Recording system and recording method

Abstract

To provide a recording system and a recording method, which suitably protect privacy of a witness when an abnormal situation which is not related to a self-vehicle occurs.SOLUTION: A recording device 10 includes: an acquisition part 21; an event detection part 22; and a recording control part 23. The acquisition part 21 acquires image data obtained by photographing a region including at least the surrounding of a vehicle and voice data obtained by collecting voice of an area including at least the surrounding of the vehicle. The event detection part 22 detects an occurrence of an event in which abnormality of the surrounding of the vehicle is detected and the abnormality of the vehicle is not detected. When the event occurs, the recording control part 23 records restricted voice data in which a prescribed voice is restricted from voice data for a first prescribed period corresponding to the occurrence time of the event is recorded in a recording part 33 together with image data for the first prescribed period.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a recording system and a recording method. [Background technology]

[0002] In recent years, the number of vehicles equipped with drive recorders has been increasing. Drive recorders are used as recording devices that record images of the inside and outside of a vehicle and record the captured data. The data recorded in the drive recorder is used to investigate the cause of an accident when an accident occurs, or to confirm the facts when an incident occurs.

[0003] For example, Patent Document 1 discloses a recording device that collects audio around a vehicle and records images and audio around the vehicle in a recording unit if it determines that the vehicle is being tailgated. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-160630 A Summary of the Invention [Problem to be solved by the invention]

[0005] Here, when an abnormal event not related to the vehicle occurs, such as an accident or incident involving another vehicle, the data from the drive recorder may be provided as witness information to the police, insurance companies, the media, the cloud, etc. The data from the drive recorder may contain personal conversation voices in the vehicle, etc., which are information related to the privacy of the witnesses themselves, and when providing the data as witness information, there is a need to protect the privacy of such witnesses.

[0006] The present invention has been made to solve the above-mentioned problems, and provides a recording system and recording method that effectively protects the privacy of witnesses when an abnormality occurs that is not related to the vehicle. [Means for solving the problem]

[0007] A recording system according to an aspect of the present invention includes an acquisition unit, an event detection unit, and a recording control unit. The acquisition unit acquires image data of an area including at least the periphery of a vehicle, and audio data of an area including at least the periphery of the vehicle. The event detection unit detects the occurrence of an event in which an abnormality is detected around the vehicle, but an abnormality in the vehicle is not detected. When the event occurs, the recording control unit records restricted audio data, in which a predetermined audio is restricted from the audio data for a first predetermined period corresponding to the occurrence time of the event, in the recording unit together with the image data for the first predetermined period.

[0008] A recording method according to one aspect of the present invention includes an acquisition step, an event detection step, and a recording control step. The acquisition step is a step of acquiring image data of an area including at least the periphery of a vehicle, and audio data of an area including at least the periphery of the vehicle. The event detection step is a step of detecting the occurrence of an event in which an abnormality is detected around the vehicle, but an abnormality in the vehicle is not detected. The recording control step is a step of recording, when the event occurs, restricted audio data in which a predetermined audio is restricted from the audio data for a first predetermined period corresponding to the occurrence time of the event, together with the image data for the first predetermined period in a recording unit. Effect of the Invention

[0009] According to the present invention, it is possible to provide a recording system and a recording method that suitably protects the privacy of witnesses when an abnormality not related to the vehicle occurs. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a configuration diagram of a recording apparatus according to a first embodiment. [Diagram 2] FIG. 4 is a diagram showing an example of the relationship between data recorded in a recording section and data recorded in a buffer memory according to the first embodiment. [Diagram 3] FIG. 4 is a diagram showing an example of the relationship between data recorded in a recording section and data recorded in a buffer memory according to the first embodiment. [Figure 4] FIG. 4 is a diagram illustrating an example of the flow of an event detection process according to the first embodiment. [Diagram 5] FIG. 4 is a diagram showing a flow of a recording process of media data according to the first embodiment. [Figure 6] FIG. 11 is a diagram showing an example of the relationship between data recorded in a recording section and data recorded in a buffer memory according to the second embodiment. [Figure 7] FIG. 11 is a diagram showing the configuration of a recording device according to a third embodiment. [Figure 8] FIG. 11 is a diagram showing a flow of a recording process of media data according to the third embodiment. [Figure 9] FIG. 13 is a configuration diagram of a recording device according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present invention will be described below through embodiments of the invention, but the invention according to the claims is not limited to the following embodiments. In addition, not all of the configurations described in the embodiments are necessarily essential as means for solving the problems. For clarity of explanation, the following description and drawings are omitted and simplified as appropriate. In each drawing, the same elements are given the same reference numerals.

[0012] <Embodiment 1> Hereinafter, an embodiment of the present invention will be described with reference to the drawings. A configuration example of a recording system (hereinafter, referred to as a recording device) 10 according to the first embodiment will be described with reference to FIG. 1. FIG. 1 is a configuration diagram of the recording device 10 according to the first embodiment. The recording device 10 may be used, for example, as a drive recorder mounted on a vehicle. The recording device 10 may be a computer device that operates by a processor executing a program stored in a memory. The processor may be, for example, a microprocessor, an MPU (Micro Processing Unit), or a CPU (Central Processing Unit). The memory may be a volatile memory or a non-volatile memory, or may be configured by a combination of a volatile memory and a non-volatile memory. The processor executes one or more programs including a group of instructions for causing a computer to execute an algorithm described with reference to the following drawings.

[0013] The recording device 10 includes a control unit 20, a camera 31, a microphone 32, a recording unit 33, a sensor 34, a display unit 35, and a speaker 36. The control unit 20, the camera 31, the microphone 32, the recording unit 33, the sensor 34, the display unit 35, and the speaker 36 may be directly connected to each other using a predetermined cable or the like, or may be connected to each other via a controller area network (CAN) that is an in-vehicle network. The recording device 10 may also be configured to include components that are realized by the control unit 20. Specifically, the recording device 10 mainly includes an acquisition unit 21, an event detection unit 22, and a recording control unit 23.

[0014] The camera 31 generates image data capturing an area including at least the periphery of the vehicle. In the first embodiment, the camera 31 generates image data capturing an area outside the vehicle, but may generate image data capturing an area inside the vehicle. The microphone 32 generates audio data capturing audio from an area including at least the periphery of the vehicle. In the first embodiment, the microphone 32 captures audio from inside and outside the vehicle to generate audio data. The recording unit 33 may be a hard disk, a card-type memory, or the like, and records the image data and audio data.

[0015] The sensor 34 may be, for example, an acceleration sensor, and may detect impacts and the like that occur when a vehicle equipped with the recording device 10 has an accident or is involved in an accident. Furthermore, the sensor 34 may detect the amount of operation of the brake, accelerator, or steering wheel, and generate vehicle speed and acceleration information. The sensor 34 may also be, for example, a distance measuring sensor or a millimeter wave radar, and may detect the proximity of other vehicles or other objects. The display unit 35 may be a display that plays back image data recorded in the recording unit 33. The speaker 36 plays back audio data recorded in the recording unit 33. The speaker 36 includes an audio amplifier unit and an audio processor (not shown) before the input of the speaker 36, and these are also included when the term "speaker 36" is used.

[0016] Next, a configuration example of the control unit 20 will be described. The control unit 20 has an acquisition unit 21, an event detection unit 22, a recording control unit 23, a buffer memory 24, and a playback control unit 25. Each of the components constituting the control unit 20, such as the acquisition unit 21, the event detection unit 22, the recording control unit 23, and the playback control unit 25, may be software or a module in which processing is performed by a processor executing a program stored in a memory. Alternatively, each of the components constituting the control unit 20 may be hardware such as a circuit or a chip.

[0017] The acquisition unit 21 acquires image data generated in the camera 31 and audio data generated in the microphone 32. Data including image data and audio data may be referred to as media data. In other words, the acquisition unit 21 may acquire media data from the camera 31 and the microphone 32. The image data is still image data or video data. The image data may be generated using a format such as H.264 or H.265. The audio data may be generated using a format such as PCM (Pulse Code Modulation), and the media data, which is video data including image data and audio data, may be generated using MPEG (Moving Picture Experts Group) 2-TS (Transport Stream) or AVI (Audio Video Interleave).

[0018] The acquisition unit 21 outputs media data including image data and audio data to the buffer memory 24. The buffer memory 24 temporarily stores the output media data. The buffer memory 24 may be referred to as an internal memory built into the control unit 20. Temporarily storing may mean, for example, that the buffer memory 24 erases media data after a predetermined period of time has elapsed. Alternatively, temporarily storing may mean that the data output from the acquisition unit 21 is overwritten onto the data in the buffer memory 24 and stored. Alternatively, temporarily storing may mean that, when the buffer memory 24 outputs the media data output from the acquisition unit 21 to the recording control unit 23, the buffer memory 24 erases the output media data.

[0019] Furthermore, the acquisition unit 21 may receive vehicle position information from a positioning system (not shown) such as a Global Navigation Satellite System (GNSS), and supply the position information to the buffer memory 24 together with the media data.

[0020] The event detection unit 22 detects the occurrence of an event by using at least one of the image data acquired from the camera 31 via the buffer memory 24, the audio data acquired from the microphone 32, and the measurement information output from the sensor 34. Specifically, the event detection unit 22 has a surrounding abnormality detection unit 220, a vehicle abnormality detection unit 221, and a determination unit 223.

[0021] The surrounding abnormality detection unit 220 detects the occurrence of an abnormality around the vehicle from the media data. Specifically, the surrounding abnormality detection unit 220 detects the occurrence of an abnormality around the vehicle from the voice data. The abnormality around the vehicle may include abnormalities inside the vehicle as well as abnormalities outside the vehicle. For example, the surrounding abnormality detection unit 220 analyzes the voice data and detects sounds related to abnormalities around the vehicle (referred to as abnormal sounds). The abnormal sounds may include non-verbal sounds and linguistic sounds (utterances). The non-verbal sounds may be, for example, collision sounds, braking sounds, etc. The utterances may be, for example, screams, utterances such as "there's an accident" or "you're tailgating."

[0022] As an example, the surrounding abnormality detection unit 220 extracts a feature amount of the audio signal from the waveform of the audio signal, specifically, from the frequency, the elapsed time from the start of utterance, the volume, etc. The surrounding abnormality detection unit 220 detects the occurrence of an abnormality around the vehicle when the similarity between the extracted feature amount and the feature amount of sample data of a preregistered abnormal sound is equal to or greater than a predetermined threshold. The feature amount can be calculated using existing acoustic analysis technology or voiceprint analysis technology.

[0023] As another example, the surrounding abnormality detection unit 220 uses an acoustic model trained using training data including normal sound data and abnormal sound data to determine whether the voice data includes an abnormal sound. The acoustic model may be an existing acoustic model. For example, the acoustic model outputs a value indicating whether the voice data corresponding to the input includes an abnormal sound. Alternatively, the acoustic model outputs the probability that the voice data corresponding to the input includes an abnormal sound. The surrounding abnormality detection unit 220 detects the occurrence of an abnormality around the vehicle when the probability that the voice data corresponding to the input includes an abnormal sound is equal to or greater than a predetermined value. The surrounding abnormality detection unit 220 may use a feature obtained from the waveform of the voice signal as an input for the acoustic model.

[0024] In addition, when a specific speech content, for example, a scream or an utterance such as "It's an accident" or "He's trolling" is defined as an abnormal sound, the surrounding abnormality detection unit 220 may further estimate the speech content by natural language processing and determine whether it is an abnormal sound. Specifically, the surrounding abnormality detection unit 220 first extracts phonemes from the voice data based on a predetermined acoustic model. Then, the surrounding abnormality detection unit 220 determines whether a speech component is included by comparing the extracted phonemes with a predetermined language model. If a speech component is included, the surrounding abnormality detection unit 220 estimates the speech content using a predetermined language model and determines whether it includes content defined as an abnormal sound. The language model includes a trained voice recognition dictionary. If it is determined that the estimated speech content includes an abnormal sound, the surrounding abnormality detection unit 220 detects the occurrence of an abnormality around the vehicle.

[0025] In addition to or instead of the voice data, the surrounding abnormality detection unit 220 may analyze image data to detect abnormalities around the vehicle, such as collisions between other vehicles or between other vehicles and other objects, rollovers or fires of other vehicles, and abnormal approach between other vehicles such as tailgating. In this case, the surrounding abnormality detection unit 220 may detect abnormalities around the vehicle using an image recognition model that has been trained using image data of normal times, abnormal times of other vehicles, and abnormal times of the vehicle itself as training data. For example, the image recognition model may have a convolutional neural network that receives image data as input and outputs a value indicating whether the image data is normal or abnormal around the vehicle. In addition to or instead of analyzing image data, the surrounding abnormality detection unit 220 may detect the occurrence of an abnormality around the vehicle by detecting the proximity of other vehicles or between other vehicles and other objects using a sensor 34 such as a distance sensor or a millimeter wave radar.

[0026] When the surrounding abnormality detection unit 220 detects the occurrence of an abnormality around the vehicle, it supplies information indicating the occurrence of the abnormality around the vehicle (surrounding abnormality information) to the determination unit 223. The surrounding abnormality information includes the time when the abnormality around the vehicle occurred. Furthermore, the surrounding abnormality information may include the content of the abnormality that occurred.

[0027] The vehicle abnormality detection unit 221 detects the occurrence of an abnormality in the host vehicle, mainly an abnormality related to the running of the host vehicle, from the measurement information output from the sensor 34. For example, when an impact level detected by the sensor 34 operating as an acceleration sensor exceeds a predetermined value, the vehicle abnormality detection unit 221 detects that an abnormality related to the host vehicle has occurred. The impact level exceeding a predetermined value may be rephrased as the acceleration exceeding a predetermined value. Also, for example, when a distance between the host vehicle and another vehicle detected by the sensor 34 operating as a distance measurement sensor is less than a predetermined value, the vehicle abnormality detection unit 221 detects that an abnormality related to the host vehicle has occurred. When the vehicle abnormality detection unit 221 detects the occurrence of an abnormality in the host vehicle, it supplies information indicating that an abnormality in the host vehicle has occurred (host vehicle abnormality information) to the determination unit 223. The host vehicle abnormality information includes the time when the abnormality in the host vehicle has occurred. Furthermore, the host vehicle abnormality information may include the content of the abnormality that has occurred. The vehicle abnormality detection unit 221 may analyze image data in addition to or instead of the measurement information output from the sensor 34, and detect the occurrence of an abnormality in the host vehicle, such as abnormal proximity between the host vehicle and another vehicle.

[0028] The determination unit 223 determines whether or not an event has occurred based on the detection result of the surrounding abnormality detection unit 220 and the detection result of the vehicle abnormality detection unit 221. In the present embodiment 1, a case where an abnormality is detected around the vehicle and an abnormality is not detected in the vehicle (the vehicle itself) is called a first event. Examples of the first event include a collision between other vehicles in the vicinity of the vehicle and a tailgating of another vehicle in the vicinity of the vehicle. The determination unit 223 determines that a first event has occurred when it acquires information indicating that an abnormality has occurred around the vehicle and does not acquire information indicating that an abnormality has occurred in the vehicle itself. The determination unit 223 may detect a second event in which an abnormality in the vehicle is detected in addition to the first event.

[0029] In response to detecting the occurrence of an event, the determination unit 223 supplies information indicating the occurrence of the event (event occurrence information) to the recording control unit 23. The information indicating the occurrence of the event includes the time when the event occurred.

[0030] The recording control unit 23 records the media data stored in the buffer memory 24 in a predetermined file format in the recording unit 33. The media data acquired from the buffer memory 24 includes image data and audio data. In other words, the recording control unit 23 transfers the media data from the buffer memory 24 to the recording unit 33. Specifically, the recording control unit 23 generates a video file including image data and audio data from the media data stored in the buffer memory 24, and records the video file in the recording unit 33 as media data for recording.

[0031] When the occurrence of the first event is detected, the recording control unit 23 generates restricted audio data from audio data of the occurrence period of the first event stored in the buffer memory 24. Then, the recording control unit 23 records the restricted audio data in the recording unit 33 together with image data of the occurrence period of the first event. The occurrence period of the first event may be a predetermined period corresponding to the time when the first event occurs. For example, the occurrence period of the first event may be a predetermined period (first predetermined period) including the time when the first event occurs and the period before and after the time when the first event occurs. As an example, in the occurrence period of the first event, the period before the occurrence time of the first event may be the same as the period after the occurrence time of the first event, or may be longer or shorter than the period after the occurrence time of the first event. Furthermore, the occurrence period of the first event may only include either the period before or after the time when the first event occurs. Furthermore, the restricted audio data may be silent data, or may be audio data with the overall volume reduced. Specifically, when the occurrence of a first event is detected, the recording control unit 23 generates restricted audio data by restricting the audio contained in the audio data from the audio data during the occurrence period of the first event stored in the buffer memory 24. Then, the recording control unit 23 generates a video file including the restricted audio data in place of the audio data during the occurrence period of the first event and image data during the occurrence period of the first event, and records the video file in the recording unit 33 as media data for recording.

[0032] When recording the generated media data for recording in the recording unit 33, the recording control unit 23 may record the media data for recording caused by the first event, i.e., the media data for recording including image data and restricted audio data, in the recording unit 33 as a record related to the event, as overwrite-prohibited data. For example, the recording control unit 23 may specify an address of a memory area in the recording unit 33 where overwriting of data is prohibited, and record the media data for recording in the recording unit 33. Alternatively, the recording control unit 23 may set flag information indicating overwrite prohibition in a header or payload of the media data for recording. The recording control unit 23 may record the media data for recording including image data and audio data caused by the second event in the recording unit 33 as overwrite-prohibited data, as a record related to the event.

[0033] Furthermore, the recording control unit 23 may discard recording media data not resulting from an event, i.e., recording media data including image data and audio data, without recording it in the recording unit 33, or may record it in the recording unit 33 as a normal recording not related to an event. When recording the recording media data in the recording unit 33 as a normal recording, the recording control unit 23 may record the recording media data in the recording unit 33 as overwritable data. For example, the recording control unit 23 may specify an address of a memory area in the recording unit 33 that allows data to be overwritten, and record the recording media data in the recording unit 33. Alternatively, the recording control unit 23 may set flag information indicating overwritability in the header or payload of the recording media data.

[0034] The recording unit 33 records the data output from the recording control unit 23, in other words, the media data transferred from the buffer memory 24 via the recording control unit 23. The recording unit 33 is, for example, a recording medium such as an optical disc or a card-type recording medium.

[0035] The playback control unit 25 acquires the recording media data recorded in the recording unit 33, outputs image data contained in the acquired recording media data to the display unit 35, and outputs audio data contained in the acquired recording media data to the speaker 36, etc.

[0036] In FIG. 1, the recording device 10 includes a playback control unit 25, a display unit 35, and a speaker 36, but a playback device or the like different from the recording device 10 may include the playback control unit 25, the display unit 35, and the speaker 36. In other words, the recording device 10 may not include the playback control unit 25, the display unit 35, and the speaker 36. That is, a playback device or the like including the playback control unit 25, the display unit 35, and the speaker 36 may play back data recorded in the recording unit 33 of the recording device 10. For example, the playback device or the like may be a device that plays back data recorded on a portable recording medium such as an optical disk or a card-type recording medium. The data recorded in the recording unit 33 may be transferred to a portable recording medium.

[0037] Here, the relationship between the data recorded in the recording unit 33 and the data recorded in the buffer memory 24 will be described with reference to FIG. 2. FIG. 2 is a diagram showing an example of the relationship between the data recorded in the recording unit 33 according to the first embodiment and the data recorded in the buffer memory 24. The horizontal axis shown in FIG. 2 indicates the passage of time. Each of D-3 to D+4 indicates media data divided into predetermined periods, which was taken during the occurrence period of the first event. The predetermined period may be called a time frame, and may be, for example, several seconds, several tens of seconds, or several minutes. In FIG. 2, D-2 is the oldest media data taken, and D+4 is the most recently taken media data. Note that the middle part of FIG. 2 shows data newly added to the buffer memory 24 during the predetermined period. That is, the buffer memory 24 may store data other than the data newly added to the buffer memory 24 in the predetermined time frame, for example, unerased data added before the time frame.

[0038] The media data acquired by the acquisition unit 21 is immediately output to the buffer memory 24. Therefore, FIG. 2 shows that the media data acquired by the acquisition unit 21 is stored in the buffer memory 24 as it is. In other words, FIG. 2 shows that the timing at which the acquisition unit 21 acquires the media data and the timing at which the media data is stored in the buffer memory 24 are substantially the same. The term "substantially the same" includes a case where the timing at which the acquisition unit 21 acquires the media data and the timing at which the media data is stored in the buffer memory 24 do not completely match. For example, the term "substantially the same" includes a case where the timing at which the media data is stored in the buffer memory 24 is later than the timing at which the acquisition unit 21 acquires the media data. On the other hand, the media data recorded in the recording unit 33 is temporarily stored in the buffer memory 24 and then recorded in the recording unit 33 by the recording control unit 23. Therefore, the timing at which the media data acquired by the acquisition unit 21 is stored in the buffer memory 24 and the timing at which the media data is recorded in the recording unit 33 are different. Specifically, the timing at which the media data is recorded in the recording unit 33 is later than the timing at which the media data is stored in the buffer memory 24 .

[0039] t-3 to t+3 and ti indicate times. The event detection unit 22 determines whether or not an event occurred during a predetermined period in the past, from time t-3 to t+3. For example, the event detection unit 22 determines whether or not an event occurred at time t between time t-1 and time t. The event detection unit 22 similarly determines whether or not an event occurred at other times.

[0040] For example, at time t-2, the event detection unit 22 determines that the first event has not occurred between time t-3 and time t-2. In this case, the recording control unit 23 may discard the media data D-2 stored in the buffer memory 24 between time t-2 and time t-1 without recording it in the recording unit 33, or may record it in the recording unit 33 as a normal recording not related to an event.

[0041] On the other hand, at time t, the event detection unit 22 determines that the first event occurred at time ti between time t-1 and time t. In this case, the recording control unit 23 replaces the audio data of the media data D stored in the buffer memory 24 during a predetermined period corresponding to time ti, for example, between time t and time t+1, with restricted audio data, and records the replaced audio data in the recording unit 33 as media data D' in which the image data and the restricted audio data are made into a file.

[0042] FIG. 2 shows that the media data that has been completely stored in the buffer memory 24 is recorded in the recording unit 33. That is, the timing at which the media data is recorded in the recording unit 33 is one time frame later than the timing at which the media data is stored in the buffer memory 24. However, the timing at which the media data stored in the buffer memory 24 is recorded in the recording unit 33 is not limited to this. The difference between the two timings may be less than one time frame or may be two or more time frames. For example, the recording control unit 23 may acquire the media data that is being stored in the buffer memory 24, and record the acquired media data in the recording unit 33. Alternatively, when the storage of the media data in the buffer memory 24 is completed, the recording control unit 23 may record the media data in the recording unit 33 after a predetermined period has elapsed from the point at which the storage of the media data is completed, regardless of the time frame.

[0043] Also, in FIG. 2, the recording control unit 23 restricts audio only for media data acquired by the acquisition unit 21 during a period including the first event occurrence time, and records the data in the recording unit 33. In other words, the shooting period (event occurrence period) of the media data subject to audio restriction is limited to a time frame including the first event occurrence time. However, the recording control unit 23 is not limited to this, and may restrict audio for media data acquired by the acquisition unit 21 during a period before or after the period including the first event occurrence time, and record the media data in the recording unit 33. In other words, the shooting period of the media data subject to audio restriction may include a time frame including the first event occurrence time, as well as a time frame before or after the time frame, and the period of the time frame including the first event occurrence time may be set arbitrarily. For example, the recording control unit 23 may record data D-1 in the recording unit 33 as data D' and data D-1' with audio restriction, in addition to data D acquired by the acquisition unit 21.

[0044] In this case, the relationship between the data recorded in the recording unit 33 and the data recorded in the buffer memory 24 is shown in Fig. 3. Fig. 3 is a diagram showing another example of the relationship between the data recorded in the recording unit 33 and the data recorded in the buffer memory 24 according to the first embodiment. When a first event is detected in either a time frame corresponding to the shooting period of each media data in the buffer memory 24 or the next time frame, the recording control unit 23 restricts the audio of the media data and records it in the recording unit 33.

[0045] Specifically, the event detection unit 22 determines at time t-2 that the first event did not occur between time t-3 and time t-2, and determines at time t-1 that the first event did not occur between time t-2 and time t-1. At this time, the recording control unit 23 files the media data D-2 stored in the buffer memory 24 between time t-1 and time t without restricting the audio data, and records the file in the recording unit 33.

[0046] Then, at time t, the event detection unit 22 determines that the first event occurred at time ti, which is between time t-1 and time t. At this time, even if the first event did not occur in the immediately previous time frame, the recording control unit 23 replaces the audio data of the media data D-1 stored in the buffer memory 24 during a predetermined period corresponding to time ti, for example, between time t and time t+1, with restricted audio data, and records the data together with the image data in the recording unit 33 as filed data D-1'.

[0047] Next, the recording control unit 23 replaces the audio data of the media data D stored in the buffer memory 24 with restricted audio data, and records the data together with the image data in the recording unit 33 as filed data D′.

[0048] Next, at time t+1, the event detection unit 22 determines that the first event has not occurred between time t and time t+1. At this time, the recording control unit 23 may directly convert the media data D+1 stored in the buffer memory 24 into a file and record it in the recording unit 33 without restricting the audio data.

[0049] Next, the process of the control unit 20 of the recording device 10 will be described with reference to Figures 4 and 5. Figures 4 and 5 show an example in which the recording period of the media data subject to audio restriction is limited to a time frame including the time when an event occurs, as in Figure 2, but the present invention is not limited to this.

[0050] FIG. 4 is a diagram showing a flow of the event detection process according to the first embodiment. First, the acquisition unit 21 acquires media data including image data and audio data and outputs it to the buffer memory 24, and the buffer memory 24 stores the media data (step S10). Next, the surrounding abnormality detection unit 220 of the event detection unit 22 determines whether or not an abnormal sound in the surroundings has been detected from the audio data included in the media data stored in the buffer memory 24 (step S11). If an abnormal sound in the surroundings has been detected from the audio data (Yes in step S11), the surrounding abnormality detection unit 220 supplies the surrounding abnormality information to the determination unit 223 and proceeds to the process at step S12. On the other hand, if an abnormal sound in the surroundings has not been detected from the audio data (No in step S11), the surrounding abnormality detection unit 220 returns the process to step S10.

[0051] In step S12, the vehicle abnormality detection unit 221 of the event detection unit 22 determines whether or not an abnormality has been detected in the host vehicle from the measurement information output from the sensor 34. If an abnormality has been detected in the host vehicle (Yes in step S12), the vehicle abnormality detection unit 221 supplies the host vehicle abnormality information to the determination unit 223 and returns the process to step S10. On the other hand, if an abnormality has not been detected in the host vehicle (No in step S12), the vehicle abnormality detection unit 221 does not supply the host vehicle abnormality information to the determination unit 223 and proceeds to step S13.

[0052] In step S13, the determination unit 223 of the event detection unit 22 determines that a first event has occurred when the surrounding abnormality information has been acquired and the host vehicle abnormality information has not been acquired. The determination unit 223 then generates event occurrence information and supplies the event occurrence information to the recording control unit 23 (step S14). After that, the process returns to step S10 and the processes from step S10 onwards are repeatedly executed.

[0053] 5 is a diagram showing a flow of a media data recording process according to the first embodiment. First, the acquisition unit 21 acquires media data including image data and audio data and outputs it to the buffer memory 24, and the buffer memory 24 stores the media data (step S20). Next, the recording control unit 23 determines whether or not a first event has occurred before starting to record the media data stored in the buffer memory 24 into the recording unit 33 (step S21). That is, the recording control unit 23 determines whether or not event occurrence information has been acquired from the determination unit 223 of the event detection unit 22.

[0054] When it is determined that the first event has occurred (Yes in step S21), the recording control unit 23 extracts audio data from the media data including the timing when the first event occurred during the shooting period, and generates restricted audio data by restricting the audio (step S22).Then, the recording control unit 23 generates a video file including the image data and the restricted audio data, and records it in the recording unit 33 (step S23).Then, the process returns to step S20, and the processes from step S20 onwards are repeatedly executed.

[0055] On the other hand, when the recording control unit 23 determines that the first event has not occurred (No in step S21), it directly files the media data captured during the period when the first event has not occurred, and records the file in the recording unit 33 (step S24). That is, the recording control unit 23 files the media data stored in the buffer memory 24 without restricting the sound, and records the file in the recording unit 33. When the recording control unit 23 determines that the first event has not occurred, the recording control unit 23 may be configured not to record the file in the recording unit 33. Thereafter, the process returns to step S20, and the processes in and after step S20 are repeatedly executed.

[0056] In the above description, when the occurrence of the first event is detected, the recording control unit 23 records the media data with audio restriction in the recording unit 33. However, in addition to this, when the occurrence of the first event is detected, the recording control unit 23 may also record the media data with no audio restriction in the recording unit 33. For example, the recording unit 33 has a first recording area and a second recording area, and the media data stored in the buffer memory 24 is recorded as it is in the first recording area as a normal recording not related to the event detection result. On the other hand, in the second recording area, data with audio restriction from the media data whose shooting period includes the timing when the first event occurred may be recorded as an event record related to the detection of the first event.

[0057] As described above, the recording device 10 according to the first embodiment can replace the audio data of the media data, whose shooting period includes the timing of the occurrence of the first event, with restricted audio data in which the audio is restricted, and record the media data in the recording unit 33. In this way, when an abnormality not related to the vehicle occurs, the recording device 10 does not record audio that may include the speech of the driver of the vehicle or conversations between the occupants, so that the privacy of the witness can be appropriately protected when providing information as a witness. Note that the recording device 10 can record image data and audio data in the recording unit 33 for media data shot during a period in which the first event does not occur. Therefore, when an abnormality related to the vehicle occurs, the recorded media data can be used to investigate the cause of the accident.

[0058] Furthermore, when the recording device 10 erases the audio data and records it in the recording unit 33 when the first event occurs, the amount of data to be recorded can be reduced compared to when recording media data including audio data. This reduces the number of times that the recording unit 33 overwrites and records media data, allowing the recording unit 33 to record media data for a longer period of time.

[0059] <Embodiment 2> Next, a description will be given of embodiment 2. In embodiment 2, when a first event occurs, the recording control unit 23 stores media data for a period during which the first event occurs in the recording unit 33, distinguishing it from cases in which the event does not occur. However, the recording control unit 23 restricts only audio for a specific period from the media data stored distinguishing it from cases in which the event does not occur.

[0060] For example, the specific period during which audio is restricted and recorded may be a predetermined period (second predetermined period) before the occurrence of the first event in the first event occurrence period (first predetermined period). During and immediately after an accident, audio that may be important evidence of the accident is likely to be picked up, so it is preferable to record audio without restricting it. Therefore, when the first event occurs, the recording control unit 23 may generate restricted audio data in which audio is restricted from audio data of a predetermined period before the occurrence of the first event. Then, the recording control unit 23 may record the restricted audio data together with image data of a predetermined period (second predetermined period) before the occurrence of the first event in a specific storage area of ​​the recording unit 33. Then, the recording control unit 23 may record audio data of a predetermined period (third predetermined period) after the occurrence of the first event as it is, together with image data of a predetermined period (third predetermined period) after the occurrence of the first event in a specific storage area of ​​the recording unit 33. The second predetermined period may include a period before the first predetermined period, and may not include a part of the period before the occurrence of the first event included in the first predetermined period. The second predetermined period is not strictly limited to a period not including the period during and immediately after the occurrence of the accident, and may include a period during and immediately after the occurrence of the accident. Similarly, the third predetermined period may include a period after the first predetermined period, and may not include a portion of the period after the occurrence of the first event included in the first predetermined period. The third predetermined period is not necessarily limited to a period including the period during and immediately after the occurrence of the accident, and may include a period not including the period during and immediately after the occurrence of the accident.

[0061] 6 is a diagram showing an example of the relationship between data recorded in the recording unit 33 and data recorded in the buffer memory 24 according to the second embodiment. In this example, the recording unit 33 has a first recording area which is a normal recording area not related to the first event detection result, and a second storage area which is an event recording area related to the first event detection result. The timing at which the media data is recorded in the recording unit 33 is two time frames later than the timing at which the media data is stored in the buffer memory 24.

[0062] The recording control unit 23 records the media data stored in the buffer memory 24 in the first recording area of ​​the recording unit 33 regardless of the result of the first event detection.

[0063] Furthermore, when the occurrence of a first event is detected for each media data in the buffer memory 24, the recording control unit 23 restricts the audio of a specific period of the media data and records it in the second storage area of ​​the recording unit 33.

[0064] Specifically, the event detection unit 22 determines that the first event occurred between time t-1 and time t. At this time, the recording control unit 23 replaces the audio data of the media data D-1 stored in the buffer memory 24, which corresponds to the time frame from time t-2 to time t-1, which is one time frame before the time t-1 to time t when the first event occurred, with restricted audio data, and records it together with the image data in the second storage area of ​​the recording unit 33. Instead of or in addition to the above, the recording control unit 23 may replace the audio data of the media data corresponding to the time t-1 to time t1 when the first event occurred with restricted audio data, and record it together with the image data in the second storage area of ​​the recording unit 33.

[0065] At this time, the recording control unit 23 records the audio data of the media data D stored in the buffer memory 24, which corresponds to the period from time t-1 to time t when the first event occurred, together with the image data, in the second storage area of ​​the recording unit 33. Alternatively or in addition to the above, the recording control unit 23 may replace the audio data of the media data corresponding to the period from time t-1 to time t when the first event occurred with restricted audio data, and record this in the second storage area of ​​the recording unit 33 together with the image data.

[0066] At this time, the recording control unit 23 also records the audio data of media data D+1, which is stored in the buffer memory 24 and corresponds to the time frame from time t to time t+1, which is one time frame after the time t-1 to time t when the first event occurred, together with the image data in the second memory area of ​​the recording unit 33.

[0067] Instead of or in addition to the above-mentioned recording area, the recording unit 33 may have a recording area for recording only the voice data during the first event occurrence period, and a recording area for recording only the image data during the first event occurrence period. The recording device 10 may receive from the user a designation of a period during which voice is restricted, for example, after driving, generate media data in which voice is restricted for the designated period, and record the media data in the recording unit 33.

[0068] Instead of or in addition to the above-mentioned recording area, the recording unit 33 may have a recording area for recording voice-restricted media data during the first event occurrence period, and a recording area for recording voice-unrestricted media data during the first event occurrence period. The recording device 10 may receive a designation of a period during which voice is restricted, for example, after driving, from the user, and record the voice-restricted media data and voice-unrestricted media data during the designated period in the recording unit 33 in combination.

[0069] In this way, the recording device 10 of embodiment 2 can achieve the same effects as embodiment 1 while recording the audio inside the vehicle cabin at the time the first event occurs and after the first event occurs, and can reliably record the audio necessary to provide information while protecting the privacy of witnesses.

[0070] <Embodiment 3> Next, a third embodiment will be described. The third embodiment is characterized in that, when a first event occurs, the recording control unit 23 stores in the recording unit 33 media data in which only a predetermined sound is restricted during the period in which the first event occurs. The predetermined sound to be restricted is, for example, the voice of an occupant in the vehicle cabin. In the following description, the voice to be restricted is the voice of an occupant in the vehicle cabin, but is not limited thereto.

[0071] 7 is a configuration diagram of a recording device 10a according to embodiment 3. The recording device 10a differs from the recording device 10 in that it includes a control unit 20a instead of the control unit 20. The control unit 20a also differs from the control unit 20 in that it includes a restricted audio detection unit 26 in addition to the components of the control unit 20.

[0072] When the occurrence of the first event is detected, the restricted voice detection unit 26 functions as an occupant voice detection unit that detects the voice of an occupant in the vehicle cabin from the voice data included in the media data stored in the buffer memory 24. For example, the restricted voice detection unit 26 may perform a voiceprint analysis of the voice data during the occurrence period of the first event and determine whether or not the voice data includes the voice of a pre-registered occupant. The restricted voice detection unit 26 may also detect the voice from the direction in which the occupant sits as the voice of the occupant by a beamforming process. In this case, the recording device 10 may have a plurality of microphones 32. When the restricted voice detection unit 26 determines that the voice data includes the voice of a pre-registered occupant, it supplies information indicating the voice of the occupant to the recording control unit 23. The restricted voice detection unit 26 may also detect the voice of an occupant in the vehicle cabin by comparing the voice of a microphone installed in the vehicle cabin with that of a microphone installed outside the vehicle cabin or by canceling the voice.

[0073] When the occurrence of the first event is detected, the recording control unit 23 generates restricted voice data from the voice data during the occurrence of the first event based on the information indicating the occupant's voice. The restricted voice data may be data obtained by deleting the voice signal corresponding to the occupant's voice from the original voice signal, or may be data obtained by attenuating only the voice signal corresponding to the occupant's voice. The recording control unit 23 records the restricted voice data in the recording unit 33 together with the image data during the occurrence of the first event.

[0074] 8 is a diagram showing the flow of a media data recording process according to embodiment 3. In this diagram, the same steps as in FIG. 5 are denoted by the same reference numerals.

[0075] In response to acquiring the event occurrence information from the determination unit 223 (Yes in step S21), the restricted voice detection unit 26 determines whether or not an utterance by an occupant is detected from the voice data (step S30).

[0076] When the restricted voice detection unit 26 detects the occupant's voice (Yes in step S30), it supplies information indicating the occupant's voice to the recording control unit 23, and the process proceeds to step S31. In step S31, in response to acquiring the information indicating the occupant's voice, the recording control unit 23 extracts voice data from the media data including the timing when the first event occurred during the shooting period, and generates restricted voice data from the voice data by restricting the voice corresponding to the occupant's voice. The recording control unit 23 then generates a video file including the image data and the restricted voice data, and records it in the recording unit 33 (step S32).

[0077] On the other hand, if the restricted voice detection unit 26 does not detect the occupant's voice (No in step S30), the process proceeds to step S33. In step S33, the recording control unit 23 directly files the media data including the timing when the first event occurred during the shooting period, and records the file in the recording unit 33. However, the media data filed in this case may be recorded separately from the media data filed when the occurrence of the first event is not detected.

[0078] The restricted sound detection unit 26 may be configured integrally with the surrounding abnormality detection unit 220.

[0079] In this way, when a first event occurs, the recording device 10a according to the third embodiment records media data in which only a predetermined sound is restricted during the period when the first event occurs. Therefore, for example, when an accident occurs, only private conversations in the vehicle are erased from the sound, and the impact sound of the accident and the screams and chatter of people in the vicinity can be recorded. This makes it possible to reliably record sounds necessary for providing information while protecting the privacy of witnesses.

[0080] In the above description, when the first event occurs, the voices corresponding to the voices of the passengers in the vehicle cabin are uniformly restricted. However, this is not limited to the above, and when the first event occurs, the voices corresponding to the voices related to the abnormality related to the first event among the voices of the passengers in the vehicle cabin may not be subject to restriction. In other words, the restricted voice detection unit 26 may detect, from the voice data included in the media data stored in the buffer memory 24, voices other than those related to the abnormality among the voices of the passengers in the vehicle cabin. In this case, the restricted voice detection unit 26 may use a predetermined language model to determine whether the detected voices of the passengers in the vehicle cabin are related to a predetermined abnormality, such as screams, "It's an accident," or "They're tailgating." This makes it possible to more appropriately protect the privacy of witnesses and more reliably record voices necessary for providing other information.

[0081] <Embodiment 4> Next, a fourth embodiment will be described. The fourth embodiment is characterized in that, when a first event occurs, the recording control unit 23 stores in the recording unit 33 media data in which sounds other than sounds corresponding to the type of abnormality during the period in which the first event occurs are restricted.

[0082] 9 is a configuration diagram of a recording device 10b according to the fourth embodiment. The recording device 10b differs from the recording device 10a in that the recording device 10b includes a control unit 20b instead of the control unit 20a. The control unit 20b also differs from the control unit 20a in that the control unit 20b includes an event detection unit 22b instead of the event detection unit 22.

[0083] Event detection section 22b differs from event detection section 22 in that, instead of surrounding abnormality detection section 220, event detection section 22b includes surrounding abnormality detection section 220b.

[0084] The surrounding abnormality detection unit 220 b basically has the same functions as the surrounding abnormality detection unit 220 , but includes an abnormality type determination unit 225 .

[0085] The abnormality type determination unit 225 determines the type of abnormality (abnormality type) around the vehicle from the voice data in which the abnormality around the vehicle is detected. Here, the abnormality types may be classified into, for example, "accident," "near miss," and "tailgating." For example, when the voice data includes an impact sound such as "crash" or an utterance of "accident," the abnormality type determination unit 225 determines the abnormality type as "accident." When the voice data includes a conversation such as "there is a car tailgating," the abnormality type determination unit 225 determines the abnormality type as "tailgating." Then, the abnormality type determination unit 225 supplies information indicating the abnormality type to the determination unit 223.

[0086] When the determination unit 223 determines that the first event has occurred, the determination unit 223 adds information indicating the abnormality type to the event occurrence information, and supplies the event occurrence information to the restricted sound detection unit 26.

[0087] When the restricted voice detection unit 26 acquires event occurrence information, it detects voice corresponding to the abnormality type from the voice data as a voice to be restricted. For example, when the abnormality type is "accident", the restricted voice detection unit 26 detects conversation voices in the vehicle cabin such as "accident" or "crash" from the voice data. When the abnormality type is "tailgating", the restricted voice detection unit 26 detects conversation voices in the vehicle cabin such as "tailgating", "dangerous", and "nearby" from the voice data. Then, the restricted voice detection unit 26 determines voices other than the detected voices, that is, voices not related to the abnormality type, as voices to be restricted, and supplies information indicating the voices to be restricted to the recording control unit 23.

[0088] When a first event occurs, the recording control unit 23 generates restricted audio data by restricting audio corresponding to the type of abnormality from the audio data during the first event occurrence period based on information indicating the audio to be restricted. In other words, when a first event occurs, the recording control unit 23 generates restricted audio data from the audio data during the first event occurrence period in which audio related to the type of abnormality is not restricted and audio not related to the type of abnormality is restricted. The recording control unit 23 then records in the recording unit 33 the media data in which audio corresponding to the type of abnormality is restricted from the audio during the event occurrence period.

[0089] In this way, according to the recording device 10b of embodiment 4, when an abnormality occurs around the vehicle, audio unrelated to the abnormality is restricted to more appropriately protect the privacy of witnesses, while audio related to the abnormality is not restricted, thereby making it possible to more reliably record audio necessary for providing information.

[0090] The present invention is not limited to the above embodiment, and can be modified as appropriate without departing from the spirit of the present invention. For example, the surrounding abnormality detection process by the surrounding abnormality detection units 220 and 220b, the vehicle abnormality detection process by the vehicle abnormality detection unit 221, and the abnormality type determination process by the abnormality type determination unit 225 may be performed by an external device (not shown) instead of the recording device. In other words, the surrounding abnormality detection units 220 and 220b, the vehicle abnormality detection unit 221, and the abnormality type determination unit 225 may not be included in the recording device. In this case, the recording device acquires various detection results or determination results from the external device via a communication means (not shown) and supplies them to the determination unit 223. Similarly, the restricted sound detection unit 26 may not be included in the recording device. The recording device acquires information indicating the sound to be restricted from the external device via a communication means (not shown) and supplies it to the recording control unit 23.

[0091] In the first to fourth embodiments, the surrounding abnormality detection unit 220 determines whether the surroundings of the vehicle are normal or abnormal (that is, abnormality related to at least one of the vehicle itself and the other vehicle) from at least one of the voice data and the image data, and detects the occurrence of an abnormality around the vehicle. However, instead of this, the surrounding abnormality detection unit 220 may determine whether the surroundings are normal, abnormal in the vehicle itself, or abnormal in the other vehicle not related to the vehicle from at least one of the voice data and the image data. In this case, instead of step S12 in FIG. 4, the surrounding abnormality detection unit 220 may determine whether an abnormality in the other vehicle not related to the vehicle has been detected from the media data stored in the buffer memory 24. Then, when an abnormality in the other vehicle is detected, the surrounding abnormality detection unit 220 may supply other vehicle abnormality information indicating that an abnormality in the other vehicle has been detected to the determination unit 223. Then, instead of step S13 in FIG. 4, the determination unit 223 may determine that a first event has occurred in response to acquiring the other vehicle abnormality information. That is, step S12 in FIG. 4 may be omitted.

[0092] Furthermore, some or all of the above-described embodiments can be described as, but are not limited to, the following supplementary notes. (Appendix 1) An acquisition unit that acquires image data of an area including at least the periphery of a vehicle and audio data of an area including at least the periphery of the vehicle; an event detection unit that detects the occurrence of an event in which an abnormality is detected around the vehicle and an abnormality is not detected in the vehicle; a recording control unit that, when the event occurs, records in a recording unit restricted voice data obtained by restricting a predetermined voice from the voice data of a first predetermined period corresponding to the occurrence time of the event, together with the image data of the first predetermined period; A recording system comprising: (Appendix 2) The event detection unit a surrounding abnormality detection unit that detects an abnormality around the vehicle from the voice data; a vehicle abnormality detection unit that detects an abnormality of the vehicle based on measurement information of a sensor of the vehicle; have 2. A recording system as described in appendix 1. (Appendix 3) When the event occurs, the recording control unit recording, in the recording unit, restricted voice data in which a predetermined voice is restricted from the voice data for a second predetermined period including a period before the occurrence of the event, together with the image data for the second predetermined period; The audio data for a third predetermined period including a period after the occurrence of the event is recorded in the recording unit together with the image data for the second predetermined period. 3. A recording system according to claim 1 or 2. (Appendix 4) an occupant speech detection unit that detects speech of an occupant in a cabin of the vehicle from the voice data; When the event occurs, the recording control unit restricts a sound corresponding to a detected voice utterance of the occupant from the sound data for the first predetermined period or the sound data for a second predetermined period including a period before the event occurs, and generates the restricted sound data. 4. A recording system according to any one of claims 1 to 3. (Appendix 5) The occupant utterance detection unit further includes an abnormality-related utterance detection unit that detects an utterance related to the abnormality from an utterance of the occupant, When the event occurs, the recording control unit generates the restricted voice data from the voice data for the first predetermined period or the voice data for a second predetermined period including a period before the event occurs, without restricting a voice corresponding to an utterance by the occupant regarding the abnormality. 5. A recording system as described in Appendix 4. (Appendix 6) an abnormality type determination unit that determines a type of abnormality from the voice data; When the event occurs, the recording control unit restricts a sound corresponding to a type of the abnormality from the sound data for the first predetermined period or the sound data for a second predetermined period including a period before the event occurs, and generates the restricted sound data. 6. A recording system according to any one of claims 1 to 5. (Appendix 7) An acquisition step of acquiring image data of an area including at least the surroundings of the vehicle and audio data of an area including at least the surroundings of the vehicle; an event detection step of detecting an occurrence of an event in which an abnormality is detected around the vehicle and an abnormality is not detected on the vehicle; a recording control step of recording, in a recording unit when the event occurs, restricted voice data in which a predetermined voice is restricted from the voice data of a first predetermined period corresponding to the occurrence time of the event together with the image data of the first predetermined period; A recording method comprising: [Explanation of symbols]

[0093] 10, 10a, 10b Recording system (recording device) 20, 20a, 20b Control section 21 Acquisition Department 22, 22b Event detection section 23 Recording control section 24 Buffer Memory 25 Playback control section 26 Restricted Audio Detector 31 Camera 32 Microphone 33 Recording Department 34 Sensors 35 Display section 36 Speaker 220, 220b Surrounding abnormality detection unit 221 Vehicle Abnormality Detection Unit 223 Judgment section 225 Abnormality type determination unit

Claims

1. An acquisition unit that acquires image data obtained by capturing an image of an area including at least the periphery of a vehicle and audio data obtained by capturing audio of an area including at least the periphery of the vehicle; an event detection unit that detects the occurrence of an event in which an abnormality is detected around the vehicle and an event in which an abnormality is not detected around the vehicle, and determines a type of the abnormality around the vehicle; a recording control unit that, when the event occurs, records restricted voice data obtained by restricting voices not related to the determined abnormality type from the voice data for a first predetermined period corresponding to the occurrence time of the event, together with the image data for the first predetermined period in a recording unit; A recording system comprising:

2. An acquisition unit that acquires image data of an area including at least the periphery of a vehicle and audio data of audio of an area including at least the periphery of the vehicle; an event detection unit that detects the occurrence of an event in which an abnormality is detected around the vehicle and an abnormality is not detected in the vehicle; a restricted voice detection unit that detects, when the event is detected, an utterance of an occupant of the vehicle by a voiceprint analysis of the voice data or by detecting a voice coming from a direction in which the occupant of the vehicle is seated by a beamforming process; a recording control unit that, when the event occurs, records in a recording unit, restricted voice data obtained by erasing a voice signal corresponding to the voice of the occupant from the voice data for a first predetermined period corresponding to the occurrence time of the event, or by attenuating the voice signal corresponding to the voice of the occupant, together with the image data for the first predetermined period; A recording system comprising:

3. When the event occurs, the recording control unit recording, in the recording unit, restricted voice data in which a predetermined voice is restricted from the voice data for a second predetermined period including a period before the occurrence of the event, together with the image data for the second predetermined period; The audio data for a third predetermined period including a period after the occurrence of the event is recorded in the recording unit together with the image data for the third predetermined period.

3. A recording system according to claim 1 or 2.

4. an occupant speech detection unit that detects speech of an occupant in a cabin of the vehicle from the voice data; When the event occurs, the recording control unit restricts a sound corresponding to a detected voice utterance of the occupant from the sound data for the first predetermined period or the sound data for a second predetermined period including a period before the event occurs, and generates the restricted sound data. A recording system according to any one of claims 1 to 3.

5. An acquisition step of acquiring image data obtained by capturing an image of an area including at least the periphery of the vehicle, and audio data obtained by capturing audio of an area including at least the periphery of the vehicle; an event detection step of detecting an occurrence of an event in which an abnormality is detected around the vehicle and an abnormality is not detected around the vehicle, and determining a type of the abnormality around the vehicle; a recording control step of, when an event occurs in which an abnormality is detected around the vehicle and no abnormality is detected in the vehicle, recording restricted voice data in which voices not related to the determined abnormality type are restricted from the voice data for a first predetermined period corresponding to the occurrence time of the event, together with the image data for the first predetermined period in a recording unit; A recording method comprising:

Images