Sound processing system and sound processing method

Abstract

Provided are a sound processing system and method for performing sound processing using both analog and digital sound signals in a vehicle equipped with a mixture of analog and digital microphones. The sound processing system includes: one or more analog microphones disposed within the vehicle interior and outputting a first analog sound signal; one or more digital microphones disposed within the vehicle interior and outputting a digital sound signal; a digital-to-analog converter that converts the digital sound signal into a second analog sound signal; and a sound signal processor including a delay processor that delays the first analog sound signal based on at least a delay time when the digital-to-analog converter converts a digital sound signal received at the same time as the first analog sound signal into the second analog sound signal, and outputs the signal as a third analog sound signal. The sound signal processor performs sound signal processing based on the second and third analog sound signals.

Description

Technical Field

[0001] The present invention relates to a sound processing system and a sound processing method. Background Art

[0002] In the past, a technology related to the following vehicle device has been disclosed, which receives an operation corresponding to an input voice command (for example, refer to Japanese Patent Application Publication No. 2012-213132). In the previous technology, the voice command is recognized by a voice recognition mechanism based on the speech of the user output by the microphone. In the past, there were analog microphones that output analog sound signals and digital microphones that output digital sound signals. In recent years, the introduction of digital microphones as a sound input mechanism in systems installed in vehicles has been continuously studied. However, it is sometimes difficult to convert all previous analog microphones into digital microphones, for example, due to cost considerations. Therefore, in the vehicle system, it is considered to have analog microphones and digital microphones coexist. However, in the previous technology, a structure that can replace analog microphones with digital microphones is recorded, but the situation of having analog microphones and digital microphones coexist is not considered.

[0003] For example, Japanese Patent No. 5242488 discloses a technology related to a wireless microphone system that uses a mixture of analog and digital microphones. Japanese Patent No. 5242488 describes a system that includes an analog receiver for analog microphones and a digital receiver for digital microphones, and transmits audio signals from each microphone via a hybrid distributor, thereby enabling the coaxial cable between the microphones and receivers to be shared.

[0004] However, the technology described in Japanese Patent No. 5242488 relates to the transmission of sound signals in a system that uses a mixture of analog and digital microphones, and does not relate to a system that uses both analog and digital sound signals for sound processing. Thus, prior art has not disclosed a technology for implementing a sound processing system that uses both analog and digital sound signals for sound processing in a vehicle that uses a mixture of analog and digital microphones.

[0005] The present invention has been made based on the above-mentioned problem recognition, and its object is to provide a sound processing system and a sound processing method that can perform sound processing using both analog sound signals and digital sound signals in a vehicle having a mixture of analog microphones and digital microphones. Summary of the Invention

[0006] Technical solutions to technical problems

[0007] The sound processing system and the sound processing method of the present invention adopt the following configuration.

[0008] (1): A sound processing system according to one embodiment of the present invention comprises: one or more analog microphones, which are arranged in a vehicle interior and output a first analog sound signal; one or more digital microphones, which are arranged in the vehicle interior and output a digital sound signal; a digital-to-analog conversion unit, which converts the digital sound signal into a second analog sound signal; and a sound signal processing unit, which comprises a delay processing unit, which delays at least the first analog sound signal based on a delay time when the digital-to-analog conversion unit converts the digital sound signal received at the same time as the first analog sound signal into the second analog sound signal and outputs it as a third analog sound signal, and the sound signal processing unit performs sound signal processing based on the second analog sound signal and the third analog sound signal.

[0009] (2): In the above-mentioned scheme (1), the sound signal processing unit performs the sound signal processing based on the second analog sound signal and the third analog sound signal to cause the sound device arranged in the vehicle interior to emit a sound output signal for eliminating noise in the vehicle interior.

[0010] (3): In the above-mentioned scheme (1) or (2), the sound signal processing unit further includes a sound correction unit, which uses a correction value obtained based on information on the configuration positions of the analog microphone and the digital microphone in the vehicle interior, or information on the distance between the configuration positions in the vehicle interior, to correct the first analog sound signal or the second analog sound signal. When an abnormality occurs in the analog microphone, the sound correction unit outputs a simulated sound signal obtained by correcting the second analog sound signal with the correction value as the third analog sound signal.

[0011] (4): In any one of the above schemes (1) to (3), the sound signal processing unit further includes a sound correction unit, which corrects the first analog sound signal or the second analog sound signal with a correction value obtained based on information on the configuration positions of the analog microphone and the digital microphone in the vehicle interior, or information on the distance between the configuration positions in the vehicle interior. When an abnormality occurs in the digital microphone, the sound correction unit outputs the simulated sound signal obtained by correcting the first analog sound signal with the correction value as the second analog sound signal.

[0012] (5): In the above-mentioned scheme (3) or (4), the sound signal processing unit forms a bidirectional direction pointing to the driver's seat and the front passenger seat in the vehicle cabin by the analog microphone and the digital microphone. When an abnormality occurs in one of the analog microphone and the digital microphone, the sound signal processing unit switches to a unidirectional direction pointing the other of the analog microphone and the digital microphone that is not abnormal to the driver's seat.

[0013] (6): In addition, a sound processing method of one embodiment of the present invention causes a computer to perform the following processing: at least a first analog sound signal output by one or more analog microphones arranged in a vehicle interior is delayed and used as a third analog sound signal based on a delay time when a digital-to-analog conversion unit converts a digital sound signal output by one or more digital microphones arranged in the vehicle interior, which is received at the same time as the first analog sound signal, into a second analog sound signal; and sound signal processing is performed based on the second analog sound signal and the third analog sound signal.

[0014] Effects of the Invention

[0015] According to the above-mentioned aspects (1) to (6), in a vehicle having a mixture of analog microphones and digital microphones, it is possible to perform audio processing using each of the analog audio signal and the digital audio signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the sound processing system according to the embodiment.

[0017] Figure 2 This is a diagram showing an example of a path of an audio signal.

[0018] Figure 3 This is a diagram (part 1) showing another example of the path of the audio signal.

[0019] Figure 4 This is a diagram (part 2) showing another example of the path of the audio signal.

[0020] Figure 5 This is a diagram showing an example of the arrangement of components included in a sound processing system in a vehicle.

[0021] Figure 6 This is a diagram illustrating an example of directivity formed in a sound processing system. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of a speech processing system and a speech processing method according to the present invention will be described with reference to the accompanying drawings.

[0023] [Structure of the sound processing system]

[0024] Figure 1 This is a schematic diagram of the sound processing system according to an embodiment. The vehicle equipped with the sound processing system is, for example, a four-wheeled vehicle, driven by an internal combustion engine such as a diesel engine or a gasoline engine, an electric motor, or a combination thereof. The electric motor operates using power generated by a generator connected to the internal combustion engine, or power discharged from a secondary battery or fuel cell.

[0025] exist Figure 1 In FIG. 1 , a speaker 50 is shown as a component related to the sound processing system 1 among the components included in a vehicle equipped with the sound processing system 1 (hereinafter referred to as "vehicle M"). The speaker 50 emits the sound signal output by the sound processing device 100 into the interior of the vehicle M. For example, the speaker 50 can also serve as a speaker configured to play music into the interior of the vehicle, or it can be configured within the interior of the vehicle as a dedicated device for the sound processing system 1. The speaker 50 is an example of an "acoustic device" in the technical solution.

[0026] The speech processing system 1 includes, for example, an analog microphone unit 10 , a digital microphone unit 20 , a digital-to-analog converter (DAC) 30 , a speech processing device 100 , and a microphone information database (DB) 40 .

[0027] The analog microphone unit 10 includes, for example, one or more microphone bodies 12 arranged at different positions in the vehicle interior. The microphone body 12 receives ambient sounds at the position arranged in the vehicle interior. The sounds received by the microphone body 12 include not only the sounds spoken by the occupants of the vehicle M, but also the noise in the vehicle interior (for example, music played in the vehicle interior, noise flowing from the outside of the vehicle into the vehicle interior, etc.). The analog microphone unit 10 outputs analog sound signals corresponding to the sounds received by each microphone body 12 to the sound processing device 100. The analog microphone unit 10 or the microphone body 12 is an example of an "analog microphone" in the technical solution, and the analog sound signal output by the analog microphone unit 10 to the sound processing device 100 is an example of a "first analog sound signal" in the technical solution.

[0028] The digital microphone unit 20 includes, for example, one or more microphone bodies 22 arranged at different positions in the vehicle interior, and an analog-to-digital converter (ADC) 24. The microphone body 22 receives ambient sound at a position arranged in the vehicle interior. The microphone body 22 may be the same device as the microphone body 12 included in the analog microphone unit 10. The sound received by the microphone body 22 includes not only the voices spoken by the occupants of the vehicle M, but also the noise in the vehicle interior. The ADC 24 converts the analog sound signal received and output by the corresponding microphone body 22 into a digital sound signal. The digital microphone unit 20 outputs the digital sound signal received by each microphone body 22 and converted by the ADC 24 to the DAC 30. The structure of the microphone body 22 and the ADC 24, or the digital microphone unit 20, is an example of a "digital microphone" in the technical solution.

[0029] DAC 30 converts the digital audio signal output by digital microphone unit 20 back into an analog audio signal. Specifically, DAC 30 returns the digital audio signal to the analog audio signal received by microphone body 22. DAC 30 outputs the converted analog audio signal to audio processing device 100. The analog audio signal output by DAC 30 to audio processing device 100 is an example of the "second analog audio signal" in the technical solution.

[0030] The sound processing device 100 performs sound signal processing based on the analog sound signal output by the analog microphone unit 10 (hereinafter referred to as the "analog microphone sound signal") and the analog sound signal output by the DAC 30 (hereinafter referred to as the "digital microphone sound signal"). The sound processing device 100 includes, for example, a microphone recognition unit 111, a microphone recognition unit 112, a fault determination unit 121, a fault determination unit 122, a sound processing unit 140, and a signal processing unit 160. The sound processing unit 140 includes, for example, a delay processing unit 142 and a sound correction unit 144. The signal processing unit 160 includes, for example, a noise cancellation processing unit 162. These components can be implemented by hardware (including circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a GPU (Graphics Processing Unit), or can be implemented by a dedicated LSI. Some or all of these components can be implemented, for example, by executing a program (software) on a hardware processor such as a CPU (Central Processing Unit), or by the collaboration of software and hardware. The program can be pre-stored in a storage device (a storage device with a non-temporary storage medium) such as an HDD (Hard Disk Drive) or a flash memory of the vehicle M, or can be stored in a removable storage medium (a non-temporary storage medium) such as a DVD or CD-ROM, and installed in the HDD or flash memory of the vehicle M by assembling the storage medium on a drive device of the vehicle M. The sound processing device 100 is an example of a "sound signal processing unit" in the technical solution. The analog microphone sound signal is an example of a "first analog sound signal" in the technical solution, and the digital microphone sound signal is an example of a "second analog sound signal" in the technical solution.

[0031] The microphone recognition unit 111 recognizes the microphone main body 12 disposed at each position in the vehicle interior, and outputs a simulated microphone audio signal collected and output by each microphone main body 12 to the audio processing unit 140 and the failure determination unit 121 .

[0032] Microphone recognition unit 112 identifies microphone bodies 22 located at various locations within the vehicle cabin based on the digital microphone audio signals output by DAC 30, and outputs digital microphone audio signals corresponding to the analog audio signals picked up and output by each microphone body 22 to audio processing unit 140 and fault determination unit 121. Microphone recognition unit 112 may be the same device as microphone recognition unit 111. Microphone recognition unit 111 and microphone recognition unit 112 may also constitute a single component.

[0033] The fault determination unit 121 determines whether an abnormality has occurred in each microphone body 12 based on the simulated microphone sound signal output by the microphone recognition unit 111. If the fault determination unit 121 determines that an abnormality has occurred in any microphone body 12, it outputs a notification signal to the sound processing unit 140 to notify the microphone body 12 determined to have an abnormality.

[0034] Fault determination unit 122 determines whether an abnormality has occurred in each microphone body 22 (including ADC 24) based on the digital microphone sound signal output by microphone identification unit 112. If fault determination unit 122 determines that an abnormality has occurred in any microphone body 22, it outputs a notification signal to audio processing unit 140 to notify the microphone body 22 that the abnormality has occurred. Fault determination unit 122 may be a device similar to fault determination unit 121. Fault determination unit 121 and fault determination unit 122 may also constitute a single component.

[0035] Delay processing unit 142 delays the input sound signal by a predetermined time based on delay time information (described later) stored in microphone information DB 40. More specifically, delay processing unit 142 delays the analog microphone sound signal output by microphone identification unit 111 by the delay time of the digital microphone sound signal. The delay time of the digital microphone sound signal occurs because the analog microphone sound signal is transmitted through a path that is not connected to other components, whereas the digital microphone sound signal is transmitted through an ADC 24 and a DAC 30. For example, even if microphone body 12 and microphone body 22 receive sound at the same time, the analog microphone sound signal is transmitted directly. In contrast, the digital microphone sound signal undergoes analog-to-digital conversion by ADC 24 and digital-to-analog conversion by DAC 30 before being transmitted. Therefore, the signal is delayed by at least the conversion time required by DAC 30 before being input to sound processing device 100. Therefore, delay processing unit 142 delays the analog microphone sound signal to eliminate the time difference in transmission between the analog microphone sound signal and the digital microphone sound signal based on the sound received at the same time. Delay processing unit 142 outputs the delayed analog microphone sound signal (hereinafter referred to as the "delayed sound signal") to signal processing unit 160. The delayed sound signal generated by delay processing unit 142 after delaying the analog microphone sound signal is an example of the "third analog sound signal" in the technical solution.

[0036] The sound modification unit 144 modifies the input sound signal based on the correction value information (described later) stored in the microphone information DB 40. More specifically, when an analog microphone sound signal is input, the sound modification unit 144 modifies the input analog microphone sound signal to generate a simulated sound signal that mimics a digital microphone sound signal. On the other hand, when a digital microphone sound signal is input, the sound modification unit 144 modifies the input digital microphone sound signal to generate a simulated sound signal that mimics the analog microphone sound signal.

[0037] The noise cancellation processing unit 162 performs sound signal processing based on the input sound signal, for example, to cancel noise within the vehicle interior, such as noise flowing from the exterior of the vehicle into the vehicle interior. More specifically, the noise cancellation processing unit 162 performs so-called active noise control processing based on the delayed sound signal and digital microphone sound signal input from the sound processing unit 140 (including the case where either of these sound signals is a simulated sound signal). In this active noise control processing, a sound signal (hereinafter referred to as a "noise cancellation sound signal") having a phase opposite to that of the noise within the vehicle interior contained in each sound signal is generated. The noise cancellation processing unit 162 causes the speaker 50 to emit the generated noise cancellation sound signal. As a result, the noise within the vehicle interior is canceled by the noise cancellation sound signal emitted by the speaker 50. The noise cancellation sound signal is an example of a "sound output signal" in the technical solution.

[0038] The microphone information DB 40 stores various information used in the processing of the sound processing device 100. For example, the microphone information DB 40 stores delay information related to the delay time used by the delay processing unit 142 to delay the analog microphone sound signal, that is, the time difference in transmission between the analog microphone sound signal and the digital microphone sound signal. This time difference in transmission between the analog microphone sound signal and the digital microphone sound signal includes not only the conversion time performed by the aforementioned ADC 24 and DAC 30, but also includes delay time within the vehicle interior, i.e., the acoustic space, due to factors such as the size and shape of the vehicle interior, the locations of the microphone bodies 12 and 22, and the location of the speaker 50 (hereinafter referred to as "acoustic delay time"). The acoustic delay time can be determined in advance for each microphone body through, for example, simulations using design data (so-called CAD data) of the vehicle M, measurements of actual sounds emitted in the actual vehicle M, and calculations based on the locations of the microphone bodies 12 and 22 within the vehicle interior and the distance between them. Furthermore, the time difference in transmission between the analog microphone audio signal and the digital microphone audio signal includes not only the conversion time performed by the aforementioned ADC 24 and DAC 30, but also delay time (hereinafter referred to as "system delay time") caused by the characteristics of the wiring harness (cable) that transmits the analog microphone audio signal and the digital microphone audio signal to the audio processing device 100, the processing of the wiring harness, and the time required to process each audio signal. The system delay time can be uniquely determined in advance for each microphone based on, for example, the connection relationship between the various components of the audio processing system 1 and the processing time of each component, and other factors related to the structure and specifications of the audio processing system 1. The microphone information DB 40 stores information on the previously determined acoustic delay time and system delay time. The microphone information DB 40 can store the acoustic delay time and system delay time separately, or it can store the total delay time of the acoustic delay time and system delay time. The delay time information stored in the microphone information DB 40 can also be stored in, for example, the storage unit of the audio processing unit 140 or the delay processing unit 142.

[0039] The microphone information DB40 stores, for example, correction value information related to correction values ​​used by the sound modification unit 144 to generate simulated signals simulating analog microphone audio signals and digital microphone audio signals. These correction values ​​include, for example, correction values ​​for correcting (harmonicizing) differences in level, frequency characteristics, and phase characteristics between the analog microphone audio signals and digital microphone audio signals. These correction values ​​can be determined in advance for each microphone based on methods and information used to determine acoustic delay time and system delay time. The correction value information stored in the microphone information DB40 can also be stored in, for example, a storage unit included in the sound processing unit 140 or the sound modification unit 144.

[0040] According to such a structure, the sound processing device 100 causes the speaker 50 to emit a noise cancellation sound signal for canceling the noise in the vehicle interior at the position where each microphone body is arranged based on the sound signal obtained based on the sound received by the microphone body 12 and the microphone body 22 arranged at each position in the vehicle interior.

[0041] [Sound signal used in sound signal processing by the sound processing system]

[0042] Here, the audio signal used by the noise cancellation processing unit 162 when generating the noise cancellation audio signal according to the states of the microphone body 12 and the microphone body 22 will be described. Figures 2 to 4 This is a diagram showing an example of the path of a sound signal. Figures 2 to 4 , which includes related components until the analog microphone sound signal from the analog microphone unit 10 and the digital microphone sound signal from the digital microphone unit 20 are input to the noise cancellation processing unit 162. Figure 2 , the paths of the respective audio signals in the normal operating state (a state where no abnormality occurs in each of the microphone body 12 and the microphone body 22) in the audio processing system 1 are shown. Figure 3 , the paths of the respective audio signals when it is determined that an abnormality has occurred in the microphone body 12 in the audio processing system 1 are shown. Figure 4 , the paths of the respective audio signals when it is determined that an abnormality has occurred in the microphone body 22 (including the ADC 24 ) in the audio processing system 1 are shown.

[0043] First, refer to Figure 2The paths of the various sound signals in the normal operating state are explained below. When there is no abnormality in each of the microphone body 12 and the microphone body 22, the sound processing unit 140 outputs the digital microphone sound signal input from the digital microphone unit 20 via the microphone identification unit 112 directly to the signal processing unit 160. On the other hand, the sound processing unit 140 delays the analog microphone sound signal input from the analog microphone unit 10 via the microphone identification unit 111 by the delay time of the digital microphone sound signal by the delay processing unit 142. Furthermore, the sound processing unit 140 outputs the delayed sound signal after the delay processing unit 142 delays it to the signal processing unit 160. Thus, the noise cancellation processing unit 162 included in the signal processing unit 160 generates a noise cancellation sound signal based on the digital microphone sound signal output by the sound processing unit 140 and the delayed sound signal obtained based on the analog microphone sound signal.

[0044] In this manner, the sound processing device 100 cancels the time difference between the delayed sound signal based on the analog microphone sound signal and the digital microphone sound signal, which are sounds received at the same time, and outputs the respective sound signals to the noise cancellation processing unit 162. This allows the noise cancellation processing unit 162 to generate a noise cancellation sound signal with higher accuracy for canceling noise in the vehicle cabin.

[0045] Next, refer to Figure 3 The following describes the paths of various audio signals when an abnormality is determined in microphone body 12. When fault determination unit 121 determines that an abnormality has occurred in microphone body 12 based on the analog microphone audio signal input from analog microphone section 10 via microphone identification unit 111, fault determination unit 121 notifies audio processing unit 140 of the abnormality. In this case, audio processing unit 140, as in normal operation, directly outputs the digital microphone audio signal input from digital microphone section 20 via microphone identification unit 112 to signal processing unit 160. On the other hand, audio processing unit 140 does not output the analog microphone audio signal input from analog microphone section 10 via microphone identification unit 111 to signal processing unit 160. Instead, audio processing unit 140 generates a simulated audio signal that simulates the analog microphone audio signal based on the digital microphone audio signal output to signal processing unit 160 using audio correction unit 144. Furthermore, the sound processing unit 140 outputs the simulated sound signal generated by the sound correction unit 144 to the signal processing unit 160 as a delayed sound signal obtained based on the analog microphone sound signal. Consequently, the noise cancellation processing unit 162 included in the signal processing unit 160 generates a noise cancellation sound signal based on the digital microphone sound signal output by the sound processing unit 140 and the delayed sound signal (actually, the simulated sound signal) obtained based on the analog microphone sound signal, as in the normal operating state.

[0046] In this manner, when the sound processing device 100 determines that an abnormality has occurred in the microphone body 12, it outputs a simulated sound signal obtained by simulating the analog microphone sound signal based on the digital microphone sound signal, as well as the digital microphone sound signal, to the noise cancellation processing unit 162. Thus, the noise cancellation processing unit 162 can generate a noise cancellation sound signal for canceling noise in the vehicle cabin even when an abnormality has occurred in the microphone body 12.

[0047] In this case, audio processing unit 140 does not delay the simulated audio signal using delay processing unit 142. This is because the digital microphone audio signal used to generate the simulated audio signal already includes a delay, meaning there is no time difference between the digital microphone audio signal and the simulated audio signal. However, if audio modification unit 144 requires time to generate the simulated audio signal, audio processing unit 140 may instead have delay processing unit 142 delay the digital microphone audio signal by the amount of processing time required by audio modification unit 144 before outputting it to signal processing unit 160.

[0048] Next, refer to Figure 4The following describes the paths of various audio signals when an abnormality is determined in microphone body 22. When fault determination unit 122 determines that an abnormality has occurred in microphone body 22 based on the digital microphone audio signal input from digital microphone unit 20 via microphone identification unit 112, fault determination unit 122 notifies audio processing unit 140 of the abnormality. In this case, audio processing unit 140, as in normal operation, uses delay processing unit 142 to delay the analog microphone audio signal input from analog microphone unit 10 via microphone identification unit 111, resulting in a delayed audio signal that is output to signal processing unit 160. On the other hand, audio processing unit 140 does not output the digital microphone audio signal input from digital microphone unit 20 via microphone identification unit 112 to signal processing unit 160. Instead, audio processing unit 140 uses audio correction unit 144 to generate a simulated audio signal that mimics the digital microphone audio signal based on the analog microphone audio signal input via microphone identification unit 111. Furthermore, the sound processing unit 140 uses the delay processing unit 142 to delay the simulated sound signal generated by the sound correction unit 144 by the delay time of the original digital microphone sound signal. Furthermore, the sound processing unit 140 outputs the delayed sound signal obtained by the delay processing unit 142 as a digital microphone sound signal to the signal processing unit 160. Consequently, the noise cancellation processing unit 162 included in the signal processing unit 160 generates a noise cancellation sound signal based on the digital microphone sound signal output by the sound processing unit 140 (actually, the delayed sound signal obtained by delaying the simulated sound signal) and the delayed sound signal obtained based on the simulated microphone sound signal, as in the normal operating state.

[0049] In this manner, when the sound processing device 100 determines that an abnormality has occurred in the microphone body 22, it outputs a delayed sound signal obtained by simulating a digital microphone sound signal based on the analog microphone sound signal and further delaying it, as well as a delayed sound signal obtained by delaying the analog microphone sound signal, to the noise cancellation processing unit 162. This allows the noise cancellation processing unit 162 to generate a noise cancellation sound signal for canceling noise within the vehicle cabin even when an abnormality has occurred in the microphone body 22.

[0050] At this point, there's no time difference between the simulated sound signal generated by sound modification unit 144 and the analog microphone sound signal that serves as the source of the simulated sound signal. Therefore, sound processing unit 140 considers it unnecessary to have delay unit 142 delay the analog microphone sound signal. However, noise cancellation unit 162 performs sound signal processing to generate the noise cancellation sound signal at a timing that is coordinated with the digital microphone sound signal. Therefore, sound processing unit 140 outputs the delayed sound signal, which is the result of delaying the analog microphone sound signal by delay unit 142, to signal processing unit 160 to avoid changing the timing of sound signal processing by noise cancellation unit 162. To accommodate this, sound processing unit 140 also delays the simulated sound signal generated by sound modification unit 144 by delay unit 142 and then outputs it to signal processing unit 160. The above description describes a case where delay unit 142 delays the simulated sound signal to the original digital microphone sound signal. However, if the sound correction unit 144 takes time to generate the simulated sound signal, the sound processing unit 140 may also use the delay processing unit 142 to delay the simulated sound signal by an amount of time obtained by subtracting the processing time required by the sound correction unit 144 from the delay time in the original digital microphone sound signal, that is, reduce the delay amount, and output it to the signal processing unit 160.

[0051] In this way, even if the sound processing device 100 determines that any microphone unit has an abnormality, the noise cancellation processing unit 162 can generate a noise-canceled sound signal using the same sound signal processing as in normal operation by mimicking the sound signal originally output by the abnormal microphone unit in the sound processing unit 140. In other words, even if the sound processing device 100 determines that any microphone unit has an abnormality, there is no need to change the sound signal processing in the noise cancellation processing unit 162. Furthermore, in the sound processing device 100, the delay processing unit 142 and the sound correction unit 144 each generate a corresponding sound signal based on the information (delay time information and correction value information) stored in the microphone information DB 40. Therefore, for example, even if the sound processing system 1 is installed in a different vehicle or the arrangement of the microphone units 12 and 22 within the vehicle M is changed, the delay time information and correction value information stored in the microphone information DB 40 can be modified to match the connection relationship between the respective vehicles and components, without having to modify the components of the sound processing system 1. In other words, the sound processing system 1 can cope with various vehicles with the same configuration.

[0052] [Configuration Example of Components of a Sound Processing System]

[0053] Here, an example of the arrangement of the microphone main bodies in the cabin of the vehicle M will be described. Figure 51 is a diagram showing an example of the arrangement of components included in the sound processing system 1 in the vehicle M. Figure 5 , an example of a case where a microphone body 12 is disposed on each of the driver's seat DS and the passenger seat AS of the vehicle M, and two microphone bodies 22 are disposed on the rear seat BS. More specifically, Figure 5 In the example shown, the microphone body 12-1 is arranged below the driver's seat DS, the microphone body 12-2 is arranged below the passenger seat AS, the microphone body 22-1 is arranged below the left rear seat BS1, and the microphone body 22-2 is arranged below the right rear seat BS2. Figure 5 In the example shown, the DAC 30 and the sound processing device 100 are placed inside the dashboard or the instrument panel, and the speaker 50-1 is placed in the center console near the center in the vehicle width direction (Y direction in the figure) of the vehicle M, or on the upper part of the dashboard. Figure 5 In the example shown, the speaker 50-2 is arranged, for example, around the front pillar (A pillar) on the front side of the driver's seat DS, the speaker 50-3 is arranged, for example, around the front pillar on the front side of the passenger seat AS, the speaker 50-4 is arranged around the rear pillar (C pillar) on the rear side of the left rear seat BS1, and the speaker 50-5 is arranged around the rear pillar on the rear side of the right rear seat BS2. Figure 5 In the example shown, each component is connected by a corresponding wiring harness. More specifically, each microphone body 12 is connected to the DAC 30 by a wiring harness for digital signals, and the voice processing device 100 is connected to each microphone body 12, DAC 30, and each speaker 50 by a wiring harness for analog signals.

[0054] In such Figure 5 When microphone bodies 12 and 22 are arranged as in the example shown, sound processing device 100 can generate noise cancellation audio signals corresponding to the positions where the respective microphone bodies are arranged based on the respective analog microphone audio signals and digital microphone audio signals. Furthermore, sound processing device 100 outputs the corresponding noise cancellation audio signals to speaker 50 at each position, causing the speaker 50 to emit sound, thereby canceling the noise within the vehicle cabin at that position.

[0055] The arrangement of the microphone body 12 and the microphone body 22 in the vehicle M is not limited to Figure 5 For example, you can also Figure 5 In the example shown, part or all of the microphone body 12 is replaced with the microphone body 22, and part or all of the microphone body 22 is replaced with the microphone body 12. The arrangement of the speaker 50 in the vehicle M is not limited to Figure 5 An example configuration is shown.

[0056] [Microphone directivity in sound processing systems]

[0057] In addition, when there is only one microphone body 12 or one microphone body 22, the one microphone body does not have directivity and receives surrounding sounds in a non-directional manner. Figure 5 When multiple microphone bodies 12 and 22 are arranged as in the example shown, for example, microphone body 12-1 and microphone body 12-2, respectively, arranged at the driver's seat DS and the front passenger seat AS, which are arranged in the vehicle width direction (Y direction in the figure) of the vehicle M, can mutually form a bidirectional pattern that provides directionality to the received surrounding sound. Therefore, if the sound processing system 1 determines that any microphone body has an abnormality, a microphone body that is not abnormal can form a unidirectional pattern that provides directionality to, for example, the driver's seat DS.

[0058] Figure 6 1 is a diagram illustrating an example of directivity formed in the sound processing system 1. Figure 6 , an example of directivity formed by the microphone body 12-1 and the microphone body 12-2 on the driver's seat DS side and the passenger seat AS side is shown. Figure 6 In the diagram, 0° is the driver's seat DS side, and 180° is the front passenger seat AS side. Figure 6 In (a), an example of omnidirectional microphone formed by a microphone body 12 is shown. Figure 6 In (b), an example of bidirectionality formed by two microphone bodies 12 is shown. Figure 6 (c) shows an example of unidirectional pattern formed by the microphone main body 12 that is not abnormal when it is determined that one microphone main body 12 has an abnormality.

[0059] When no abnormality occurs in any microphone body 12, the sound processing device 100 Figure 6 As shown in (b), bidirectionality is formed to generate a noise cancellation sound signal. Thus, in the sound processing system 1, appropriate noise cancellation sound signals can be generated on the driver's seat DS side and the front passenger seat AS side respectively, and the speaker 50 can emit sound. On the other hand, when the sound processing device 100 determines that an abnormality has occurred in one microphone body 12, it switches to forming a unidirectionality on the driver's seat DS side by the microphone body 12 that has not occurred an abnormality, and generates a noise cancellation sound signal. Thus, in the sound processing system 1, appropriate noise cancellation sound signals can be generated at least on the driver's seat DS side and the speaker 50 can emit sound. The switching of directivity can also be performed by, for example, the microphone recognition unit 111, the microphone recognition unit 112, or by other components not shown in the figure.

[0060] exist Figure 5 In the example shown, for example, the two microphone bodies 22, namely the microphone body 22-1 and the microphone body 22-2, arranged at respective positions of the left rear seat BS1 and the right rear seat BS2 arranged in the vehicle width direction (Y direction in the figure), can also form bidirectional directivity with each other. Figure 5 In the example shown, for example, microphone bodies 12-1 and 22-1, positioned at respective positions on the driver's seat DS and left rear seat BS1, aligned along the vehicle's length (the X direction in the figure), and microphone bodies 12-2 and 22-2, positioned at respective positions on the passenger seat AS and right rear seat BS2, can similarly achieve bidirectional directivity. Consequently, the sound processing device 100 can similarly switch to unidirectional directivity on the driver's seat DS side using the unaffected microphone body, generating an appropriate noise cancellation sound signal at least on the driver's seat DS side. In particular, in situations where one microphone body is 12 and the other is 22, such as when microphone body 22 is positioned on the driver's seat DS and microphone body 12 is positioned on the passenger seat AS, it is considered effective to switch the unaffected microphone body to unidirectional directivity to generate a noise cancellation sound signal, given that it is unlikely that both microphone bodies 12 and 22 will experience a malfunction at the same time.

[0061] In the above description, the case where the sound processing device 100 switches to a unidirectional direction toward the driver's seat DS when it is determined that an abnormality has occurred in any microphone body is described. However, in the vehicle M, there may not always be passengers in the front passenger seat AS or the rear seat BS. That is, a case where only the driver is riding in the vehicle M is also considered. When this case is taken into consideration, the sound processing device 100 may not switch the directivity of the microphone body to a unidirectional direction when it is determined that an abnormality has occurred in any microphone body, but may switch the directivity of the microphone body according to the situation where there are passengers riding in the vehicle M. That is, even when there is no abnormality in any microphone body, the directivity of the microphone body may be switched when only the driver is riding in the vehicle M so as to generate an appropriate noise cancellation sound signal on the driver's seat DS side. In this case, the presence of passengers in vehicle M can be determined, for example, by using information (seating information) output by a seating sensor (not shown), which utilizes a pressure sensor provided at the bottom of each seat, a tension sensor installed on a seat belt, etc., or by performing image processing (passenger identification processing) on ​​an image of the interior captured by an interior camera (not shown) photographing the interior of the vehicle.

[0062] According to this structure and control method, in the sound processing system 1, the sound processing device 100 generates noise cancellation audio signals for canceling noise within the vehicle interior at the respective locations where the microphone bodies 12 and 22 are located, based on audio signals obtained based on sound received by the microphone bodies 12 and 22 located at respective locations within the vehicle interior. Furthermore, in the sound processing system 1, the sound processing device 100 generates the noise cancellation audio signals by eliminating the time difference between the delayed audio signal and the digital microphone audio signal obtained based on the analog microphone audio signal received at the same time. This allows the generated noise cancellation audio signals in the sound processing system 1 to be more accurate. Furthermore, in the sound processing system 1, the corresponding speakers 50 are caused to emit the noise cancellation audio signals generated by the sound processing device 100. Consequently, in the sound processing system 1, the noise cancellation audio signals emitted by the speakers 50 can cancel the noise within the vehicle interior at various locations with greater accuracy.

[0063] Furthermore, in the sound processing system 1, if any microphone unit experiences an abnormality, a simulated sound signal is generated based on a sound signal received by a non-abnormal microphone unit, mimicking the sound signal received by the abnormal microphone unit. The system then performs sound signal processing to generate a noise cancellation sound signal, similar to normal operation. In other words, even if any microphone unit experiences an abnormality, the sound processing in the noise cancellation processing unit 162 remains unchanged, allowing the system to generate a noise cancellation sound signal. Thus, by modifying the delay time information and correction value information stored in the microphone information DB 40 to match the connection relationship between each vehicle and component, the sound processing system 1 can handle various vehicles with the same configuration.

[0064] Furthermore, in sound processing system 1, the microphone bodies that receive sound to generate noise-canceling sound signals include a mix of economically efficient microphone bodies 12 (analog microphones) and less economically efficient microphone bodies 22 (digital microphones) that are less susceptible to noise. This allows for greater freedom in selecting, combining, and configuring the various microphone bodies within sound processing system 1. By configuring sound processing system 1 with a mix of analog and digital microphones, the overall cost of sound processing system 1 can be reduced compared to configuring all microphone bodies with digital microphones.

[0065] According to the embodiment described above, the sound processing system 1 comprises an analog microphone section 10, which comprises one or more microphone bodies 12 arranged in the interior of a vehicle M and outputting analog microphone sound signals; a digital microphone section 20, which comprises one or more microphone bodies 22 arranged in the interior of the vehicle and outputting digital sound signals; a DAC 30, which converts a digital sound signal into a digital microphone sound signal; and a signal processing section 160 (including a noise cancellation processing section 162), which comprises a delay processing section 142, wherein the delay processing section 142 delays the analog microphone sound signal based on at least a delay time when the DAC 30 converts a digital sound signal collected at the same time as the analog microphone sound signal into a digital microphone sound signal and outputs the delayed sound signal, wherein the signal processing section 160 performs sound signal processing based on the digital microphone sound signal and the delayed sound signal, thereby enabling sound processing to be performed using analog sound signals (analog microphone sound signals) and digital sound signals, respectively, in a vehicle M where analog microphones and digital microphones are mixed. As a result, the vehicle M equipped with the sound processing system 1 can realize a sound space suitable for the occupants by canceling the noise inside the vehicle interior, such as the noise flowing into the vehicle interior from the outside of the vehicle.

[0066] The above-described embodiment can be expressed as follows.

[0067] A sound processing system comprising:

[0068] Hardware processor; and

[0069] a storage device storing a program,

[0070] The hardware processor reads and executes the program stored in the storage device to perform the following processing:

[0071] At least a first analog sound signal outputted by one or more analog microphones disposed in the vehicle interior is delayed based on a delay time when a digital sound signal outputted by one or more digital microphones disposed in the vehicle interior, which is received at the same time as the first analog sound signal, is converted by a digital-to-analog converter into a second analog sound signal, and the signal is used as a third analog sound signal.

[0072] Sound signal processing is performed based on the second analog sound signal and the third analog sound signal.

[0073] While specific embodiments of the present invention have been described above, the present invention is not limited to these embodiments at all, and various modifications and substitutions can be made without departing from the spirit of the present invention.

Claims

1. A sound processing system, wherein: The sound processing system comprises: One or more analog microphones are disposed in the vehicle interior and output a first analog sound signal; One or more digital microphones, which are disposed in the vehicle interior and output digital sound signals; a digital-to-analog converter that converts the digital audio signal into a second analog audio signal; and a sound signal processing unit including a delay processing unit that delays at least the first analog sound signal based on a delay time and outputs the delayed signal as a third analog sound signal; The delay time is the time it takes for the digital-to-analog converter to convert the digital audio signal into the second analog audio signal. The digital audio signal is a signal received at the same time as the first analog audio signal. The sound signal processing unit performs sound signal processing based on the second analog sound signal and the third analog sound signal.

2. The sound processing system according to claim 1, wherein The sound signal processing unit performs the sound signal processing to cause an acoustic device disposed in the vehicle interior to emit a sound output signal for canceling noise in the vehicle interior based on the second analog sound signal and the third analog sound signal.

3. The sound processing system according to claim 1 or 2, wherein: The sound signal processing unit further includes a sound correction unit that corrects the first analog sound signal or the second analog sound signal using a correction value obtained based on information about the arrangement positions of the analog microphone and the digital microphone in the vehicle interior, or information about the distance between the arrangement positions in the vehicle interior. When an abnormality occurs in the analog microphone, the sound correction unit outputs a simulated sound signal obtained by correcting the second analog sound signal by the correction value as the third analog sound signal.

4. The sound processing system according to claim 1, wherein: The sound signal processing unit further includes a sound correction unit that corrects the first analog sound signal or the second analog sound signal using a correction value obtained based on information about the arrangement positions of the analog microphone and the digital microphone in the vehicle interior, or information about the distance between the arrangement positions in the vehicle interior. When an abnormality occurs in the digital microphone, the sound correction unit outputs a simulated sound signal obtained by correcting the first analog sound signal by the correction value as the second analog sound signal.

5. The sound processing system according to claim 3, wherein: The audio signal processing unit forms a bidirectional direction toward the driver's seat and the passenger seat in the vehicle cabin using the analog microphone and the digital microphone. When an abnormality occurs in one of the analog microphone and the digital microphone, the audio signal processing unit switches to a unidirectional directivity in which the other of the analog microphone and the digital microphone, which is not abnormal, is directed toward the driver's seat. The sound processing system according to claim 1 , wherein: Delaying the first analog sound signal based on the delay time includes delaying by at least the amount of the delay time.

7. A sound processing method, wherein: The sound processing method enables the computer to perform the following processing: At least one first analog audio signal outputted by one or more analog microphones disposed in the vehicle interior is delayed based on a delay time and used as a third analog audio signal. The delay time is the time it takes for the digital-to-analog converter to convert the digital audio signal output by one or more digital microphones disposed in the vehicle interior into the second analog audio signal. The digital sound signal is a signal received at the same time as the first analog sound signal; Sound signal processing is performed based on the second analog sound signal and the third analog sound signal.

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