JP2006235732A - Drive recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive recorder for monitoring suspicious persons or the like, by effectively using a configurations necessary for a drive recorder. <P>SOLUTION: A driver recorder 1 is provided with a camera 2, a buffer memory 4 and a recording part 5 for recording image data. A mode-setting part 8 determines the operating status of a vehicle by classifying it into a traveling status and a stopping and parking status, and when the determined operating status is a traveling status, the mode-setting part 8 sets the operation mode of the drive recorder 1 as a traveling mode; and when the determined operating status is stopping and parking state, the mode-setting part 8 sets the operating mode as the stopping and parking mode. A main control part 10 makes the recording part 5 record image data, when it has established that "the magnitude of the acceleration of a vehicle is larger than a first threshold" in the traveling mode, and makes the recording part 5 record the image data, when it has established that "the magnitude of the acceleration of the acceleration of the vehicle is larger than a threshold which is smaller than the first threshold" in the stopping and parking mode. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a dry recorder for a moving body such as a vehicle, and more particularly to a drive recorder that also has a monitoring camera function during parking.

  In the event of a vehicle accident, a so-called drive recorder has been proposed in which the situation from the time of the accident to a few seconds before is recorded as an image for the purpose of leaving objective evidence for subsequent verification of the cause of the accident.

  On the other hand, so-called on-board storms that attempt to steal goods and the like from the inside of a parked vehicle are a problem, and a technique for preventing or suppressing this is required.

  In view of such problems related to theft, the following Patent Document 1 discloses a theft prevention system that attempts to photograph a suspicious person who has given a physical action to a vehicle.

JP 2000-128031 A

  However, in order to realize the anti-theft system of Patent Document 1, a configuration different from that required for the drive recorder is newly required, which is inefficient.

  An object of this invention is to provide the drive recorder which can monitor a suspicious person etc. effectively using the structure required for a drive recorder in view of said point.

  In order to achieve the above object, a drive recorder according to the present invention is a drive recorder attached to a moving body, and temporarily stores a camera for photographing an imaging target and image data corresponding to a video signal from the camera. A buffer memory that stores the image data, a recording unit that can record the image data stored in the buffer memory, and a main unit that controls the recording operation of the image data by the recording unit based on the magnitude of acceleration of the moving body. The control unit and the driving state of the moving body is determined by dividing into a driving state and a parking / stopping state, and when the determined driving state is the driving state, the operation mode of the drive recorder is set to the driving mode, A mode setting unit that sets the operation mode to a parking / stopping mode when the determined driving state is a parking / stopping state, and the main control unit includes the travel In the vehicle mode, the recording operation is controlled based on a comparison result between the magnitude of the acceleration and a predetermined first threshold value, while the magnitude of the acceleration is smaller than the first threshold value in the parking / stopping mode. The recording operation is controlled based on a comparison result with a threshold value.

  The magnitude of acceleration generated in the vehicle due to so-called on-board storm when parked or stopped is smaller than the magnitude of acceleration due to a collision accident that the drive recorder should originally detect, but if configured as described above, a relatively small acceleration It is possible to detect the occurrence of a suspicious person who tries to storm the vehicle and record the captured image. In addition, since an acceleration sensor, a recording unit, and the like that are inherently necessary for the drive recorder are used to provide the monitoring function during parking and stopping as described above, it is extremely efficient.

  Specifically, for example, when the magnitude of the acceleration reaches the first threshold value or more in the travel mode, the main control unit records the data including the image data a predetermined time before that time. To record.

  Further, for example, the parking / stopping state is a state including a parking state and a stopping state, and the mode setting unit determines the driving state of the moving body by dividing it into a traveling state, a parking state, and a stopping state. When the determined driving state is a parking state, the operation mode is set to a monitoring mode, and when the determined driving state is a stop state, the operation mode is set to a stop mode.

  For example, when the magnitude of the acceleration reaches a second threshold value that is smaller than the first threshold value in the monitoring mode, the main control unit receives data including the image data after that time point. Record in the recording unit.

  By referring to the data recorded in the monitoring mode, it is possible to identify a suspicious person or the like.

  In addition, for example, when the magnitude of the acceleration reaches a second threshold value that is smaller than the first threshold value in the monitoring mode, it is preferable to further include a notification unit that performs notification according to the second threshold value.

  Thereby, while suppressing suspicious action by a suspicious person etc., a user can be notified that there was a storm on the vehicle. Further, if the notification is the reproduction of the image data, the suspicious person or the like can be specified.

  Further, for example, the notification unit may include a communication circuit that communicates with an external device, and may transmit notification information corresponding to the notification to the external device via the communication circuit.

  As a result, it is possible to immediately notify the user or the like that an abnormal acceleration has occurred in the parked moving body. In addition, if image information is included in the notification information, it is possible to recognize the presence of a suspicious person, identify a suspicious person, and the like using an external device (for example, a computer).

  Further, for example, when the operation mode shifts from a mode different from the monitoring mode to the monitoring mode, power supply to the camera is cut off, but the magnitude of the acceleration is the second threshold value in the monitoring mode. When the above is reached, the power supply to the camera may be resumed.

  Thereby, power saving is achieved.

  Further, for example, the mode setting unit performs the classification of the driving state of the moving body based on a video signal from the camera.

  In addition, for example, the mode setting unit includes a boarding determination unit that determines whether or not there is a person inside the moving body, and whether the driving state of the moving body is a parking state based on the determination result. Determine whether or not.

  For example, the boarding determination unit determines whether there is a person inside the moving body based on a video signal obtained by photographing the inside of the moving body.

  In addition, for example, the drive recorder further includes another camera that captures the inside of the moving body, and the boarding determination unit is configured to detect a person inside the moving body based on a video signal from the other camera. It is determined whether or not there is.

  Further, for example, the boarding determination unit determines whether or not there is a person inside the moving body based on a measurement result of a weight sensor capable of measuring a weight by a person inside the moving body.

  For example, the mode setting unit determines whether or not the driving state of the moving body is a traveling state based on the magnitude of the acceleration.

  Further, for example, a camera control unit that changes the shooting condition of the camera according to the type of the operation mode set by the mode setting unit may be further provided.

  Thereby, it is possible to perform appropriate photographing according to the type of operation mode.

  Specifically, for example, the camera control unit changes at least one of the shooting conditions among the camera orientation, the angle of view, the focal length, the frame frequency, and the sensitivity according to the type of the operation mode.

  A camera direction control unit that changes the direction of the camera according to the direction of the acceleration when the magnitude of the acceleration reaches a second threshold value that is smaller than the first threshold value in the monitoring mode. It may be.

  As a result, it is possible to fit a suspicious person or the like who gave the acceleration as described above into the imaging region.

  In addition, for example, a motion vector detection unit that detects a motion vector of the imaging target based on the video signal in the monitoring mode, and a camera direction control unit that changes the orientation of the camera according to the detected motion vector. You may make it prepare.

  Further, for example, when there is a motion vector detection unit that detects a motion vector of the imaging target based on the video signal in the monitoring mode, and a moving subject having the motion vector in the monitoring mode, the subject is You may make it further provide the camera direction control part which changes the direction of the said camera according to the said motion vector so that it may be settled in the imaging | photography area | region of a camera.

  Further, for example, a zoom magnification control unit that changes the angle of view of the camera so that the subject is photographed in an enlarged manner may be provided.

  If comprised as mentioned above, it will become possible to image | photograph a suspicious person etc. continuously, and identification of a suspicious person etc. will become easy.

  Further, for example, the recording method of the image data in the recording unit may be different between the traveling mode and the monitoring mode.

  For example, the recording method is an encryption processing method for the image data to be recorded in the recording unit.

  In addition, for example, the main control unit causes the recording unit to record the image data in an erasable format in the monitoring mode, while the image data is not erasable in the recording unit in the traveling mode. Let me record.

  Further, for example, the recording area of the recording unit that records the image data may be different between the traveling mode and the monitoring mode.

  By doing so, it is possible to change the presence / absence of encryption processing, the method, the erasability, etc., between the traveling mode and the monitoring mode. As a result, the convenience of the user is increased and the alteration of the image data recorded in the running mode can be prevented.

  As described above, according to the drive recorder of the present invention, a suspicious person or the like can be monitored by effectively using the configuration necessary for the drive recorder.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a drive recorder (moving object image recording apparatus) according to the present invention will be specifically described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the drive recorder 1 according to the present embodiment.

  1 includes a camera 2, an image processing circuit 3, a buffer memory 4, a recording unit 5, an acceleration sensor 6, an impact detection unit 7, a mode setting unit 8, a main control unit 10, a camera control unit 12, and a notification unit. 13. Also. The display device 14 is a display device such as a liquid crystal display that constitutes a car navigation system or the like provided in the vehicle. The display device 14 may be considered to be provided in the notification unit 13. In this case, the drive recorder 1 includes the display device 14. Further, the display device 14 may be incorporated in the drive recorder 1.

  The drive recorder 1 is attached to a vehicle (not shown) such as an automobile. The drive recorder 1 is, for example, a vehicle rearview mirror (not shown) so that the camera 2 can image (capture) an imaging target (landscape) in front of the vehicle (direction of travel) through a windshield (not shown). It can be attached to the backside of the machine. However, the installation location of the drive recorder 1 in the vehicle is not limited to the room mirror. For example, you may attach to the roof of a vehicle, a side mirror (not shown), etc. Further, if necessary, the drive recorder 1 may be attached to any part of the vehicle so that the imaging object (landscape) behind the vehicle (opposite to the traveling direction) can be imaged. The drive recorder 1 may be mounted at an arbitrary location of the vehicle so that the imaging object (landscape) in the direction of the image can be captured. In the following description, when it is simply referred to as “vehicle”, it means a vehicle to which the drive recorder 1 is mounted as described above.

  The camera 2 is for imaging (capturing) an imaging target of the drive recorder 1, and is composed of, for example, a CCD (Charge Coupled Devices) that converts an image corresponding to the imaging target into a video signal (electrical signal). . For example, the CCD captures 30 images per second. That is, the frame frequency (frame rate) is, for example, 30 frames / second.

  The image processing circuit 3 converts a video signal (image captured by the camera 2) from the camera 2 into image data. Specifically, for example, digital data corresponding to the video signal output from the CCD is created, and the digital data is subjected to appropriate processing (compression processing, etc.) (this data is hereinafter simply referred to as “image”). Data ”) is output to the buffer memory 4 in the subsequent stage.

  The buffer memory 4 is a semiconductor memory such as a DRAM (Dynamic Random Access Memory) that temporarily stores (stores) the image data output from the image processing circuit 3. The buffer memory 4 can store image data (moving images) for several seconds to several tens of seconds in time series. When all of the recording capacity has been used up and image data can no longer be stored, the oldest image data is deleted and the latest image data is stored instead (the oldest stored image data) Overwrite the data with the latest image data).

  The recording unit 5 records part of the image data stored in the buffer memory 4. The recording unit 5 is a portable recording medium such as a memory card. However, a recording medium fixed in the drive recorder 1 so that the user cannot carry it alone may be adopted as the recording unit 5. The main control unit 10 determines at which time point the image data is recorded by the recording unit 5.

  The acceleration sensor 6 detects the magnitude and direction of acceleration of the vehicle to which the drive recorder 1 is attached. It is not always necessary to provide the acceleration sensor 6 in the drive recorder 1 itself. For example, when an acceleration sensor having a function equivalent to that of the acceleration sensor 6 is provided in the vehicle, the magnitude and direction of the detected acceleration may be transmitted to the drive recorder 1 using wired or wireless communication.

  The mode setting unit 8 determines the driving state of the vehicle to which the drive recorder 1 is attached by classifying the driving state into at least a traveling state and a parking / stopping state, and the determined driving state corresponds to a traveling state corresponding to the traveling state and parking / stopping state. When in the parking / stopping state, the operation mode of the drive recorder 1 is set to the traveling mode and the parking / stopping mode, respectively.

  The parking / stopping state is a state including a parking state corresponding to parking and a stopping state corresponding to stopping. The stop state refers to a state satisfying at least “the vehicle is stopped”. The parking state refers to a state satisfying at least “the vehicle is stopped” and “the passenger such as the driver is not in the vehicle”. Therefore, the parking state can also be regarded as a concept included in the stop state.

  The mode setting unit 8 further determines the parking / stopping state by dividing the parking state into a parking state and a stopping state, and when the determined driving state is a parking state corresponding to parking and a stopping state corresponding to stopping, The operation mode is set to a monitoring mode (parking mode) and a stop mode, respectively.

  The impact detection unit 7 determines whether or not an abnormal impact (abnormal impact) is applied to the vehicle based on a comparison result between the magnitude of the acceleration detected by the acceleration sensor 6 and a predetermined impact threshold value. For example, it is detected whether or not a collision accident has occurred. The comparison result by the impact detection unit 7 is transmitted to the main control unit 10. The impact threshold value used for comparison with the magnitude of the acceleration is changed according to the operation mode set by the mode setting unit 8. In the travel mode, the monitoring mode, and the travel mode, the impact threshold values are a first impact threshold value, a second impact threshold value, and a third impact threshold value, respectively.

  The control unit 10 exchanges signals (information) with the buffer memory 4, the recording unit 5, the impact detection unit 7, the mode setting unit 8, the camera control unit 12 and the notification unit 13, which will be described later, and controls them. And the contents of recording data to be recorded in the recording unit 5 are instructed.

When a collision accident or the like occurs at a certain timing T1 when the set operation mode is the traveling mode, and an acceleration having a magnitude equal to or greater than the first impact threshold is detected, the main control unit 10 The accident recording data a is recorded in the recording unit 5 by controlling the memory 4 and the recording unit 5. This first impact threshold is set to 0.4 × 9.8 m / s ² (= 0.4 G), for example.

  The accident record data a includes image data for a predetermined time before timing T1 (for example, at the time of a collision) or for a predetermined time before and after timing T1. That is, the image data from the predetermined time before the timing T1 to the timing T1, or the image data from the predetermined time before the timing T1 to the timing T1, and the image data from the timing T1 to the predetermined time after the timing T1. Is included in the accident record data a. In addition, “position information given from a GPS (Global Positioning System) (not shown), time information (including date) given from a clock device (not shown), speed information specifying a vehicle speed given from a speed sensor (not shown), etc. at the timing T1 "Is preferably included in the accident record data a. The accident record data a is handled as objective evidence for verifying the cause of the accident.

On the other hand, when the operation mode is the monitoring mode, the impact threshold value used for comparison with the magnitude of the acceleration is the second impact threshold value. The second impact threshold is smaller than the first impact threshold, and is set to a value that can detect that the suspicious person vibrates the vehicle. For example, the second impact threshold is set to about 0.05 × 9.8 m / s ² (= 0.05 G) to 0.1 × 9.8 m / s ² (= 0.1 G). Then, at a certain timing T2 when the operation mode is the monitoring mode, an acceleration having a magnitude equal to or greater than the second impact threshold (hereinafter referred to as “abnormal acceleration”) is caused by the suspicious person applying vibration or the like to the vehicle. When detected, the main control unit 10 controls the buffer memory 4 and the recording unit 5 to cause the recording unit 5 to record monitoring recording data.

  The monitoring record data includes image data after timing T2. For example, image data from a timing T2 to a predetermined time after the timing T2 is included in the monitoring recording data. Note that image data before and after the timing T2 may be included in the monitoring record data. Further, like the accident record data a, the monitoring record data may include time information and the like. In consideration of the limited recording capacity of the recording unit 5, the amount of image data (that is, the recording time) included in the monitoring recording data may be smaller than that of the accident recording data a. From the image data included in the monitoring record data, it is possible to reproduce a video relating to a suspicious person or the like who has given vibration to the vehicle, and it becomes possible to determine the suspicious person after the fact.

  Further, when an abnormal acceleration is detected in the monitoring mode, the notification unit 13 performs a notification (hereinafter referred to as “abnormal notification”) to notify that such an acceleration has occurred. This abnormality notification is performed by, for example, light emission or sound output by a light emitting element such as an LED (Light Emitting Diode) (not shown) provided in the drive recorder 1. Further, for example, the abnormality notification may be performed by sound emission by a horn provided in the vehicle or lighting or blinking of a lighting device (both not shown) such as a headlight. In this case, the notification unit 13 transmits a necessary signal wired or wirelessly to a vehicle control unit (not shown) provided in a vehicle that controls sound emission of the horn, lighting of the lighting device, and the like. Will be notified of abnormality.

  Further, at the same time as the light emission or the like, or instead of the light emission or the like, the display device 14 may display a display indicating that an abnormal acceleration is detected. This display is also a kind of “abnormality notification”. A signal necessary for causing the display device 14 to perform the display as described above is transmitted from the notification unit 13 to the display device 14 in a wired or wireless manner.

  When abnormal acceleration is detected, it is preferable to notify abnormality immediately after that. Alternatively or additionally, an abnormality notification (particularly, display by a display device) may be performed, for example, when a vehicle engine (not shown) is started (at the start of operation). More specifically, when an ignition switch (not shown) is turned on to switch from a state where the engine is not operating to a state where the engine is operating, or for a predetermined time (for example, several milliseconds to several seconds). After the elapse of time, abnormality notification may be started. Further, when the abnormality is notified at the start of driving, the user may be notified of the magnitude of the acceleration detected during the monitoring mode, the number of times the abnormal acceleration is detected, or the like by display or voice on the display device 14. . In addition, the image data in the monitor recording data can be reproduced as a video by display on the display device 14 or the like. If it is determined that the user can delete the monitoring record data, the monitoring record data can be deleted from the recording unit 5 by operating an input unit (not shown) of the display device 14 or the like. The monitoring record data can be deleted from the recording unit 5 at an arbitrary timing.

  In addition, the notification unit 13 is provided with a communication circuit (not shown) that can communicate with an external device (an external device of the drive recorder 1), and responds to the abnormality notification via the communication circuit. Notification information to be transmitted may be transmitted to the external device. Here, the external device is, for example, a mobile phone or a computer owned by the user, a computer of a predetermined contact (such as a security company, a police station, or an insurance company). They all have a communication function and are registered in advance so that the notification information is transmitted. The notification information transmitted from the notification unit 13 is transmitted to the computer or the like via a communication network such as the Internet network. The notification information may include the monitoring record data. Thereby, it is possible to recognize the presence of the suspicious person and specify the suspicious person by using the video displayed on the computer or the like.

  Further, the notification information may include image data that is not included in the monitoring record data. For example, when the image data included in the monitoring record data is for 10 seconds after the occurrence of the abnormal acceleration, the image data obtained by the subsequent photographing is continuously transmitted to the computer or the like. It is not always necessary to include image data in the notification information. A message or the like that simply reports that abnormal acceleration has occurred may be used as the notification information.

  When the operation mode is the stop mode, the impact threshold value used for comparison with the magnitude of acceleration is the third impact threshold value. When the vehicle is stopped, an accident such as a collision with a vehicle on which a bicycle is stopped is assumed, and the magnitude of acceleration caused by such an accident is usually a collision accident during traveling. It is smaller than the magnitude of the acceleration caused by it. For this reason, the third impact threshold value is smaller than the first impact threshold value.

Specifically, the third impact threshold is set to a value that can detect a bicycle collision as described above. For example, the third impact threshold value is set to about 0.05 × 9.8 m / s ² (= 0.05 G) to 0.1 × 9.8 m / s ² (= 0.1 G). The specific value of the third impact threshold is substantially the same as the specific value of the second impact threshold, and the third impact threshold and the second impact threshold may be set to the same value. . If the third impact threshold value and the second impact threshold value are set to the same numerical value, it is not always necessary to distinguish the parking state and the stopped state by the mode setting unit 8.

  Then, at a certain timing T3 when the operation mode is the stop mode, when an acceleration having a magnitude greater than or equal to the third impact threshold is detected due to a bicycle colliding with the vehicle, the main control unit 10 The accident recording data b is recorded in the recording unit 5 by controlling the buffer memory 4 and the recording unit 5.

  The accident record data b is the same as the above-described accident record data a that can be recorded in the recording unit 5 in the traveling mode. That is, the accident record data b includes image data for a predetermined time before timing T3 or for a predetermined time before and after timing T3. More specifically, the image data from a predetermined time before the timing T3 to the timing T3, or the image data from the predetermined time before the timing T3 to the timing T3 and the timing T3 to the predetermined time after the timing T3. Is included in the accident record data b. In addition, at the timing T3, “position information given from a GPS (not shown), time information (including date) given from a clock device (not shown), speed information specifying a vehicle speed given from a speed sensor (not shown), etc.” It may be included in the recording data b. The accident record data b is handled as objective evidence for verifying the cause of the accident.

(Mode setting section)
Next, the following first, second, third, and fourth classification methods will be exemplified as the method for classifying the driving state of the vehicle by the mode setting unit 8.

  First, the first classification method will be described. The mode setting unit 8 adopting the first classification method includes a boarding determination unit (not shown) that determines whether or not there is a person (such as a driver) inside the vehicle. For example, the boarding determination unit determines whether there is a person inside the vehicle based on the video signal from the camera 2 or another camera equivalent to the camera 2. This determination method can be applied when the driver of the vehicle is included in the imaging region of the camera 2 or another camera.

  FIG. 2 is a view showing a shooting area 40 of such a camera 2 or another camera, and corresponds to a view of the driver as viewed from the rear side of the vehicle. The boarding determination unit focuses on the predetermined area 41 in the imaging area 40. The predetermined area 41 includes a captured image corresponding to the head of the driver 43 and the like. The boarding determination unit receives the video signal corresponding to the predetermined area 41 for each frame via the image processing circuit 3, and the pixel data corresponding to the luminance level of the pixel in the predetermined area 41 in the previous frame and the predetermined area 41 in the original frame. The difference value with the pixel data of the inner pixels is calculated one after another for each pixel in the predetermined area 41. A cumulative difference value a is obtained by cumulatively adding the calculated difference values.

  Then, when the obtained accumulated difference value a is continuously below a predetermined threshold for a first predetermined time (for example, several tens of seconds to several minutes) (this condition is hereinafter referred to as “condition 1”), boarding determination The unit determines that there is no driver inside the vehicle. On the other hand, when the condition 1 is not satisfied, the boarding determination unit determines that the driver is inside the vehicle. The driver's body (including the head) usually moves with the driving of the vehicle even though it stops somewhat. The threshold value used for the comparison with the cumulative difference value a is set so that the presence or absence of movement accompanying this driving or the like can be determined.

  As described above, the boarding determination unit according to the first classification method determines whether there is a person inside the vehicle based on the video signal corresponding to the inside of the vehicle photographed by the camera 2 or the other camera. In other words, the boarding determination unit according to the first classification method determines whether there is a person inside the vehicle based on the video signal corresponding to the imaging target located inside the vehicle. When the boarding determination unit determines that there is no person inside the vehicle, the mode setting unit 8 determines that the driving state of the vehicle is in the parking state. On the other hand, when the boarding determination unit determines that there is a driver inside the vehicle, the mode setting unit 8 determines that the driving state of the vehicle is in the running state or the stopped state.

  Next, the second classification method will be described. The mode setting unit 8 adopting the second segmentation method pays attention to the predetermined area 42 in the imaging area 40 of FIG. The predetermined area 42 is an area different from the predetermined area 41, and the predetermined area 42 includes an imaging target located outside the vehicle (for example, a road on the traveling direction side or another vehicle located on the road). The photographed image showing is included. When the second segmentation method is used without using the first segmentation method, it is not always necessary to include the vehicle driver in the imaging region of the camera 2 or another camera.

  The mode setting unit 8 that executes the second segmentation method receives a video signal corresponding to the predetermined area 42 for each frame via the image processing circuit 3, and a pixel corresponding to the luminance level of the pixel in the predetermined area 42 in the previous frame. The difference value between the data and the pixel data of the pixels in the predetermined area 42 in the original frame is successively calculated for each pixel in the predetermined area 42. A cumulative difference value b is obtained by cumulatively adding the calculated difference values.

  When the obtained accumulated difference value b is continuously below a predetermined threshold for a second predetermined time (for example, several tens of seconds to several minutes) (this condition is hereinafter referred to as “condition 2”), mode setting is performed. The part 8 determines that the driving state of the vehicle is not the traveling state (that is, the vehicle is stopped or parked). On the other hand, when the condition 2 is not satisfied, the mode setting unit 8 determines that the driving state of the vehicle is the traveling state. While the vehicle is traveling, the video signal corresponding to the predetermined area 42 usually changes one after another. The threshold value used for the comparison with the cumulative difference value b is set so that the degree of fluctuation of the video signal accompanying this traveling can be determined.

  As described above, the mode setting unit 8 in the second classification method determines whether the driving state of the vehicle is the traveling state based on the video signal corresponding to the outside of the vehicle photographed by the camera 2 (or the other camera). Determine whether. In other words, it can be said that the mode setting unit 8 in the second classification method determines whether or not the driving state of the vehicle is the traveling state based on the video signal corresponding to the imaging target located outside the vehicle. Further, if the first classification method and the second classification method are combined, that is, if attention is paid to both the predetermined area 41 and the predetermined area 42, the driving state of the vehicle is divided into a running state, a parking state, and a stopped state. It is possible to determine.

  Next, the third classification method will be described. The mode setting unit 8 adopting the third classification method determines whether or not the driving state of the vehicle is the traveling state based on the magnitude of the acceleration of the vehicle detected by the acceleration sensor 6. Specifically, when the detected acceleration is continuously below a predetermined threshold for a third predetermined time (for example, several seconds to several tens of seconds) (this condition is hereinafter referred to as “condition 3”), a mode is set. The setting unit 8 determines that the driving state of the vehicle is not the traveling state (that is, the stopped state or the parking state). On the other hand, when the condition 3 is not satisfied, the mode setting unit 8 determines that the driving state of the vehicle is the traveling state. In general, the magnitude of acceleration during travel varies with acceleration and deceleration. The threshold value used for the comparison with the magnitude of the acceleration is set so that the presence or absence of the acceleration fluctuation accompanying the acceleration or deceleration can be determined.

  Next, the fourth classification method will be described. The mode setting unit 8 adopting the fourth classification method determines whether or not the driving state of the vehicle is a parking state based on a measurement result of a weight sensor (not shown) capable of measuring a weight by a person riding in the vehicle. Determine. In other words, the mode setting unit 8 according to the fourth classification method includes a boarding determination unit (not shown) that determines whether there is a person (such as a driver) inside the vehicle based on the measurement result of the weight sensor. It can be said that it is determined whether or not the driving state of the vehicle is the parking state based on the determination result of the boarding determination unit.

  The weight sensor is disposed below the seat of the vehicle or below the floor of the vehicle. Specifically, when the detected weight is continuously below a predetermined threshold for a fourth predetermined time (for example, 1 second to several tens of seconds) (this condition is hereinafter referred to as “condition 4”), a mode setting unit 8 determines that the driving state of the vehicle is a parking state. On the other hand, when the condition 4 is not satisfied, the mode setting unit 8 determines that the driving state of the vehicle is not the parking state (that is, the traveling state or the stopped state). When a person is on the vehicle, the weight according to the weight of the person is naturally measured. The above-mentioned threshold value used for comparison with the measured weight is set so that the presence or absence of the weight accompanying the boarding can be determined. The measurement result of the weight sensor is transmitted to the mode setting unit 8 using wired or wireless communication.

  The above-described first to fourth classification methods can be arbitrarily combined. For example, if all of the first to fourth classification methods are executed and the results are combined to determine the driving state of the vehicle, an improvement in determination accuracy (reduction in erroneous determination) can be expected. Moreover, you may determine whether the driving | running state of a vehicle is a driving | running | working state based on the speed of the vehicle detected by the speed sensor (not shown).

  Regardless of which of the first to fourth classification methods is used, the mode setting unit 8 sets after a predetermined time has elapsed from the time when the vehicle actually travels to the stopped state. The operation mode is shifted from the running mode to the stop mode (that is, the impact threshold value used for comparison with the magnitude of acceleration is changed from the first impact threshold value to the third impact threshold value). In addition, after a predetermined time has elapsed from the time when the vehicle actually travels (or is stopped) to the parked state, the set operation mode is changed from the travel mode (or stop mode). The monitoring mode is entered (that is, the impact threshold value used for comparison with the magnitude of acceleration is changed from the first impact threshold value (or the third impact threshold value) to the second impact threshold value). The time from when the vehicle actually stops until it shifts to the stop mode and the time from when the vehicle actually parks to when it shifts to the parking mode depends on the first to fourth predetermined times.

(Camera control unit)
Next, the operation of the camera control unit 12 will be described. FIG. 3 is a diagram illustrating the configuration of the camera 2 and the camera control unit 12. The camera 2 includes an optical system 21, a diaphragm 22, and an image sensor 23 composed of a CCD or the like. The camera control unit 12 includes a zoom magnification control unit (view angle control unit) 25, a focal length control unit 26, a sensitivity control unit 27, a motion vector detection unit 28, and a camera direction control unit 29.

  The optical system 21 is composed of a plurality of lenses for adjusting zoom magnification and focal length. The zoom magnification of the optical system 21 is controlled by the zoom magnification control unit 25. If the zoom magnification is changed, the angle of view of the camera 2 is also changed accordingly. The angle of view in the traveling mode is normally set to be relatively small so as to increase the resolution by narrowing the imaging target forward. The focal length (focus) of the optical system 21 is controlled by the focal length control unit 26. In the traveling mode, for example, the focal length of the optical system 21 is adjusted so that an imaging target that is several meters to several hundred meters away from the vehicle is in focus.

  The sensitivity control unit 27 controls the size of the opening of the diaphragm 22 in accordance with the amount of light incident on the image sensor 23. If the aperture of the diaphragm 22 becomes large, the amount of incident light to the image sensor 23 increases. That is, the sensitivity of the image sensor 23 (camera 2) is increased. The camera direction control unit 29 can change the orientation of the camera 2 via a drive mechanism (not shown). The camera control unit 12 can further change the frame frequency of the camera 2.

  The camera control unit 12 changes the shooting conditions of the camera 2 (camera orientation, angle of view, focal length, frame frequency, sensitivity, etc.) according to the operation mode set by the mode setting unit 8. First, the change of the direction of the camera 2 by the camera direction control unit 29 will be described. As described above, when the camera 2 is attached to the rear side of a vehicle rear-view mirror (not shown) or the like so that an imaging target in front of the vehicle (traveling direction) can be photographed through a windshield (not shown). think of. In this case, in the travel mode and the stop mode, the orientation of the camera 2 is kept in the normal state. That is, the orientation of the camera 2 is maintained so that the camera 2 can capture an imaging target in front of the vehicle. On the other hand, when the mode is shifted from the travel mode or the like (travel mode or stop mode) to the monitoring mode, the camera direction control unit 29 changes the direction of the camera 2 via a drive mechanism (not shown) so that the camera 2 can capture the inside of the vehicle. For example, it is rotated 180 degrees.

  In addition, the zoom magnification control unit (view angle control unit) 25 controls the view angle of the optical system 21 so that the view angle in the monitoring mode is wider than the view angle in the traveling mode or the like. By controlling the orientation and angle of view of the camera 2 in this manner, a suspicious person who tries to steal an article in the vehicle can be accommodated in the imaging region.

  Further, the focal length control unit 26 controls the focal length of the optical system 21 so that the focal length in the monitoring mode is shorter than the focal length in the traveling mode or the like. More specifically, in the monitoring mode, the focal length of the optical system 21 is controlled so as to focus on the suspicious person as described above.

  Further, while the suspicious action by the suspicious person does not end in an instant like a collision accident, the frame frequency in the monitoring mode is higher than the frame frequency in the running mode in view of the fact that the recording area of the recording unit 5 is limited. The camera control unit 12 controls the image sensor 23 (camera 2) so as to be smaller. Specifically, for example, the frame frequency in the traveling mode or the like is set to 30 frames / second, while the frame frequency in the monitoring mode is set to 1 to 2 frames / second.

  In addition, suspicious people often attempt to steal goods from vehicles when the surroundings are dark. In view of this, the sensitivity control unit 27 may control the diaphragm 22 so that the sensitivity in the monitoring mode is larger than the sensitivity in the traveling mode or the like.

  It should be noted that the above-described change in the orientation of the camera 2 and the angle of view may be executed in any combination. That is, the camera control unit 12 may change at least one of the shooting conditions of the camera 2 in the camera 2, the angle of view, the focal length, the frame frequency, and the sensitivity according to the type of operation mode.

  In addition, at a certain timing T4 when the operation mode is the monitoring mode, when a suspicious person applies vibration or the like to the vehicle, acceleration (abnormal acceleration) having a magnitude greater than or equal to the second impact threshold is detected. The camera direction control unit 29 changes the direction of the camera 2 in accordance with the direction of acceleration at the timing T4. For example, as shown in FIG. 4, it is assumed that a suspicious person 51 approaches the vehicle to which the drive recorder 1 is attached from the left side and pulls the door 52 on the left side of the vehicle in the drawing, thereby causing an abnormal acceleration at timing T4. The direction of acceleration at timing T4 is leftward in the figure. At this time, the camera direction control unit 29 turns the camera 2 toward the suspicious person 51 via a drive mechanism (not shown). That is, the direction of the camera 2 is changed so that the landscape (including the suspicious person 51) on the direction of acceleration at the timing T4 can be photographed. Thereby, the suspicious person 51 comes to be within the imaging region.

(Motion vector control)
In addition, the motion vector detection unit 28 detects a motion vector of an imaging target (for example, a suspicious person as described above) based on the video signal from the camera 2 in the monitoring mode. A known representative point matching method may be used to detect the motion vector. Hereinafter, an example of the configuration of the motion vector detection unit 28 employing the representative point matching method will be described. FIG. 5 shows a shooting area of the camera 2, and nine detection blocks BL1 to BL9 (BL1, BL2, BL3, BL4, BL5, BL6, BL7, BL8, BL9) are provided in this shooting area. ing. Each of the detection blocks BL1 to BL9 is divided into 16 search ranges 61. As shown in an enlarged view in FIG. 6, each search range 61 includes a plurality of sampling points (pixels) 63, and one representative point 62 is determined near the center of each search range 61.

  FIG. 7 is a block diagram showing a configuration of the motion vector detection unit 28. A digital video signal from the camera 2 is supplied to a representative point memory 70 and a correlation value calculation circuit 71. The representative point memory 70 stores pixel data corresponding to the luminance level of each representative point 62. For each search range 61, the correlation value calculation circuit 71 “pixel data of the representative point 62 in the previous frame” and “pixel data of each sampling point 63 in the search range 61 shifted with respect to the representative point 62 of the current frame”. The correlation value (absolute value of the difference) is calculated.

  In each of the detection blocks BL <b> 1 to BL <b> 9, the correlation value corresponding to the sampling point 63 having the same shift with respect to each representative point 62 is cumulatively added by the cumulative addition circuit 72. The motion vector generation unit 73 generates a motion vector based on the position of the sampling point 63 that gives the minimum cumulative correlation value (hereinafter referred to as “minimum position”) among the plurality of cumulative correlation values obtained by this cumulative addition. To do. The motion vector generation unit 73 obtains the minimum position for each of the detection blocks BL1 to BL9, and obtains a motion vector for each of the detection blocks BL1 to BL9. Thus, the pixel data in each search range 61 that is closest to the pixel data of the representative point 62 is detected, and a motion vector is obtained based on this.

  The camera direction control unit 29 changes the direction of the camera 2 according to the motion vector detected as described above in the monitoring mode. At this time, the orientation of the camera 2 may be changed according to the motion vector only after the abnormal acceleration is detected. Further, after the abnormal acceleration is detected at the timing T4 as described above and the direction of the camera 2 is directed toward the suspicious person 51, the direction of the camera 2 is further changed according to the motion vector of the suspicious person 51. May be.

  For example, as shown in FIG. 8, it is assumed that the suspicious person 51 moves to the right side in a state where the suspicious person 51 is photographed in the detection block BL8 at the center on the right side of the photographing region. In FIG. 8, the same parts as those in FIG. 5 are denoted by the same reference numerals. In this case, the motion vector in the detection block BL8 is rightward. If the orientation of the camera 2 is fixed, the suspicious person 51 goes out of the shooting area. At this time, the camera direction control unit 29 causes the suspicious person 51 to be within the shooting area of the camera 2. The direction of the camera 2 is changed according to the rightward motion vector. Specifically, for example, the direction of the camera 2 is changed so that the suspicious person 51 continues to be within the detection block BL8 even though the suspicious person 51 has moved to the right as described above. Alternatively, after changing the orientation of the camera 2 so that the suspicious person 51 falls within the detection block BL5 that is near the center of the shooting area, the suspicious person 51 continues to fall within the detection block BL5 within the shooting area. Change the direction of 2.

  In the state shown in FIG. 8, a rightward motion vector is detected in the detection block BL8, but no motion vector is detected in the other detection blocks BL1 to BL7 and BL9. Using this fact, the angle of view (zoom magnification) of the camera 2 may be changed so that the suspicious person 51 is enlarged and photographed. Specifically, for example, the orientation of the camera 2 is changed and the angle of view of the camera 2 is changed so that the area in the detection block BL8 of FIG. Even after the angle of view is changed, the orientation of the camera 2 may be changed according to the motion vector of the suspicious person 51 (so as to track the suspicious person 51).

  Although the acceleration sensor 6 is operated in all operation modes, the power supply to the camera 2 is cut off when the operation mode shifts from the traveling mode or the stop mode to the monitoring mode for the purpose of power saving or the like. I try to do it. Then, when abnormal acceleration is detected in the monitoring mode, the power supply of the camera 2 is restarted to operate the camera 2, and when a motion vector is detected, a suspicious person or the like having the motion vector is always photographed. To. As with the acceleration sensor 6, the camera 2 (and the entire drive recorder 1 in FIG. 1) may always be operated in all operation modes including the monitoring mode.

  Further, when the timing at which the abnormal acceleration is detected is T2, as described above, “the image data from the timing T2 to a predetermined time after the timing T2 is included in the monitoring record data”, but after detecting the abnormal acceleration, When the motion vector is detected by the motion vector detection unit 28 and the suspicious person 51 having the motion vector is moving in the imaging region, the image data may be continuously recorded in the recording unit 5. At this time, if the notification unit 13 includes the communication circuit as described above, the continuously obtained image data may be transmitted to an external device (such as a computer owned by the user). Good.

(Difference in recording method)
By the way, while it is difficult to think that surveillance record data that can become evidence of theft is altered by a theft victim (vehicle driver or the like), accident record data a and b are altered by the driver of the accident vehicle. There is a fear. In order to investigate the cause of the accident, when the relevant departments (police station, insurance company, drive recorder 1 management company, etc.) are requested to submit the accident record data a and b, the data will be convenient for them. This is because the intention of falsifying can be worked. For this reason, in the drive recorder 1, the recording method of the accident recording data a and b recorded in the traveling mode and the stop mode is different from the recording method of the monitoring recording data recorded in the monitoring mode.

  For example, a tampering prevention processing unit (not shown) that performs encryption processing (falsification prevention processing) on the image data is provided between the buffer memory 4 and the recording unit 5 or in the image processing circuit 3. The operation of the tampering prevention processing unit is controlled by the main control unit 10, and the encryption processing method is changed between the “traveling mode and stop mode” and the “monitoring mode”. Here, the cryptographic processing method is a concept including whether or not cryptographic processing is performed. For example, the monitoring record data recorded in the “monitoring mode” is not subjected to encryption processing, while the accident recording data a and b recorded in the “traveling mode and stop mode” are subjected to encryption processing.

  As this encryption processing, for example, a digital watermark may be used. That is, the tampering prevention processing unit applies digital watermark to the image data recorded as the accident record data a and b. Thereby, falsification of the accident record data a and b is suppressed, and when the falsification has occurred, the fact is specified by the related department (such as a police station). Further, when the notification unit 13 is provided with a communication circuit as described above and the accident record data a and b are transmitted to an external device (such as a computer owned by the user), the accident record data a and b with a digital watermark are provided. (Image data) may be transmitted by a public key cryptosystem or a secret key cryptosystem. As a result, the accident record data a and b can be prevented from being viewed by a third party, and the related department (the police station or the like) can decrypt the first secret key in the public key cryptosystem or the second in the secret key cryptosystem. By performing decryption with the secret key, it is possible to reliably confirm whether or not data that has not been tampered with has been transmitted.

  On the other hand, digital watermarking is not applied to the monitoring record data recorded in the “monitoring mode”. This is because it is more convenient for a user who can be a victim of theft to easily check the video. However, the image data in the monitoring record data may not be browsed unless the password or user ID determined by the user is known. This is also a kind of cryptographic processing. For example, when the recording unit 5 is a portable recording medium such as a memory card, the password set by the user when attempting to view the monitoring recording data recorded on the recording medium with a personal computer or the like Or a user ID may be requested.

  Further, while it is convenient for the user of the drive recorder 1 to be able to freely delete the monitoring record data that is not related to the theft evidence material, the accident record data a and b are stored in the accident vehicle. It is not desirable from the standpoint of investigating the cause of the accident to make it possible to delete it by the driver's discretion.

  Therefore, the main control unit 10 or the tampering prevention processing unit controlled by the main control unit 10 causes the recording unit 5 to record the monitoring record data corresponding to the “monitoring mode” in an erasable format, while the “running mode and stoppage” The accident recording data a and b corresponding to the “mode” are recorded in the recording unit 5 in an erasable format. For example, the monitoring record data is recorded in a format that can be deleted by the user operating the input unit (not shown) of the drive recorder 1 or the input unit (not shown) of the personal computer. The recording data a and b are in a format that cannot be erased by these operations.

  Also, for example, the recording area of the recording unit 5 is divided into an area α that can be erased by the above operation and an area β that cannot be erased, and the monitoring record data is recorded in the area α while the accident record data a and b are recorded in the area A method of recording in β may be adopted.

  Further, the recording area of the recording unit 5 may be physically divided into two. For example, the recording unit 5 is divided into a first recording medium such as a memory card that can be carried and a second recording medium that is fixed in the drive recorder 1 so that the user cannot carry it alone. Then, the accident recording data a and b are recorded on the second recording medium while the monitoring recording data is recorded on the first recording medium.

  The drive recorder according to the present invention can be mounted on various moving bodies in addition to vehicles such as automobiles and motorcycles (so-called motorcycles and electric bicycles).

It is a block diagram which shows the structure of the drive recorder which concerns on embodiment of this invention. It is a figure for demonstrating the classification method of the driving | running state of the vehicle by the mode setting part of FIG. It is a figure which shows the structure of the camera of FIG. 1, and a camera control part. It is a figure showing the condition which a suspicious person gives a vibration to a vehicle. FIG. 4 is a diagram for explaining a representative point matching method performed by a motion vector detection unit in FIG. 3, and is a diagram illustrating an imaging region of the camera in FIG. 1. FIG. 6 is an enlarged view of a certain search range in FIG. 5. It is a figure which shows the structure of the motion vector detection part of FIG. It is a figure for demonstrating operation | movement of the camera control part of FIG.1 and FIG.3, and is a figure showing the condition where the suspicious person is reflected in the imaging | photography area | region of the camera of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drive recorder 2 Camera 3 Image processing circuit 4 Buffer memory 5 Recording part 6 Acceleration sensor 7 Impact detection part 8 Mode setting part 10 Main control part 12 Camera control part 13 Notification part 14 Display apparatus 21 Optical system 22 Aperture 23 Imaging element 25 Zoom Magnification controller (view angle controller)
26 focal length control unit 27 sensitivity control unit 28 motion vector detection unit 29 camera direction control unit 61 search range 62 representative point 63 sampling point 70 representative point memory 71 correlation value calculation circuit 72 cumulative addition circuit 73 motion vector generation unit BL1 to BL9 detection block

Claims (23)

A drive recorder attached to a moving body,
A camera for shooting the imaging target;
A buffer memory for temporarily storing image data corresponding to the video signal from the camera;
A recording unit capable of recording the image data stored in the buffer memory;
A main control unit for controlling the recording operation of the image data by the recording unit based on the magnitude of acceleration of the moving body;
The driving state of the moving body is determined by dividing it into a driving state and a parking / stopping state, and when the determined driving state is the driving state, the operation mode of the drive recorder is set to the driving mode while the determined driving state A mode setting unit that sets the operation mode to the parking / stopping mode when the vehicle is in the parking / stopping state,
The main control unit controls the recording operation based on a comparison result between the magnitude of the acceleration and a predetermined first threshold value in the traveling mode, and the magnitude of the acceleration and the speed in the parking / stopping mode. A drive recorder that controls the recording operation based on a comparison result with a threshold value smaller than the first threshold value. The main control unit causes the recording unit to record data including the image data a predetermined time before the time when the magnitude of the acceleration reaches the first threshold value or more in the traveling mode. The drive recorder according to claim 1. The parking / stopping state is a state including a parking state and a stopping state,
The mode setting unit determines the driving state of the moving body by dividing into a driving state, a parking state, and a stopped state, and sets the operation mode to a monitoring mode when the determined driving state is a parking state. The drive recorder according to claim 1, wherein when the determined driving state is a stop state, the operation mode is set to a stop mode. When the magnitude of the acceleration reaches a second threshold value that is smaller than the first threshold value in the monitoring mode, the main control unit records data including the image data after that point in the recording unit. The drive recorder according to claim 3, wherein: 4. The information processing apparatus according to claim 3, further comprising: a notification unit configured to perform notification according to the acceleration when the magnitude of the acceleration reaches a second threshold value that is smaller than the first threshold value in the monitoring mode. Drive recorder. The drive recorder according to claim 5, wherein the notification unit includes a communication circuit that communicates with an external device, and transmits notification information corresponding to the notification to the external device via the communication circuit. When the operation mode shifts from a mode different from the monitoring mode to the monitoring mode, the power supply to the camera is cut off, but the magnitude of the acceleration has reached the second threshold or more in the monitoring mode. The drive recorder according to any one of claims 3 to 6, wherein power supply to the camera is resumed. The drive recorder according to any one of claims 1 to 7, wherein the mode setting unit performs the classification of the operation state of the moving body based on a video signal from the camera. The mode setting unit includes a boarding determination unit that determines whether there is a person inside the moving body, and determines whether the driving state of the moving body is a parking state based on the determination result. The drive recorder according to any one of claims 3 to 7, wherein The drive recorder according to claim 9, wherein the boarding determination unit determines whether there is a person inside the moving body based on a video signal obtained by photographing the inside of the moving body. The drive recorder further includes another camera for photographing the inside of the moving body,
The drive recorder according to claim 9, wherein the boarding determination unit determines whether there is a person inside the moving body based on a video signal from the other camera. The said boarding determination part determines whether there is a person inside the said moving body based on the measurement result of the weight sensor which can measure the weight by the person inside the said moving body. The described drive recorder. The drive according to any one of claims 1 to 7, wherein the mode setting unit determines whether or not the driving state of the moving body is a running state based on the magnitude of the acceleration. Recorder. 8. The camera control unit according to claim 1, further comprising a camera control unit that changes a shooting condition of the camera according to a type of the operation mode set by the mode setting unit. Drive recorder. 15. The camera control unit changes at least one of the photographing conditions among a camera orientation, a field angle, a focal length, a frame frequency, and a sensitivity according to a type of the operation mode. Drive recorder as described in. The camera further includes a camera direction control unit that changes the direction of the camera according to the direction of the acceleration when the magnitude of the acceleration reaches a second threshold value that is smaller than the first threshold value in the monitoring mode. The drive recorder according to claim 3. A motion vector detection unit that detects a motion vector of the imaging target based on the video signal in the monitoring mode;
The drive recorder according to any one of claims 3 to 7, further comprising a camera direction control unit that changes a direction of the camera in accordance with the detected motion vector. A motion vector detection unit that detects a motion vector of the imaging target based on the video signal in the monitoring mode;
A camera direction control unit that changes a direction of the camera according to the motion vector so that the subject moves within the shooting area of the camera when there is a moving subject having the motion vector in the monitoring mode; 8. The drive recorder according to claim 3, further comprising a drive recorder. 19. The drive recorder according to claim 18, further comprising a zoom magnification control unit that changes an angle of view of the camera so that the subject is photographed in an enlarged manner. The drive recorder according to any one of claims 3 to 7, wherein a recording method of the image data in the recording unit is different between the traveling mode and the monitoring mode. The drive recorder according to claim 20, wherein the recording method is a method of encryption processing for the image data to be recorded in the recording unit. The main control unit causes the recording unit to record the image data in an erasable format in the monitoring mode, and causes the recording unit to record the image data in a non-erasable format in the traveling mode. 21. The drive recorder according to claim 20, wherein 8. The drive recorder according to claim 3, wherein a recording area of the recording unit for recording the image data is made different between the traveling mode and the monitoring mode.

Images