of the distance measuring unit and to supply the parameter to the acoustic output device. . A distance measurement correction system according to claim 9 ,
The sound output device determines whether the speaker connected to the reference audio channel or the speaker connected to the other audio channel is closer to the listening position within the predetermined period. Change means for changing the delay time of one of the audio signals among the other audio channels a plurality of times , or changing the delay time of the audio signal one channel at a time for both audio channels A distance measurement correction system comprising: A distance measurement correction system according to claim 9 ,
The measuring device is
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the delay unit of the sound output device is controlled to control the predetermined period. A control signal for changing a delay time of one audio signal of the reference audio channel and the other audio channel a plurality of times , or 1 for both channels. forming a control signal for so as to vary the delay time of the audio signal by the channel, the distance measurement correction system characterized in that it comprises a delay control means so as to supply to the audio output device. 9., A distance measurement correction system of claim 10 or claim 11,
The measuring device is
A distance measurement correction system comprising test signal generation means for generating the test signal and supplying the test signal to the sound output device. A distance measurement correction system according to claim 9, claim 10, claim 11 or claim 12 ,
The distance measuring means includes
Means for performing a fast Fourier transform on the measurement signal a predetermined number of times;
Means for obtaining an average of the power spectrum of the measurement signal subjected to fast Fourier transform;
Means for obtaining an autocorrelation of an audio signal from the object to be measured by performing inverse fast Fourier transform on the average of the power spectrum;
A distance measurement correction system comprising: means for detecting a peak from the obtained autocorrelation, and obtaining a relative distance with respect to the listening position for the speaker to be measured. A plurality of audio channels are provided, and the distance parameter is formed and supplied to an acoustic output device capable of controlling the delay time of the audio signal for each of the plurality of audio channels according to the supplied distance parameter. A distance measuring device,
The acoustic output device selects a reference audio channel and another audio channel, and is a pulse signal having a predetermined shape through the selected audio channel, and the reference audio channel and the other audio channel have a polarity. A different test signal is output, and the other audio channel can be switched to another audio channel every predetermined period.
Based on the measurement signal including the sound from the speaker of the reference sound channel and the sound from the speaker of the other sound channel picked up by the microphone arranged at the listening position, the relative of the speaker to be measured with respect to the listening position A distance measuring means for determining a specific distance;
The distance based on the measurement result measuring means, to form a distance parameter for the other audio channel, the distance measuring device, characterized in that it comprises a parameter forming means so as to supply to the acoustic output device the same. The distance measuring device according to claim 14 ,
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the sound output device is controlled, and within the predetermined period, A control signal for changing the delay time of one of the audio signals of the reference audio channel and the other audio channel a plurality of times is formed , or one audio signal of both audio channels forming a control signal for the to change the delay time, the distance measuring device, characterized in that it comprises a delay control means so as to supply to the audio output device. The distance measuring device according to claim 14 or 15 ,
A distance measuring device comprising test signal generating means for generating the test signal and supplying the test signal to the sound output device. A plurality of audio channels are provided, and the distance parameter is formed and supplied to an acoustic output device capable of controlling the delay time of the audio signal for each of the plurality of audio channels according to the supplied distance parameter. A distance measuring device,
The acoustic output device selects a reference audio channel and another audio channel, and transmits a test signal of one frequency out of two frequency test signals in an unharmonic relationship through the selected audio channel. Output from the channel, the test signal of the other frequency is output from the other audio channel, and the other audio channel can be switched to another audio channel every predetermined period,
Based on the measurement signal including the sound from the speaker of the reference sound channel and the sound from the speaker of the other sound channel picked up by the microphone arranged at the listening position, the relative of the speaker to be measured with respect to the listening position A distance measuring means for determining a specific distance;
A distance measuring device comprising: a parameter forming unit configured to form a distance parameter for the other audio channel based on a measurement result of the distance measuring unit and to supply the parameter to the sound output device. The distance measuring device according to claim 17 ,
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the sound output device is controlled, and within the predetermined period, A control signal for changing the delay time of one audio signal of the reference audio channel and the other audio channel a plurality of times is formed, or the audio signal of each audio channel is one channel at a time. A distance measuring device comprising delay control means for forming a control signal for changing a delay time and supplying the control signal to the sound output device. The distance measuring device according to claim 17 or 18 ,
A distance measuring device comprising test signal generating means for generating the test signal and supplying the test signal to the sound output device. A plurality of audio channels are provided, and the distance parameter is formed and supplied to an acoustic output device capable of controlling the delay time of the audio signal for each of the plurality of audio channels according to the supplied distance parameter. A distance measuring device,
The acoustic output device selects a reference audio channel and another audio channel, outputs a test signal that is a random noise signal through the selected audio channel , and outputs the other audio channel at predetermined intervals. Can be switched to another audio channel,
By using the autocorrelation about the measurement signal including a voice from the reference speech channel speaker picked up by a microphone arranged in the listening position and sound from the other audio channel speaker, measurements for listening position Distance measuring means for determining a relative distance of the target speaker;
The distance based on the measurement result measuring means, to form a distance parameter for the other audio channel, the distance measuring device, characterized in that it comprises a parameter forming means so as to supply to the acoustic output device the same. The distance measuring device according to claim 20 ,
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the sound output device is controlled, and within the predetermined period, A control signal for changing the delay time of one of the audio signals of the reference audio channel and the other audio channel a plurality of times is formed , or one audio signal of both audio channels forming a control signal for the to change the delay time, the distance measuring device, characterized in that it comprises a delay control means so as to supply to the audio output device. The distance measuring device according to claim 20 or claim 21 ,
A distance measuring device comprising test signal generating means for generating the test signal and supplying the test signal to the sound output device. A distance measuring device according to claim 20, claim 21 or claim 22 ,
The distance measuring means includes
Means for performing a fast Fourier transform on the measurement signal a predetermined number of times;
Means for obtaining an average of the power spectrum of the measurement signal subjected to fast Fourier transform;
Means for obtaining an autocorrelation of an audio signal from the object to be measured by performing inverse fast Fourier transform on the average of the power spectrum;
A distance measuring apparatus comprising: means for detecting a peak from the obtained autocorrelation and obtaining a relative distance with respect to the listening position for the speaker as a measurement target. A distance measurement correction apparatus having a plurality of audio channels for outputting audio signals,
A reference voice channel and another voice channel are selected and selected from the delay means for controlling the delay time of the voice signal for each of the plurality of voice channels and the plurality of voice channels according to the supplied distance parameter. A test signal having a predetermined shape is outputted through an audio channel, and a test signal having a different polarity is output between the reference audio channel and the other audio channel, and the other audio channel is changed every predetermined period. Switching means for switching to the audio channel,
Based on the measurement signal including the sound from the speaker of the reference sound channel and the sound from the speaker of the other sound channel picked up by the microphone arranged at the listening position, the relative of the speaker to be measured to the listening position A distance measuring means for determining a specific distance;
A distance measurement correction apparatus comprising: a parameter forming unit configured to form a distance parameter for the other audio channel based on a measurement result of the distance measuring unit and supply the distance parameter to the delay unit. The distance measurement correction device according to claim 24 ,
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the reference audio channel and the other audio channel within the predetermined period. and characterized in that it comprises one so as to vary several times a delay time of the audio signal, or delay variation means for both audio channels so as to vary the delay time of one channel each audio signal of the Distance measurement correction device to do. A distance measurement correction apparatus having a plurality of audio channels for outputting audio signals,
A reference voice channel and another voice channel are selected and selected from the delay means for controlling the delay time of the voice signal for each of the plurality of voice channels and the plurality of voice channels according to the supplied distance parameter. One of the two frequency test signals in an unharmonious relationship is output from the reference audio channel through the audio channel, and the other frequency test signal is output from the other audio channel. And switching means for switching the other audio channel to another audio channel every predetermined period;
Based on the measurement signal including the sound from the speaker of the reference sound channel and the sound from the speaker of the other sound channel picked up by the microphone arranged at the listening position, the relative of the speaker to be measured to the listening position A distance measuring means for determining a specific distance;
A distance measurement correction apparatus comprising: a parameter forming unit configured to form a distance parameter for the other audio channel based on a measurement result of the distance measuring unit and supply the distance parameter to the delay unit. The distance measurement correction device according to claim 26 ,
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the reference audio channel and the other audio channel within the predetermined period. and characterized in that it comprises one so as to vary several times a delay time of the audio signal, or delay variation means for both audio channels so as to vary the delay time of one channel each audio signal of the Distance measurement correction device to do. A distance measurement correction apparatus having a plurality of audio channels for outputting audio signals,
A reference voice channel and another voice channel are selected and selected from delay means for controlling the delay time of the voice signal for each of the plurality of voice channels and the plurality of voice channels according to the supplied distance parameter. A switching means for outputting a test signal which is a random noise signal through an audio channel, and switching the other audio channel to another audio channel every predetermined period;
By using the autocorrelation about the measurement signal and a voice from the voice and the other audio channel loudspeaker from the reference speech channel speaker picked up by a microphone arranged in the listening position, relative to listening position A distance measuring means for obtaining a relative distance of a speaker to be measured;
A distance measurement correction apparatus comprising: a parameter forming unit configured to form a distance parameter for the other audio channel based on a measurement result of the distance measuring unit and supply the distance parameter to the delay unit. The distance measurement correction apparatus according to claim 28 , wherein
In order to determine which of the speaker connected to the reference audio channel and the speaker connected to the other audio channel is closer to the listening position, the reference audio channel and the other audio channel within the predetermined period. and characterized in that it comprises one so as to vary several times a delay time of the audio signal, or delay variation means for both audio channels so as to vary the delay time of one channel each audio signal of the Distance measurement correction device to do. A distance measurement correction device according to claim 28 or claim 29 ,
The distance measuring means includes
Means for performing a fast Fourier transform on the measurement signal a predetermined number of times;
Means for obtaining an average of the power spectrum of the measurement signal subjected to fast Fourier transform;
Means for obtaining an autocorrelation of an audio signal from the object to be measured by performing inverse fast Fourier transform on the average of the power spectrum;
A distance measurement correction apparatus comprising: means for detecting a peak from the obtained autocorrelation and obtaining a relative distance with respect to the listening position for the speaker as a measurement target.

Images