JP5179750B2 - Drive recorder and photographing method thereof - Google Patents

Description

  The present invention relates to a vehicle-mounted drive recorder having at least a camera for performing fact analysis relating to driving conditions such as vehicle behavior, ambient conditions, and operating conditions, and a method for photographing the same.

  2. Description of the Related Art In recent years, image recording type drive recorders that record images of the moment of an accident or a near-miss or before and after that have been provided.

Specifically, this type of drive recorder, for example, with a CMOS camera, shoots at a frame rate of 30 fps and temporarily records it in a buffer memory. If there is an accident shock or sudden acceleration / deceleration on a drive recorder equipped vehicle, As a trigger, an image of about several tens of seconds before and after that point is recorded on a memory card, and the recorded image can be reproduced by an external device or the like (Patent Document 1).
JP 2006-235732 A

  However, in the “LED (light-emitting diode) type traffic light”, unlike the conventional “bulb-type traffic light”, the LED element as the light emitting unit is 120 per second in the 60 Hz region, unlike when the light bulb-type traffic light is continuously emitted. In the 50 Hz region, the blinking is repeated 100 times per second. For this reason, when the blinking of the LED element and the timing of shooting are synchronized, there is a case where the signal lamp that is lit is shot as if the drive recorder is turned off.

  In such a case, it is impossible to determine the signal light when an accident or near-miss occurs, resulting in trouble in determining responsibility in accident processing.

  Therefore, conventionally, as a method for avoiding such a problem, “a method for avoiding synchronization with blinking of the LED element by changing the imaging frequency” has been considered.

  In this case, the state where no image is captured can be resolved. For example, even if an LED traffic light operating with a 60 Hz power source is photographed at a photographing cycle of 29.5 Hz when lit, the traffic light reflected in the image will continue to blink. As a result, a situation occurs in which several images are not captured continuously.

  In addition, for example, “a method of setting the shutter speed of the drive recorder camera to a shutter speed longer than one cycle of blinking of the LED element (for example, in the case of 50 Hz, slower than 1/100 second)” can be considered. If the LED element is in a lit state, the “bright” state of the LED element is always captured within the exposure time of each frame, so that it may be possible to reliably determine whether or not the LED element is lit. However, at a shutter speed of about 1/100 second, a fast subject becomes a blurred image, and it may be difficult to analyze an accident based on the image and determine responsibility in accident processing. Further, when it is bright as in the daytime, it is overexposed and the same problem occurs.

  The present invention has been made paying attention to such a problem, and its main purpose is to make it difficult to be affected by the blinking cycle when a lighting device such as an LED traffic light is turned on. An object of the present invention is to provide a drive recorder that can suitably check whether there is any.

  In order to achieve this object, the present invention takes the following measures.

  In other words, the drive recorder according to the present invention blinks at an adjacent sampling interval between an imaging unit for mounting on a vehicle and photographing a driving situation, and a sampling interval for continuously capturing a plurality of image data from the imaging unit. And a data fetching unit that controls differently based on the lighting time or lighting time of the lighting device, and fetches and records image data at a sampling timing determined by the controlled sampling interval.

  If this is the case, since it is different based on the lighting time or blinking time of the lighting device that blinks at adjacent sampling intervals, any one sampling interval matches the blinking cycle of the lighting device, Even when an image of the lighting device is in the blinking state is captured at the sampling timing determined by the sampling interval, the adjacent sampling interval does not coincide with the blinking cycle of the lighting device due to the time difference, and is determined by the adjacent sampling interval. At the sampling timing, a bright image of the lighting device can be captured.

  Therefore, it becomes difficult to be affected by the blinking cycle when a lighting device such as an LED traffic light is turned on, and it can be confirmed from the recorded image data whether it is in a lighting state or a light-off state.

  For example, if the sampling interval is not repeated twice so as not to have the same time length, there is no inconvenience that several consecutive images are not captured. In addition, since the image capture time (exposure time) does not have to be increased, there is no problem of subject blurring or overexposure.

  Therefore, accident analysis based on the photographed image can be performed more reliably for responsibility determination in accident processing.

  As a desirable mode of the present invention, there is one in which a predetermined sampling interval appears regularly in a sampling interval sequence in which the controlled sampling intervals are arranged in time series. For example, if the first sampling interval and the second sampling interval having different time lengths appear alternately in the sampling interval row, the blinking state is continued with respect to the blinking cycle of the lighting device. And the lighting state of the lighting device can be confirmed by one of the two consecutive images.

  If the average value of the first sampling interval and the second sampling interval is a period in which a predetermined frame can be captured per second, for example, it can be made to coincide with the time axis of conventional image analysis software. Therefore, each image can be displayed while corresponding to each frame, and image browsing and temporal analysis can be suitably performed.

  Since any one of the controlled adjacent sampling intervals does not fall within the time range determined by the time obtained by moving the blinking time around the time that is an integral multiple of the blinking cycle of the lighting device. If so, it is possible to avoid the problem that all the sampling timings are lost.

  As described above, according to the present invention, the adjacent sampling intervals are different based on the lighting time or the blinking time of the blinking lighting device. Therefore, in the sampling timing determined by one sampling interval among the adjacent sampling intervals. Even if the image of the lit state of the lighting device is captured, the image of the lit state of the lighting device can be captured at the sampling timing determined by the other sampling interval. It becomes difficult to be influenced by the period, and it can be confirmed from the recorded image data whether it is in the lit state or the unlit state.

  Then, if the sampling interval is not repeated twice to avoid the same time length, there is no problem that a situation where several images are not captured continuously occurs. Further, since it is not necessary to slow down the shutter speed, there is no problem of subject blurring or overexposure.

  Therefore, accident analysis based on the photographed image and responsibility determination in accident processing can be performed more reliably.

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

  As shown in FIGS. 1, 2, 3, and 4, the drive recorder 1 according to the present embodiment is a vehicle that records the behavior of the vehicle V, the surrounding conditions, and the like during a certain period before and after an accident or near accident. In a single casing 2 which is of a mounting type and has an overall oval shape, basic components, that is, detection means 3, notification means 4, input means 5, communication means 6, detachable recording means 7 , The information processing means 8 and the like are integrated. The drive recorder 1 has a mounting adapter AP (a device-side mounting portion AP1 (see FIG. 3) fixed to the casing 2) and a windshield V1 fixed to the windshield V1 and slide-engaged with the device-side mounting portion AP1. A portion AP2 (not shown) is used to be detachably attached to the windshield V1. Hereinafter, each part is demonstrated concretely.

  The detection means 3 senses a state related to the behavior of the vehicle V, the surrounding situation, and the like, and outputs state data indicating the state. Here, the camera 31, the acceleration sensor 32, and the position sensor 33 as imaging means. At least three of these are used.

  As shown in FIG. 3 and the like, the camera 31 is, for example, a CCD camera that captures a situation outside the vehicle and outputs state data (image data) indicating the image.

  Although the acceleration sensor 32 is built in the casing 2 and is not shown in FIGS. 1 to 3, the acceleration sensor 32 is configured using, for example, a piezoresistive effect, and is one to three dimensions (for example, acting on the automobile V) If it is three-dimensional, it senses acceleration in the front-rear, left-right, and vertical directions, and outputs state data (acceleration data) indicating the acceleration.

  The position sensor 33 is a GPS receiver that, for example, catches radio waves from a plurality of satellites, senses the position of the vehicle V, and outputs state data (position data) indicating the position, as shown in FIG. The status data includes vehicle speed data transmitted from the vehicle speed sensor of the automobile V, door opening / closing data indicating opening / closing of the door, and the like, which are received via the connector CN. The connector CN is also used for a power source.

  As shown in FIG. 2, the notification unit 4 includes an LED 41 that is a light emitter exposed on the surface of the casing 2, an audio output body (not shown) such as a buzzer or a speaker built in the casing 2, and the like.

  The input means 5 is a button switch provided on the surface of the casing 2 here, as shown in FIG.

  Although the communication means 6 is built in the casing 2, it is not shown in FIGS. 1 to 3, but is hardware for wireless communication that transmits and receives radio waves with a base station and the like.

  Here, the detachable recording means 7 is a CF memory card that is detachably attached to a slot 2 </ b> S that opens to the side of the casing 2.

  As shown in FIG. 4, the information processing means 8 is a so-called computer circuit having a CPU 81, an internal memory 82 (for example, a non-volatile memory), an I / O buffer circuit (which may include an AD converter or the like) 83, and the like. Yes, it is built in the casing 2. Then, when the CPU 81 operates in accordance with a program stored in a predetermined area of the internal memory 82, the information processing means 8 has a data fetch unit 8a, a temporary data storage unit 8b, a data write unit as shown in FIG. 8c, a data transmission unit 8d, a data management unit 8e, and the like are configured to exhibit functions. Hereinafter, each part will be described in detail.

  The data fetching unit 8a continuously records various state data such as traveling, that is, acceleration data, position data, image data, and the like in the temporary data storage unit 8b one after another. In this embodiment, as shown in FIG. 6, the image data of the state data is changed between the first sampling interval A and the second sampling interval B having different time lengths (that is, the sampling interval sequence is set to ABABAB · ..) and is recorded in the temporary data storage unit 8b. Then, by setting the first sampling interval A to 36 msec and the second sampling interval B to 30 msec, these average values (30 msec) coincide with the cycle (30 fps) at which 30 frames can be captured per second. .

  The temporary data storage unit 8b stores at least temporarily the state data acquired by the data acquisition unit 8a, and is formed in a predetermined area in the internal memory 82.

  The data writing unit 8c, when an event indicating an impact of an accident or occurrence of an abnormality occurs, triggers the event data from the temporary data storage unit 8b to the detachable recording unit 7 over a certain period of time. It is transferred and recorded.

  In addition, “when an event indicating an impact of an accident or occurrence of an abnormality occurs” means that the acceleration (deceleration) indicated by the acceleration data exceeds a predetermined reference value, or if the time continues for a certain time or more, Corresponds to the case where the vehicle V is turned off or the like.

  In this embodiment, depending on the event that occurred, it is triggered only when the vehicle speed is higher than the upper limit speed, when the vehicle speed is lower than the acceleration / deceleration, or when some other conditions such as the presence or absence of a brake are met. As described above, data recording is performed to save data to be recorded.

  The detachable recording means 7 that records the state data in this way is extracted from the slot 2S and carried to, for example, an analysis center and used for subsequent analysis.

  The data transmission unit 8d reads, for example, the state data stored in the temporary data storage unit 8b and transmits it to, for example, an analysis center (not shown). In addition, as shown by a broken line in FIG. 5, the data stored in the removable recording means 7 can be read and transmitted.

  The data management unit 8e weights the status data recorded in the temporary data storage unit 8b from the situation at the time of recording, and classifies the status data according to the importance to be recorded. Then, when the memory capacity becomes full or the like, management is performed such that new status data is recorded after being deleted from the less important ones. Note that, as indicated by a one-dot broken line in FIG. 5, the status data recorded in the detachable recording means 7 can be classified in the same manner.

  The image data capturing operation of the drive recorder 1 configured as described above will be described with reference to FIG.

Here, an LED traffic light (not shown) is supplied with 60 Hz power, and blinks 120 times per second, that is, the LED element which is a light-emitting unit flickers cycle T _LED = 8.33 msec (light time T1 = 5.33 msec, blink time) It is assumed that blinking is repeated at T2 = 3 msec), and the image data capture time (exposure time) is shorter than the blink time T2 (for example, about 1/4 of the blink time T2).

When capturing 30 images data p1~p30 per second, the sampling timing of the image data p1, as shown in FIG. 6, enters the blinking state in synchronism with the blinking period _{T LED} of the LED elements, blinking of the LED traffic signal Even when the image data in the state is captured, the sampling timing of the next image data p2 enters the bright state, so that the image data in the bright state of the LED traffic light can be captured.

  Then, at the sampling timing of the next image data p3, the average value (30 msec) of the first sampling interval A and the second sampling interval B is made to coincide with the cycle (30 fps) at which 30 frames can be captured per second. Therefore, the image data in the dark state of the LED traffic light is captured, but the image data in the bright state of the LED traffic light can be captured at the sampling timing of the next image data.

  As described above, since the first sampling interval A and the second sampling interval B having different time lengths appear alternately in the sampling interval sequence, it is possible to continuously capture the extinction state of the LED traffic light. The lighting state of the LED traffic light can be confirmed by any one of two consecutive images.

  In addition, since the image data capture time (exposure time) can be shortened to about 1 msec, there is no problem of blurring of the subject (for example, the opponent vehicle) or overexposure.

  That is, according to the drive recorder 1 configured as described above, it is possible to perform accident analysis based on the photographed image and more reliably perform responsibility determination in accident processing.

  The present invention is not limited to the above embodiment.

For example, as in the above-described embodiment, when the image data capturing time (exposure time) is shorter than the extinction time T2 (for example, about 1/4 of the extinction time T2), the sampling timing ST1 of the image data is There are a case where the start is made before the dead time T2 (for example, FIG. 7) and a case where the start is made from the back (for example, FIG. 8). Then, when the sampling interval sequence ααα... Is synchronized with the blinking cycle T _LED , all the captured image data is in the blinking state.

In such a case, one or more sampling intervals in the sampling interval sequence ααα... Satisfy the average value of the time length of α and the time length of β−the time length of β | In addition, if the sampling timing by β is changed to β that does not fall within the time range determined by the integral multiple of the blinking cycle T _LED ± the blinking time T2, it is possible to capture an image in a bright state on one of the adjacent α and β. As a result, it is possible to avoid such a problem that a corrupted image is captured at every sampling timing.

That is, in the data acquisition unit 8a, the difference between the average value of the sampling intervals and the one sampling interval is equal to or longer than the dead time T2 in the adjacent sampling intervals, and any of the controlled sampling intervals is the blink cycle T _LED lighting machine dark time T2 controlled not enter the time range determined by the time obtained by the front and rear about the integral multiple the time, captured image data at the sampling timing determined by the control sampling interval If one of the sampling intervals coincides with the blinking cycle of the LED traffic light and the image of the blinking state of the LED traffic light is captured at the sampling timing determined by the sampling interval, the time difference is recorded. Therefore, the sampling interval next to it must match the blinking cycle of the LED traffic light. Instead, at the sampling timing determined by the adjacent sampling interval, a bright image of the LED traffic light can be captured.

  Therefore, it becomes difficult to be affected by the blinking cycle when the LED traffic light is turned on, and it can be confirmed from the recorded image data whether the light is on or off.

  Specific examples of sampling interval sequences that can exhibit such effects include αβααα..., Αβααα..., Ααββααα.

  Further, a predetermined sampling interval may be regularly displayed in the sampling interval column. Specific examples of this sampling interval sequence include αβαββαβββ..., Αββγαββγ, etc. (same as above in parentheses).

  In this way, if α that is a predetermined sampling interval appears regularly (periodically) in the sampling interval sequence, system design relating to image capture timing and the like can be performed based on α, and regular ( System design is easier to perform than those that do not appear periodically.

  In addition, the “dead time” in the present invention is not only the time when the light emitting part of the lighting device such as the LED traffic light is turned off, but also when the image is taken with the drive recorder because the light amount from the light emitting part is very small. It also includes the time when the image appears in the off state.

  In the present embodiment, the data acquisition unit 8a controls the time difference between the adjacent sampling intervals to be greater than or equal to the decay time T2. However, the larger the time difference is, the better. It is desirable that the time is not longer than a time that results in a smooth moving image when two frames are forwarded, and that the captured image (amount of light) is less than or equal to the amount that can be processed by the CPU.

  Further, the time length of the sampling interval can be appropriately changed according to the embodiment.

  The number of frames captured per second can be changed as appropriate. Needless to say, animation can be analyzed by increasing the number of captures per unit time.

  The lighting device is not limited to the LED traffic light, and may be, for example, an LED type blinker.

  Other configurations can be variously modified without departing from the spirit of the present invention.

The typical front view showing the case where a drive recorder is attached to the car with the fixture concerning one embodiment of the present invention. The perspective view at the time of seeing from the vehicle inside of the drive recorder in the embodiment. The perspective view at the time of seeing from the vehicle outer side of the drive recorder in the embodiment. The equipment block diagram of the drive recorder in the embodiment. The function block diagram of the information processing means in the embodiment. The chart which shows the sampling timing of the data acquisition in the embodiment. The figure for demonstrating the data acquisition in other embodiment of this invention. The figure for demonstrating the data acquisition in other embodiment of this invention.

Explanation of symbols

V ... Automobile (vehicle)
DESCRIPTION OF SYMBOLS 1 ... Drive recorder 8a ... Data taking-in part 31 ... Imaging means (camera)

Claims (5)

A single imaging means for mounting on a vehicle and photographing the driving situation;
Sampling timing that is determined by controlling the sampling interval in which a plurality of image data is continuously taken in from the imaging unit, and the sampling interval is controlled to be different based on the lighting time or blinking time of the lighting device that blinks at adjacent sampling intervals. A data capture unit that captures and records image data at
A drive recorder characterized in that a predetermined sampling interval appears regularly in a sampling interval sequence in which the controlled sampling intervals are arranged in time series.   2. The drive recorder according to claim 1, wherein a first sampling interval and a second sampling interval having different time lengths appear alternately in the sampling interval sequence.   3. The drive recorder according to claim 2, wherein an average value of the first sampling interval and the second sampling interval is a cycle in which a predetermined frame can be captured per second.   Any one of the controlled adjacent sampling intervals is prevented from entering a time range determined by a time obtained by moving the blinking time around the time that is an integral multiple of a blinking cycle of the lighting device. Item 4. The drive recorder according to any one of Items 1 to 3. The sampling interval for continuously capturing multiple image data from a single camera for shooting the driving situation attached to the vehicle is different between adjacent sampling intervals based on the lighting time or lighting time of the blinking lighting device Control and capture and record image data at a sampling timing determined by the controlled sampling interval, and within the sampling interval sequence in which the controlled sampling intervals are arranged in time series, a predetermined sampling interval is regularly A drive recorder photographing method characterized in that it appears.