JP4419993B2 - Listening position specifying system and listening position specifying method - Google Patents

Description

  The present invention relates to a listening position specifying system and a listening position specifying method in which a measurement sound emitted from a speaker unit is picked up by a microphone, and a listener's listening position is measured using an arrival time of the measuring sound. .

  2. Description of the Related Art Conventionally, audio devices that output multi-channel sound (multi-channel audio system), speaker array devices, and the like that output sound from a plurality of speaker units at a volume and delay time corresponding to a listener's listening position are known. . For example, in the case of a multi-channel audio system, a plurality of speaker units are arranged around the listener, and the volume level and delay time of the sound emitted from each speaker unit are adjusted, so that the listener is surrounded. Create a sound field. In the case of a speaker array device, a plurality of sound beams are formed by adjusting the timing and volume level of sound output from each speaker unit of a plurality of speaker units arranged in a matrix on the panel board, and A sound field is formed around the listener by a sound beam reflected on a wall or the like and directly emitted. In these devices, the volume level and output timing (delay time) of the audio signal of each channel is balanced so that the listener feels that the sound field is enveloped in the listening position without protruding only a specific channel. Well adjusted.

In the audio device and the speaker array device, in order to adjust the volume level and the output timing as described above, it is necessary to obtain the listening position in advance. Therefore, conventionally, a sound quality adjusting device that automatically detects the listening position of the listener has been proposed (see, for example, Patent Document 1).
JP-A-4-370000

  The sound quality adjusting device described in Patent Literature 1 includes two speaker units for L channel and R channel and a microphone. When measuring the listening position, the microphone is placed in the listening position in advance, and the measurement sound is emitted in order from the two speaker units, and the measurement sound is picked up by the microphone. The sound quality adjusting device measures the time until the measurement sound reaches the microphone from each of the two speaker units, and calculates the distance from the speaker unit to the microphone (listening position) based on the measurement time.

  In the conventional sound quality adjusting apparatus, the volume level of the measurement sound is always set to a high level so that the listening position can be reliably detected even under a certain level of noise. However, if the volume level of the measurement sound is set to a high level in this way, the measurement sound will have an unnecessarily high volume level when measured in an environment with a low background noise level or an environment with a high reverberation level. Therefore, there has been a problem that the listener is uncomfortable.

  Therefore, the present invention provides a listening position specifying system and a listening position specifying method capable of emitting sound for measurement whose volume level is adjusted in accordance with ambient environmental sounds without causing discomfort to the user. For the purpose.

  The present invention has the following configuration as means for solving the above problems.

(1) A microphone that is installed at a listening position for listening to sound emitted from a plurality of speaker units, and that collects measurement sound, and transmits a detection notification signal when the microphone picks up the measurement sound. A first communication unit, and a measurement terminal device comprising:
From a plurality of speaker units, a control unit that sequentially emits measurement sound from at least two speaker units among the plurality of speaker units, a second communication unit that receives the detection notification signal, and each speaker unit A sound output device comprising: a sound output device comprising: a calculation unit that calculates the listening position based on an arrival time from when the measurement sound is emitted until the second communication unit receives the detection notification signal In a specific system,
The measurement terminal device includes a signal level detection unit that detects a volume level of background noise collected by the microphone,
The first communication unit outputs a background level of background noise detected by the signal level detection unit,
The control unit sets the volume level of the measurement sound based on the volume level of the background noise.

  In this configuration, before emitting the measurement sound for specifying the listening position, the surrounding background noise is picked up by the microphone installed at the listening position and the volume level is measured. The volume level of the measurement sound is set based on the above, the measurement sound is sequentially emitted from the two speaker units, and the listening position is calculated based on the arrival time until the detection notification signal is received. Therefore, by setting the volume level to a low level that can be reliably picked up by the microphone without being distracted by background noise and does not cause discomfort to the listener, an appropriate volume level that matches the ambient sound around the listening position is set. The listening position can be specified by the level measurement sound.

(2) The audio output device includes a time measuring unit that measures the arrival time and the fixed time,
If the second communication unit does not receive the detection notification signal even if the time measuring unit measures a certain time, the control unit increases the volume level of the measurement sound by a certain amount and increases the two sound levels. The sound is emitted from the speaker unit.

  If the listening position is an unexpected position or an unexpected environment, the measurement sound will be output even though the measurement sound volume level is set based on the surrounding background noise volume level. An error occurs because the microphone cannot pick up the sound due to background noise. In this configuration, if the second communication unit does not receive the detection notification signal even after a predetermined time has elapsed, the measurement voice cannot be collected, so the measurement voice can be collected. The sound volume of the measurement sound is repeatedly increased by increasing the volume level of the measurement sound by a certain amount at regular intervals. Therefore, rather than setting the measurement sound to a high volume level in advance, the volume level of the measurement sound is gradually increased and set to a volume level that can be picked up by a microphone. You can set the volume level of the measurement audio.

  (3) The control unit may return the volume level of the measurement sound to an initial value when a first time elapses after increasing the volume level of the measurement sound.

  In this configuration, when the level changing procedure is not executed for the first time or more, the volume level of the measurement sound is returned to the initial value. Therefore, even if the listener moves after the listening position is specified and the listening position has changed or the background noise level has changed, the volume level of the measurement sound is increased after the first time has elapsed. Since it is returned to the initial value, the volume level of the measurement sound is reduced and the viewer is not uncomfortable.

  (4) The control unit is configured to set a detection threshold value of the measurement sound based on a volume level of the background noise.

  In the listening position specifying system, the volume level of the measurement sound is set based on the volume level of background noise. If the detection threshold of the measurement sound is a constant value, the measurement sound may not be detected. In this configuration, the control unit sets a detection threshold for detecting the measurement sound based on the background level of background noise. Therefore, by changing the detection threshold value for detecting the measurement sound according to the background level of the background noise, the measurement sound can be reliably detected regardless of the background level of the background noise.

(5) A storage unit for storing a reverberation level measured in advance in an indoor space where the audio output device is installed,
The control unit sets a sound emission time for each of the measurement sounds based on a reverberation level stored in the storage unit.

  Human auditory perception is integrated not only by the sound level but also by its duration, so that the overall volume level is recognized, so even if the sound volume level is the same, the higher the reverberation level in the room, the longer the reverberation time, I feel the volume level is high. In this configuration, the sound emission time of each measurement sound to be emitted sequentially from the two speaker units of the sound output device is set based on the reverberation level of the indoor space where the sound output device is installed. Therefore, the higher the reverberation level of the indoor space where the audio output device is installed, the shorter the sound output time of each measurement sound emitted from the two speaker units of the audio output device in order, the volume level felt by the listener Therefore, the listening position can be specified without causing discomfort to the listener.

  (6) The control unit sets a sound emission interval of each measurement sound to be emitted in order from two speaker units of the sound output device based on a reverberation level stored in the storage unit. .

  The sound output device emits the measurement sound from the two speaker units in order, but the reverberation time of the measurement sound becomes longer as the reverberation level of the indoor space where the sound output device is installed increases. If the interval at which sound is emitted is short, two measurement voices may be connected in some cases, and the measurement voice may be erroneously detected and the listening position may be incorrectly specified. In this configuration, the sound emission interval of each measurement sound emitted from the two speaker units is set based on the reverberation level of the indoor space where the sound output device is installed. Therefore, the higher the reverberation level of the indoor space where the audio output device is installed, the longer the sound emission interval time of each measurement sound emitted from the two speaker units is prevented from connecting the two measurement sounds. In addition, since the two measurement sounds can be reliably picked up, the listening position can be reliably specified.

(7) A procedure for collecting background noise with a microphone installed at a listening position for listening to sound emitted from a plurality of speaker units, and detecting a volume level of the background noise;
A procedure for setting the volume level of the measurement sound based on the volume level of the background noise,
A sound emission procedure for emitting sound for measuring the volume level from at least two speaker units of the plurality of speaker units;
Sound collection procedure for collecting each measurement sound with the microphone,
A procedure for calculating a listening position based on both arrival times from when the two speaker units emit each measurement sound until the microphone picks up the sound;
It is provided with.

  In this configuration, before emitting the measurement sound for calculating the listening position, the background noise is picked up by the microphone installed at the listening position and the volume level is measured, and based on the background level of the background noise. Set the volume level of the measurement audio. And both arrival time until sound for measurement emitted from at least two speaker units among a plurality of speaker units is picked up by the microphone, and sound for measurement emitted from each speaker unit is picked up by the microphone To calculate the listening position. Therefore, by setting the volume level to a low level that can be reliably picked up by the microphone without being distracted by background noise and does not cause discomfort to the listener, an appropriate volume level that matches the ambient sound around the listening position is set. The listening position can be specified by the level measurement sound.

  According to the present invention, before emitting the measurement sound for specifying the listening position, the background noise is picked up by the microphone installed at the listening position and the volume level is measured. Set the volume level of the measurement audio based on Then, the measurement sound emitted from the two speaker units is collected by the microphone, and the listening position is calculated based on the arrival time until the microphone collects the measurement sound emitted from the two speaker units. To do. Thereby, the sound for measurement can be reliably picked up by the microphone without being mixed with background noise, and the volume level of the sound for measurement can be set to a low volume level that does not cause discomfort to the listener. The listening position can be specified by the measurement sound having an appropriate volume level that matches the ambient sound around the listening position.

  FIG. 1 is a block diagram showing a schematic configuration of an audio system. The audio system 1 that is a listening position specifying system includes a speaker array device 3 and a remote control device 5 that is a measurement terminal device.

  The speaker array device 3 includes an input unit 11, a signal processing unit (decoder) 12, a beam forming unit 13, n D / A converters 15 (15-1 to 15-n), and n amplifiers 17 (17-1). To 17-n), and a speaker array 19 including speaker units SP1 to SPn. The speaker array device 3 includes an IR signal receiving unit 21, a system control unit 23, an operation unit 25, a display unit 27, and a storage unit 29. Further, the system control unit 23 includes a measurement audio processing unit 231 and a position detection processing unit 233. Further, the position detection processing unit 233 includes a timer unit 235, a time storage unit 237, and a calculation unit 239.

  The remote control device 5 includes a microphone MIC 31, an amplifier 33, an A / D converter 35, a signal level detection unit 37, a display unit 39, an operation unit 41, a control unit 43, and an IR code transmission unit 45.

  In the speaker array device 3, the input unit 11 is an interface circuit for a surround sound signal output from an external device (not shown), and the surround sound signal input from the external input terminal 111 passes through the signal processing unit 12. Decoding and post-processing are performed and output to the beam forming unit 13.

  The signal processing unit (decoder) 12 includes a measurement sound generation unit 121, generates a test sound signal that is measurement sound based on a control signal from the system control unit 23, and outputs the test sound signal to the beam forming unit 13. To do.

  The beam forming unit 13 generates a sound beam from the surround sound signal transmitted from the input unit 11 so that the listener can optimally listen to the surround sound at the listening position, and each D / A converter 15-1. Output to 15-n. The beam forming unit 13 forms an audio beam for each channel based on the delay control value (listening position information) output from the system control unit 23. When the beam forming unit 13 receives a control signal for emitting the measurement sounds 1 and 2 from the system control unit 23, the test sound signal output from the measurement sound generation unit 121 of the signal processing unit 12. Is output to the D / A converter 15-1 or the D / A converter 15-n. For example, a sine wave signal or an impulse signal may be used as the test audio signal.

  The D / A converters 15-1 to 15-n convert the digital audio signals output from the beam forming unit 13 into analog audio signals and output the analog audio signals to the amplifiers 17-1 to 17-n.

  The amplifiers 17-1 to 17-n amplify the analog audio signals output from the D / A converters 15-1 to 15-n and output the amplified signals to the speaker units SP1 to SPn of the speaker array 19.

  The speaker array 19 converts the surround sound signal amplified by the amplifiers 17-1 to 17-n into sound and emits the sound.

  When receiving the IR signal (infrared light signal) output from the remote control device 5, the IR signal receiving unit 21 converts the IR signal into an electrical signal and outputs it to the system control unit 23.

  The system control unit 23 switches the input of the speaker array device 3 and causes the beam forming unit 13 to output test sound data from the measurement sound generating unit 121.

  At this time, the measurement voice processing unit 231 determines the volume level of the measurement voices 1 and 2 based on the volume level (IR code) of the surrounding background noise measured by the remote control device 5. Set to.

  In addition, the position detection processing unit 233 informs that the remote controller 5 has collected the measurement sounds 1 and 2 after emitting the measurement sounds 1 and 2 from the speaker units SP1 and SPn of the speaker array 19. Therefore, the time t1 · t2 until the IR code transmitted for receiving is received is measured by the timer 235, and the time storage 237 stores this t1 · t2. Then, the calculation unit 239 calculates the position (listening position) of the remote control device 5 based on the arrival times t1 and t2, and outputs the listening position information to the beam forming unit 13.

  The operation unit 25 is for the user to perform an operation for controlling the operation of the speaker array device 3.

  The display unit 27 displays messages such as modes and errors set in the speaker array device 3.

  The storage unit 29 stores a program executed by the system control unit 23, a set value for executing the program, and the like.

  In the remote control device 5, the microphone MIC 31 is a directional microphone, picks up sound propagating from the surroundings, and outputs a sound signal to the amplifier 33.

  The amplifier 33 amplifies the audio signal output from the microphone MIC 31 and outputs the amplified audio signal to the A / D converter 35.

  The A / D converter 35 converts (samples) the analog audio signal amplified by the amplifier 33 into a digital audio signal and outputs the digital audio signal to the signal level detection unit 37.

  The signal level detection unit 37 outputs a volume level signal corresponding to the level (volume level) of the audio signal output from the A / D converter 35 to the control unit 43.

  The display unit 39 displays messages such as the mode being executed and errors.

  The operation unit 41 receives a listener's operation.

  The control unit 43 controls each unit of the remote control device 5.

  The IR code transmission unit 45 outputs an infrared light signal corresponding to the signal output from the control unit 43.

  Next, a method for specifying the listening position in the audio system 1 will be described. In order for only a specific listener to listen to the desired sound (audio content) from the speaker array device 3, the delay time to each audio signal based on the distance from the listener's listening position to each speaker unit SP1 to SPn Must be preset in the speaker array device 3.

  In order to set the delay time, the speaker array apparatus 3 executes a process (position detection process) for measuring the distance from the listening position to the speaker units SP (SP1, SPn) at both ends and detecting the listening position. Then, the speaker array device 3 calculates a delay time for the sound from the speaker units SP1 to SPn to reach the listening position at the same time, and sets it as a delay time to be added to the audio signal.

  FIG. 2 is a conceptual diagram for explaining position detection processing executed by the audio system. In the audio system 1, when the position detection process is executed, the remote controller 5 is arranged in advance at a position (listening position) where the listener listens to the sound emitted from the speaker array device 3. At this time, the microphone MIC31 of the remote control device 5 is arranged toward the speaker array 19 of the speaker array device 3.

  When the speaker array device 3 starts the position detection process, the speaker array device 3 sequentially outputs measurement sound from the speaker units SP1 and SPn at both ends. When the remote control device 5 picks up the measurement sound from the microphone MIC31, the remote control device 5 transmits a detection notification signal to that effect to the speaker array device 3.

  The speaker array device 3 has an arrival time t1 (first arrival time) from when the speaker unit SP1 emits the measurement sound until the remote control device 5 picks up the measurement sound and immediately receives the transmitted detection notification signal. ). Further, the arrival time t2 (second arrival time) from when the speaker unit SPn emits the measurement sound to when the detection notification signal is received is counted. The speaker array device 3 calculates the listening position using the arrival time t1 and the arrival time t2. Note that the time from when the remote control device 5 picks up the measurement sound to when the speaker array device 3 receives the detection notification signal is negligible, and is ignored. However, with respect to the system delay that takes time that cannot be ignored, the arrival times t1 and t2 are obtained by correcting for this time.

  As a method for calculating the listening position, a well-known method (triangulation method) described in Patent Document 1 or the like is used. Hereinafter, a calculation method for calculating the listening position will be described with reference to FIG.

  Here, for convenience of explanation, the arrangement direction of the speaker units SP is an X axis, and an axis orthogonal to the X axis and parallel to the horizontal direction is a Y axis. The X axis has a positive direction on the right side of the speaker array device 3, that is, the speaker unit SPn side. In the Y axis, the output direction of the audio signal from the speaker unit SP, that is, the user side is the positive direction. The intersection of the X axis and the Y axis, that is, the origin of the X axis and the Y axis is the center of the speaker units SP1 to SPn.

  When the arrival time t1 and the arrival time t2 are equal, it means that the distance between the remote control device 5 and the speaker unit SP1 is equal to the distance between the remote control device 5 and the speaker unit SPn. Therefore, remote control device 5 is located on the Y axis in FIG. 2, that is, in the center front of speaker array device 3 (position of remote control device 5 in the middle shown in FIG. 2). In this case, the calculation unit 239 calculates the remote control device 5 and the speaker array from the arrival time t1 or the arrival time t2, the sound speed c, and the distance (x1-x2) between the speaker unit SP1 and the speaker unit SPn according to the following equation (1). The distance y with the device 3 is calculated. Note that the X-axis coordinate of the speaker unit SP1 is x1, and the x-axis coordinate of the speaker unit SPn is x2.

y = [(c · t1) ² − {(x2−x1) / 2} ² ] ^1/2
= [(C · t2) ² − {(x 2 −x 1) / 2} ² ] ^1/2 Formula (1)
When the arrival time t1 ′ is longer than the arrival time t2 ′, it means that the distance between the remote control device 5 and the speaker unit SP1 is longer than the distance between the remote control device 5 and the speaker unit SPn. Therefore, when the remote controller 5 is closer to the speaker unit SPn than the center of the speaker array apparatus 3, that is, when the remote controller 5 is viewed from the front in FIG. Located in. In this case, the calculation unit 239 calculates the coordinate x ′ on the X axis of the remote control device 5 and the distance y ′ between the remote control device 5 and the speaker array device 3 by the following equations (2) and (3).

x ′ = [(c · t1 ′) ² − (c · t2 ′) ² + (x2) ² − (x1) ² ] / [2 (x2−x1)] (2)
y ′ = [(c · t2 ′) ² − (x2−x ′) ² ] ^1/2
= [(C · t1 ′) ² − (x′−x1) ² ] ^1/2 Formula (3)
When the arrival time t1 ″ is shorter than the arrival time t2 ″, it means that the distance between the remote control device 5 and the speaker unit SP1 is shorter than the distance between the remote control device 5 and the speaker unit SPn. Therefore, when the remote controller 5 is closer to the speaker unit SP1 than the center of the speaker array apparatus 3, that is, when viewed from the front in FIG. 2, the remote controller 5 is on the left side of the Y axis (position of the remote controller 5 at the left end shown in FIG. 2). Located in. In this case, the calculation unit 239 calculates the coordinate x ″ on the X axis of the remote control device 5 and the distance y ″ between the remote control device 5 and the speaker array device 3 by the following equations (4) and (5).

x ″ = [(c · t1 ″) ² − (c · t2 ″) ² + (x2) ² − (x1) ² ] / [2 (x2−x1)] Equation (4)
y ″ = [(c · t2 ″) ² − (x2−x ″) ² ] ^1/2
= [(C · t1 ″) ² − (x ″ −x1) ² ] ^1/2 ... Formula (5)
Next, in the audio system 1, when the listening position is specified as described above, the volume level of the background noise is first measured before the listening position detection process, and the volume level of the background noise is measured. Then, the volume level of the measurement sound is set, and the position detection process for emitting the measurement sound is performed. That is, when the background noise around the listening position where the remote control device 5 is installed is small, the volume of the measurement sound emitted from the speaker units SP1 and SPn of the speaker array device 3 is also reduced and is mixed with the background noise. The sound volume for measurement is set to a volume level that can be picked up by the microphone MIC31. Further, when the background noise around the listening position where the remote controller 5 is installed is large, the volume of the measurement sound emitted from the speaker units SP1 and SPn of the speaker array device 3 is also increased, and the background noise is lost. The sound volume for measurement is set to a volume level that can be picked up by the microphone MIC31. By doing so, the volume level of the measurement sound emitted from the speaker array device 3 can be picked up (detected) by the microphone MIC31 without being influenced by the surrounding background noise, and uncomfortable for the listener. Can be set to an appropriate volume level without giving

  Further, in the audio system 1, when the listening position is specified as described above, the surrounding background noise volume level is measured before the listening position detection process, and based on the background noise volume level. After determining (setting) the detection threshold of the measurement sound, a position detection process for emitting the measurement sound is performed. That is, when the background noise around the listening position where the remote control device 5 is installed is small, the detection threshold of the measurement sound emitted from the speaker units SP1 and SPn of the speaker array device 3 is also reduced to the background noise level. Accordingly, when the volume of the measurement sound is set to be small, the measurement sound is set to a value that can be reliably detected. When the background noise around the listening position where the remote control device 5 is installed is large, the detection threshold value of the measurement sound emitted from the speaker units SP1 and SPn of the speaker array device 3 is also increased so that the background noise level is reached. Accordingly, when the volume of the measurement sound is set large, the measurement sound is set to a value that can be reliably detected. In this way, the measurement sound can be reliably detected regardless of the background level of background noise.

  When the remote controller 5 detects that the listener has set the listening position specifying mode by operating the operation unit 41, the microphone MIC31 collects ambient background noise. In the remote control device 5, the signal level detection unit 37 detects the background level of the background noise and outputs a signal (IR code) corresponding to the background level of the background noise from the IR code sending unit 45.

  FIG. 3 is a table showing the relationship between the background noise level and the IR code. FIG. 3 shows an example in which the background level of background noise is classified into four stages for the sake of simplicity. The remote control device 5 sends out the IR code A when the background level of the background noise is low, and the IR codes B, C, and S in order according to the volume level as the background level of the background noise during measurement increases. D is sent out.

  The speaker array device 3 adjusts the volume level of the measurement sound by the amplifiers 17-1 to 17-n, and the measurement sound is output from the speaker array 19 at a volume level corresponding to the IR code received by the IR signal receiving unit 21. Sounds out. That is, when receiving the IR code A, the speaker array device 3 emits the measurement sound with the lowest volume level. Further, the speaker array device 3 increases the volume level and emits the measurement sound as the received IR codes become B, C, and D in order.

  Next, in the audio system 1, as described above, the volume level of the measurement sound is set according to the volume level of background noise at the listening position where the remote control device 5 is installed, but depending on the listening position with respect to the speaker array device 3. May not be able to set the volume level of the measurement sound to an appropriate value. That is, the volume level of the measurement sound is set in advance so as to be appropriate at an assumed listening position such as near the center of the room. However, if the listening position is an unexpected position such as the end of the room or under an unexpected environment, the remote control device 5 outputs the measurement sound whose volume level is set based on the volume level of the surrounding background noise. The microphone MIC31 cannot pick up (detect) the sound, resulting in an error. Therefore, in the audio system 1, within the first preset time, the volume level of the measurement sound with respect to the background noise level initially assigned is increased by a certain amount until the microphone MIC 31 can pick up the sound. It is set to perform re-measurement.

  Thereby, the measurement success probability at the time of re-measurement can be improved, and the operation under various environments can be guaranteed. Further, the volume level offset is cleared to zero (returned to the initial value) if the first time measurement is not performed. Therefore, when the measurement environment returns to the normal level, the volume level offset is higher than necessary. Measurement can be prevented from being performed.

  Specifically, the audio system 1 performs processing as follows. FIG. 4 is a diagram illustrating the relationship between the volume level of background noise and the volume level of measurement sound. Here, in FIG. 4, the minimum value of the volume level is set to 1 for both the background noise and the measurement sound, and the numerical value increases as the volume level increases.

  In the audio system 1, for example, when the background noise is at the volume level 1, the system control unit 23 of the speaker array device 3 sets the volume level of the measurement sound to 1 (see FIG. 4A), and the speaker unit. The sound for measurement of volume level 1 is emitted from SP1 and SPn. However, if the remote controller 5 cannot pick up the measurement sound with the microphone MIC31 and does not respond after a certain period of time, the system control unit 23 increases the volume level of the measurement sound by one step. The level is set to 2 (see FIG. 4B), and the sound for measurement at volume level 2 is emitted from the speaker units SP1 and SPn.

  If the remote controller 5 cannot pick up the sound for measurement at the sound volume level 2 with the microphone MIC 31 and does not respond after a predetermined time has passed, the system controller 23 further increases the sound volume level for the sound for measurement to 1. The volume level is increased to 3 (see FIG. 4C) and the measurement sound is emitted from the speaker units SP1 and SPn. Further, even if the volume level of the measurement sound is set to 3, the system control unit 23 is unable to pick up sound with the microphone MIC31 of the remote control device 5, and if there is no response after a certain period of time, the measurement is performed. The volume level of the audio is further increased by one level and the volume level is set to 4 (see FIG. 4D), and the measurement audio is emitted from the speaker units SP1 and SPn.

  In this manner, the system control unit 23 increases the volume level of the measurement sound by one step (a fixed amount) until the measurement sound can be detected. As a result, the sound level for measurement is not set to a high volume level in advance, but the volume level of the sound for measurement is gradually increased and set to a volume level that can be picked up by a microphone. The volume level of the measurement sound can be set without any problem.

  In addition, the speaker array device 3 returns the volume level of the measurement sound to 1 when the first time (a time longer than the predetermined time) has elapsed since the remeasurement of the measurement sound was repeated. As a result, even if the listener moves and the listening position changes or the background level of background noise changes, the volume level of the measurement sound returns to the original value (initial value) after the first time has elapsed. Therefore, the volume level of the measurement sound is reduced and the viewer is not uncomfortable.

  It should be noted that a certain amount for increasing the volume level of the measurement sound may be set in advance through experiments or the like.

  Next, if the reverberation level of the place where the audio system 1 is installed is different, even if the volume level of the measurement sound is the same, the sound volume may be heard differently, which may cause discomfort to the listener. FIG. 5 is a diagram illustrating the relationship between the reverberation level and the elapsed time, and the relationship between the reverberation time and the sounding time. For example, as shown in FIG. 5A, when the measurement sound is emitted in an indoor space where the reverberation level is high, the reverberation time is long, so that the listener feels that the volume level is high. This is due to the following reason. In other words, human beings recognize not only the sound level but also the overall sound volume level by integrating its duration, so even if the sound volume level is the same, the higher the reverberation level in the room, the higher the sound volume level. Because it feels. Therefore, in the audio system 1, as shown in FIG. 5B, the longer the reverberation time in the indoor space in which the speaker array device 3 is installed (the higher the reverberation level), the two speakers in the speaker array device 3 are in order. Reduce the sound emission time of each measurement sound to be emitted. Thereby, a listening position can be specified without giving a listener a discomfort.

  Also, the higher the reverberation level in the indoor space, the longer the sound reverberates. Therefore, in the audio system 1, as shown in FIG. 5C, the longer the reverberation time in the indoor space (the higher the reverberation level), the sound emission interval between the measurement sound 1 and the measurement sound 2 (sound emission start). Increase the interval. For example, when the reverberation level is small, the sound emission interval between the measurement sound 1 and the measurement sound 2 is set to tc, and the sound emission interval between the measurement sound 1 and the measurement sound 2 is increased as the reverberation level increases. Is set to tb or ta. Thereby, since the measurement sound 2 can be emitted before the reverberation of the measurement sound 1 disappears and the two sounds are prevented from overlapping, the listening position can be reliably identified based on the measurement sounds 1 and 2. .

  Since the reverberation level in the indoor space does not fluctuate, the reverberation level in the indoor space is measured in advance and stored in the storage unit 29, and the reverberation level is read during the listening position specifying process, and the sound emission according to the reverberation level is read out. It is better to emit the measurement sound over time. As a method for measuring the reverberation level in the room, for example, an automatic reverberation time measurement method described in Japanese Patent Laid-Open No. 8-247837 may be used.

  Next, an operation when performing the listening position specifying process in the audio system 1 will be described based on a flowchart. FIG. 6 is a flowchart for explaining the operation of the remote control device and the speaker array device constituting the audio system.

  Here, immediately after installation, the audio system 1 measures the reverberation level in the room and stores it in the storage unit 29. When performing the listening position specifying process, the audio system 1 measures based on the reverberation level read from the storage unit 29. Set sound release time and interval.

  As illustrated in FIG. 6, when the control unit 43 of the remote control device 5 detects that the user has set to execute the listening position specifying process by operating the operation unit 41 (s1), the start of the listening position specifying process is started. Is transmitted from the IR code transmitter 45 (s2).

  When the system control unit 23 of the speaker array device 3 detects that the IR signal is received by the IR signal receiving unit 21 (s51), the system control unit 23 receives the start of the listening position specifying process and performs initial setting (s52).

  Following step s2, the control unit 43 of the remote control device 5 picks up ambient background noise with the microphone MIC31 and detects the volume level with the signal level detection unit 37 (s3). And the control part 43 sends out IR code according to the volume level of the background noise detected by the signal level detection part 37 from the IR code sending part 45 (s4). Moreover, the control part 43 starts the detection process of the audio | voice 1 for a measurement (s5).

  Based on the IR code corresponding to the background level of background noise in the IR signal receiving unit 21, the system control unit 23 of the speaker array device 3 uses the measurement sound processing unit 231 to measure measurement sound corresponding to the background level of background noise. The sound volume level and the measurement sound detection threshold are determined, the amplification factor of the amplifier 17-1 is changed, and the measurement sound 1 is emitted from the speaker unit SP1 (s53). At this time, the sound emission time of the measurement sound 1 is set based on the reverberation level of the indoor space in which the audio system 1 is installed. Further, the system control unit 23 starts measuring time by the time measuring unit 235 simultaneously with the start of sound emission of the measurement sound 1 (s54).

  If the microphone MIC31 can pick up and detect the measurement voice 1 without being mixed with background noise (s6), the control unit 43 of the remote control device 5 immediately detects that the measurement voice 1 has been detected (IR code ( A detection notification signal of the measurement sound 1) is sent from the IR code sending unit 45 (s7).

  When the system control unit 23 of the speaker array device 3 receives the IR code (detection notification signal of the measurement sound 1) by the IR signal reception unit 21 (s55), the system control unit 23 confirms the time measuring unit 235 and releases the measurement sound 1. The arrival time t1 from when the sound is heard until the IR code is received is stored in the time storage unit 237 (s56).

  On the other hand, when the measurement sound 1 cannot be detected due to background noise (s6), the control unit 43 of the remote control device 5 cannot respond to the speaker array device 3, and continues to detect the measurement sound 1. .

  The system control unit 23 cannot receive the IR code (detection notification signal of the measurement sound 1) from the remote control device 5 (s55), and when a certain time has elapsed since the time measurement unit 235 started time measurement ( s57), it is determined that the remote control device 5 has not detected the measurement sound 1, and the time measuring unit 235 is reset, the volume level of the measurement sound 1 is increased by one level, and the measurement sound 1 is emitted again. (S58). At this time, the system control unit 23 starts measuring time with the time measuring unit 235 simultaneously with the start of sound emission of the measurement sound 1 (s54).

  The control unit 43 of the remote control device 5 continues the process of step s6 until the measurement sound 1 can be detected. When the measurement sound 1 is detected, the control unit 43 immediately detects that the measurement sound 1 has been detected. A detection notification signal of voice 1 is sent from the IR code sending unit 45 (s7). Moreover, the control part 43 starts the detection process of the audio | voice 2 for a measurement (s10).

  The system control unit 23 repeats the processing of steps s54 → s55 → s57 → s58 → s54 until it receives the IR code (detection notification signal of the measurement sound 1) from the remote control device 5 and receives the IR code (s55). ) The time measuring unit 235 is checked, and the arrival time t1 from when the measurement sound 1 is emitted until the IR code is received is stored in the time storage unit 237 (s56).

  Subsequently, the system control unit 23 of the speaker array device 3 confirms the time measuring unit 235, and after the sound for measurement 1 is emitted, the time corresponding to the sound emission interval set in accordance with the reverberation level in the indoor space. If not, the system waits until the time corresponding to the sound emission interval elapses. When the time corresponding to the sound emission interval elapses (s60), the system control unit 23 causes the measurement sound 2 to be emitted from the speaker unit SP1 at the volume level of the measurement sound determined in step s53 (s61). At this time, the system control unit 23 starts measuring time in the time measuring unit 235 simultaneously with the start of sound emission of the measurement sound 2 (s62).

  When the microphone MIC31 can pick up and detect the measurement sound 2 without being confused by background noise (s11), the control unit 43 of the remote control device 5 immediately detects that the measurement sound 2 has been detected by an IR code ( The detection notification signal of the measurement sound 2) is sent from the IR code sending unit 45 (s12). Then, the control unit 43 ends the listening position specifying process.

  When the IR signal receiving unit 21 receives the IR code (detection notification signal of the measurement sound 2) (s63), the system control unit 23 of the speaker array device 3 stops the time measuring unit 235 and releases the measurement sound 2. The arrival time t2 from when the sound is heard until the IR code is received is stored in the time storage unit 237 (s64). In addition, the timer unit 235 is reset to stop timing.

  On the other hand, when the measurement sound 2 cannot be detected due to background noise (s11), the control unit 43 of the remote control device 5 cannot respond to the speaker array device 3, and continues to detect the measurement sound 2. .

  The system control unit 23 cannot receive the IR code (detection notification signal of the measurement sound 2) from the remote control device 5 (s63), and when a certain time has elapsed since the time measurement unit 235 started time measurement ( s65), it is determined that the remote control device 5 has not detected the measurement sound 2, and the timer 235 is reset, the measurement signal level of the measurement sound 2 is increased by one step, and the measurement sound 2 is released again. Sound (s66). At this time, the system control unit 23 starts measuring time with the time measuring unit 235 simultaneously with the start of sound emission of the measurement sound 2 (s62).

  The control unit 43 of the remote control device 5 continues the process of step s11 until the measurement sound 2 can be detected. When the measurement sound 2 is detected, the control unit 43 immediately detects that the measurement sound 2 has been detected. (Sound 2 detection notification signal) is sent from the IR code sending unit 45 (s12). Then, the control unit 43 ends the listening position specifying process.

  Further, the system control unit 23 repeats the process of steps s62 → s63 → s65 → s66 → s62 until it receives the IR code from the remote control device 5 until it receives the IR code (detection notification signal of the measurement sound 1). (S62) The time measuring unit 235 is stopped, and the arrival time t2 from when the measurement sound 2 is emitted until the IR code is received is stored in the time storage unit 237 (s63). In addition, the timer unit 235 is reset to stop timing.

  Subsequently, the system control unit 23 of the speaker array device 3 reads the arrival times t1 and t2 from the time storage unit 237, and based on these arrival times, the equations (1) to (5) as described above are obtained. By performing the calculation, the distance from the speaker units SP1 and SPn to the listening position is calculated (s67).

  Then, the system control unit 23 sets a delay control value in the beam forming unit 13 so that the sound beam is directed to the listening position (s68), and ends the listening position specifying process.

  In the above description, in step s61, the measurement sound 2 is emitted from the speaker unit SP1 at the volume level of the measurement sound based on the background noise determined in step s53. However, in step s55, the IR is measured. When the code is received, the volume level of the measurement sound 2 may be set based on the volume level of the measurement sound 1 immediately before that code. For example, the volume level of the measurement sound 2 may be set to the same volume level as the final volume level of the measurement sound 1.

  In the above description, the background noise and the measurement sounds 1 and 2 are collected by the microphone MIC31 provided in the remote control device 5. However, the present invention is not limited to this, and the wired microphone cable installed at the listening position is not limited thereto. May be connected to the speaker array device 3, and the speaker array device 3 may perform processing of the background noise collected by the microphone and the measurement sounds 1 and 2. The microphone may be wireless (wireless type) or wired (wired type), and the speaker array device 3 may be configured according to the form of the microphone.

  In the above description, the measurement sound is emitted from the speaker units SP1 and SPn. However, the present invention is not limited to this, and the measurement sound may be emitted from another speaker unit SP. . Although the measurement sound is emitted from the speaker units SP1 and SPn, the measurement sound can also be emitted from another speaker unit.

  Moreover, although the speaker array apparatus 3 is configured to integrally include the speaker array 19, the present invention is not limited to this. For example, the speaker array 19 and a functional unit that performs signal processing for adjusting a delay time and an output level on the audio signal may be used instead of the configuration provided separately.

  Further, the present invention is not applied only to the audio system 1 including the speaker array device 3 and the remote control device 5, but can be applied to, for example, a multi-channel audio system including a plurality of speaker units.

It is a block diagram which shows schematic structure of an audio system. It is a conceptual diagram for demonstrating the position detection process which an audio system performs. It is a table | surface which shows the relationship between the level of background noise, and IR code. It is a figure which shows the relationship between the volume level of background noise, and the volume level of the sound for a measurement. It is a figure which shows the relationship between reverberation level and elapsed time, and the relationship between reverberation time and sound generation time. It is a flowchart for demonstrating operation | movement of the remote control apparatus and speaker array apparatus which comprise an audio system.

Explanation of symbols

1-Audio system 3-Speaker array device 5-Remote control device 11-Input unit 13-Beam forming unit 15-D / A converter 17, 33-Amplifier 19-Speaker array 21-IR signal receiving unit 23-System control unit 25- Operation unit 27-Display unit 29-Storage unit 35-A / D converter 37-Signal level detection unit 39-Display unit 41-Operation unit 43-Control unit 45-IR code sending unit 111-External input terminal 231-Audio for measurement Processing unit 233-Position detection processing unit 235-Timekeeping unit 237-Time storage unit 239-Calculation unit MIC31-Microphone SP, SP1 to SPn-Speaker unit

Claims (7)

A microphone that is installed at a listening position for listening to sounds emitted from a plurality of speaker units, and that receives a measurement sound, and a detection notification signal that is transmitted when the microphone picks up the measurement sound. A measurement terminal device comprising a communication unit;
From a plurality of speaker units, a control unit that sequentially emits measurement sound from at least two speaker units among the plurality of speaker units, a second communication unit that receives the detection notification signal, and each speaker unit A sound output device comprising: a sound output device comprising: a calculation unit that calculates the listening position based on an arrival time from when the measurement sound is emitted until the second communication unit receives the detection notification signal In a specific system,
The measurement terminal device includes a signal level detection unit that detects a volume level of background noise collected by the microphone,
The first communication unit outputs a background level of background noise detected by the signal level detection unit,
The control unit is a listening position specifying system that sets a volume level of the measurement sound based on a volume level of the background noise. The audio output device includes a time measuring unit that measures the arrival time and a certain time,
If the second communication unit does not receive the detection notification signal even if the time measuring unit measures a certain time, the control unit increases the volume level of the measurement sound by a certain amount and increases the two sound levels. The listening position specifying system according to claim 1, wherein sound is emitted from the speaker unit.   The listening position specifying system according to claim 2, wherein the control unit returns the volume level of the measurement sound to an initial value when a first time elapses after increasing the volume level of the measurement sound.   The listening position specifying system according to any one of claims 1 to 3, wherein the control unit sets a detection threshold value of the measurement sound based on a volume level of the background noise. A storage unit for storing a reverberation level measured in advance in an indoor space in which the audio output device is installed;
The listening position specifying system according to any one of claims 1 to 4, wherein the control unit sets a sound emission time of each of the measurement sounds based on a reverberation level stored in the storage unit.   The listening position according to claim 5, wherein the control unit sets a sound emission interval of each measurement sound to be emitted sequentially from two speaker units of the sound output device based on a reverberation level stored in the storage unit. Specific system. A procedure for picking up background noise with a microphone installed at a listening position for listening to sound emitted from a plurality of speaker units, and detecting a level of the background noise.
A procedure for setting the volume level of the measurement sound based on the volume level of the background noise,
A sound emission procedure for emitting sound for measuring the volume level from at least two speaker units of the plurality of speaker units;
Sound collection procedure for collecting each measurement sound with the microphone,
A procedure for calculating a listening position based on both arrival times from when the two speaker units emit each measurement sound until the microphone picks up the sound;
A listening position specifying method comprising:

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