JPWO2015083640A1 - Monitoring device - Google Patents

Abstract

Problem: The present invention provides a monitoring device including a camera and a recording device mounted on a vehicle, wherein the exposure time of the camera can be controlled according to the moving speed of the vehicle, and the recording device associates the video data of the camera with the position information of the vehicle. The video data stored in the recording device can be searched based on vehicle position information. Solution: A monitoring apparatus according to the present invention includes an image pickup means installed in a vehicle, an exposure control means for controlling an exposure time of the image pickup means, a vehicle position detection means, and position information detected by the vehicle position detection means. Vehicle speed detection means for detecting the vehicle speed is provided, and the exposure control means controls the exposure time of the imaging means in accordance with the vehicle speed detected by the vehicle speed detection means.

Description

  The present invention relates to a monitoring device, and more particularly to a monitoring device installed in a vehicle.

  Conventionally, when a monitoring device is installed and operated in a vehicle, an afterimage may occur depending on the vehicle speed and the shutter speed (exposure time) of the camera. When capturing a moving subject at high speed, it is common to capture with a reduced shutter speed to suppress afterimages, but the image becomes darker as the shutter speed decreases. On the other hand, functions for correcting the brightness of video include amplification processing and storage processing of video signals. Amplification is a function to increase the brightness of the video by multiplying the video signal, and no noise occurs but noise increases. The accumulation process is a function of increasing the brightness by adding a plurality of images or lengthening the exposure time. Noise is reduced but an afterimage is likely to occur. If you want to suppress afterimages, shorten the shutter speed and do not use the storage function. When a camera is installed on a vehicle that moves at high speed and the outdoors is photographed, the shutter speed is shortened to suppress afterimages. Since the image becomes darker as the shutter speed becomes shorter, the amplification function is used to brighten the image. On the other hand, when the vehicle is stopped or moving at a low speed, it is not necessary to shorten the shutter speed because the subject is at a low speed and the need for suppressing afterimages is low compared to when traveling.

  As another prior art, for example, Patent Document 1 discloses a plurality of network cameras that monitor the inside of a train, a device that records video from the network camera, a display device that displays video, and a vehicle management system. In a system composed of a system control device that controls the entire monitoring system having a communication function with the network, and a network that connects them, by duplicating the system control device and the vehicle management system, A technology having a function of connecting and restoring different vehicle management systems is disclosed.

JP 2012-85158 A

  According to the present invention, in a monitoring device including a camera mounted on a vehicle and a recording device, the exposure time of the camera can be controlled according to the moving speed of the vehicle, and the recording device stores the video data of the camera and the positional information of the vehicle in association with each other. The video data stored in the recording device can be searched based on vehicle position information.

  The monitoring apparatus according to the present invention is based on an image pickup means installed in a vehicle, an exposure control means for controlling an exposure time of the image pickup means, a vehicle position detection means, and position information detected by the vehicle position detection means. Vehicle speed detecting means for detecting the speed is provided, and the exposure control means controls the exposure time of the imaging means according to the vehicle speed detected by the vehicle speed detecting means.

  The monitoring device of the present invention includes a plurality of imaging means installed in a vehicle, display means, display control means for controlling a signal displayed on the display means, vehicle position detection means, and the vehicle position detection means. Vehicle speed detection means for detecting the vehicle speed based on the position information detected in step (b), and the display control means selects an imaging means output to be displayed according to the vehicle speed detected by the vehicle speed detection means, or outputs a plurality of imaging means outputs. The combination is controlled.

  Furthermore, the monitoring apparatus of the present invention includes an imaging unit installed in the vehicle, a vehicle position detection unit, a recording unit, and a search unit that searches the storage unit of the storage unit, and the imaging unit captures an image with the imaging unit. The video data and the position information detected by the vehicle position detection means are associated and output as video information, the recording means records the video information, and the search means searches the video data stored in the storage means based on the position information. Features.

  According to the present invention, in a monitoring device including a camera mounted on a vehicle and a recording device, the exposure time of the camera can be controlled according to the moving speed of the vehicle, and the recording device associates the video data of the camera with the position information of the vehicle. The video data stored in the recording device can be searched based on vehicle position information.

It is a block diagram for demonstrating the monitoring apparatus which is one Example of this invention. It is a sequence diagram for demonstrating vehicle information data communication of the monitoring apparatus which is one Example of this invention. It is a figure for demonstrating the vehicle information data structural example of the monitoring apparatus which is one Example of this invention. It is a flowchart for demonstrating shutter speed control of the camera according to the vehicle speed information of the monitoring apparatus which is one Example of this invention. It is a figure for demonstrating shutter speed control of a camera. It is a block diagram for demonstrating the display switching of the monitoring apparatus which is one Example of this invention. It is a figure for demonstrating the display switching of the monitor of the monitoring apparatus which is one Example of this invention. It is a flowchart figure for demonstrating the monitoring screen switching control according to the vehicle speed information of the monitoring apparatus which is one Example of this invention. It is a flowchart for demonstrating the procedure which detects video data from the positional information of the monitoring apparatus which is one Example of this invention. It is a flowchart for demonstrating an example of the determination method whether the GPS information of the monitoring apparatus which is one Example of this invention and the positional information in video information correspond.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram for explaining a monitoring apparatus according to an embodiment of the present invention.
FIG. 1 shows a monitoring device installed in a vehicle 101. The monitoring apparatus includes cameras 104 and 105 that are imaging means having a distribution function to the network 103, a WEB decoder 106 that demodulates video information distributed via the network 103 into video data that can be displayed on the monitor 107, and via the network 103. A video recording device 109 for storing video information distributed in the network, a console PC 110 for controlling each device connected to the network 103, a position information detection device 108 such as a GPS (Global Positioning System), and a control unit 102. I have. 1 may be divided for each function, or a plurality of functions may be combined into one.

  The control unit 102 acquires position information from the position information detection device 108 and transmits the position information from the data transmission unit 203 to the cameras 104 and 105 via the network 103. Further, the control unit 102 calculates the vehicle moving speed from at least two pieces of position information output from the position information detection device 108 within a predetermined time. The console PC 110 performs control for searching or reproducing the video information stored in the recording device 109.

Next, transmission / reception of vehicle information will be described with reference to FIG.
FIG. 2 is a sequence diagram for explaining vehicle information data communication of the monitoring apparatus according to the embodiment of the present invention.
In FIG. 2, vehicle information 205 is periodically distributed to the data reception unit 204 as multicast packets 206 to 209 at intervals of Δt from the data transmission unit 203 which is a partial function of the control unit 102. The data receiving unit 204 receives the multicast packets 206 to 209 and acquires vehicle information. The data receiving unit 204 is a partial function of the cameras 104 and 105, the WEB decoder 106, and the video recording device 109.

Next, a vehicle information data structure example will be described with reference to FIG.
FIG. 3 is a diagram for explaining an example of the vehicle information data structure of the monitoring apparatus according to the embodiment of the present invention.
In FIG. 3, the vehicle information data is composed of 16 bytes, the first 6 bytes are the system time 301, the next 4 bytes are the longitude information 302, and the next 4 bytes. Is the history information (Latitude) 303, and the next one byte is the vehicle speed information (Speed) 304.
If vehicle information data can be transmitted and received, other communication protocols such as TCP (Transmission Control Protocol) and HTTP (HyperText Transfer Protocol) may be used.

Next, the operation of controlling the shutter speed, which is the exposure time of the camera 104, will be described with reference to FIG.
In addition, the camera 104 is an Example which image | photographs the advancing direction from the head vehicle.
FIG. 4 is a flowchart for explaining the shutter speed control of the camera according to the vehicle speed information of the monitoring apparatus according to the embodiment of the present invention.
The control unit 102 according to one embodiment of the present invention periodically notifies the camera 104 on the network 103 of vehicle speed information.
The camera 104 sets a vehicle speed threshold value in advance. The threshold value on the high speed side is A, and the threshold value on the low speed side is B. Note that the threshold A and the threshold B are set so that no hunting phenomenon occurs in the control of the shutter speed of the camera 104 (for example, the difference between the threshold A and the threshold B is greater than or equal to a predetermined value).

FIG. 4 shows processing steps of the camera 104.
In step 401, the upper limit of the shutter speed is acquired from the console PC 110.
In step 411, vehicle speed information is received from the control unit 102.
In step 402, when the received speed information exceeds a predetermined threshold (hereinafter referred to as threshold A) (when the speed is increased), whether or not the shutter speed upper limit is set to be shortened again (hereinafter referred to as short setting). If the short setting is set (YES), the process proceeds to step 403. If the short setting is not set (NO), the process proceeds to step 405.

In Step 403, it is determined whether or not the received speed information is equal to or less than the threshold value B. If the speed information is equal to or greater than the threshold value B (NO), the process returns to Step 401, and if the speed information is equal to or less than the threshold value B ( If yes, go to Step 404.
In step 404, the upper limit of the shutter speed is changed to a long setting (for example, the exposure time is extended by 10%), and the process returns to step 401.

In step 405, it is determined whether or not the received speed information is greater than or equal to the threshold A. If the speed information is greater than or equal to the threshold A (YES), the process proceeds to step 406, and if the speed information is less than the threshold A ( If NO, the process returns to step 401.
In step 406, the upper limit of the shutter speed is changed to a short setting (for example, the exposure time is reduced by 10%), and the process returns to step 401.

Next, shutter speed control will be described with reference to FIG.
FIG. 5 is a diagram for explaining the shutter speed control of the camera.
As shown in FIG. 5, when the shutter speed reaches the upper limit, the detected light quantity decreases as the ambient illuminance becomes darker. If the detected light quantity is not sufficiently obtained by automatic shutter speed control and the image is dark, the image is brightened by AGC (Automatic Gain Control) control. When AGC control is used, noise tends to occur in the video. Therefore, it is better to use the shutter speed control as much as possible for the brightness control. For that purpose, it is desirable that the upper limit of the shutter speed is long. On the other hand, it is desirable that the upper limit of the shutter speed is short in order to reduce the afterimage when shooting a subject moving at high speed.

  In the setting of one embodiment of the present invention, noise is generated by shortening the upper limit of the shutter speed during high-speed driving where afterimage reduction is prioritized and increasing the upper limit of the shutter speed during low-speed driving or when the vehicle is at a low necessity for afterimage reduction. Can be reduced.

The threshold value in FIG. 4 is set based on the speed at which an afterimage is generated in the video. Strictly speaking, since an afterimage is generated in the video even when the shutter speed is shortened, the user arbitrarily sets a threshold based on whether the afterimage can be ignored when using the video.
In addition to the vehicle speed and shutter speed, the afterimage generation degree varies depending on the angle of view of the subject, the direction of camera installation relative to the vehicle traveling direction, and the like. Therefore, instead of using a fixed value as a device, the user can set an arbitrary value.

In addition, in the case of a camera using a lens having a zoom function, a change in the angle of view due to zoom may be included as a reference in addition to the vehicle speed as a reference for changing the upper limit of the shutter speed.
In FIG. 4, the threshold value is determined as one and the upper limit of the shutter speed is set to only the long setting and the short setting. However, the threshold value may be increased and the shutter speed may be changed more finely and stepwise. Alternatively, a method may be used in which the upper limit of the required shutter speed is calculated from the vehicle speed and the shutter speed is dynamically changed without using a threshold value.

Next, as a usage example of the speed information, a function for switching the camera output to be displayed according to the speed information will be described with reference to FIG.
FIG. 6 is a block diagram for explaining display switching of the monitoring apparatus according to the embodiment of the present invention.
When a plurality of cameras are installed in a vehicle depending on the installation location and purpose, the importance of these cameras varies depending on whether the camera is traveling or stopped.

FIG. 6 is an example when a plurality of cameras are installed in the vehicle 601.
The monitoring device of the vehicle 601 is installed for the purpose of photographing the rear of the last vehicle 601-2 and the camera 602 having a distribution function to the network 611 installed for the purpose of photographing the front of the leading vehicle 601-1. Receiving and decoding video data of a camera 603 having a distribution function to the network 612, a camera 604 having a distribution function to the network 612 for photographing the vicinity of the vehicle door 607, and the cameras 602, 603, and 604 It includes a WEB decoder 605 and a monitor 606 for displaying video data.

The WEB decoder 605 acquires vehicle speed information, and switches the display video of the monitor 606 according to the speed information.
Note that the network 611 and the network 612 may be one network or may be configured to connect a plurality of networks.

Next, an example of display on the monitor will be described with reference to FIG.
FIG. 7 is a view for explaining display switching of the monitor of the monitoring apparatus according to the embodiment of the present invention.
In FIG. 7, the monitor 606 displays the video output from the camera 602 in FIG. 6 on the video A, displays the video output from the camera 603 on the video B, and displays the video output from the camera 604 as the video C. indicate.

A display example 701 is an example of a monitor display during traveling. While the vehicle is traveling, the image A for photographing the front is displayed large, and the other images A, B, and C are displayed small. 702 display example 2 is an example of a monitor display during traveling backward, and video B is displayed in a large size, and another video B, video A, and video C are displayed in a small size. Display example 703 is an example of a monitor display while the vehicle is stopped. The video C is displayed in a large size, and the other video C, the video A, and the video B are displayed in a small size. Thus, by knowing the traveling speed information, it is possible to enlarge and display a useful video at each time point, and improve the added value of the video display.
Note that the position of the video to be displayed small may be arbitrary.

Next, an example of a monitor display changing method will be described with reference to FIG.
FIG. 8 is a flowchart for explaining the monitoring screen switching control according to the vehicle speed information of the monitoring apparatus according to the embodiment of the present invention.
FIG. 8 shows processing steps of the WEB decoder 605.
In step 801, vehicle speed information is acquired from the vehicle monitoring system or GPS of the vehicle 600 not shown.

In step 802, it is determined whether or not the vehicle speed is equal to or lower than a predetermined value (for example, 5 km / h). If the vehicle speed is equal to or lower than the predetermined value (YES), the process proceeds to step 803. Advances to step 806.
In step 803, it is determined that the vehicle is stopped, and the process proceeds to step 804.
In step 804, it is determined whether or not the display on the monitor 606 is a traveling state monitoring screen. If the traveling state monitoring screen is displayed (YES), the process proceeds to step 805. If the stopped state monitoring screen (NO), the step is performed. Returning to the processing of 801.
In step 805, the display on the monitor 606 is changed to a stop state monitoring screen shown in 703 display example 3 in FIG.

In step 806, it is determined that the vehicle is traveling, and the process proceeds to step 807.
In step 807, it is determined whether or not the display of the monitor 606 is a stop state monitoring screen. If the stop state monitoring screen (YES), the process proceeds to step 808. If the stop state monitoring screen (NO), step 807 is performed. Returning to the processing of 801.
In step 808, the display on the monitor 606 is changed to a traveling state monitoring screen as shown in 701 display example 1.

In addition, since it is desirable that the predetermined value of the vehicle speed is arbitrarily switched by an administrator of the vehicle monitoring system, the setting can be changed.
Further, the speed information received by the camera may be added to the video data, and the WEB decoder 605 may acquire the speed information from the video information received from the camera.
The video information is information including video data and speed information.

Next, an example of searching for a video recording apparatus will be described with reference to FIG.
FIG. 9 is a flowchart for explaining a procedure for detecting video data from position information of the monitoring apparatus according to the embodiment of the present invention.
FIG. 9 shows processing steps of the video recording apparatus 109.

In step 901, the GPS information of the place where the video is to be searched is received and the search is started.
In step 902, position information is acquired from the recorded video information, and the process proceeds to step 903.
In step 903, it is determined whether or not they match with the GPS information designated as the search target. If the position information matches (YES), the process proceeds to step 904, and if the position information does not match (NO). Advances to step 905.
In step 904, the video information is additionally stored in the search result table, and the process proceeds to step 905.

In step 905, it is determined whether or not the search for all video information has been completed. If completed (YES), the process proceeds to step 906. If not completed (NO), the process proceeds to step 907. .
In step 906, the search result table is displayed on the monitor 107, and the process ends.
In step 907, the next video information is searched, and the process returns to step 902.

Next, details of the processing in step 903 in FIG. 9 will be described with reference to FIG.
FIG. 10 is a flowchart for explaining an example of a method for determining whether or not the GPS information of the monitoring apparatus according to an embodiment of the present invention and the position information in the video information match.

FIG. 10 shows processing steps of the video recording device 109.
In step 1001, the square of the distance from the position to be searched to the position indicated by the position information in the video information (the position at the time when the video was shot) is set as the evaluation value I, and I is expressed by (Expression 1). calculate.
I = (cos θ) ² × (Δφ) ² + (Δθ) ² ... (Formula 1)
Here, θ is the latitude of the designated GPS information, θ is the longitude of the designated GPS information, Δθ is the latitude difference from the position information in the video information, and Δφ is the longitude difference from the position information in the video information.

In step 1002, it is determined whether or not the evaluation value I is smaller than the determination threshold L. If the evaluation value I is smaller than the determination threshold L (YES), the process proceeds to step 1003, and the evaluation value I is determined. If it is equal to or greater than the threshold L (NO), the process proceeds to step 1004.
In step 1003, it is determined that the position information matches, and the process ends.
In step 1004, it is determined that the position information is different, and the process ends.

  Note that factors that determine the threshold value L include vehicle operation speed, recording frame rate, GPS position resolution, and the like. Since these values vary depending on the operating environment, the system administrator can change them to arbitrary values.

  Further, as a distance search method, there is a binary search by cutting a section. The first GPS information and the last GPS information in the search section are compared, and when the designated GPS information is included in the range, the position information corresponding to the center of the section is compared with the designated GPS information. If the designated GPS information is between the GPS information at the beginning of the search section and the GPS information at the center of the section, this time, comparison is made with the GPS information at the beginning of the search section and the center of the search section. By repeating this, the number of searches is reduced and the corresponding video data of the designated GPS information is narrowed down. This binary search method may be used as a position search method.

Furthermore, a GUI (Graphical User Interface) may be used when specifying GPS information with the console PC 110 of FIG. For example, a method may be used in which a map of a section in which the vehicle moves is displayed, a position is designated using a pointing device, and video search is performed using GPS information of the position. Further, other information may be used in combination during the search. As an example, the range of video data to be searched is narrowed down by using time information, operation section information, or the like.
Although the method using GPS information has been described above as a method for acquiring vehicle position information, a method for specifying a position using a travel distance may be used. In a railway vehicle running on a track, the vehicle position can be uniquely determined by obtaining the travel distance from the reference point. By using this method, the position variable is determined by a single variable, so that the position search can be simplified and the amount of calculation can be reduced. Also, position information can be acquired even in a tunnel where GPS cannot be used. Further, by correcting the travel distance at a fixed point on the route, it is also possible to reduce an error between the actual travel distance and the calculated position. In some cases, both a method of using GPS information and a method of calculating a position from a travel distance may be used in combination.

  According to the above-described embodiment, in the monitoring device including the camera and the recording device mounted on the vehicle, the exposure time of the camera can be controlled according to the moving speed of the vehicle. The recording device can store the video data of the camera and the vehicle position information in association with each other. Furthermore, the video data stored in the recording device can be searched based on the vehicle position information.

  Although the present invention has been described in detail above, it is needless to say that the present invention is not limited to the monitoring device described here, and can be widely applied to other monitoring devices.

  This application claims the benefit of priority based on Japanese Patent Application No. 2013-251210 filed on Dec. 4, 2013, the entire disclosure of which is incorporated herein by reference.

  The present invention relates to a monitoring apparatus, and is suitable, for example, for a monitoring apparatus in which a camera is installed in a vehicle that moves at high speed.

  101: Vehicle, 102: Control unit, 104, 105: Camera, 103: Network, 106: WEB decoder, 107: Monitor, 108: Position information detection device, 109: Video recording device, 110: Console PC, 601: Vehicle 601-1: Lead vehicle, 601-2: Last vehicle, 602, 603, 604: Camera, 605: WEB decoder, 606: Monitor, 607 to 610: Door, 611, 612: Network.

Claims (3)

Vehicle speed detection for detecting vehicle speed based on position information detected by image pickup means installed in a vehicle, exposure control means for controlling exposure time of the image pickup means, vehicle position detection means, and vehicle position detection means With means,
The monitoring apparatus according to claim 1, wherein the exposure control means controls an exposure time of the imaging means according to the vehicle speed detected by the vehicle speed detection means. Vehicles based on a plurality of image pickup means installed in the vehicle, display means, display control means for controlling signals displayed on the display means, vehicle position detection means, and position information detected by the vehicle position detection means Vehicle speed detecting means for detecting the speed,
The monitoring apparatus, wherein the display control means controls selection of an imaging means output to be displayed or a combination of a plurality of imaging means outputs according to the vehicle speed detected by the vehicle speed detection means. An image pickup means installed in the vehicle, a vehicle position detection means, a recording means, and a search means for searching the storage means of the storage means,
The imaging means associates the video data imaged by the imaging means with the position information detected by the vehicle position detection means and outputs it as video information,
The recording means records the video information;
The monitoring device, wherein the search means searches the video data stored in the storage means based on the position information.