JP3659110B2 - In-vehicle image processing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an in-vehicle image processing apparatus that processes an image signal obtained from an imaging means installed in a vehicle, and more particularly to an in-vehicle image processing apparatus having a self-diagnosis function for determining whether an image signal is normal. Is.
[0002]
[Prior art]
2. Description of the Related Art In recent years, various techniques have been developed to capture the periphery of a vehicle with an imaging means such as a video camera installed in the vehicle, and to process an image signal obtained thereby to reflect it in the traveling of the vehicle. For example, by installing a video camera at the rear of the vehicle and imaging the approaching vehicle on the rear side, a buzzer sounds when the driver operates the turn indicator to change lanes or to turn right or left A system has been proposed to alert the driver.
[0003]
In this type of system, for example, when the image output line of the video camera is cut for some reason, both the image signal and the synchronization signal output from the video camera are interrupted. Therefore, it is possible to detect the disconnection of the image output line by self-diagnosis on the controller side that performs image processing.
[0004]
[Problems to be solved by the invention]
However, for example, when an imaging unit such as a CCD of a video camera fails, a situation occurs in which an image signal is not output from the video camera although a synchronization signal is output. The situation where the image signal is not output is equivalent to the case where the darkness is taken from the level of the image signal. Therefore, as long as the synchronization signal is output, there is a problem that even if a situation in which an image signal is not output occurs, this type of abnormal situation cannot be detected by self-diagnosis on the controller side.
[0005]
On the other hand, Japanese Patent Laid-Open No. 9-113221 discloses a technique for detecting whether or not a captured image is normal, but this technique calculates the amount of edge of an image and compares it with a reference value. By doing so, the abnormality of the image is detected, and there is a problem that the detection procedure is complicated.
[0006]
Accordingly, an object of the present invention is to provide an in-vehicle image processing apparatus capable of easily detecting an abnormality of an image signal obtained from an imaging means installed in a vehicle.
[0007]
[Means for Solving the Problems]
The object is to determine whether or not the image signal is abnormal based on the image processing means for processing the image signal obtained from the imaging means installed in the vehicle and the brightness of the vehicle speed and the surroundings of the vehicle. This is achieved by an in-vehicle image processing apparatus including a determination unit that outputs a signal. Preferably, the determination means abnormally detects the image signal when the level of the image signal is equal to or lower than a predetermined value and the vehicle speed and the brightness around the vehicle are equal to or higher than a predetermined value for a predetermined time. Is determined.
[0008]
Here, the brightness around the vehicle can be determined by, for example, whether or not the headlamp is lit. This is because it is possible to estimate that the situation in which the headlamp is OFF and the vehicle can travel at a predetermined speed or more for a predetermined time is not nighttime. As a result, the level of the image signal is below the predetermined value in such a situation. This is because it is determined that the image signal is not abnormal because the image is dark. You may judge by the lighting condition of a clearance lamp instead of a headlamp. Whether the headlamp or the clearance lamp is lit can be detected by a signal from a lamp switch that is linked to these operations. Alternatively, the brightness around the vehicle may be detected by measuring the light intensity and illuminance with a photometer or illuminometer.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a conceptual diagram showing an example of a vehicle equipped with an in-vehicle image processing apparatus according to the present invention. As shown in the figure, an image display device 2 for displaying various images such as navigation information is disposed in the front part of the vehicle 1 and a lamp switch 4 is provided in the vicinity of the handle 3. When the lamp switch 4 is operated, a signal indicating that the head lamp or the clearance lamp is turned on according to the operation position is output.
[0010]
On the other hand, a video camera 5 is provided at the rear of the vehicle. The video camera 5 captures the rear of the vehicle and continuously outputs an image signal with a synchronization signal. This image signal is used, for example, when the rear side monitoring function or the rear view monitoring function is activated. Here, the rear side monitoring function is a function that determines the approaching vehicle on the rear side, emits a buzzer sound from the alarm means 8 when operating the direction indicator, and alerts the driver, and the rear view monitor function. This is a function for displaying the rear video camera image on the image display device 2 when the shift lever is put in the back range.
[0011]
A vehicle speed sensor 6 is attached to a transmission (not shown) to detect the vehicle speed. Signals from the lamp switch 4, the video camera 5 and the vehicle speed sensor 6 and signals from various sensors (not shown) are input to the controller 7.
[0012]
The controller 7 processes these signals and displays a desired image on the image display device 2 as necessary. As will be described later, the controller 7 determines normality / abnormality of the input image signal. When it is determined that the image signal is abnormal, the controller 7 stops using the image signal, and the alarm means 8 issues an alarm. Is generated. The alarm means 8 is provided, for example, on an instrument panel, and notifies the driver of an abnormality in the image signal by lighting or blinking of an alarm lamp, or by an alarm sound or sound.
[0013]
FIG. 2 is a block diagram showing an embodiment of the in-vehicle image processing apparatus according to the present invention. As illustrated, the controller 7 includes an image memory 71 that stores an image signal input from the video camera 5, an image processing device 72 that processes an image signal obtained via the image memory 71, a vehicle speed sensor 6, and a lamp switch. (SW) Whether the image signal is abnormal based on the input processing means 73 for processing the input signal from the image signal 4 and the vehicle speed and illuminance obtained via the input processing means 73 and the image signal obtained via the image memory 71 The determination means 74 which determines whether is provided. A signal from the image processing device 72 is displayed on the image display device 2 when the above-described rear view monitor function is activated. Further, when the rear side monitoring function is activated, a buzzer sound is emitted from the alarm means 8 based on a signal from the image processing device 72.
Further, when the determination unit 74 determines that the image signal is abnormal, a signal is output to the image processing device 72 to stop using the image signal, and an alarm is issued in the alarm unit 8. As described above, alarms that appeal to sight such as lamps or those that appeal to hearing such as electronic sounds and voices are preferably used as described above.
[0014]
FIG. 3 is a flowchart showing a procedure for determining an abnormality of the image signal in the determination unit 74. As shown in the figure, the determination means 74 first determines in step 31 whether the level of the image signal is equal to or lower than a predetermined value. The predetermined value is, for example, a level at which the image signal almost outputs a black screen, but is not limited to this value. By setting in this way, the level of the image signal becomes equal to or lower than the predetermined value when the image signal is an image of complete darkness or when some abnormality occurs and no image signal is output. If it is determined in step 31 that the level of the image signal exceeds the predetermined value, it is determined that the image signal is normal, and the process returns to the beginning of this flowchart.
[0015]
On the other hand, if it is determined that the level of the image signal is equal to or lower than the predetermined value, it is determined in the next step 32 whether the vehicle speed is equal to or higher than the predetermined value. The predetermined value is, for example, 30 km / h, but is not limited thereto, and may be a value indicating that the vehicle is traveling. If it is determined in step 32 that the vehicle speed is less than the predetermined value, it may be considered that the vehicle is not running, and the process returns to the beginning of this flowchart.
[0016]
If it is determined that the vehicle speed is equal to or higher than the predetermined value, it is determined in the next step 33 whether the headlamp is OFF. Whether the headlamp is OFF is determined by a signal from the lamp switch 4. It can also be determined by whether the small lamp is OFF instead of the headlamp. This is because it is sufficient to identify whether the function of step 33 is daytime. Furthermore, a photometer or illuminometer may be provided separately in the vehicle to detect the light intensity and illuminance around the vehicle, thereby detecting whether it is daytime. If it is determined in step 33 that the headlamp is not OFF, the vehicle is considered to be traveling at night with the headlamp turned on, and the flow returns to the beginning of this flowchart.
[0017]
If it is determined that the headlamp is OFF, in the next step 34, it is determined whether or not a certain time has passed in the state where the headlamp is OFF. The predetermined time is, for example, 15 minutes, but is not limited to this, and may be longer or shorter. If it is determined in step 34 that the predetermined time has not elapsed, the process returns to the beginning of this flowchart.
[0018]
On the other hand, when a predetermined time has elapsed in step 34, it is determined in step 35 that the image signal is abnormal. This is because it is possible to estimate that the situation where the headlamp is OFF and the vehicle can travel at a predetermined speed or more for a predetermined time is not nighttime. As a result, in such a situation, the level of the image signal is below a predetermined value. This is because it can be determined that the image signal is abnormal, not because the image is dark.
Such an operation of the determination means 74 can be performed at all times, but may be repeated every certain period.
[0019]
A video camera mounted on a vehicle is exposed to a harsh environment such as vibration and temperature / humidity changes caused by the vehicle. It is important for various systems that use an image signal captured by the video camera to detect a failure of the video camera in which the image signal itself becomes abnormal by self-diagnosis. This is because if the image signal abnormality is missed, the entire system is adversely affected. According to the present invention, it is possible to suitably prevent a system failure caused by an abnormality in an image signal.
[0020]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the vehicle-mounted image processing apparatus which can detect easily abnormality of the image signal obtained from the imaging means installed in the vehicle can be obtained.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing an example of a vehicle equipped with an in-vehicle image processing apparatus according to the present invention.
FIG. 2 is a block diagram showing an embodiment of an in-vehicle image processing apparatus according to the present invention.
FIG. 3 is a flowchart showing an abnormality determination procedure of an image signal in a determination unit.
[Explanation of symbols]
1 Vehicle 2 Image display device 3 Handle 4 Lamp switch (SW)
5 Video camera 6 Vehicle speed sensor 7 Controller 8 Alarm means 71 Image memory 72 Image processing means 73 Input processing means 74 Determination means

Claims (2)

An image processing unit that processes an image signal obtained from an imaging unit installed in a vehicle, and determines whether the image signal is abnormal based on vehicle speed and brightness around the vehicle, and outputs a warning signal when the abnormality is determined An in-vehicle image processing apparatus comprising: a determination unit. The determination means determines that the image signal is abnormal when the level of the image signal is equal to or lower than a predetermined value and the vehicle speed and the brightness around the vehicle are equal to or higher than a predetermined value for a predetermined time. The in-vehicle image processing apparatus according to claim 1.

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