Acoustic controller

Abstract

To provide an acoustic controller which makes target sound heard in real time through an output device less audible.SOLUTION: An acoustic controller includes: a sound acquisition part; an acoustic processing part; and a reproduction control part. The sound acquisition part acquires interference sound data and / or anti-sound data including information on interference sound which acts as noise to interfere with listening of target sound, which a listener listens. The acoustic processing part performs acoustic processing for interfering with listening of target sound on acquired interference sound data and / or anti-sound data. The reproduction control part reproduces interference sound data and / or anti-sound data on which acoustic processing is performed from an output device of a system.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD An embodiment of the present invention relates to an acoustic control device. [Background technology]

[0002] One known technique for making specific sounds harder to hear is to play a masking sound separate from the specific sound in the space surrounding the sound source that is playing the specific sound. By playing such a masking sound, it becomes difficult for third parties to hear the specific sound in question. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5732937 Summary of the Invention [Problem to be solved by the invention]

[0004] The playback of masking sounds is primarily used to prevent third parties from hearing sounds. Recently, however, there have been frequent cases of sounds from mobile phones being used to instruct users to commit fraudulent acts or to instruct users to perform erroneous actions, such as transferring money to criminal accounts or purchasing prepaid cards as part of a fraudulent scheme. It is desirable that sounds that lead to such fraudulent acts be inaudible even to listeners listening to the sounds in real time from a mobile phone. Thus, if the audibility of sounds heard in real time through some kind of output device could be appropriately controlled, it would be possible to use sounds more safely and effectively.

[0005] The embodiment provides a sound control device that can make a target sound heard in real time through an output device less audible. [Means for solving the problem]

[0006] An acoustic control device according to one embodiment includes a sound acquisition unit, an acoustic processing unit, and a playback control unit. The sound acquisition unit acquires interfering sound and / or opposing sound data including information about interfering sounds that act as noise to interfere with a listener's ability to hear a target sound. The acoustic processing unit performs acoustic processing on the acquired interfering sound data and / or opposing sound data to interfere with a listener's ability to hear the target sound. The playback control unit reproduces the acoustically processed interfering sound data and / or opposing sound data from an output device. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a functional block diagram showing the configuration of an acoustic control device according to each embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of a hardware configuration of the acoustic control apparatus according to the first embodiment. [Figure 3] FIG. 3 is a flowchart showing the operation of the acoustic control device of the first embodiment. [Figure 4] FIG. 4 is a diagram illustrating an example of a hardware configuration of the acoustic control apparatus according to the second embodiment. [Figure 5] FIG. 5 is a flowchart showing the operation of the acoustic control device of the second embodiment. [Figure 6] FIG. 6 is a diagram showing the state of a listener in the second embodiment. [Figure 7] FIG. 7 is a flowchart showing the operation of the acoustic control device of the third embodiment. [Figure 8] FIG. 8 is a diagram showing the state of a listener in the third embodiment. [Figure 9] FIG. 9 is a flowchart showing the operation of the acoustic control device of the fourth embodiment. [Figure 10] FIG. 10 is a diagram showing the state of a listener in the fourth embodiment. [Figure 11] FIG. 11 is a flowchart showing the operation of the acoustic control device of the fifth embodiment. [Figure 12] FIG. 12 is a diagram showing the state of a listener in the fifth embodiment. [Figure 13] FIG. 13 is a diagram showing a modified example of the fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment will be described with reference to the drawings. (First embodiment) First, a first embodiment will be described. Fig. 1 is a functional block diagram showing the configuration of an acoustic control device according to each embodiment. As shown in Fig. 1, the acoustic control device 1 has a sound acquisition unit 10, an acoustic processing unit 20, and a playback control unit 30. The acoustic control device 1 can be mounted on or installed in the periphery of various devices that emit sound, such as various terminal devices such as mobile phones, smartphones, and tablet devices, as well as sound guidance systems that provide various sound guidance to listeners.

[0009] The sound acquisition unit 10 acquires sound data to be processed. The sound data includes interfering sound data. The target sound data to be interfering with is data containing information about the sound that the listener is trying to hear in real time. The sound in this case is often human voice, but is not necessarily limited to human voice. The interfering sound data is data containing information about interfering sounds that act as noise to interfere with the audibility of the target sound. Interfering sounds can include, for example, masking sounds such as the babbling of a stream, or meaningless sounds such as human noise and the sound of numbers being read aloud. Here, it is desirable that the type and frequency band of the interfering sound data have a band common to the target sound to be interfering with and are not extremely unpleasant to humans. The frequency band may be adjusted by a frequency band adjustment process described later. The interfering sound data may be stored in advance in a storage device (not shown) of the acoustic control device 1, or may be generated in real time.

[0010] The sound processing unit 20 performs sound processing on the sound data acquired by the sound acquisition unit 10. The sound processing includes, for example, volume adjustment processing and frequency band adjustment processing. Volume adjustment processing is processing to increase or decrease the volume of the input sound data. Frequency band adjustment processing is processing to emphasize or weaken a specific frequency band in the input sound data. In particular, the sound processing unit 20 performs volume adjustment processing and frequency band adjustment processing, either alone or in combination, on the interfering sound data to draw the listener's attention to the interfering sound. Note that the processing to draw the listener's attention to the interfering sound is not limited to volume adjustment processing and frequency band adjustment processing.

[0011] The reproduction control unit 30 reproduces the sound data processed by the sound processing unit 20 through a speaker serving as a sound reproduction unit. Here, the reproduction control unit 30 can reproduce at least the interference sound data through the speaker.

[0012] FIG. 2 is a diagram showing an example of the hardware configuration of the sound control device 1 of the first embodiment. The sound control device 1 has, as its hardware configuration, for example, a processor 101, a memory 102, a storage 103, an acoustic processing circuit 104, and a speaker 105. Here, the sound control device 1 may have hardware elements other than those shown in FIG. 2. For example, the sound control device 1 may have a display device for displaying various images. The sound control device 1 may also have a communication circuit for performing communication. Furthermore, the sound control device 1 may have an operation interface such as buttons or a touch panel operated by a listener. Furthermore, the sound control device 1 may have a microphone for picking up sound from an external sound source and a camera for acquiring external images.

[0013] The processor 101 controls the overall operation of the acoustic control device 1. The processor 101 operates as the sound acquisition unit 10 and the acoustic processing unit 20 by executing, for example, an acoustic control program 1031 stored in the storage 103. The processor 101 is, for example, a CPU. The processor 101 may be an MPU, a GPU, an ASIC, an FPGA, or the like. The processor 101 may be a single CPU or the like, or multiple CPUs or the like. Furthermore, the operation of the processor 101 is not limited to this description.

[0014] The memory 102 includes a ROM and a RAM. The ROM is a non-volatile memory. The ROM stores a startup program for the acoustic control device 1 and the like. The RAM is a volatile memory. The RAM is used as a working memory when the processor 101 performs processing, for example.

[0015] The storage 103 is, for example, a storage such as a flash memory, a hard disk drive, or a solid state drive. The storage 103 stores various programs executed by the processor 101, such as an acoustic control program 1031. The storage 103 may also store interfering sound data.

[0016] The acoustic processing circuit 104 is a circuit configured to operate together with the processor 101 as the acoustic processing unit 20 and the playback control unit 30, to perform acoustic processing on input sound data, or to select sound data that has already been acoustically processed, and to play this sound data through the speaker 105.

[0017] The speaker 105 is one or more speakers for reproducing the interfering sound data.

[0018] Next, the operation of the acoustic control device 1 of the first embodiment will be described. Fig. 3 is a flowchart showing the operation of the acoustic control device 1 of the first embodiment. The operation of Fig. 3 is controlled by the processor 101.

[0019] In step S1, the situation in the space including this system is recognized, and information for determining whether or not to output interfering sound is collected. The mechanism for implementing step S1 may be executed by processor 101 included in the system of this control device, or may be included in a mechanism outside the system.

[0020] In step S2, processor 101 determines whether or not it is necessary to output an interfering sound. If it is determined in step S2 that it is not necessary to output an interfering sound, the process proceeds to step S7. If it is determined in step S2 that it is necessary to output an interfering sound, the process proceeds to step S3.

[0021] In step S3, the processor 101 outputs the interfering sound data to the acoustic processing circuit 104, performs the processes of steps S4 and S5 on the interfering sound data, and instructs the acoustic processing circuit 104 to play the interfering sound data. In response to this, the acoustic processing circuit 104 plays the target sound data through the speaker 105. This process is performed in step S6. Also, if the interfering sound has already been generated and saved in the storage 103 or the like, the processes of steps S3, S4, and S5 are omitted.

[0022] In step S4, the processor 101 outputs the interfering sound data to the acoustic processing circuit 104. Then, the processor 101 causes the acoustic processing circuit 104 to perform a volume adjustment process on the interfering sound data. The acoustic processing circuit 104 performs a process of randomly increasing or decreasing the volume as the volume adjustment process on the interfering sound data. Humans tend to recognize sounds whose volume changes randomly as foreign sounds. Therefore, by changing the volume of the interfering sound, it is possible to draw the listener's attention to the interfering sound. As a result, the listener becomes less aware of the target sound. In other words, it becomes more difficult for the listener to hear the target sound.

[0023] In step S5, the processor 101 causes the acoustic processing circuit 104 to perform frequency band adjustment processing on the interfering sound data. The acoustic processing circuit 104 performs, for example, processing to emphasize a frequency band similar to that of the target sound data as the frequency band adjustment processing on the interfering sound data. For example, if the target sound is a human voice, the frequency band of the interfering sound is emphasized so that it becomes similar to the human voice of the target sound. This can draw the listener's attention to the interfering sound. As a result, the listener becomes less aware of the target sound. In other words, the listener finds it more difficult to hear the target sound.

[0024] In step S6, the processor 101 instructs the sound processing circuit 104 to reproduce the interfering sound data. In response to this, the sound processing circuit 104 reproduces the interfering sound data from the speaker 105.

[0025] In step S7, processor 101 determines whether or not to end the operation of Fig. 3. For example, if an instruction to end the operation is given by a listener operating a button or the like, it is determined that the operation of Fig. 3 is to be ended. If it is not determined in step S7 that the operation of Fig. 3 is to be ended, processor 101 returns the process to step S2. If it is determined in step S7 that the operation of Fig. 3 is to be ended, processor 101 ends the operation of Fig. 3.

[0026] As described above, in the first embodiment, acoustic processing is performed on an interfering sound that is different from the target sound that the listener is trying to hear, to draw the listener's attention to the interfering sound, i.e., to make the target sound harder to hear.The target sound and the interfering sound are then reproduced so that they can be heard by the listener simultaneously.By reproducing the interfering sound after such acoustic processing, the listener's ability to hear the target sound that the listener is trying to hear can be more effectively hindered than by simply reproducing the interfering sound.

[0027] Here, in the example of Fig. 3, both the volume adjustment process and the frequency band adjustment process are performed as the acoustic process. However, in Fig. 3, only one of the volume adjustment process and the frequency band adjustment process may be performed as the acoustic process.

[0028] (Second embodiment) Next, a second embodiment will be described. Here, a description of the same parts of the second embodiment as those of the first embodiment will be omitted. That is, the basic functional blocks shown in FIG. 1 can be applied to the second embodiment as well. However, in the second embodiment, the acoustic processing unit 20 can perform sound image localization processing in addition to volume adjustment processing and frequency band adjustment processing. The sound image localization processing is a process for localizing a sound image in the space around the listener using two-channel speakers. The sound image localization processing can create the illusion for the listener that a sound is coming from a direction different from the direction of the actual speakers. Specifically, the sound image localization processing is a process for generating two-channel sound data by convolving sound data with a filter calculated based on a head-related transfer function between a virtual sound source heard by the listener and the positions of the listener's ears. Sound image localization can be achieved by playing back the data sound convolved with such a filter from two-channel speakers.

[0029] 4 is a diagram showing an example of the hardware configuration of the acoustic control device 1 of the second embodiment. The acoustic control device 1 of the second embodiment has, as its hardware configuration, for example, a processor 101, a memory 102, a storage 103, an acoustic processing circuit 104, and speakers 105a and 105b of two or more channels. Here, as with the first embodiment, the acoustic control device 1 of the second embodiment may have hardware elements other than those shown in FIG. 4.

[0030] The configurations of the processor 101, memory 102, and storage 103 may be the same as those in the first embodiment, and therefore, a description thereof will be omitted.

[0031] The acoustic processing circuit 104 is a circuit configured to operate together with the processor 101 as the acoustic processing unit 20 and the playback control unit 30, to perform acoustic processing on input sound data, and to play back the acoustically processed sound data on the speakers 105 a and 105 b. The acoustic processing circuit 104 of the second embodiment is configured to be able to perform sound image localization processing.

[0032] The speakers 105a and 105b are two-channel speakers for reproducing interference sound data. For example, the speaker 105a can function as a left speaker located on the front left side of the listener, and the speaker 105b can function as a right speaker located on the front right side of the listener.

[0033] Next, the operation of the acoustic control device 1 of the second embodiment will be described. Fig. 5 is a flowchart showing the operation of the acoustic control device 1 of the second embodiment. The operation of Fig. 5 is controlled by the processor 101. In the description of Fig. 5, the same processing as in Fig. 3 will be omitted as appropriate.

[0034] In step S11, the processor 101 recognizes the situation in the space including the system and collects information for determining whether or not to output an interfering sound. The mechanism for performing step S11 may or may not be included in the system of the control device.

[0035] In step S12, processor 101 determines whether or not it is necessary to output an interfering sound. If it is determined in step S12 that it is not necessary to output an interfering sound, the process proceeds to step S18. If it is determined in step S12 that it is necessary to output an interfering sound, the process proceeds to step S13.

[0036] In step S13, the processor 101 generates interference sound data. For example, the processor 101 obtains the interference sound data from the storage 103.

[0037] In step S14, the processor 101 outputs the interfering sound data to the acoustic processing circuit 104. Then, the processor 101 causes the acoustic processing circuit 104 to perform a volume adjustment process on the interfering sound data.

[0038] In step S15, the processor 101 causes the sound processing circuit 104 to perform frequency band adjustment processing on the interference sound data.

[0039] In step S16, the processor 101 causes the acoustic processing circuit 104 to perform sound image localization processing on the interfering sound data. The acoustic processing circuit 104 generates interfering sound data for the L channel and interfering sound data for the R channel by applying a filter so that sounds corresponding to a virtual sound source placed at a predetermined position around the listener, for example, at the position of the listener's left ear, are reproduced from the speakers. Then, in step S17, the acoustic processing circuit 104 reproduces the interfering sound data for the L channel from the speaker 105a and the interfering sound data for the R channel from the speaker 105b.

[0040] In step S18, processor 101 determines whether or not to end the operation of Fig. 5. If it is not determined in step S18 that the operation of Fig. 5 is to be ended, processor 101 returns the process to step S12. If it is determined in step S19 that the operation of Fig. 5 is to be ended, processor 101 ends the operation of Fig. 5.

[0041] As described above, in the second embodiment, sound image localization processing is performed as processing for an interfering sound. For example, as shown in FIG. 6, if speakers 105a and 105b emitting an interfering sound are located to the left and right in front of a listener U, the listener U would normally hear a target sound from a target sound source X through his / her left ear, while also hearing an interfering sound from the front. In contrast, by performing sound image localization processing, the listener U may be given the illusion that the interfering sound is coming from a virtual sound source A1 separate from the positions of the original speakers 105a and 105b. In this way, in the second embodiment, a state is realized in which the interfering sound is heard from directions including directions from which it would not naturally occur. This is expected to focus the listener's attention on the interfering sound, thereby enhancing the interfering effect.

[0042] Here, in the example of Fig. 5, in addition to sound image localization processing, both volume adjustment processing and frequency band adjustment processing are performed as acoustic processing. In contrast to this, in Fig. 5, in addition to sound image localization processing, only one of volume adjustment processing and frequency band adjustment processing may be performed as acoustic processing, or neither may be performed. Furthermore, interfering sound data that has been subjected to sound image localization processing and interfering sound data that has not been subjected to sound image localization processing may be mixed and played simultaneously from speakers 105a and 105b. In this case, the listener U may have the illusion that he or she is hearing interfering sounds from two directions.

[0043] (Third embodiment) Next, a third embodiment will be described. Here, a description of the same parts of the third embodiment as those of the first and second embodiments will be omitted. That is, the basic functional blocks shown in FIG. 1 can be applied to the third embodiment as well. However, also in the third embodiment, the acoustic processing unit 20 can perform sound image localization processing and phase adjustment processing in addition to volume adjustment processing and frequency band adjustment processing. Phase adjustment processing is processing for changing the phase of sound. Furthermore, the hardware configuration of the acoustic control device 1 in the third embodiment can basically be the same as the configuration shown in FIG. 4. However, the acoustic processing circuit 104 in the third embodiment is configured to be able to perform phase adjustment processing.

[0044] Next, the operation of the acoustic control device 1 of the third embodiment will be described. Fig. 7 is a flowchart showing the operation of the acoustic control device 1 of the third embodiment. The operation of Fig. 7 is controlled by the processor 101. In the description of Fig. 7, the same processing as in Fig. 3 or Fig. 5 will be omitted as appropriate.

[0045] In step S21, the processor 101 recognizes the situation in the space including the system and collects information for determining whether or not to output an interfering sound. The mechanism for performing step S21 may or may not be included in the system of the control device.

[0046] In step S22, processor 101 determines whether or not it is necessary to output an interfering sound. If it is determined in step S22 that it is not necessary to output an interfering sound, the process proceeds to step S28. If it is determined in step S22 that it is necessary to output an interfering sound, the process proceeds to step S23.

[0047] In step S23, the processor 101 generates interference sound data. For example, the processor 101 obtains the interference sound data from the storage 103.

[0048] In step S24, the processor 101 copies the interfering sound data multiple times. The number of copies of the interfering sound data to be copied may be any number.

[0049] In step S25, the processor 101 outputs the original interfering sound data and the duplicated interfering sound data to the acoustic processing circuit 104. Then, the processor 101 causes the acoustic processing circuit 104 to perform a phase adjustment process on each of the interfering sound data. The acoustic processing circuit 104 imparts a different phase, i.e., a playback time delay, to each of the duplicated interfering sound data. It is desirable that the phase difference imparted to each of the interfering sound data be set so that the interfering sounds that are virtually heard simultaneously by the listener do not simply result in an echo state.

[0050] In step S26, the processor 101 causes the acoustic processing circuit 104 to perform different sound image localization processes on the interfering sound data. The acoustic processing circuit 104 generates interfering sound data for the L channel and interfering sound data for the R channel for each interfering sound data so that the interfering sounds correspond to sounds in which virtual sound sources are placed at different positions. Here, it is desirable that the positions of the virtual sound sources are appropriate positions that can be recognized as clearly different directions. Then, in step S27, the acoustic processing circuit 104 mixes the sound data for the L channel and plays it back from the speaker 105a, and plays back the interfering sound data for the R channel from the speaker 105b.

[0051] In step S28, processor 101 determines whether or not to end the operation in Fig. 7. If it is not determined in step S28 that the operation in Fig. 7 is to be ended, processor 101 returns the process to step S22. If it is determined in step S28 that the operation in Fig. 7 is to be ended, processor 101 ends the operation in Fig. 7.

[0052] As described above, in the third embodiment, the processing applied to the interfering sound involves assigning different phases to a plurality of interfering sound data and localizing sound images in different localization directions. As a result, as shown in Fig. 8, the listener U is simultaneously listening to interfering sounds with slightly different playback timings from virtual sound sources A1, A2, A3, and A4 virtually positioned in different directions around the listener U. This puts the listener in a state where he or she is surrounded by sounds that are extremely difficult to hear, making it possible to prevent the listener from hearing the content of the target sound from target sound source X that the listener is originally trying to hear. Here, in Fig. 8, there are four virtual sound sources. The number of virtual sound sources is not limited to four.

[0053] In the third embodiment, the volume adjustment process and the frequency band adjustment process may be performed on each of the interference sound data.

[0054] (Fourth embodiment) Next, a fourth embodiment will be described. Here, a description of the same parts of the fourth embodiment as those of the first to third embodiments will be omitted. That is, the basic functional blocks shown in FIG. 1 can be applied to the fourth embodiment as well. Furthermore, the hardware configuration of the acoustic control device 1 in the fourth embodiment can basically be the configuration shown in FIG. 4.

[0055] Next, the operation of the acoustic control device 1 of the fourth embodiment will be described. Fig. 9 is a flowchart showing the operation of the acoustic control device 1 of the fourth embodiment. The operation of Fig. 9 is controlled by the processor 101. In the description of Fig. 9, the same processing as in Fig. 3, Fig. 5 or Fig. 7 will be omitted as appropriate.

[0056] In step S31, the processor 101 recognizes the situation in the space including the system and collects information for determining whether or not to output an interfering sound. The mechanism for performing step S31 may or may not be included in the system of the control device.

[0057] In step S32, processor 101 determines whether or not it is necessary to output an interfering sound. If it is determined in step S32 that it is not necessary to output an interfering sound, the process proceeds to step S37. If it is determined in step S32 that it is necessary to output an interfering sound, the process proceeds to step S33.

[0058] In step S33, the processor 101 generates interference sound data. For example, the processor 101 obtains the interference sound data from the storage 103.

[0059] In step S34, the processor 101 changes the localization direction of the interfering sound data. Specifically, the processor 101 instructs the acoustic processing circuit 104 to change the filter to be applied for sound image localization processing. The filter is changed by continuously or randomly selecting filters corresponding to different localization directions along a predetermined trajectory.

[0060] In step S35, the processor 101 causes the acoustic processing circuit 104 to perform sound image localization processing on the interfering sound data using the localization direction changed in step S34. The acoustic processing circuit 104 generates interfering sound data for the L channel and interfering sound data for the R channel by applying the changed filter to the interfering sound data. Then, in step S36, the acoustic processing circuit 104 reproduces the interfering sound data for the L channel from the speaker 105a and the interfering sound data for the R channel from the speaker 105b.

[0061] In step S37, processor 101 determines whether or not to end the operation in Fig. 9. If it is not determined in step S37 that the operation in Fig. 9 is to be ended, processor 101 returns the process to step S32. If it is determined in step S37 that the operation in Fig. 9 is to be ended, processor 101 ends the operation in Fig. 9.

[0062] As described above, in the fourth embodiment, sound image localization processing in different localization directions is sequentially performed on the same interfering sound data as processing for the interfering sound. As a result, as shown in Fig. 10, a state is created in which the listener U is in the center of a space where the sound source A1 moves around the listener U along a trajectory O, which is a rare occurrence under normal circumstances. This causes the listener U to be more conscious of the interfering sound, which may result in the listener U being unable to hear the target sound from the target sound source X that the listener U is trying to hear.

[0063] 10, sound image localization processing is performed on one piece of interfering sound data. In contrast to this, in the fourth embodiment, sound image localization processing may be performed on a plurality of pieces of interfering sound data to successively change the localization direction. In this case, the acoustic processing circuit 104 mixes the interfering sound data that have been subjected to the respective sound image localization processing and plays the resulting mixture from the speakers 105a and 105b.

[0064] In the fourth embodiment, the volume adjustment process and the frequency band adjustment process may be performed on each of the interference sound data.

[0065] (Fifth embodiment) Next, a fifth embodiment will be described. Here, a description of the same parts of the fifth embodiment as those of the first to fourth embodiments will be omitted. That is, the basic functional blocks shown in FIG. 1 can be applied to the fifth embodiment as well. Furthermore, the hardware configuration of the acoustic control device 1 in the fifth embodiment can basically be applied to the configuration shown in FIG. 4. However, in the fifth embodiment, the speakers 105a and 105b operate as sound sources for reproducing counter sound data, not interfering sound data. The counter sound data is not a sound that interferes with the audibility of the target sound, but data containing information about the counter sound intended to allow the listener to hear its contents as a counter to the target sound. The counter sound is, for example, a sound containing a message to alert the listener. Therefore, in the fifth embodiment, the sound acquisition unit 10 acquires counter sound data instead of interfering sound data.

[0066] Next, the operation of the acoustic control device 1 of the fifth embodiment will be described. Fig. 11 is a flowchart showing the operation of the acoustic control device 1 of the fifth embodiment. The operation of Fig. 11 is controlled by the processor 101. In the description of Fig. 11, the same processing as in Fig. 3, Fig. 5, Fig. 7 or Fig. 9 will be omitted as appropriate.

[0067] In step S41, processor 101 recognizes the situation in the space including this system and collects information for determining whether or not to output a counter sound. The situation in the space including this system is recognized and information for determining whether or not to output a counter sound is collected. The mechanism for implementing step S41 may or may not be included in the system of this control device.

[0068] In step S42, processor 101 determines whether or not it is necessary to output a counter sound. If it is determined in step S42 that it is not necessary to output a counter sound, the process proceeds to step S47. If it is determined in step S42 that it is necessary to output a counter sound, the process proceeds to step S43.

[0069] In step S43, the processor 101 generates the opposing sound data. For example, the processor 101 obtains the opposing sound data from the storage 103.

[0070] In step S44, the processor 101 changes the localization direction of the opposing sound data. Specifically, it instructs the acoustic processing circuit 104 to change the filter to be applied for sound image localization processing. The filter is changed by continuously or randomly selecting filters corresponding to different localization directions along a predetermined trajectory. Here, the opposing sound data is sound data intended to allow the listener to hear the content. For this reason, it is desirable that the amount of change in the localization direction of the opposing sound data be smaller than the amount of change in the localization direction of the interfering sound data.

[0071] In step S45, the processor 101 causes the acoustic processing circuit 104 to perform sound image localization processing on the opposing sound data using the localization direction changed in step S44. The acoustic processing circuit 104 generates opposing sound data for the L channel and opposing sound data for the R channel by applying the changed filter to the opposing sound data. Then, in step S46, the acoustic processing circuit 104 plays the opposing sound data for the L channel from the speaker 105a and the opposing sound data for the R channel from the speaker 105b.

[0072] In step S47, processor 101 determines whether or not to end the operation of Fig. 11. If it is not determined in step S47 that the operation of Fig. 11 is to be ended, processor 101 returns the process to step S42. If it is determined in step S47 that the operation of Fig. 11 is to be ended, processor 101 ends the operation of Fig. 11.

[0073] As described above, in the fifth embodiment, sound image localization processing in different localization directions is sequentially performed on the same counter sound data as processing for the counter sound. As a result, as shown in Fig. 12, a state is created in which the listener U is in the center of a space where the counter sound source α moves around the listener U along a trajectory O, a state that rarely occurs under normal circumstances. This causes the listener U to be more conscious of the counter sound, which may result in the listener U being unable to hear the target sound from the target sound source X that the listener U is trying to hear.

[0074] Here, in the fifth embodiment, volume adjustment processing and frequency band adjustment processing may be performed on the counter sound data. Furthermore, the counter sound is a sound intended to be heard by the listener U. Therefore, the counter sound may be given directivity toward the listener U. For example, if there are three or more speakers, directivity may be given by area sound pressure control that combines acoustic power control and phase delay control.

[0075] (Modification of the fifth embodiment) Next, a modified example of the fifth embodiment will be described. In the fifth embodiment, an example is shown in which opposing sound data is localized and reproduced instead of interfering sound data. In contrast to this, as shown in FIG. 13, in addition to the opposing sound source α, an interfering sound source A1 may also be localized and reproduced. The sound image localization of the interfering sound source A1 may be performed by any of the methods described in the second to fourth embodiments. FIG. 13 shows an example in which the sound image of the interfering sound source A1 is localized by the method described in the fourth embodiment. By simultaneously reproducing the interfering sound and the opposing sound, the effect of preventing the listener U from hearing the target sound from the target sound source X that he or she is trying to hear is further enhanced.

[0076] Here, the interfering sound is a sound that becomes noise to the listener U, whereas the opposing sound is a sound that is intended to be heard by the listener U. When the interfering sound and the opposing sound are played back simultaneously, there is a possibility that the audibility of the opposing sound may be hindered by the interfering sound. For this reason, in the modified example of the fifth embodiment, it is more desirable that the opposing sound source a be given directivity D directed toward the listener U as shown in Fig. 13. For example, if there are three or more speakers, the directivity D is given by area sound pressure control that combines acoustic power control and phase delay control.

[0077] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0078] 1 Acoustic control device, 10 Sound acquisition unit, 20 Acoustic processing unit, 30 Playback control unit, 101 Processor, 102 Memory, 103 Storage, 104 Acoustic processing circuit, 105, 105a, 105b Speakers.

Claims

1. a sound acquisition unit that acquires interfering sound data including information on interfering sounds that act as noise that interferes with the listener's ability to hear the target sound; an acoustic processing unit that performs acoustic processing on the acquired interfering sound data to interfere with the audibility of the target sound; a playback control unit that plays back the acoustically processed interference sound data from an output device; An acoustic control device comprising:

2. The acoustic processing unit performs at least one of a volume adjustment process for the interfering sound data, a frequency band adjustment process, and a sound image localization process for the interfering sound data, as the acoustic processing. The acoustic control device according to claim 1 .

3. The acoustic processing unit includes: Duplicating the interference sound data; different phases are assigned to the plurality of interfering sound data obtained by duplication, and sound image localization processing is performed in different directions. The acoustic control device according to claim 1 .

4. The acoustic processing unit includes: Sequentially performing sound image localization processing in different directions on the same interfering sound data. The acoustic control device according to claim 1 .

5. a sound acquisition unit that acquires counter sound data including content that a listener hears as a counter to the target sound; a sound processing unit that performs sound processing on the acquired opposing sound data to disrupt the listener's hearing of the target; a playback control unit that plays back the acoustically processed opponent sound data from an output device; An acoustic control device comprising:

6. The sound processing unit performs at least one of a volume adjustment process for the opposing sound data, a frequency band adjustment process, and a sound image localization process for the opposing sound data, as the sound processing. The acoustic control device according to claim 5 .

7. The acoustic processing unit further performs a process of imparting directivity toward the listener to the opposing sound data. The acoustic control device according to claim 5 .

8. a sound acquisition unit that acquires interfering sound data including information on an interfering sound that acts as noise to interfere with the listener's hearing of the target sound, and counter sound data including content to be heard by the listener as a counter to the target sound; a sound processing unit that performs sound processing on the acquired interfering sound data and the acquired opposing sound data to interfere with the audibility of the target sound; a playback control unit that plays back the acoustically processed interfering sound data and the opposing sound data from an output device; An acoustic control device comprising:

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