Information processing device

Abstract

The aim is to make it easier to visually identify which of the known possible abnormal sounds the sound being analyzed is most similar to. [Solution] The information processing device stores a database that associates information indicating the frequency band of a predetermined noise for each type of source of a predetermined noise, which is an abnormal sound that may be generated from a vehicle. Based on the database and audio data including sounds generated from a given vehicle, the device maps the frequency band of one or more predetermined noises and the frequency band of candidate noises included in the audio data onto a graph in which frequency is assigned to at least one axis.

Description

Technical Field

[0001] The present disclosure relates to a noise analysis device.

Background Art

[0002] There is a technology for analyzing and displaying abnormal noises generated from a vehicle. In this regard, for example, Patent Document 1 discloses a vehicle inspection display method in which sound data is acquired from a vehicle, the type of component that is the sound source is specified based on the sound pressure characteristics and frequency characteristics of the calculated sound data, it is determined whether the component sound is a normal sound or an abnormal sound, an image of the sound data and frequency data is generated, and the specified components, vehicle type, and the determination result of normal sound / abnormal sound are displayed on a display.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present disclosure is to make it easy to visually recognize which of the known abnormal noises that the sound to be analyzed is close to in terms of the possibility of occurrence.

Means for Solving the Problems

[0005] One aspect of the present disclosure is An information processing device that provides information about abnormal noises generated from a vehicle, comprising: a storage unit that stores a database associating information indicating the frequency band of a predetermined noise for each type of source of a predetermined noise that may be generated from the vehicle; and a control unit that performs the following: mapping the frequency bands of one or more predetermined noises included in the database and frequency data obtained by converting audio data including sounds generated from a predetermined vehicle into the frequency domain onto a graph in which frequency is assigned to at least one axis.

[0006] Furthermore, other embodiments include a program that causes a computer to execute the information processing method performed by the information processing device described above, or a computer-readable storage medium that non-temporarily stores the program. [Effects of the Invention]

[0007] According to this disclosure, it is possible to make it easier to visually identify which of the known abnormal sounds that the sound being analyzed is most similar to. [Brief explanation of the drawing]

[0008] [Figure 1] A diagram showing an overview of the graph displayed by the server device according to the embodiment. [Figure 2] A diagram illustrating the components of a server device according to this embodiment. [Figure 3] A flowchart of the process performed by the server device according to the embodiment. [Figure 4] A diagram showing a graph displayed by the server device according to the embodiment. [Figure 5] A flowchart of the processes performed by the server device in the modified example. [Figure 6] A diagram showing a graph displayed by the server device relating to the second modification. [Modes for carrying out the invention]

[0009] (overview) There has always been a need for technology to identify abnormal noises emanating from vehicles.

[0010] In this regard, there is a technology that analyzes abnormal noises emitted from a vehicle under inspection, whether it is stationary or in motion, and displays what kind of abnormal noise it is.

[0011] For example, conventional abnormal noise analysis devices can analyze the frequency bands of abnormal noises contained in audio data collected from a moving vehicle and display the vehicle parts that may have been the source of the noise, along with the probability that they were actually the source.

[0012] Specifically, conventional noise analysis devices acquire audio data from a moving vehicle using a sound pressure visualization device and identify the part of the vehicle where the noise is occurring, thereby estimating the component that is the source of the noise. At this time, the noise analysis device can display the name of the component that is the source of the noise and the probability that that component is the source of the noise. For example, the noise analysis device can output displays such as "transmission gear noise 82%" and "transmission oil pump 10%" as the estimated source of the noise.

[0013] However, there is room for improvement in conventional display methods. For example, when an unusual noise is occurring and there are multiple possible sources of that noise, there is a need to be able to see at a glance which source's frequency range is most likely to correspond to the noise's frequency range. In conventional methods, where possible sources are listed and displayed along with their probabilities, if even a small change occurs in the predetermined conditions used to determine whether a source is relevant, the displayed source and its probability may change to a completely different source and its probability, and the originally displayed source may disappear altogether. In this case, it is difficult for the user to consistently grasp all possible sources. However, it is desirable for the user to be able to consistently grasp the possible sources at a glance, taking into account the various driving conditions that change as the noise occurs.

[0014] An information processing apparatus according to one aspect of the present disclosure is an information processing apparatus that provides information regarding abnormal sounds generated from a vehicle, and includes a storage unit that stores a database associating information indicating a frequency band of a predetermined noise, which is an abnormal sound that may be generated from the vehicle, with each type of source of the predetermined noise; and a control unit that maps, on a graph in which frequencies are assigned to at least one axis, the frequency band of each of one or more of the predetermined noises included in the database and frequency data obtained by converting voice data including sounds generated from a predetermined vehicle into a frequency domain.

[0015] The predetermined noise is an abnormal sound that may be generated from a vehicle. The predetermined noise includes all abnormal sounds that may occur, not limited to the actually generated abnormal sounds.

[0016] The frequency data is data obtained by converting voice data including sounds generated from a predetermined vehicle into a frequency domain. The frequency data can be obtained, for example, by performing a Fourier transform on the voice data. The sound generated from a predetermined vehicle includes, for example, a sound including noise generated from a vehicle during travel.

[0017] The control unit converts the sound generated from a predetermined vehicle into a frequency domain, and maps, on a graph in which frequencies are assigned to at least one axis, the frequency band of the sound generated from the vehicle and the frequency band corresponding to the predetermined noise included in the database.

[0018] According to such a configuration, the information processing apparatus according to the present disclosure can make it easy to visually recognize which of the known abnormal sounds that may occur the sound generated from the vehicle is close to.

[0019] Further, in the graph, when a frequency band having a volume equal to or greater than a predetermined value included in the frequency data overlaps with the frequency band of the predetermined noise, the control unit may highlight the corresponding area compared to other areas.

[0020] As a result, the information processing apparatus according to the present disclosure can clearly present to the user that the frequency band of the sound generated from a predetermined vehicle matches the frequency band of the predetermined noise.

[0021] Further, the plurality of predetermined noises are noises whose frequency bands change according to the traveling speed of the vehicle, and the database may store the relationship between the frequency bands of the plurality of predetermined noises and the traveling speed of the vehicle.

[0022] Further, the voice data is associated with the traveling speed of the vehicle, and the control unit may update the information indicating the frequency band of the predetermined noise shown in the graph to information indicating a frequency band corresponding to the traveling speed of the vehicle.

[0023] According to such a configuration, even when the frequency band of the predetermined noise changes according to the traveling speed of the vehicle, the predetermined noise in an appropriate frequency band can be displayed.

[0024] Further, the control unit may calculate the frequency band of the predetermined noise based on the traveling speed of the vehicle.

[0025] As a result, the information processing apparatus according to the present disclosure can accurately obtain the frequency band of the predetermined noise.

[0026] Hereinafter, specific embodiments of the present disclosure will be described based on the drawings. The hardware configuration, module configuration, functional configuration, etc. described in each embodiment are not intended to limit the technical scope of the disclosure only to those unless otherwise specified.

[0027] (Embodiment) [Outline of Processing Performed by Server Device] The outline of the processing executed by the server device according to the embodiment will be described with reference to FIG. 1. FIG. 1 is a diagram showing an outline of a graph displayed by the server device according to the embodiment. The information processing apparatus according to one aspect of the present disclosure is realized as the server device 100.

[0028] The server device 100 displays graph 1000. Graph 1000 represents a graph showing multiple default noises and the frequency bands of sounds that are candidates for noise (abnormal noise) generated from the vehicle. Graph 1000 is, for example, a map in which frequency is represented on the vertical axis and part type is represented on the horizontal axis. Specifically, on graph 1000, a rectangular shape is displayed in the region where the part type that is the source of a particular abnormal noise intersects with the frequency band of that particular abnormal noise. Frequencies may be displayed from 0 to 6000 Hz, and part types may be divided into engine system (ENG in Figure 1), drive system (HEV in Figure 1), and vehicle system (vehicle system) (vehicle in Figure 1). For each part type, multiple types of abnormal noises are defined for each frequency. For example, in the engine system, airflow noise, balancer gear noise, chain noise, etc., are defined.

[0029] Furthermore, the display method for the various types of abnormal noises defined above may be changed depending on whether the abnormal noise occurs while the vehicle is stationary or while it is in motion. For example, abnormal noises occurring while the vehicle is stationary Sounds are represented by rectangles with a single dashed line, such as belt tensioner noise, and noises that occur while driving may be represented by rectangles with two dashed lines, such as balancer gear noise.

[0030] The candidate frequency band, which is the frequency range of sound actually generated from the vehicle, may be indicated by a dashed line at the corresponding frequency position, as shown in Graph 1000. The candidate frequency band can be, for example, the frequency range of sound generated from the vehicle in which the volume is above a predetermined value. As shown in Figure 1, if there are no abnormal noises (default noises) corresponding to the frequencies in the candidate frequency band, the dashed rectangle representing the candidate frequency band will not overlap with any rectangle representing default noises. When this is displayed in Graph 1000, the user can understand that the sound emanating from the vehicle does not correspond to any of the known abnormal noises.

[0031] On the other hand, if a candidate frequency band overlaps with a rectangle corresponding to any of the predefined noises, the user can visually recognize that the sound emanating from the vehicle is a known anomaly.

[0032] Therefore, the server device 100 according to this embodiment can provide a visually clear relationship between the frequency band of the sound to be analyzed originating from the vehicle and the frequency band of known abnormal sounds that may occur.

[0033] [Server device configuration] Next, the hardware and software configuration of the system including the server device 100 will be described. Figure 2 is a diagram illustrating the components of the server device 100 according to this embodiment.

[0034] The server device 100 can be configured as a computer having a processor (CPU, GPU, etc.), main memory (RAM, ROM, etc.), and auxiliary storage (EPROM, hard disk drive, removable media, etc.). The auxiliary storage contains an operating system (OS), various programs, various tables, etc., and by executing the programs stored therein, various functions (software modules) that match a predetermined purpose, as described later, can be realized. However, some or all of the functions may be realized as hardware modules by hardware circuits such as ASICs and FPGAs.

[0035] The server device 100 is comprised of a control unit 110, a storage unit 120, a communication unit 130, and a display unit 140.

[0036] The control unit 110 is a computing unit that realizes various functions of the server device 100 by executing a predetermined program. The control unit 110 can be implemented by a hardware processor such as a CPU. The control unit 110 may also be configured to include RAM, ROM (Read Only Memory), cache memory, etc.

[0037] In this embodiment, the control unit 110 of the server device 100 is configured to have two software modules: a noise acquisition unit 111 and a mapping unit 112. Each software module may be implemented by the control unit 110 (CPU, etc.) executing a program stored in the storage unit 120. The information processing performed by the software modules is synonymous with the information processing performed by the control unit 110 (CPU, etc.).

[0038] The noise acquisition unit 111 acquires audio generated from the vehicle while the server device 100 is in operation. The unit acquires the audio data, including the noise. The noise acquisition unit 111 also records the acquired audio data generated from the vehicle in the storage unit 120.

[0039] The mapping unit 112 maps the frequency bands of the audio data, including voices generated from the vehicle, acquired by the noise acquisition unit 111, and the frequency bands of the default noises included in the database stored in the storage unit 120 onto a graph with frequency represented on at least one axis. Here, default noise refers to abnormal sounds that may be generated from the vehicle. The database contains information indicating the frequency bands of multiple default noises. The mapping unit 112 also analyzes (frequency converts) the audio data, including voices generated from the vehicle, acquired by the noise acquisition unit 111, and processes the audio data to acquire the frequency bands (candidate frequency bands) of sounds with a volume above a predetermined value. Sounds with a volume above a predetermined value in the audio data can be said to be candidates for default noise. The mapping unit 112 also acquires data from the database stored in the storage unit 120 (described later) indicating the frequency bands of default noises, which are abnormal sounds that may be generated from the vehicle.

[0040] The memory unit 120 is a means for storing information and is composed of storage media such as RAM, magnetic disks, and flash memory. The memory unit 120 stores programs executed by the control unit 110, data used by those programs, and so on.

[0041] The communication unit 130 is a wireless communication interface for connecting the server device 100 to an external network. The communication unit 130 is configured to communicate with external devices via, for example, a wireless LAN or a cellular communication network such as 3G, 4G, or 5G.

[0042] The display unit 140 is a display that shows graph 1000. The display unit 140 may be a touch panel display, a liquid crystal display, or an organic EL (Electro-Luminescence) display.

[0043] Note that the configuration shown in Figure 2 is just one example, and all or part of the illustrated functions may be performed using specially designed circuits. Furthermore, program storage and execution may be performed using combinations of main memory and auxiliary memory other than those shown.

[0044] [Server device processing] Next, the specific details of the processing performed by the server device 100 according to one embodiment of this disclosure will be described. Figure 3 is a flowchart of the processing performed by the server device 100 according to the embodiment. Figure 3 describes the process by which the server device 100 maps both the frequency band of the voice acquired from the vehicle and the frequency band of the default noise onto a graph.

[0045] When the server device 100 receives an operation to start voice-based analysis of abnormal noises, it begins the operation that starts from step S10. If the server device 100 uses voice generated from the vehicle in real time for abnormal noise analysis, the server device 100 may start processing in conjunction with the vehicle starting up.

[0046] First, in step S10, the noise acquisition unit 111 recognizes the vehicle to be inspected. Specifically, the noise acquisition unit 111 may acquire the ID of the vehicle to be inspected using CAN communication or the like.

[0047] Next, in step S11, the noise acquisition unit 111 of the server device 100 acquires audio data including sounds generated from the vehicle and converts it into the frequency domain. Here, the frequency band of sounds with a volume above a predetermined value among the sounds generated from the vehicle is called the candidate frequency band. In step S11, the mapping unit 112 also analyzes the conversion results by the noise acquisition unit 111, The frequency bands (candidate frequency bands) of sounds in the audio data that have a volume level above a predetermined value are obtained.

[0048] Next, in step S12, the mapping unit 112 acquires data indicating the frequency band of a predetermined noise, which is an abnormal sound that may be generated from the vehicle, and data corresponding to the vehicle recognized in S10. Specifically, the mapping unit 112 acquires data indicating the frequency band of a predetermined noise by referring to the database stored in the storage unit 120. The mapping unit 112 also acquires data indicating the vehicle to be inspected, such as the model of the vehicle to be inspected, years of use, and current or past driving conditions (driving speed, acceleration, direction of travel, etc.). The data indicating the current or past driving conditions is linked to the audio data acquired in S11.

[0049] Next, in step S13, the mapping unit 112 calculates the expected frequency band of the default noise to be generated based on the vehicle data acquired by the noise acquisition unit 111. For example, the mapping unit 112 generates data indicating the structure of the vehicle body to be inspected based on data indicating the model of the vehicle to be inspected. Then, the mapping unit 112 may calculate the frequency band of the default noise to be generated based on the data indicating the structure of the vehicle body to be inspected. The default noise frequency band may be calculated each time based on the vehicle data mentioned above, or it may be one stored in a database.

[0050] Next, in step S14, the mapping unit 112 displays a graph showing the frequency bands of the audio data and a graph showing the frequency bands of the default noise. Specifically, the mapping unit 112 maps the frequency bands (candidate frequency bands) of sounds with a volume above a predetermined value from the audio data, including the audio generated from the vehicle under inspection acquired by the noise acquisition unit 111, onto a graph in which frequency is represented on at least one axis. Then, the mapping unit 112 maps the frequency bands of multiple default noises included in the database stored in the storage unit 120 onto the same graph. At this time, the mapping unit 112 may gray out or hide default noises on the graph that it has determined, based on vehicle data, etc., are unlikely to occur or have an extremely low probability of occurring.

[0051] Next, in step S15, the mapping unit 112 determines whether the frequency band of sounds with a volume level above a predetermined value (candidate frequency band) among the audio data acquired by the noise acquisition unit 111 overlaps with the frequency band of the default noise. In this step, if the mapping unit 112 determines that the frequency band of sounds with a volume level above a predetermined value (candidate frequency band) among the audio data including sounds generated from the vehicle overlaps with the frequency band of the default noise, it makes a positive determination.

[0052] If the result in this step is positive, the process proceeds to step S16.

[0053] If the result in this step is negative, the process ends.

[0054] If the process proceeds to step S16, the mapping unit 112 highlights the name of the default noise overlapping the candidate frequency band and a graph showing the frequency band of that default noise.

[0055] Figure 4 shows a graph displayed by the server device 100 according to the embodiment. In steps S14 to S16 described in Figure 3, the mapping unit 112 displays a graph 1000 as shown in Figure 4.

[0056] Graph 1000 shows a graph representing multiple default noises and the frequency bands (candidate frequency bands) of sounds with a volume level above a predetermined value, including voice data generated from the vehicle. Graph 1000 is a map in which, for example, frequency is represented on the vertical axis and the type of component is represented on the horizontal axis. Specifically, on Graph 1000, rectangular shapes are displayed in the region where the type of component that is the source of each predetermined noise intersects with the frequency band of each predetermined noise. Frequencies may be displayed from 0 to 6000 Hz, and the types of components may be divided into engine system, drive system, and vehicle system (vehicle body). For each type of component, multiple types of abnormal noises are displayed for each frequency band. For example, in the engine system, airflow noise, balancer gear noise, chain noise, etc. are displayed.

[0057] Furthermore, the display method for the various types of abnormal noises shown as described above may be changed depending on whether the abnormal noise occurs while the vehicle is stationary or while it is in motion. For example, abnormal noises that occur while the vehicle is stationary may be displayed as rectangles represented by a dashed line, such as belt tensioner noise, while abnormal noises that occur while the vehicle is in motion may be displayed as rectangles represented by a double dashed line, such as balancer gear noise.

[0058] Furthermore, the frequency bands (candidate frequency bands) of sounds with a volume level above a predetermined value among the audio data, including voices generated from the vehicle, may be indicated by dashed lines at the corresponding frequency band positions, as shown in Graph 1000. As shown in Figure 1, if there is no default noise corresponding to a candidate frequency band, the dashed rectangle representing the candidate frequency band will not overlap with any rectangle representing a default noise frequency band.

[0059] Conversely, if there is a default noise corresponding to a candidate frequency band, the dashed rectangle representing the candidate frequency band will overlap with a rectangle representing the frequency band of one of the default noises. Then, on graph 1000, the rectangle representing the frequency band of the default noise that overlaps with the dashed rectangle representing the candidate frequency band, and the name of that default noise, are highlighted (300a and 300b in Figure 4). For example, the rectangle representing the frequency band of the corresponding default noise may be shown with a thicker line than the initial value. In graph 1000, default noise in frequency bands that do not overlap with the candidate frequency bands is represented by a line of the thickness set by the initial value.

[0060] When Graph 1000 displays in this way, users can understand which of the existing abnormal noises the sound (unusual noise) emanating from the vehicle corresponds to, or whether it does not correspond to any of them. Furthermore, even if the sound (unusual noise) emanating from the vehicle does not correspond to an existing abnormal noise, users can visually understand which of the existing abnormal noises the sound is closest to.

[0061] As described above, the server device 100 in this embodiment analyzes the sound acquired from the vehicle, identifies its frequency band, and maps the graph representing the identified frequency band with a graph showing the frequency band of a predetermined noise stored separately. This allows the server device 100 to provide in an easily viewable format whether the sound being analyzed corresponds to, or closely resembles, one of the known abnormal noises that may occur.

[0062] (First variation) Depending on the vehicle's speed, the presence or absence, or frequency, of each predetermined abnormal noise expected to be generated by the vehicle may change. In this case, the presence or absence, or the expected frequency range, of the predetermined noises that may occur will also change depending on the vehicle's speed when the audio data was recorded, so it is necessary to update these on the graph each time.

[0063] Therefore, the server device 100 may calculate the frequency band of the default noise to be displayed on the graph based on the driving speed of the vehicle under inspection at the time the sound to be analyzed was generated, and update its display position.

[0064] For example, the speed of the vehicle being inspected changes as the audio data is played back. Therefore, a playback button for the audio data, a seek bar, etc., may be added to the screen viewed by the user. Alternatively, the server device 100 may obtain the vehicle's speed according to the playback position of the audio data, calculate the frequency band of the default noise, and then update the display position of the default noise on the graph.

[0065] Figure 5 is a flowchart of the processes performed by the server device 100 in the modified example.

[0066] The processes from step S20 to step S22 are executed independently of the processes shown in Figure 3.

[0067] First, in step S20, the mapping unit 112 identifies the vehicle's speed at any given point in time within the audio data, which includes voice signals emanating from the vehicle. In this embodiment, the audio data corresponds to the data representing the vehicle's speed in the vehicle data.

[0068] Next, in step S21, the mapping unit 112 calculates whether or not a predetermined noise occurs and, if so, the frequency band, based on the data representing the vehicle speed included in the vehicle data for each time step included in the audio data.

[0069] Next, in step S22, the mapping unit 112 updates the graph displayed in step S14 based on the frequency band of the default noise calculated in step S21. For example, if the mapping unit 112 is playing back the sound of a vehicle traveling at a speed range where the default noise does not occur, it does not display a graph showing the default noise on graph 1000. Conversely, if the mapping unit 112 is playing back the sound of a vehicle traveling at a speed range where the default noise occurs, it displays a graph showing the default noise in the frequency band calculated in step S21. In this case, the graph showing the default noise changes according to the speed of the vehicle when the audio to be analyzed was recorded. Specifically, the position of the rectangular shape showing the frequency band of the default noise on graph 1000 moves according to the speed of the vehicle when the audio to be analyzed was recorded. The process in step S22 is executed repeatedly. Note that the processes in steps S20 and S21 are executed only once each time the process in Figure 5 is executed.

[0070] As described above, the server device 100 in the first modified example can accurately reflect the frequency band of a predetermined noise, which may change depending on the driving speed of the vehicle being inspected, on the graph 1000.

[0071] (Second variation) Users may find it easier to understand abnormal noises emanating from a vehicle by using onomatopoeic words that closely resemble the sounds they hear, rather than by understanding them in terms of frequency bands. Therefore, the mapping unit 112 may display an axis representing onomatopoeic words instead of frequencies on the frequency axis of graph 1000. Figure 6 shows graph 2000 displayed by a server device according to the second modified example. In the example in Figure 6, the onomatopoeic words are represented from lowest to highest frequency as follows: "Go," "Hyuu-Hyuun," "Been," "Keeen," and "Shoo."

[0072] In this modified version, the processing is the same as in the previously described embodiment, except that the frequency display in the graph is replaced with an onomatopoeic expression.

[0073] Note that the onomatopoeic representation of Graph 2000 in Figure 6 is just one example, and other expressions may be used.

[0074] (Other variations) The embodiments described above are merely examples, and this disclosure will be applied without departing from its essence. These may be modified and implemented as appropriate. For example, the processes and means described in this disclosure can be freely combined and implemented, provided that no technical inconsistencies arise.

[0075] Furthermore, the mapping unit 112 may acquire data indicating the engine speed (or vehicle speed) at the time step corresponding to the audio data. Based on the audio data and the corresponding engine speed (or vehicle speed), the unit may calculate whether or not a predetermined noise occurs for each time step included in the audio data, and if so, the frequency band.

[0076] The present disclosure can also be realized by supplying a computer program implementing the functions described in the embodiments above to a computer, and having one or more processors in the computer read and execute the program. Such a computer program may be provided to the computer by a non-temporary computer-readable storage medium that can be connected to the computer's system bus, or it may be provided to the computer via a network. Non-temporary computer-readable storage mediums include, for example, any type of disk such as magnetic disks (floppy disks, hard disk drives (HDDs), etc.), optical disks (CD-ROMs, DVDs, Blu-ray discs, etc.), read-only memory (ROM), random access memory (RAM), EPROM, EEPROM, magnetic cards, flash memory, optical cards, and any type of medium suitable for storing electronic instructions. [Explanation of symbols]

[0077] 100... Server device 110... Control Unit 111...Noise acquisition section 112...Mapping Section 120...Storage section 130... Communications Department

Claims

1. An information processing device that provides information regarding abnormal noises generated from a vehicle, A storage unit that stores a database that associates information indicating the frequency band of a predetermined noise with each type of source of a predetermined noise that may be generated from the vehicle, Mapping the frequency bands of one or more of the predetermined noises included in the database and the frequency data obtained by converting audio data including sound generated from a predetermined vehicle into the frequency domain onto a graph in which frequency is assigned to at least one axis, A control unit that performs the following: An information processing device having

2. The control unit, In the graph, if a frequency band containing the frequency data with a volume level above a predetermined value overlaps with the frequency band of the predetermined noise, the corresponding region is highlighted compared to other regions. The information processing apparatus according to claim 1.

3. The multiple predetermined noises are noises whose frequency band changes according to the vehicle's travel speed. The database stores the relationship between the frequency bands of the multiple predetermined noises and the vehicle's travel speed. The information processing apparatus according to claim 1 or 2.

4. The aforementioned audio data is associated with the vehicle's speed. The control unit, The information indicating the frequency band of the predetermined noise shown in the graph is updated to information indicating the frequency band corresponding to the vehicle's travel speed. The information processing apparatus according to claim 3.

5. The control unit, Based on the vehicle's travel speed, the frequency band of the predetermined noise is calculated. The information processing apparatus according to claim 4.

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