JP6957362B2 - Privacy protection system - Google Patents

Description

The present invention relates to a privacy protection system.

Conventionally, in a moving body such as an automobile, hands-free calling has been put into practical use so that the occupant of the moving body can make a call without holding a telephone by hand. In the case of a hands-free call in a mobile body, if the received sound from the other party is reproduced at a relatively loud volume from the speaker, this reproduced sound may leak to the outside. As a countermeasure against sound leakage from headphones, earphones, or speakers of mobile phones, for example, a technique for reducing the volume of reproduced sound when it is determined that there is sound leakage has been proposed (Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2007-43231 Japanese Unexamined Patent Publication No. 2008-72677

However, the techniques disclosed in Patent Documents 1 and 2 are insufficient as a countermeasure against sound leakage during hands-free calling in a mobile body, and when the reproduced sound of hands-free calling leaks to the outside, it is reproduced by an outside person. There is a problem from the viewpoint of privacy protection because the content of the sound may be heard.
The present invention has been made in view of the above circumstances, and provides a privacy protection system capable of protecting privacy when the reproduced sound output to a moving occupant leaks to the outside. The purpose is.

In order to achieve the above object, the privacy protection system of the present invention is a privacy protection system mounted on a moving body and outputting a reproduced sound to a occupant of the moving body in a predetermined space around the occupant. When the sound collecting unit that collects the sound outside the predetermined space and the level of the sound collected by the sound collecting unit are equal to or higher than the predetermined level, the reproduced sound is heard outside the predetermined space. It is characterized by including a processing unit that executes a difficult-to-listen process.

Further, when the level of the sound collected by the sound collecting unit is equal to or higher than the predetermined level, the processing unit described the reproduced sound and the sound collected by the sound collecting unit based on the comparison result. It may be configured to execute the listening difficulty process.

Further, the processing unit converts the frequency of the reproduced sound and the sound collected by the sound collecting unit, respectively, and compares the frequency component of the reproduced sound with the frequency component of the sound collected by the sound collecting unit. It may be configured to be used.

Further, the processing unit recognizes the reproduced sound and the sound collected by the sound collecting unit, respectively, and obtains the voice recognition result of the reproduced sound and the voice recognition result of the sound collected by the sound collecting unit. May be configured to compare.

Further, a sound output unit that outputs sound toward the outside of the predetermined space may be provided, and the listening difficulty processing may be configured to output a masking sound that masks the reproduced sound by the sound output unit.

Further, the listening difficulty processing may be configured to reduce the volume of the reproduced sound.

Further, a speed acquisition unit for acquiring the speed of the moving body may be provided, and the processing unit may be configured to execute the listening difficulty processing when the speed acquired by the speed acquisition unit is less than a predetermined speed.

Further, the current position acquisition unit for acquiring the current position of the moving body is provided, and the processing unit makes it difficult to hear when the current position of the moving body acquired by the current position acquisition unit is a predetermined position. It may be configured to execute the process.

Further, the reproduced sound may be configured to be a received sound of a hands-free call.

According to the present invention, the sound outside the predetermined space around the occupant of the moving body is collected, and when the collected sound is loud, the reproduced sound is hard to hear outside the predetermined space. It is possible to protect privacy when the reproduced sound output to the occupant of the vehicle leaks to the outside.

The block diagram of the privacy protection system of 1st Embodiment. Schematic diagram of a vehicle equipped with a privacy protection system. The flowchart which shows the operation of the privacy protection system of 1st Embodiment. An example of the frequency spectrum of sound leaking out of the vehicle. An example of a frequency spectrum in which the masking sound overlaps with the sound leaking out of the vehicle. Another example of a frequency spectrum in which the masking sound overlaps the sound leaking out of the vehicle. An example of time-dependent changes in the level of the sound collection signal. The block diagram of the privacy protection system of 2nd Embodiment. The flowchart which shows the operation first half of the privacy protection system of 2nd Embodiment. The flowchart which shows the latter half (frequency component comparison) of the operation of the privacy protection system of 2nd Embodiment. The flowchart which shows the latter half of operation (speech recognition result comparison) of the privacy protection system of 2nd Embodiment. An example of the frequency spectrum of the reproduced sound signal and the collected sound signal. A comparative example of the frequency components of the reproduced sound signal and the sound collecting signal shown in FIG. An example of time-dependent changes in the level of the reproduced sound signal and the level of the collected sound signal. A comparative example of the frequency components of the reproduced sound signal and the sound collecting signal shown in FIG. Other examples of temporal changes in the level of the reproduced sound signal and the level of the collected sound signal. A comparative example of the frequency components of the reproduced sound signal and the sound collecting signal shown in FIG. A comparison example of the voice recognition result of the reproduced sound signal and the sound collecting signal.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment)
FIG. 1 is a configuration diagram of the privacy protection system 10 of the first embodiment. FIG. 2 is a schematic view of a vehicle 1 on which the privacy protection system 10 is mounted.
The privacy protection system 10 of the first embodiment is mounted on a vehicle 1 (corresponding to a mobile body of the present invention) provided with a hands-free communication device 20. When the privacy protection system 10 determines that the reproduced sound of the other party's received sound is leaked to the outside of the vehicle 1 during a hands-free call, it is difficult for a person outside the vehicle 1 to hear the content of the reproduced sound. It has a function to perform listening difficulty processing. The privacy protection system 10 may be configured as a dedicated device, may be configured as a part of an in-vehicle device (for example, an ECU (Electronic Control Unit)) mounted on the vehicle 1, or may be configured as an in-vehicle device. It may be configured by using a part of the function.

The hands-free calling device 20 is a device that enables an occupant (particularly, a driver during a driving operation) to make a call without holding a telephone (for example, a mobile phone or a smartphone) while the vehicle 1 is traveling. The hands-free calling device 20 collects the voice emitted by the occupant by a microphone (not shown) provided in the vehicle 1 and transmits the collected voice to the other party. Further, the hands-free calling device 20 reproduces the voice from the other party by the in-vehicle speaker 30 provided in the vehicle 1. The hands-free communication device 20 performs short-range wireless communication using Bluetooth (registered trademark) with, for example, a mobile phone or the like, and transmits / receives an audio signal. The hands-free calling device 20 may be configured to make a hands-free calling using a vehicle telephone mounted in advance in the vehicle 1.

The privacy protection system 10 is controlled by the control unit 40. The control unit 40 is an electronic circuit unit composed of a CPU (Central Processing Unit) 50, a memory 60, various interface circuits (not shown), and the like. The CPU 50 reads and executes the control program 61 of the privacy protection system 10 stored in the memory 60, so that the sound leakage determination unit 51 (including the level determination unit 51a), the masking control unit 52, the volume control unit 53, It functions as an alarm control unit 54. In the first embodiment, the CPU 50 corresponds to the processing unit of the present invention.

A hands-free communication device 20 is connected to the control unit 40. During a hands-free call, the hands-free calling device 20 acquires the call sound of the other party from a mobile phone or the like, and transmits a reproduced sound signal for reproducing the call sound to the control unit 40. When the control unit 40 receives the reproduced sound signal, the control unit 40 transmits the reproduced sound signal and the volume information to the amplifier 31. The volume information is information on the default volume, the volume set according to the volume adjustment operation for the volume control unit (not shown) by the occupant, or the volume set by the volume control of the control unit 40 described later. The default volume is set in advance so that the occupant can sufficiently hear it even if there is road noise or the like transmitted to the vehicle interior while the vehicle 1 is traveling.

A vehicle speed sensor 21 (corresponding to the speed acquisition unit of the present invention) and a navigation device 22 (corresponding to the current position acquisition unit of the present invention) are connected to the privacy protection system 10.

The vehicle speed sensor 21 detects the vehicle speed of the vehicle 1 and transmits a vehicle speed signal to the control unit 40.

The navigation device 22 has a function of detecting the current position, the traveling direction, and the like of the vehicle 1. The navigation device 22 transmits a current position signal indicating the current position of the vehicle 1 to the control unit 40. The navigation device 22 includes a map database 22a that stores various map information. The navigation device 22 acquires map information (for example, urban areas (including downtown areas), suburbs, and mountainous areas) around the current position of the vehicle 1 from the map database 22a, and transmits the map information signal to the control unit 40.

A microphone 24 (corresponding to the sound collecting unit of the present invention) is connected to the control unit 40 via a noise canceller 23. The microphone 24 collects the sound outside the vehicle 1, converts the collected sound into an electric signal, and transmits the collected sound to the noise canceller 23 as a sound collecting signal. For example, the microphone 24 collects external sounds of the vehicle 1 including the sound of the reproduced sound output from the in-vehicle speaker 30 leaking out of the vehicle interior during a call by the hands-free communication device 20. The microphone 24 is attached to the rear of the left door mirror 1a or the rear of the vicinity of the left door mirror 1a as shown in FIG. 2, for example, in order to suppress the influence of wind noise and the like while the vehicle 1 is traveling. Reference numeral 1b in FIG. 2 indicates the steering of the vehicle 1. The reason why the microphone 24 is arranged on the left side of the vehicle 1 is that if the vehicle is traveling on the left side, the sidewalk is arranged on the left side of the roadway and there is a high possibility that a person is on the left side of the vehicle 1, so that the microphone 24 is arranged around the vehicle 1. This is because the sound is collected on the side that is likely to be heard by people. Further, it is preferable that the microphone 24 is arranged in the vicinity of the in-vehicle speaker 30. When the noise canceller 23 receives the sound collection signal from the microphone 24, the noise canceller 23 removes ambient noise (for example, noise in a frequency band other than the human voice frequency band) from the sound collection signal, and the sound collection signal after removing the noise. Is transmitted to the control unit 40. The noise canceller 23 can be turned ON / OFF, and when it is OFF, the sound collecting signal from the microphone 24 is transmitted to the control unit 40 as it is.

An in-vehicle speaker 30 is connected to the control unit 40 via an amplifier 31. When the amplifier 31 receives the reproduced sound signal and the volume information from the control unit 40, the amplifier 31 amplifies the analog audio signal corresponding to the reproduced sound signal according to the volume information and transmits it to the in-vehicle speaker 30. When the vehicle interior speaker 30 receives the analog audio signal, it converts the analog audio signal into audio (reproduced sound) and outputs the analog audio signal. At least one in-vehicle speaker 30 is provided in the vehicle interior of the vehicle 1, and for example, as shown in FIG. 2, one is provided on each of the left and right side portions (for example, a door) in the vehicle interior of the vehicle 1. In the present embodiment, the passenger compartment of the vehicle 1 corresponds to a predetermined space around the occupant of the present invention.

An external speaker 32 (corresponding to the sound output unit of the present invention) is connected to the control unit 40 via an amplifier 33. When the amplifier 33 receives the masking sound signal from the control unit 40, which will be described later, the amplifier 33 amplifies the analog audio signal corresponding to the masking sound signal according to the volume adjusted by the control unit 40, and transmits the analog audio signal to the external speaker 32. When the vehicle external speaker 32 receives the analog audio signal, it converts the analog audio signal into audio (masking sound) and outputs the analog audio signal. At least one external speaker 32 is provided in the vehicle 1, and for example, as shown in FIG. 2, one speaker 32 is provided on the left side side (for example, a door) of the vehicle 1. The reason why the vehicle external speaker 32 is arranged on the left side of the vehicle 1 is that if the vehicle is traveling on the left side, there is a high possibility that a person is on the left side of the vehicle 1, so the vehicle is based on the masking sound output from the vehicle external speaker 32. This is to make it difficult for people around 1 to hear the content of the reproduced sound of the hands-free call. Further, as shown in FIG. 2, for example, the vehicle external speaker 32 is provided behind the vehicle internal speaker 30 in the vehicle 1. Further, the vehicle external speaker 32 is provided, for example, in the lower part of the vehicle 1. The vehicle external speaker 32 is arranged so that the sound is output toward the outside of the vehicle 1.

A display 34 is connected to the control unit 40. The display 34 is a liquid crystal display of a touch panel shared with, for example, a navigation device 22 and the like. When the display 34 receives the alarm display signal from the control unit 40 described later, the display 34 displays the alarm information based on the alarm display signal.

The control unit 40 receives the vehicle speed signal, the current position signal, the map information signal, the reproduced sound signal, and the sound collecting signal described above. The control unit 40 stores the sound collecting signals for a predetermined time as sound collecting data 62 in the memory 60. The predetermined time is set in advance.

The sound leakage determination unit 51 has a level determination unit 51a. The level determination unit 51a determines whether or not the reproduced sound is leaking to the outside of the vehicle 1 by using the sound collection data 62 (time series data of the sound collection signal).

When the sound leakage determination unit 51 determines that the reproduced sound may have leaked to the outside of the vehicle 1, the masking control unit 52 masks the reproduced sound leaked to the outside as a listening difficulty process. Is controlled to be output from the external speaker 32. Further, the sound leakage determination unit 51 determines whether or not the listening difficulty processing is necessary based on the vehicle speed signal, the current position signal, and the map information signal.

When the level determination unit 51a of the sound leakage determination unit 51 determines that the reproduced sound is leaking to the outside of the vehicle 1, the volume control unit 53 controls to reduce the volume of the reproduced sound as a listening difficulty process. ..

When the sound leakage determination unit 51 determines that the reproduced sound is leaking to the outside of the vehicle 1, the alarm control unit 54 controls the display 34 to display the alarm information regarding the sound leakage.

A series of operations of the privacy protection system 10 will be described with reference to FIG. FIG. 3 is a flowchart showing the operation of the privacy protection system 10. This series of operations is repeatedly performed when the occupant of the vehicle 1 is performing a hands-free call using the hands-free call device 20.

The control unit 40 receives the current position signal and the map information signal from the navigation device 22, and acquires the current position of the vehicle 1 and the map information around the current position (step S1). In the control unit 40, the sound leakage determination unit 51 determines whether or not the current position of the vehicle 1 is in the urban area (corresponding to the predetermined location of the present invention) (step S2). The urban area has a higher population density than the suburbs and mountainous areas, and is more likely to hear the reproduced sound of the hands-free call leaked from the vehicle 1 than these places. In particular, when the vehicle 1 stops at an intersection or the like, there is a high possibility that the reproduced sound leaked from the vehicle 1 will be heard.

When it is determined that the current position is in the city area (step S2: YES), the control unit 40 receives the vehicle speed signal from the vehicle speed sensor 21 and acquires the vehicle speed of the vehicle 1 (step S3). In the control unit 40, the sound leakage determination unit 51 determines whether or not the vehicle speed is less than a predetermined speed (step S4). The predetermined speed is a threshold value for determining that the vehicle 1 is traveling at a low speed. The predetermined speed is, for example, the speed of a vehicle during slow driving or traffic jam, or the speed of walking of a person. The predetermined speed is set in advance and stored in the memory 60 or the like. When the vehicle 1 is stopped or traveling at a low speed, if the reproduced sound of the hands-free call leaks to the outside of the vehicle 1, a person in the vicinity of the vehicle 1 may hear the content of the reproduced sound. When the vehicle 1 is at high speed, the road noise and the engine noise are loud, and the vehicle 1 also passes in a short time. Therefore, there is almost no possibility that a person in the vicinity of the vehicle 1 will hear the content of the reproduced sound.

When it is determined that the current position is in the city area (step S2: YES) and the vehicle speed is determined to be less than the predetermined speed (step S4: YES), the sound leakage determination unit 51 transmits the reproduced sound of the hands-free call to the outside of the vehicle 1. If there is a leak, there is a high possibility that a nearby person will hear the call, so it is determined that listening difficulty processing is necessary, and the alarm control unit 54 transmits an alarm display signal indicating alarm information to the display 34 ( Step S5). When the display 34 receives the alarm display signal, the display 34 displays the alarm information. This alarm information indicates, for example, that the reproduced sound of the hands-free call may be heard outside the vehicle 1, and prompts the user to close the window of the vehicle 1 if the window is open. Information. When the occupant of the vehicle 1 closes the window in response to this alarm information, the leakage of the reproduced sound to the outside is suppressed.
When the window of the vehicle 1 is open, the control unit 40 may automatically close the window.

The masking control unit 52 generates a masking sound signal for outputting the masking sound, and transmits this masking sound signal to the amplifier 33 (step S6). The amplifier 33 amplifies the masking sound signal so as to have a predetermined volume, converts it into an analog audio signal, and transmits this analog audio signal to the external speaker 32. Upon receiving this analog audio signal, the vehicle external speaker 32 outputs a masking sound at a predetermined volume. The predetermined volume is, for example, a preset volume. By outputting the masking sound to the outside of the vehicle 1, it is difficult for the surrounding people to hear the content of the reproduced sound of the hands-free call that may be leaking to the outside of the vehicle 1.

The masking sound is a sound for ensuring the volume of the reproduced sound of the hands-free call in the vehicle interior of the vehicle 1 and making it difficult for the surrounding people to hear the reproduced sound leaked to the outside. The masking sound is, for example, a noise sound source of the vehicle 1 such as an engine sound or a road noise, or a sound similar to white noise. The masking sound may be, for example, music set by the occupant or a voice message such as "I'm on the phone." The masking sound is preferably a sound in which the sound level of the human voice band is strengthened in order to make it difficult to hear the content of the reproduced sound. By using a masking sound with this band strengthened, the volume of the masking sound can be suppressed. The volume of the masking sound is equal to or lower than the predetermined level used by the level determination unit 51a.

FIG. 4 shows an example of the frequency spectrum of the sound leaked to the outside of the vehicle 1. FIG. 5 shows an example of a frequency spectrum in which a masking sound overlaps with a sound leaking to the outside of the vehicle 1. FIG. 6 shows another example of the frequency spectrum in which the masking sound is superimposed on the sound leaked to the outside of the vehicle 1. In FIGS. 4, 5 and 6, the horizontal axis is time and the vertical axis is frequency.

The frequency spectrum FS1 shown in FIG. 5 is a frequency spectrum when a masking sound is superimposed on the sound of the frequency spectrum FS0 shown in FIG. Comparing the frequency spectrum FS0 shown in FIG. 4 with the frequency spectrum FS1 shown in FIG. 5, masking sounds are included in the time zones indicated by the arrows T1, T2, T3, and T4 in FIG. A part of the frequency spectrum component of the sound is lost, and the content of the sound of the frequency spectrum FS0 shown in FIG. 4 becomes difficult to hear.
Further, the frequency spectrum FS2 shown in FIG. 6 is a frequency spectrum when a masking sound similar to the running noise of a vehicle such as an engine sound is superimposed on the sound of the frequency spectrum FS0 shown in FIG. Comparing the frequency spectrum FS0 shown in FIG. 4 with the frequency spectrum FS2 shown in FIG. 6, the masking sound is included in the low frequency band indicated by the arrow F1 in FIG. Is hard to hear as a whole.

Returning to FIG. 3, the control unit 40 acquires the sound collection signal from the noise canceller 23 and stores the sound collection signal as sound collection data 62 in the memory 60 (step S7). The level determination unit 51a of the sound leakage determination unit 51 determines whether or not the level of the sound collection signal is equal to or higher than a predetermined level (step S8). The predetermined level is a threshold value for determining whether or not the sound leaked to the outside of the vehicle 1 is loud. The predetermined level is a sound level that causes annoyance to people around the vehicle 1. The predetermined level is preset and stored in memory 60, for example.

FIG. 7 shows an example of the time change of the level of the sound collection signal C collected by the microphone 24. In FIG. 7, the horizontal axis is time and the vertical axis is the sound signal level. FIG. 7 shows a predetermined level SH. In the case of the example shown in FIG. 7, the sound collecting signal C exceeds the predetermined level SH in the time zone indicated by the reference numerals T5 and T6. During these time zones T5 and T6, loud noise is leaking from the vehicle 1 to the outside.

Returning to FIG. 3, when it is determined that the level of the sound collecting signal is equal to or higher than the predetermined level (step S8: YES), the sound leakage determination unit 51 determines that the sound is leaking to the outside of the vehicle 1, and the volume control unit 53. Outputs a command to lower the volume of the reproduced sound signal to the amplifier 31 (step S9). When the volume is automatically lowered, the volume is gradually lowered by a predetermined amount up to the preset lower limit volume. In response to this command, the amplifier 31 generates an analog audio signal that amplifies the reproduced sound signal so that the volume is lowered by one step from the previous time, and transmits this analog audio signal to the in-vehicle speaker 30. The vehicle interior speaker 30 outputs a reproduced sound whose volume is lowered by one step from the previous time. As a result, the volume of the reproduced sound of the hands-free call is gradually reduced, and the sound leaking to the outside of the vehicle 1 is also reduced. At this time, the control unit 40 turns on the volume control flag (step S10).

In particular, when the volume of the reproduced sound is lowered to the lower limit volume by the control by the control unit 40, the alarm control unit 54 transmits an alarm display signal indicating the alarm information to the display 34 (step S11). When the display 34 receives the alarm display signal, the display 34 displays the alarm information. This alarm information is, for example, information indicating that the reproduced sound of the hands-free call is leaking to the outside of the vehicle 1 and information for urging the occupant to lower the volume of the reproduced sound by the volume control unit. As a result, the volume of the reproduced sound of the hands-free call may be further lowered by the occupant.

When it is determined that the level of the sound collecting signal is less than a predetermined level (step S8: NO), the volume control unit 53 outputs a command to raise the volume of the reproduced sound signal to the amplifier 31 (step S12). If you want to increase the volume automatically, increase the volume step by step up to the default volume. In response to this command, the amplifier 31 generates an analog audio signal that amplifies the reproduced sound signal so as to raise the volume by one step from the previous time, and transmits this analog audio signal to the in-vehicle speaker 30. The in-vehicle speaker 30 outputs a reproduced sound whose volume is raised by one step from the previous time. As a result, if no loud sound leaks to the outside of the vehicle 1, the playback sound of the hands-free call gradually returns to the default volume. At this time, the control unit 40 turns off the volume control flag (step S13).

When it is determined in step S2 described above that the current position of the vehicle 1 is not in the urban area (step S2: NO) or when it is determined in step S4 that the vehicle speed of the vehicle 1 is equal to or higher than a predetermined speed (step S4: NO), the control unit 40 Determines whether or not the voice control flag is ON (step S14). When it is determined that the voice control in-progress flag is ON, the control unit 40 executes the processes of steps S12 and S13 described above. That is, when the vehicle 1 is traveling in the suburbs or mountainous areas, or when the vehicle 1 is traveling at high speed, the volume of the playback sound of the hands-free call is returned to the default volume.

According to the privacy protection system 10 of the first embodiment, the sound outside the vehicle 1 is collected, and when the collected sound is at a predetermined level or higher, it is difficult to hear the reproduced sound outside the vehicle 1. Privacy can be protected when the reproduced sound output to one occupant leaks to the outside. In particular, in the case where the vehicle 1 has an idling stop function, the engine (not shown) is stopped when the vehicle 1 is stopped, so that the reproduced sound leaked to the outside of the vehicle 1 can be easily heard. By mounting the protection system 10 on the vehicle 1, the privacy protection can be enhanced.

According to the privacy protection system 10, by outputting a masking sound that masks the reproduced sound by the external speaker 32 as a listening difficulty process, the content of the reproduced sound leaked to the outside of the vehicle 1 is transmitted to a person outside the vehicle 1. Can be difficult to hear. In this way, according to the privacy protection system 10, the masking sound makes it difficult for people outside the vehicle 1 to hear, so that the reproduced sound of the hands-free call in the vehicle 1 is not lowered as much as possible. Sufficient volume can be secured.

According to the privacy protection system 10, the volume of the reproduced sound of the hands-free call is reduced as a process for making it difficult to hear, so that the volume of the sound leaked to the outside of the vehicle 1 is lowered, and the reproduced sound leaked to the outside of the vehicle 1 is reduced. The content can be made difficult to be heard by a person outside the vehicle 1, and the degree of inconvenience to a person outside the vehicle 1 due to a loud volume can be reduced.

According to the privacy protection system 10, it is possible to accurately determine whether or not a loud sound is leaking to the outside of the vehicle 1 by determining whether or not the level of the sound collection signal collected by the microphone 24 is equal to or higher than a predetermined level. ..

According to the privacy protection system 10, by acquiring the vehicle speed of the vehicle 1 and determining whether or not the vehicle speed is less than a predetermined speed, when the vehicle speed is low, the sound is reproduced outside the vehicle 1 as compared with the case where the vehicle speed is high. It can be determined that there is a high possibility that sound will leak, and it is possible to determine whether or not the listening difficulty processing is necessary. According to the privacy protection system 10, by acquiring the current position of the vehicle 1 and determining whether or not the current position is in the city area, when the current position is in the city area, the outside of the vehicle 1 is more than outside the city area. It can be determined that there is a high possibility that the reproduced sound leaked to the outside will be heard by an outsider, and it is possible to determine whether or not the listening difficulty processing is necessary. In particular, according to the privacy protection system 10, when the vehicle 1 is at a low speed and the current position of the vehicle 1 is in an urban area, the masking sound is output as a listening difficulty process, so that the vehicle even if the reproduced sound leaks to the outside. It is possible to make it difficult for an outsider to hear the content of the reproduced sound. Further, according to the privacy protection system 10, when the vehicle 1 is at high speed or the current position of the vehicle 1 is outside the city area, there is a possibility that a person outside the vehicle 1 may hear the content of the reproduced sound of the hands-free call. Is low, so privacy can be ensured without outputting the masking sound and lowering the volume of the reproduced sound.

According to the privacy protection system 10, by providing the microphone 24 in the vicinity of the door mirror 1a or the door mirror 1a, the influence of wind noise can be suppressed, and the determination accuracy of the sound leakage determination can be improved.

(Second Embodiment)
FIG. 8 is a configuration diagram of the privacy protection system 70 of the second embodiment. In the configuration shown in FIG. 8, the same components as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted.
The privacy protection system 70 of the second embodiment is mounted on a vehicle 2 (corresponding to a mobile body of the present invention) including a hands-free communication device 20 and an audio device 25. Compared with the privacy protection system 10 of the first embodiment, the privacy protection system 70 is capable of hands-free calling during playback of music or the like by the audio device 25, and the other party during the hands-free call during playback of the music or the like. The difference is that it has a function of determining that the reproduced sound obtained by reproducing the received sound of the above is leaking to the outside of the vehicle 2.

The audio device 25 is a device that reproduces music or the like according to the operation of the occupant. The audio device 25 reproduces music or the like by the in-vehicle speaker 30. For example, the in-vehicle speaker 30 may reproduce only the music by the audio device 25, or may simultaneously reproduce the reproduced sound of the hands-free communication device 20 and the music by the audio device 25.

The privacy protection system 70 is controlled by the control unit 80. The control unit 80 is an electronic circuit unit composed of a CPU 90, a memory 100, various interface circuits (not shown), and the like. The CPU 90 reads and executes the control program 101 of the privacy protection system 70 stored in the memory 100, so that the sound leakage determination unit 91 (including the level determination unit 91a and the comparison unit 91b), the masking control unit 92, and the volume It functions as a control unit 93 and an alarm control unit 94. In the second embodiment, the CPU 90 corresponds to the processing unit of the present invention.

A hands-free communication device 20 and an audio device 25 are connected to the control unit 80. During a hands-free call, the hands-free calling device 20 acquires a playback sound signal of the other party from a mobile phone or the like and transmits the playback sound signal to the control unit 80. The audio device 25 acquires a music signal from a hard disk, a CD (Compact Disk), or the like during playback of music or the like, and transmits the music signal to the control unit 80. When the control unit 80 receives only the call sound signal, the control unit 80 transmits the reproduced sound signal and the volume information to the amplifier 31. When the control unit 80 receives only the music signal, the control unit 80 transmits the music signal and the volume information adjusted by the occupant to the amplifier 31. When the control unit 80 receives the reproduced sound signal and the music signal, the control unit 80 generates a shared sound signal based on the reproduced sound signal and the music signal, and transmits the shared sound signal and the volume information to the amplifier 31. In the volume information of this shared sound signal, the volume of the music signal is lower than the volume of the reproduced sound signal.

The control unit 80 receives a vehicle speed signal, a current position signal, a map information signal, a reproduced sound signal, a music signal, and a sound collecting signal. The control unit 80 stores the sound collecting signals for a predetermined time as sound collecting data 102 in the memory 100. The control unit 80 stores the reproduced sound signal for a predetermined time as the reproduced sound data 103 in the memory 100. The predetermined time is set in advance.

During a hands-free call by the hands-free call device 20, the sound leakage determination unit 91 leaks the sound output from the in-vehicle speaker 30 to the outside of the vehicle 2 based on the vehicle speed signal, the current position signal, and the map information signal. Determine if there is a possibility that it is. The sound leakage determination unit 91 has a level determination unit 91a. When the level determination unit 91a is playing music or the like by the audio device 25, the sound of music or the like output from the in-vehicle speaker 30 based on the sound collection data 102 (time-series data of the sound collection signal) is output to the vehicle 2 Determine if it is leaking to the outside of. Further, the level determination unit 91a determines whether or not the sound is leaking to the outside by using the sound collecting data 102 during the hands-free call by the hands-free call device 20.

The sound leakage determination unit 91 has a comparison unit 91b. When the comparison unit 91b determines that the sound is leaking to the outside by the level determination unit 91a during the hands-free call by the hands-free call device 20, the reproduced sound data 103 (time series of the reproduced sound signal of the hands-free call). The sound collection data 102 (time-series data of the sound collection signal) is compared, and based on the comparison result, it is determined whether or not the reproduced sound of the hands-free call is leaking to the outside of the vehicle 2. As the comparison method in the comparison unit 91b, for example, there are a method of comparing frequency components and a method of comparing voice recognition results.

When the sound leakage determination unit 91 determines that the sound may be leaking to the outside of the vehicle 2, the masking control unit 92 controls to output the masking sound from the external speaker 32 as a listening difficulty process. conduct.

When the comparison unit 91b of the sound leakage determination unit 91 determines that the reproduced sound is leaking to the outside of the vehicle 2, the volume control unit 93 controls to reduce the volume of the reproduced sound as a listening difficulty process.

When the sound leakage determination unit 51 determines that the sound is leaking to the outside of the vehicle 2, the alarm control unit 94 controls the display 34 to display the alarm information regarding the sound leakage.

A series of operations of the privacy protection system 70 will be described with reference to FIGS. 9 to 11. FIG. 9 is a flowchart showing the first half of a series of operations of the privacy protection system 70. FIG. 10 is a flowchart showing the latter half of a series of operations of the privacy protection system 70, and is a case where the comparison method in the comparison unit 91b is a method of comparing frequency components. FIG. 11 is a flowchart showing the latter half of a series of operations of the privacy protection system 70, and is a case where the comparison method in the comparison unit 91b is a method of comparing the voice recognition results. This series of operations is repeated. In the operation description using FIGS. 9 to 11, the same step number is assigned to the same process as in FIG. 3 of the first embodiment, and the description is omitted.

The control unit 80 determines whether or not a hands-free call is in progress based on whether or not a playback sound signal is received from the hands-free call device 20 (step S20). If it is determined that a hands-free call is in progress (step S20: YES), the process proceeds to step S1. In this case, the sound output from the in-vehicle speaker 30 is only the playback sound of the hands-free call by the hands-free call device 20, the playback sound of the hands-free call by the hands-free call device 20, the music by the audio device 25, or the like. It may be the sound of.

When it is determined that the hands-free call is not in progress (step S20: NO), the control unit 80 acquires the sound collection signal from the noise canceller 23 and stores the sound collection signal as sound collection data 102 in the memory 100 (step S21). The level determination unit 91a of the sound leakage determination unit 91 determines whether or not the level of the sound collection signal is equal to or higher than a predetermined level (step S22). In this case, the sound output from the vehicle interior speaker 30 is only the sound of music or the like produced by the audio device 25. The predetermined level is, for example, the same level as the predetermined level used for the level determination in step S8 of FIG. 3 of the first embodiment.

When it is determined that the level of the sound collecting signal is equal to or higher than a predetermined level (step S21: YES), the sound leakage determination unit 51 determines that the sound leakage of music or the like is large, and the alarm control unit 54 outputs an alarm display signal indicating alarm information. It is transmitted to the display 34 (step S23). When the display 34 receives the alarm display signal, the display 34 displays the alarm information. This alarm information is, for example, information indicating that sound such as music is leaking to the outside of the vehicle 2, and when the window of the vehicle 2 is open to the occupant, the window is closed or the volume control unit is used. This is information that encourages the volume of the reproduced sound to be lowered. In this case, since the sound such as music leaks to the outside of the vehicle 2, there are few privacy factors, but since there is a risk of inconvenience to people outside the vehicle 2, the windows are closed and the volume is reduced for the occupants. To urge.

After displaying the alarm information in step S23 or when it is determined in step S22 that the level of the sound collecting signal is less than a predetermined level (step S21: NO), the process proceeds to step S14.

With reference to the flowchart of FIG. 10, the operation when the comparison method in the comparison unit 91b is a method of comparing frequency components will be described.

The control unit 80 acquires a sound collecting signal from the noise canceller 23, and stores the sound collecting signal as sound collecting data 102 in the memory 100 (step S30). Further, the control unit 80 acquires the reproduced sound signal from the hands-free communication device 20 and stores the reproduced sound signal as the reproduced sound data 103 in the memory 100 (step S31). Since the sound collecting signal is a signal obtained by collecting the sound outside the vehicle 2, it includes a noise component outside the vehicle 2. When the vehicle 2 is traveling at high speed, the sound collecting signal has a large running noise and ambient noise of the vehicle 2, but when the vehicle 2 is slow or stopped, the sound collecting signal is affected by the noise at a high speed. Is smaller than in the case of. On the other hand, since the reproduced sound signal is a signal from the hands-free communication device 20 in the vehicle 2, it is not affected by noise.

The level determination unit 91a of the sound leakage determination unit 91 determines whether or not the level of the sound collection signal is equal to or higher than a predetermined level (step S32). The predetermined level is, for example, the same level as the predetermined level used for the level determination in step S8 of FIG. 3 of the first embodiment. When it is determined that the level of the sound collecting signal is less than a predetermined level (step S32: NO), the sound leakage determination unit 91 determines that the sound has not leaked to the outside of the vehicle 2, and proceeds to the process of step S12.

When it is determined that the level of the sound collecting signal is equal to or higher than a predetermined level (step S32: YES), the sound leakage determination unit 91 determines that the sound is leaking to the outside of the vehicle 2, and the comparison unit 91b of the sound leakage determination unit 91 determines. The time-series data of the sound collection signal of the sound collection data 102 is subjected to FFT (Fast Foyer Transfer) processing, and the sound collection signal for a predetermined time is decomposed into frequency components (step S33). Also. The comparison unit 91b performs FFT processing on the time-series data of the reproduced sound signal of the reproduced sound data 103, and decomposes the reproduced sound signal for a predetermined time into frequency components (step S34).

The comparison unit 91b calculates the difference between the frequency component of the sound collection signal (for example, the spectral intensity) and the frequency component of the reproduced sound signal for each frequency, and integrates the difference value of each frequency (step S35). The integration in step S35 may be performed for each predetermined frequency (for example, 100 Hz) in all frequency regions of the acquired sound collection signal and the reproduced sound signal, or in order to reduce the processing load, the sound collection signal and the sound collection signal may be integrated. It may be performed for each predetermined frequency in a part of the frequency band of all the frequency regions of the reproduced sound signal (for example, 300 to 3400 Hz in the telephone voice band).

FIG. 12 shows an example of the frequency spectra of the reproduced sound signal and the sound collecting signal. In FIG. 12, the horizontal axis is time and the vertical axis is frequency. FIG. 12A is an example of the frequency spectrum FS3 of the reproduced sound signal inside the vehicle 2, and is not affected by noise. FIG. 12B is a frequency spectrum FS4 of a sound collecting signal outside the vehicle 2, which is affected by noise.
FIG. 13 shows a comparative example of the frequency components of the reproduced sound signal and the sound collecting signal shown in FIG. In FIG. 13, the horizontal axis is the frequency and the vertical axis is the spectral intensity. In FIG. 13, the graph indicated by the reference numeral F1 is the frequency component of the reproduced sound signal, and the graph indicated by the reference numeral F2 is the frequency component of the sound collection signal. In step S35, for example, the integrated value of the difference between the two graphs F1 and F2 for each frequency is obtained.

FIG. 14 is an example of time-dependent changes in the level of the reproduced sound signal and the level of the sound collecting signal. In FIG. 14, the horizontal axis is time and the vertical axis is the sound signal level. FIG. 14A shows a sound collecting signal C1 outside the vehicle 2, and FIG. 14B shows a reproduced sound signal P1 inside the vehicle 2. The volume of the reproduced sound signal P1 is at an intermediate level.
FIG. 15 shows a comparative example of the frequency components of the reproduced sound signal P1 and the sound collecting signal C1 shown in FIG. In FIG. 15, the horizontal axis is frequency and the vertical axis is spectral intensity. In FIG. 15, the graph indicated by the reference numeral F3 is the frequency component of the reproduced sound signal P1, and the graph indicated by the reference numeral F4 is the frequency component of the sound collecting signal C1. In step S35, for example, the integrated value of the difference for each frequency between the two graphs F3 and F4 is obtained.

FIG. 16 is another example of the time variation of the level of the reproduced sound signal and the level of the sound collecting signal. In FIG. 16, the horizontal axis is time and the vertical axis is the sound signal level. FIG. 16A shows a sound collecting signal C2 outside the vehicle 2, and FIG. 16B shows a reproduced sound signal P2 inside the vehicle 2. The volume of the reproduced sound signal P2 is higher than the volume of the reproduced sound signal P1 shown in FIG. Comparing the level of the sound collecting signal C2 shown in FIG. 16A with the level of the sound collecting signal C1 shown in FIG. 14A, the sound collecting signal C2 shown in FIG. 16A is larger. As described above, when the volume of the reproduced sound is high, the volume of the sound leaking to the outside of the vehicle 2 is also high.

FIG. 17 shows a comparative example of the frequency components of the reproduced sound signal P2 and the sound collecting signal C2 shown in FIG. In FIG. 17, the horizontal axis is the frequency and the vertical axis is the spectral intensity. In FIG. 17, the graph indicated by the reference numeral F5 is the frequency component of the reproduced sound signal P2, and the graph indicated by the reference numeral F6 is the frequency component of the sound collecting signal C2. In step S35, for example, the integrated value of the difference for each frequency between the two graphs F5 and F6 is obtained.

Comparing the two graphs F3 and F4 shown in FIG. 15 with the two graphs F5 and F6 shown in FIG. 17, the difference between the two graphs F5 and F6 shown in FIG. 17 is smaller, and the difference for each frequency is smaller. The volume of the reproduced sound shown in FIG. 17 is lower when the volume is higher. That is, when the volume of the reproduced sound inside the vehicle 2 is high, the volume of the sound leaking to the outside of the vehicle 2 is large, and the louder the volume of the sound leaking to the outside is, the frequency component of the reproduced sound signal and the frequency of the sound collection signal. The difference from the components becomes smaller, and the degree of matching becomes higher. Therefore, the more the reproduced sound leaks to the outside of the vehicle 2, the smaller the integrated value of the difference for each frequency calculated in step S35.

When the integrated value of the difference is calculated in step S35 in the flowchart of FIG. 10, the comparison unit 91b determines whether or not the integrated value is equal to or less than a predetermined value (step S36). The predetermined value is a threshold value for determining whether or not the reproduced sound is leaking to the outside of the vehicle 2 (in particular, whether or not the sound collecting signal and the reproduced sound signal are similar). This predetermined value is set in advance and is stored in, for example, the memory 100. This predetermined value may be changed by the occupant.

When it is determined that the integrated value is equal to or less than the predetermined value (step S36: YES), the comparison unit 91b determines that the reproduced sound is leaking to the outside of the vehicle 2, and proceeds to the process of step S9. On the other hand, when it is determined that the integrated value is larger than the predetermined value (step S36: NO), the comparison unit 91b determines that the reproduced sound is not leaking to the outside of the vehicle 2, and proceeds to the process of step S12.

Next, with reference to the flowchart of FIG. 11, the operation when the comparison method in the comparison unit 91b is a method of comparing the voice recognition results will be described. In the operation description using FIG. 11, the same step number is assigned to the same process as in FIG. 10, and the description is omitted.

When it is determined in the determination in step S32 that the level of the sound collection signal is equal to or higher than a predetermined level (step S32: YES), the comparison unit 91b performs voice recognition processing on the time-series data of the sound collection signal of the sound collection data 102. The words included in the sound collection signal are acquired, and these words are converted into text (step S40). Further, the comparison unit 91b performs voice recognition processing on the time-series data of the reproduced sound signal of the reproduced sound data 103, acquires the words included in the reproduced sound signal, and converts the words into text (step S41).

FIG. 18 shows a comparative example of the voice recognition result of the reproduced sound signal and the sound collecting signal. In FIG. 18, the horizontal axis is time and the vertical axis is frequency. FIG. 18A is an example of the frequency spectrum FS5 of the reproduced sound signal inside the vehicle 2. FIG. 18B is an example of the frequency spectrum FS6 of the sound collecting signal outside the vehicle 2. From the frequency spectrum FS5 of the reproduced sound signal shown in FIG. 18 (A), the word "a" is recognized at time T10, the word "i" is recognized at time T11, and the word "i" is recognized at time T12 by voice recognition processing. "U" was recognized, the word "e" was recognized at time T13, and the word "o" was recognized at time T14. On the other hand, from the frequency spectrum FS6 of the sound collection signal shown in FIG. 18B, "A" is recognized at time T10, the word is not recognized at time T11, and the word is not recognized at time T12 by the voice recognition process. , The word "e" was recognized at time T13, and the word "o" was recognized at time T14. In the case of the example shown in FIG. 18, the degree of agreement between the words of the reproduced sound signal and the sound collecting signal is 60%. For example, if the degree of word matching is about 60%, it is judged that the content of the hand-free call conversation is unknown.

Returning to FIG. 11, the comparison unit 91b calculates the degree of coincidence between the voice recognition result (text data) acquired from the sound collection signal and the voice recognition result (text data) acquired from the sound collection signal (step S42). The comparison unit 91b determines whether or not the degree of agreement is equal to or greater than a predetermined degree (step S43). The predetermined degree is a threshold value for determining whether or not the reproduced sound is leaking to the outside of the vehicle 2 (in particular, whether or not the conversation content of the reproduced sound of the hands-free call can be heard). This predetermined degree is set in advance and is stored in, for example, the memory 100. The occupant may be able to change this predetermined degree.

When it is determined that the degree of coincidence is equal to or higher than the predetermined degree (step S43: YES), the comparison unit 91b determines that the reproduced sound is leaking to the outside of the vehicle 2, and proceeds to the process of step S9. On the other hand, when it is determined that the degree of matching is less than the predetermined degree (step S43: NO), the comparison unit 91b determines that the reproduced sound has not leaked to the outside of the vehicle 2, and proceeds to the process of step S12.

The comparison unit 91b determines whether the playback sound of the hands-free call is leaking to the outside of the vehicle 2 by the processing of one of the comparison methods of the process shown in the flowchart of FIG. 10 and the process shown in the flowchart of FIG. 11 described above. do. The comparison unit 91b performs each of the comparison methods of both the process shown in the flowchart of FIG. 10 and the process shown in the flowchart of FIG. 11 described above, and comprehensively determines the results obtained by the two comparison methods. Therefore, it may be configured to determine whether or not the reproduced sound of the hands-free call is leaking to the outside of the vehicle 2.

The privacy protection system 70 of the second embodiment has the same effect as the privacy protection system 10 of the first embodiment, and also has the following effects. According to the privacy protection system 70, a comparison unit 91b is provided, and when the level of the sound collection signal is equal to or higher than a predetermined level, the reproduced sound signal and the sound collecting signal are compared to correlate the reproduced sound signal with the sound collecting signal. Based on the nature, it is possible to accurately determine whether or not the reproduced sound of the hands-free call is leaking to the outside of the vehicle 2, and if it is determined that the reproduced sound is leaking to the outside, it is possible to execute a listening difficulty process. In particular, according to the privacy protection system 70, it is possible to accurately determine whether or not the conversation content due to the reproduced sound of the hands-free call may be heard by a person outside the vehicle 2. Further, according to the privacy protection system 70, since the comparison is performed using the reproduced sound signal during the hands-free call, even if the sound such as music is output from the audio device 25 during the hands-free call, it is hands-free. It is possible to accurately determine whether or not the reproduced sound of the call is leaking to the outside of the vehicle 2.

According to the privacy protection system 70, the reproduced sound signal and the sound collecting signal are frequency-converted, and the frequency component of the reproduced sound signal and the frequency component of the sound collecting signal are compared with each other to obtain the reproduced sound signal and the sound collecting signal. The correlation can be determined, and the accuracy of determining whether or not the reproduced sound of the hands-free call is leaking to the outside of the vehicle 2 can be improved.

According to the privacy protection system 70, the reproduced sound signal and the sound collecting signal are recognized by voice, and the reproduced sound signal and the sound collecting signal are compared with the voice recognition result of the reproduced sound signal and the voice recognition result of the sound collecting signal. It is possible to determine whether or not the reproduced sound of the hands-free call is leaking to the outside of the vehicle 2.

According to the privacy protection system 70, by performing masking processing based on the conditions of the vehicle speed and the current position, the reproduced sound is not leaked to the outside of the vehicle 2 in the comparison unit 91b (the conversation content of the reproduced sound is outside the vehicle 2). By not lowering the volume of the reproduced sound when it is determined (the possibility of being heard by a person is low), privacy can be ensured without lowering the volume of the hands-free call in the vehicle 2 as much as possible.

According to the privacy protection system 70, when only the sound such as music of the audio device 25 is output from the in-vehicle speaker 30, a louder volume than the privacy is a problem. Therefore, when the volume is loud, an alarm is displayed. By encouraging the occupants to lower the volume or the like, it is possible to suppress the degree of inconvenience to people outside the vehicle 2.

The above embodiment shows a specific example to which the present invention is applied, and the present invention is not limited thereto.

For example, in the above embodiment, it is applied to an automobile as a moving body, but it can also be applied to other moving bodies. For example, it can be applied to a motorcycle, and in the case of a motorcycle, a speaker is provided in a helmet worn by the driver of the motorcycle, and the reproduced sound of a hands-free call is output from this speaker. When it is determined that the reproduced sound reproduced by the speaker of the helmet is leaking to the outside during a hands-free call, the privacy protection system of the present invention makes it difficult for a person existing around the motorcycle to hear the reproduced sound. Has a function.

Also, for example, it can be applied to airplanes, private space is secured for each passenger in the first class of airplanes, a speaker is provided on the seat on which the passenger sits, and the playback sound of hands-free call is output from this speaker. Will be done. When the privacy protection system of the present invention determines that the reproduced sound reproduced by the speaker of the seat during a hands-free call leaks to the outside of the private space (inside the private space of another passenger), the surrounding other It has a function to make it difficult for other passengers in the private space to hear the reproduced sound.

Further, in the above embodiment, the masking sound output process and the reproduced sound volume reduction process are performed as the listening difficulty process, but the masking sound output process and the reproduced sound volume reduction process are performed as the listening difficulty process. It may be configured to perform processing of either one of them.

In the above embodiment, the display 34 is configured to display information that the playback sound of the hands-free call is leaking to the outside of the vehicles 1 and 2 and alarm information such as prompting the user to lower the volume by manual operation. The alarm information may be notified by, for example, the alarm information may be notified by the voice output from the in-vehicle speaker 30.

Further, in the above embodiment, in addition to the determination using the sound collecting signal, the determination using the vehicle speed and the current position of the vehicles 1 and 2 is performed, and the reproduced sound of the hands-free call is leaked to the outside of the vehicles 1 and 2. Although it was determined whether or not there was a possibility, whether or not the reproduced sound leaked to the outside of the vehicles 1 and 2 by the determination using the sound collecting signal without making such a determination using the vehicle speed and the current position. May be determined.

Further, in the first embodiment, the vehicle 1 determines whether or not to lower the volume of the reproduced sound only by determining the level of the sound collection signal, but the vehicle 1 of the first embodiment also collects the sound as in the second embodiment. In addition to determining the level of the sound signal, the sound collection signal and the reproduced sound signal may be compared (comparison of frequency components, comparison of voice recognition results) to determine whether or not to lower the volume of the reproduced sound. ..

Further, FIGS. 1 and 8 are schematic views showing the functional configurations of the privacy protection systems 10 and 70 classified according to the main processing contents in order to make the invention of the present application easy to understand. The configuration of 70 can be classified into more request elements according to the processing content. It can also be categorized so that one component performs more processing. Further, the processing of each component may be executed by one hardware or may be executed by a plurality of hardware. Further, the processing of each component may be realized by one program or may be realized by a plurality of programs.

Further, in the control units 40 and 80 of the privacy protection systems 10 and 70 of FIGS. 1 and 8, the control programs 61 and 101 executed by the CPUs 50 and 90 are downloaded from an external server or the like via, for example, a communication network. Then, it may be loaded on the memories 60 and 100 such as RAM and executed by the CPUs 50 and 90. Further, it may be directly loaded from an external server into memories 60 and 100 such as RAM via a communication network and executed by CPUs 50 and 90. Alternatively, the storage medium connected to the privacy protection systems 10 and 70 may be loaded onto the memories 60 and 100 such as RAM.

Further, the processing units of the flowcharts of FIGS. 3, 9, 10 and 11 are divided according to the main processing contents in order to facilitate understanding of the processing by the privacy protection systems 10 and 70. The invention of the present application is not limited by the method of dividing the processing unit and the name. The processing of the privacy protection systems 10 and 70 can be divided into more processing units according to the processing content. It is also possible to divide one processing unit so as to include more processing. Further, the processing order of the flowcharts of FIGS. 3, 9, 10 and 11 is not limited to the illustrated example as long as the same processing result can be obtained.

1 and 2 vehicles (moving bodies)
10, 70 Privacy protection system 20 Hands-free calling device 21 Vehicle speed sensor (speed acquisition unit)
22 Navigation device (current position acquisition unit)
22a Map database 23 Noise canceller 24 Microphone (sound collector)
25 Audio device 30 In-vehicle speaker 31, 33 amplifier 32 External speaker (sound output section)
34 Display 40, 80 Control unit 50, 90 CPU (processing unit)
51, 91 Sound leakage determination unit 51a, 91a Level determination unit 91b Comparison unit 52, 92 Masking control unit 53, 93 Volume control unit 54, 94 Alarm control unit 60, 100 Memory 61, 101 Control program 62, 102 Sound collection data 103 Playback sound data

Claims (9)

A privacy protection system that is mounted on a moving body and outputs a reproduced sound to a occupant of the moving body in a predetermined space around the occupant.
A sound collecting unit that collects sounds outside the predetermined space, and
When the level of the sound collected by the sound collecting unit is equal to or higher than a predetermined level, a processing unit that executes a listening difficulty process that makes it difficult to hear the reproduced sound outside the predetermined space, and a processing unit.
A privacy protection system characterized by being equipped with. When the level of the sound collected by the sound collecting unit is equal to or higher than the predetermined level, the processing unit is difficult to hear based on the comparison result between the reproduced sound and the sound collected by the sound collecting unit. The privacy protection system according to claim 1, wherein the conversion process is executed. The processing unit frequency-converts the reproduced sound and the sound collected by the sound collecting unit, and compares the frequency component of the reproduced sound with the frequency component of the sound collected by the sound collecting unit. 2. The privacy protection system according to claim 2. The processing unit recognizes the reproduced sound and the sound collected by the sound collecting unit, respectively, and compares the voice recognition result of the reproduced sound with the voice recognition result of the sound collected by the sound collecting unit. The privacy protection system according to claim 2 or 3, characterized in that. A sound output unit that outputs sound to the outside of the predetermined space is provided.
The privacy according to any one of claims 1 to 4, wherein the listening difficulty processing outputs a masking sound that masks the reproduced sound leaking to the outside of the predetermined space by the sound output unit. Protection system. The privacy protection system according to any one of claims 1 to 5, wherein the listening difficulty processing reduces the volume of the reproduced sound. A speed acquisition unit for acquiring the speed of the moving body is provided.
The privacy protection system according to any one of claims 1 to 6, wherein the processing unit executes the listening difficulty processing when the speed acquired by the speed acquisition unit is less than a predetermined speed. .. A current position acquisition unit for acquiring the current position of the moving body is provided.
Any one of claims 1 to 7, wherein the processing unit executes the listening difficulty processing when the current position of the moving body acquired by the current position acquisition unit is a predetermined position. The privacy protection system described in the section. The privacy protection system according to any one of claims 1 to 8, wherein the reproduced sound is a received sound of a hands-free call.

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