JP2004171419A - Traffic flow measurement processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a traffic flow measurement processor capable of rapidly obtaining an image by each imaging means within a necessary range by selectively loading an image frame constituting the image from each imaging means. <P>SOLUTION: This processor is provided with a plurality of imaging means consisting of fixed cameras 10 for outputting taken images as image frames at a prescribed frame number per second, respectively, and a switching means consisting of an image switching part 12 for selectively loading the image frame related to each image taken by a plurality of imaging means consisting of the fixed cameras 10. This processor is further provided with an image processing means consisting of an image processing part 13 for performing the image processing of the image frame selectively loaded by the switching means consisting of the image switching part 12. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a traffic flow measurement processing device, and more particularly to a traffic flow measurement process for switching and processing a plurality of ITV camera images, measuring traffic conditions in a specific section by comparing traveling vehicle images, and efficiently storing and transmitting the images. It concerns the device.
[0002]
[Prior art]
[0003]
In a conventional traffic flow measurement processing device, images from a plurality of ITV cameras are input while switching images from an image switch to a controller, and the presence or absence of a vehicle in the images of each ITV camera is determined by image processing (for example, Patent Document 1).
According to this conventional technique, when the result of the determination indicates that a vehicle is present or the vehicle is likely to be slow or stopped, a video switching stop instruction is given to the video switcher to fix the current ITV camera video. The image processing is continued, and the low speed / stop event of the vehicle is detected.
[0004]
[Patent Document 1]
JP-A-11-288495 [0005]
[Problems to be solved by the invention]
Since the conventional traffic flow measurement processing device is configured as described above, when processing is performed by fixing an image to a certain camera, image processing of a monitoring section of another camera cannot be performed. There is a problem that even when an event occurs, it cannot be detected.
[0006]
The present invention has been made in order to solve the problems in the above processing device, and selectively captures image frames constituting a video from each imaging unit so that the video by each imaging unit can be obtained within a necessary range. It is an object of the present invention to provide a traffic flow measurement processing device that can be quickly obtained.
[0007]
[Means for Solving the Problems]
In the traffic flow measurement processing device according to the present invention, the traffic flow measurement processing device further includes a switching unit that selectively captures an image frame of a video captured by a plurality of imaging units that output captured images as image frames at a predetermined number of frames per second, An image processing means for performing image processing on the image frame selectively captured by the switching means is provided.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG.
First Embodiment A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing an overall configuration according to the first embodiment. FIG. 2 is a block diagram showing a functional configuration according to the first embodiment.
[0009]
In FIG. 1, a plurality of ITV cameras 10 for monitoring the inside of the tunnel 1 are provided in the tunnel 1 to be monitored.
The ITV camera 10 is connected to the control device CA, and images from the ITV camera 10 are taken in and distributed by the control device CA.
The control center CC receives the image of the ITV camera 10 from the control device CA and displays it on the monitor MN.
The image of the ITV camera 10 is distributed to the traffic flow measurement processing device main body 11 from the control device CA.
[0010]
In FIG. 2, an image from a monitoring ITV camera 10 is input to a traffic flow measurement processing device main body 11 via input means 11a.
The traffic flow measurement processing device main body 11 includes a plurality of terminals for inputting the video signal of the connected ITV camera 10, and a video switching unit 12 and a video switching unit that generate a digitized image while switching the input video signal at high speed. An image processing unit 13 is provided for receiving the digitized image from 12 and processing it.
The monitoring ITV camera 10 outputs captured images as image frames at a predetermined number of frames per second, such as 30 frames / second.
[0011]
The image processing unit 13 detects, for example, an event that hinders traffic such as a low-speed vehicle existing on a road in a section of about 100 m in an image of the ITV camera 11.
On the other hand, a low-speed vehicle traveling at, for example, 40 km / h moves about 10 m per second. For example, if two images can be acquired per second, 20 images are acquired to travel in a section of 100 m of the low-speed vehicle. This is sufficient for detecting and determining low-speed vehicles.
[0012]
On the other hand, the video signal includes 30 images per second. That is, it is composed of image frames having the number of frames per second of 30 frames / second.
Therefore, for example, the images of five ITV cameras 10 are switched every 1/10 second by the image switching unit 12, and when images are input one by one every 1/10 second, each image is converted into two images every second. It can be passed to the processing unit 13.
High-speed video switching by the video switching unit 12 can be realized by using, for example, an analog / digital conversion LSI having a plurality of inputs.
[0013]
As described above, according to this embodiment, by processing images of a plurality of ITV cameras with one traffic flow measurement processing device, the number of traffic flow measurement processing devices can be reduced, and cost can be reduced. Since there is no non-monitoring time, events can be detected without omission.
[0014]
According to the first embodiment of the present invention, a plurality of image pickup means including an ITV fixed camera 10 for outputting a captured image as image frames at a predetermined frame rate per second, and a plurality of image pickup means including the ITV fixed camera 10 And a switching unit including a video switching unit 12 for selectively capturing an image frame of a video captured by the image processing unit, and performing image processing on the image frame selectively captured by the switching unit including the video switching unit 12. Since the image processing means including the processing unit 13 is provided, by selectively capturing image frames constituting the image from each imaging means, it is possible to quickly obtain the image by each imaging means within a necessary range. A measurement processing device can be provided.
[0015]
Embodiment 2 FIG.
Embodiment 2 of the present invention will be described with reference to FIG. FIG. 3 is a block diagram showing a functional configuration according to the first embodiment.
In the second embodiment, the configuration other than the specific configuration described here has the same configuration contents as the configuration in the first embodiment described above, and has the same operation. In the drawings, the same reference numerals indicate the same or corresponding parts.
[0016]
In FIG. 3, a digital compression conversion unit 14 for converting images from a plurality of ITV cameras 10 into digital compressed images such as MPEG or motion JPEG is provided. A compressed video decompression unit 15 for decompressing the compressed digitally compressed image is provided.
The data exchange between the digital compression conversion unit 14 and the compressed video decompression unit 15 may be performed using a network such as a LAN (Local_Area_Network), and the digital compressed image signal from the digital compression conversion unit 14 is used for traffic flow measurement. The data is input to the compressed video decompression unit 15 via an input unit 11a of the processing apparatus main body 11 which is a network such as a LAN.
[0017]
According to this method, it is not necessary to provide a plurality of video input terminals for the traffic flow measurement processing device. For example, if there is one LAN terminal having a communication speed of 100 Mbps, an MPEG video of 6 Mbps can be converted into data of five video data ( 30 Mbps), and the traffic flow measurement processing device can be downsized.
[0018]
According to the second embodiment of the present invention, in the configuration of the first embodiment, the output from the imaging unit including the plurality of ITV cameras 10 includes the switching unit including the video switching unit 12 and the image processing unit 13. An input unit 11a for inputting digital image data to the traffic flow measurement processing device main body 11 including an image processing unit is provided, and the input unit 11a is configured by a network. By selectively capturing, it is possible to provide a traffic flow measurement processing device that can quickly obtain an image from each imaging unit within a necessary range and can simplify the image input configuration.
[0019]
Embodiment 3 FIG.
Embodiment 3 of the present invention will be described with reference to FIG. FIG. 4 is a block diagram showing a functional configuration according to the third embodiment.
In the third embodiment, components other than the specific configuration described here have the same configuration contents as those in the first and second embodiments described above, and have the same functions. It is. In the drawings, the same reference numerals indicate the same or corresponding parts.
[0020]
In FIG. 4, a compression setting information storage unit 16 for setting a video compression method for the digital compression conversion unit 14 is provided. A compressed video simple decompression unit 17 for easily decompressing an image is provided.
[0021]
As a moving image compression method, there is a method such as MPEG which performs compression using difference information between video frames.
Even in such a method, compression is performed within one frame to provide a frame that does not include difference information between frames. For example, in MPEG, it is called an I frame.
If the compression setting information stored in the compression setting information storage unit 16 is set in advance to have an I frame at a cycle required by the image processing unit 13, the compressed video simple decompression unit 17 decompresses only this I frame. What is necessary is just to skip the frame using the difference information between frames.
[0022]
According to this method, the processing load can be suppressed by simply expanding the compressed video, and the traffic flow measurement processing device can be downsized.
[0023]
According to the third embodiment of the present invention, in the configuration in which the second embodiment is applied to the configuration of the first embodiment, video compressed data in which image frames that are not subjected to inter-frame compression are arranged at predetermined video capturing periods. Input means 11a for taking in as a video input, and a compressed video simple decompression unit 17 for cutting out only the image frames not subjected to inter-frame compression from the video data taken in as video input by the input means 11a and performing image processing. Since the compressed video simple decompression means is provided, by selectively capturing the image frames constituting the video from each imaging means, the video by each imaging means can be quickly obtained within a necessary range, and the compressed video It is possible to provide a traffic flow measurement processing device that can easily perform expansion and suppress processing load.
[0024]
Embodiment 4 FIG.
Embodiment 4 of the present invention will be described with reference to FIGS. FIG. 5 is a block diagram showing a functional configuration according to the fourth embodiment. FIG. 6 is an explanatory diagram illustrating the measurement principle of the travel time measurement unit according to the fourth embodiment.
In the fourth embodiment, the configuration other than the specific configuration described here has the same configuration content as the configuration in the first to third embodiments described above and has the same operation. It is. In the drawings, the same reference numerals indicate the same or corresponding parts.
[0025]
In FIG. 5, a vehicle image storage unit 18 that stores a partial image of a passing vehicle cut out by the image processing unit 13 for each input image is provided, and a vehicle image in the vehicle image storage unit 18 is used to store information between two ITV camera positions. Is provided with a travel time measuring unit 19 for measuring the travel time.
[0026]
Next, the travel time measuring unit 19 will be described with reference to FIG.
In FIG. 6, an ITV camera 31 is installed on the upstream side of the road 30 to be observed, and an ITV camera 32 is installed on the downstream side of the ITV camera 31. The vehicle 33 travels on the road 30, an image 34 of the vehicle 33 is acquired by the ITV camera 31, and an image 35 of the vehicle 33 is acquired by the ITV camera 32.
[0027]
The travel time measuring unit 19 compares the vehicle image 34 and the vehicle image 35 to determine whether the vehicle is the same vehicle.
This determination may be made using, for example, the shape and color of the vehicle, the number of the license plate, and the like.
If it is determined that the vehicle is the same, the travel time of the section D is measured from the acquisition times Ta and Tb of each vehicle image.
The travel time may be measured using a single vehicle as described above, or may be measured using a plurality of vehicles.
[0028]
As described above, in the fourth embodiment, images acquired by a single image processing unit can be directly compared, and travel time can be accurately measured.
[0029]
According to the fourth embodiment of the present invention, in the configuration of the first to third embodiments, a vehicle image detected from an image observing an upstream portion of a road is stored for an image observing a predetermined point on a road. A travel time measuring unit 19 for determining whether or not the vehicle is the same vehicle by comparing the detected vehicle image with a vehicle image detected from an image observing a downstream portion of the road, and measuring a travel time between points of the same vehicle; By selectively capturing the image frames that compose the video from each imaging means, the video from each imaging means can be obtained quickly within the required range, and the traveling time of the vehicle can be accurately and appropriately adjusted. It is possible to provide a traffic flow measurement processing device that can perform measurement in a short time.
[0030]
Embodiment 5 FIG.
Embodiment 5 of the present invention will be described with reference to FIG. FIG. 7 is a block diagram showing a functional configuration according to the fifth embodiment.
In the fifth embodiment, components other than the specific configuration described here have the same configuration contents as those in the first to fourth embodiments described above, and have the same functions. It is. In the drawings, the same reference numerals indicate the same or corresponding parts.
[0031]
In FIG. 7, a passing vehicle checking unit 20 that checks a vehicle traveling in a section between cameras using a vehicle image 18 is provided.
[0032]
The passing vehicle checking unit 20 checks the image of the passing vehicle and the number information on the section between the two ITV cameras 10 installed upstream and downstream of the road where there is no merging, and outputs the passing vehicle information. provide.
The on-vehicle information is the same as that obtained by temporarily accumulating the vehicle images of each passing vehicle obtained from the ITV camera installed upstream and comparing the vehicle images of each passing vehicle obtained from the ITV camera installed downstream. By discarding the determined vehicle image, it is possible to obtain the image of the vehicle currently passing and the information on the number of vehicles.
[0033]
As described above, in the fifth embodiment, it is possible to obtain the on-vehicle vehicle information in the section between the cameras.
If this function is applied to, for example, a section between cameras installed at the entrance of a tunnel, information on vehicles left in the tunnel at the time of a tunnel disaster can be obtained, which can be used for rescue activities and the like.
[0034]
According to the fifth embodiment of the present invention, in the configuration according to the first to fourth embodiments, an image of observing a point at an upstream portion and a downstream portion of a specific section of a road without a branch is used to observe the upstream portion of the road. The vehicle image detected from the moving image is stored, and it is determined whether the vehicle is the same vehicle by comparing the detected vehicle image with the vehicle image detected from the image observing the downstream portion of the road. Since the vehicle is provided with a passing vehicle confirmation unit including a passing vehicle confirmation unit 20 capable of confirming the number, the image frames constituting the image from each imaging unit can be selectively taken in, so that the image by each imaging unit can be obtained within a necessary range. It is possible to provide a traffic flow measurement processing device that can be quickly obtained and that can appropriately confirm the image of the vehicle being passed and the number of vehicles.
[0035]
Embodiment 6 FIG.
Embodiment 6 of the present invention will be described with reference to FIG. FIG. 8 is a block diagram showing a functional configuration according to the sixth embodiment.
In the sixth embodiment, components other than the specific configuration described here have the same configuration contents as those in the first to fifth embodiments described above, and have the same functions. It is. In the drawings, the same reference numerals indicate the same or corresponding parts.
[0036]
In FIG. 8, a moving image compression / synthesis unit 21 obtains images from a plurality of ITV cameras 10 while switching them from a video switching unit 12, synthesizes the obtained images singly or into two or four screens, Compress using the moving image compression method.
[0037]
In this embodiment, an image used for image processing can be confirmed, a moving image can be efficiently transmitted by performing synthesis and compression, and an image input can be processed by acquiring an image from the image switching unit 12. The traffic flow measurement processing device can be miniaturized by sharing with the unit 13.
[0038]
According to the sixth embodiment of the present invention, in the configuration of the first to fifth embodiments, a moving image compression unit including a moving image compression / synthesis unit 21 for compressing a captured image into a moving image is provided. By selectively capturing the image frames that compose the video from each imaging means, it is possible to quickly obtain the video from each imaging means within a required range and to efficiently transmit and process moving images. A processing device can be provided.
[0039]
Embodiment 7 FIG.
Embodiment 7 of the present invention will be described with reference to FIG. FIG. 9 is a block diagram showing a functional configuration according to the seventh embodiment.
In the seventh embodiment, the configuration other than the specific configuration described here has the same configuration as the configuration in the first to sixth embodiments described above, and has the same operation. It is. In the drawings, the same reference numerals indicate the same or corresponding parts.
[0040]
In FIG. 9, a compression ratio control unit 22 receives traffic flow information from the image processing unit 13 and changes the compression ratio of a moving image in the moving image compression / synthesis unit 21 based on the traffic flow information.
[0041]
The compression ratio control unit 22 normally sets the compression ratio of the moving image to be high in the moving image compression / synthesis unit 21, suppresses the data amount of the compressed moving image, and allows the compressed moving image to be transmitted efficiently. In addition, when, for example, detection information of a stopped vehicle is received from the image processing unit 13, the compression ratio of the moving image is reduced by the moving image compression / synthesis unit 21 so that a high-definition moving image is generated. Facilitate understanding of the situation when checking the image.
[0042]
As described above, in the seventh embodiment, the data amount of the compressed moving image is suppressed in the normal state, the transmission of the compressed moving image is made more efficient, and the moving image is made higher definition when an event occurs to facilitate the situation grasp. Can be.
[0043]
According to the seventh embodiment of the present invention, a video compression unit including a moving image compression / synthesis unit 21 for compressing a captured video, and a compression ratio control unit 22 for dynamically changing a video compression ratio by the video compression unit. Compression rate control means comprising: a compression rate control means comprising the compression rate control section 22 in response to occurrence of a predetermined event such as a traffic jam or a stopped vehicle. By changing the compression ratio so that it is lower than the non-occurrence state of the predetermined event, when a predetermined event such as traffic congestion or a stopped vehicle is detected, the video compression ratio is normally increased to reduce the communication volume. When an event occurs, the image quality is enhanced by enhancing the image quality and the function of making it easy to visually recognize the event occurrence. By selectively capturing the video, it is possible to quickly obtain the video from each imaging means within the required range, streamline the transmission of the compressed video, and make it easier to grasp the situation by increasing the resolution of the video when an event occurs It is possible to provide a traffic flow measurement processing device that can perform the following.
[0044]
Embodiment 8 FIG.
An eighth embodiment according to the present invention will be described with reference to FIG. FIG. 10 is a block diagram showing a functional configuration according to the eighth embodiment.
In the eighth embodiment, the configuration other than the specific configuration described here has the same configuration content as the configuration in the first embodiment described above, and has the same operation. In the drawings, the same reference numerals indicate the same or corresponding parts.
[0045]
In FIG. 10, the event video storage unit 23 captures the traffic flow information from the image processing unit 13 and the compressed moving image generated by the moving image compression / synthesis unit 21, and the image processing unit 13 detects an event such as a stopped vehicle. The compressed video at that time is stored as the event video 24.
[0046]
When the event video storage unit receives, for example, information on detection of a stopped vehicle from the image processing unit 13, the event video storage unit captures the corresponding compressed moving image of the ITV camera 10 and stores it as a video including an event occurrence state of, for example, about 30 seconds.
At this time, video of about 15 seconds may be sequentially stored in advance using a ring buffer or the like, and when an event occurs, the video before and after the event may be stored together with the video in the ring buffer.
Further, information such as an occurrence event and an occurrence date and time may be added to the video image so that the search can be easily performed.
[0047]
As described above, in the eighth embodiment, the video at the time of occurrence of an event can be later searched and confirmed, and the situation at the time of occurrence of the event can be confirmed.
[0048]
According to the eighth embodiment of the present invention, when an event of a traffic jam or a stopped vehicle is detected, a moving image compressed image before and after the occurrence of the event is cut out from the captured image to search for an event name, an occurrence date and time, and the like. Since an event video storage unit including an event video storage unit 23 for adding and storing information is provided, an image frame constituting a video from each imaging unit is selectively taken in, so that the video by each imaging unit is required. It is possible to provide a traffic flow measurement processing device which can be quickly obtained in a range and can easily confirm the situation at the time of occurrence of an event.
[0049]
【The invention's effect】
According to the present invention, it is possible to provide a traffic flow measurement processing device capable of quickly obtaining an image from each imaging unit within a necessary range by selectively taking in an image frame constituting an image from each imaging unit.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an overall configuration according to a first embodiment of the present invention.
FIG. 2 is a block diagram showing a functional configuration according to the first embodiment of the present invention.
FIG. 3 is a block diagram showing a functional configuration according to a second embodiment of the present invention.
FIG. 4 is a block diagram showing a functional configuration according to a third embodiment of the present invention.
FIG. 5 is a block diagram showing a functional configuration according to a fourth embodiment of the present invention.
FIG. 6 is an explanatory diagram illustrating a measurement principle of a travel time measurement unit according to a fourth embodiment of the present invention.
FIG. 7 is a block diagram showing a functional configuration according to a fifth embodiment of the present invention.
FIG. 8 is a block diagram showing a functional configuration according to a sixth embodiment of the present invention.
FIG. 9 is a block diagram showing a functional configuration according to a seventh embodiment of the present invention.
FIG. 10 is a block diagram showing a functional configuration according to an eighth embodiment of the present invention.
[Explanation of symbols]
10 ITV camera, 11 traffic flow measurement processing device main body, 11a input means, 12 video switching unit, 13 image processing unit, 14 digital compression conversion unit, 15 compressed video expansion unit, 16 compression setting information, 17 compressed video simple expansion unit, 18 vehicle image, 19 travel time measurement unit, 20 passing vehicle confirmation unit, 21 moving image compression / synthesis unit, 22 compression ratio control unit, 23 event video storage unit, 24 event video, 30 road, 31 upstream ITV camera, 32 Downstream ITV camera, 33 vehicle, 34 vehicle image, 35 vehicle image.

Claims (8)

A plurality of image capturing means for outputting captured images as image frames at a predetermined number of frames per second, and switching means for selectively capturing image frames related to images captured by the plurality of image capturing means; A traffic flow measurement processing device provided with image processing means for performing image processing on an image frame selectively captured by the method. Input means for inputting outputs from the plurality of imaging means to the traffic flow measurement processing device main body including the switching means and the image processing means as digital video data, wherein the input means is constituted by a network. The traffic flow measurement processing device according to claim 1. Input means for inputting, as a video input, video compressed data in which image frames that are not subjected to inter-frame compression are arranged at predetermined video input periods, and perform inter-frame compression from video data input as video input by the input means. 3. The traffic flow measurement processing device according to claim 2, further comprising a compressed video simple decompression unit that cuts out only the non-existing image frames and performs image processing. For a video observing a predetermined point on the road, save the vehicle image detected from the image observing the upstream section of the road, and compare it with the vehicle image detected from the image observing the downstream section to determine whether the vehicle is the same vehicle. The traffic flow measurement processing device according to any one of claims 1 to 3, further comprising travel time measurement means for determining a travel time between points with respect to the same vehicle. For images of observing points at the upstream and downstream of a specific section of a road without branches, save vehicle images detected from images observing the road upstream, and vehicles detected from images observing downstream of the road. The vehicle according to any one of claims 1 to 4, further comprising a vehicle-to-vehicle confirming means for determining whether or not the vehicle is the same by comparing the image with the image and confirming a vehicle image and the number of vehicles traveling in a specific section. The traffic flow measurement processing device according to any one of the above. The traffic flow measurement processing device according to any one of claims 1 to 5, further comprising a moving image compression unit that compresses the captured image into a moving image. Video compression means for compressing the captured video, and compression rate control means for changing the video compression rate of the video compression means, wherein the video data is compressed by the video compression means by the compression rate control means in response to occurrence of a predetermined event. The traffic flow measurement processing device according to claim 6, wherein the compression ratio is changed so as to be lower than a state in which the predetermined event does not occur. The traffic according to claim 6 or 7, further comprising an event video storage unit that cuts out the compressed video before and after the occurrence of the event from the captured video and adds and stores search information. Flow measurement processing device.

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