JP3542237B2 - Moving object recognition method and apparatus - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image recognition system, and more particularly to a suitable recognition method and apparatus for obtaining an image at an optimal timing in recognizing a high-speed moving object.
[0002]
[Prior art]
When recognizing a high-speed moving object, it is essential to obtain an image suitable for recognizing a target moving object. For that purpose, it is necessary to detect that the moving object has reached a position suitable for recognition. Conventionally, this detection method includes a method of detecting an intrusion of a moving object by a sensor as described in Japanese Patent Publication No. 62-7588, and then taking an image, and a method of detecting whether a target moving object has come by an image processing device. However, here, a description will be given of an image processing apparatus that monitors whether a target moving object has arrived. In the conventional method, the timing for monitoring whether or not a target moving object has arrived has been defined by the specifications of the video signal of the camera to be used. For example, if a non-interlaced NTSC camera is used, images are taken at a minimum of about 16.7 ms from the specification of 60 screens per minute, and the video is image-processed. It is possible to monitor whether or not. However, if image processing is to be performed on the entire area that can be imaged by the camera, it takes 16.7 ms by itself, and the time for performing the image processing is lost. Therefore, only the first part of the area that can be imaged by the camera is used. Captured image processing was performed.
[0003]
[Problems to be solved by the invention]
In the prior art, for example, when a camera of the NTSC specification is used in a non-interlace mode, images can be taken only at a minimum interval of about 16.7 ms. There is a problem in that even if the entire area where the camera can image is taken, if the target moving object is at a high speed, the moving object passes through a recognizable area within 16.7 ms.
[0004]
Also, in this case, even if an attempt is made to use the video used for detection for recognition, since the video for detection is part of the area that can be captured by the camera, the recognition target portion may be partially captured, There was a problem that it could not be recognized.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to provide an efficient recognition method and apparatus that can follow a moving object that moves at a high speed that cannot be recognized by a conventional method and that is efficient.
[0006]
[Means for Solving the Problems]
An object of the present invention is to output a vertical synchronization interval of a camera at an interval shorter than the video specification of a camera to a camera that allows external synchronization input, and to make a minimum interval of imaging shorter than the video specification of the camera. Increases the number of monitoring times per unit time, shortens the interval from the detection of the target moving object to the image of the recognition image, and enables recognition at the vertical synchronization interval for imaging the entire imageable area of the camera This is achieved by making it possible to capture an image of a high-speed moving object that passes through a specific area in a recognizable area. Note that when capturing the recognition video, the synchronous output to the camera is output in accordance with the camera's original video specifications in order to capture the entire area that can be captured by the camera.
[0007]
An object of the present invention is to convert a video signal from a camera from analog data to digital data, convert the analog-to-digital information into a recognition area in a video memory, and detect an information in an image memory. The part of the area is saved, the target moving object is detected in the image memory, and when the target moving object is detected, the information of the recognition area stored in the video memory is stored in the image memory. It is also achieved by transferring and performing recognition processing.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
According to the present invention, it is possible to output at an arbitrary interval the vertical synchronization interval of a synchronization signal to be output to a camera capable of externally inputting vertical synchronization defining the starting point of scanning of a field, so that the entire area that can be imaged by the camera When only the first part of the image is captured, more images can be captured per unit time than when the camera is used at the vertical synchronization interval for capturing the entire imageable area of the camera.
[0009]
According to this, for example, in the case where the detection area is about 1/3 of the entire area that can be imaged by the camera, and the vertical synchronization interval of the synchronization signal output to the camera is set to １ ／ of the area for imaging the entire imageable area of the camera. The detection processing can be performed twice per unit time than when the camera is used at the vertical synchronization interval for imaging the entire imageable area of the camera, and the movement between the imaging of the moving object in the imaging area and the next imaging can be performed. The distance is also halved, making it possible to cope with a high-speed moving body twice as fast as the conventional method.
[0010]
Further, according to the present invention, a video signal from a camera is converted from analog data to digital data, and the information converted from analog to digital can be simultaneously stored in a video memory and an image memory, and the image memory is in the process of storing. The video signal from the camera can be continuously converted from analog data to digital data while the censored image processing is being performed, and the information converted from analog to digital can be stored in the video memory.
[0011]
According to this, while only the first part of the entire area that can be imaged by the camera for detecting a moving object is stored in the image memory, the entire area that can be imaged by the camera for recognizing the moving object at the same time is stored in a video. When a moving object is detected, the data of the entire image-capable area of the camera, which is stored in the video memory, can be transferred to the image memory, and the recognition process can be performed. It is possible to improve the ability to respond to a high-speed moving object.
[0012]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0013]
FIG. 1 is a schematic configuration diagram of the image processing apparatus of the present invention. The image processing apparatus 102 includes a control unit 103 including a CPU, a memory, an I / O interface, and the like, and an image processing unit 104. Note that a plurality of image processing units 104 may exist under one control unit 103. Next, the installation of the camera 108 will be described with reference to FIG. The camera 108 is installed such that the moving object 201 to be recognized passes through the center or almost the center of the imaging area 203 from above to below the imaging area 203. That is, for the moving object 201 to be recognized, the scanning start point 204 with respect to the imaging area of the camera starts in the direction in which the moving object comes, and the scanning end point 205 with respect to the imaging area of the camera is in the direction in which the moving object leaves. Install.
[0014]
Next, the variation of the synchronization interval will be described in detail with reference to FIGS. Here, as an example, a case where the vertical synchronization interval is set to の of the vertical synchronization interval for imaging the entire imageable area of the camera will be described. First, at step 401, the output timing controller sets the vertical synchronization interval to 垂直 of the vertical synchronization interval for imaging the entire imageable area of the camera. The setting is set in the output timing controller 106 through the signal line 105 by the control unit 103 in FIG. The output timing controller control unit 301 shown in FIG. 3 of the output timing controller 106 stores the number of horizontal scanning lines corresponding to the 1/2 setting value in the register 308. The calculation of the number of horizontal scanning lines may be performed by the control unit 103 of FIG. 1, by the control unit 301 of the output timing controller 106 of FIG. Or any of them. The counter 306 receives the synchronization signal from the synchronization generation circuit 303 through the signal line 304, counts the number of horizontal scanning lines from the start of the field, and transmits the count value to the control unit 309 through the signal line 305. The control unit 309 compares the counter value from the counter 306 with the value stored in the register 308. If the counter value from the counter 306 matches the value stored in the register 308, the control unit 309 sends the counter value to the synchronization generation circuit 303 through the control line 302. It notifies that the counter value from 306 coincides with the value of register 308. Upon receiving the notification from the output timing controller control unit 301, the synchronization generation circuit 303 immediately stops outputting the synchronization signal of the currently executing field and starts outputting the next field. The synchronization signal output to the camera 108 in this manner is different from the vertical synchronization interval 405 of the synchronization signal 403 of the camera in the entire imageable area as shown by 404 in 402 in FIG. The video signal from the camera 108 is as shown at 409 in 407.
[0015]
Next, writing to the memory will be described in detail with reference to FIG. A video signal from the camera 108 is input to an input timing controller 114 and an analog / digital converter (hereinafter, referred to as A / D) 110 through a signal line 109. The input timing controller 114 separates the synchronizing signal from the video signal, generates a timing signal for converting the video signal from the camera 108 into a pixel, and transmits the timing signal to the A / D 110, video memory, and data controller via the signal line 112. The A / D 110 converts the video signal from the camera 108 from analog data to digital data in accordance with the timing signal from the input timing controller 114, and transmits it to the video memory 113 and the data controller 116 via the signal line 111. The video memory 113 stores the digital signal from the A / D 110. Further, the data controller 116 follows a setting transmitted from the control unit 103 through the signal line 105,
(1) The digital signal from the A / D 110 is stored in the image memory 120 through the signal line 119.
[0016]
(2) The digital signal from the A / D 110 is partially stored in the image memory 120 through the signal line 119.
[0017]
(3) The contents of the video memory 113 are received through the signal line 115 and stored in the image memory 120 through the signal line 119.
[0018]
(4) The contents of the video memory 113 are received through the signal line 115, the contents of the image memory 120 are received through the signal line 119, or the information from the image calculation unit 118 is received through the signal line 117, and the image output unit 122 is received through the signal line 121. Output.
[0019]
(5) The contents of the video memory 113 are received through the signal line 115 or the contents of the image memory 120 are received through the signal line 119 and output to the image operation unit 118 through the signal line 117.
[0020]
(6) The information from the image operation unit 118 is received through the signal line 117 and stored in the image memory 120 through the signal line 119.
[0021]
The above operations (1) to (6) are performed, and the functions of claim 2 are satisfied by the operations (1) and (2).
[0022]
Next, the embodiment will be described with reference to vehicle number recognition. 5 to 9 show examples applied to a vehicle number recognition system. FIG. 5 is a schematic configuration diagram of the vehicle number recognition system. The camera 108 is housed in a camera unit 506 and is connected to an image processing device 508 via a signal line in a support 507. The camera 108 is installed such that the recognition area 505 and the detection area 504 are as shown in FIG. 5 with respect to the moving direction 503 of the recognition target vehicle 501. The vehicle number recognition algorithm will be described with reference to FIG. When the algorithm START 601 is performed, a video capture 602 of the detection area 504 is performed, a vehicle detection process is performed on the captured image, and a vehicle detection determination 603 is performed. When the result of the vehicle detection determination 603 is not detected, a series of operations from the video capturing 602 is repeated. On the other hand, when the recognition target vehicle 501 is detected as a result of the vehicle detection determination 603, the video of the recognition area 505 is captured, and the vehicle number recognition process 604 is performed on the captured image. When the vehicle number recognition processing 604 is completed, the processing 605 of the system is performed based on the result, and then the processing stop determination 606 is performed. If the result of the stop determination 606 is a continuation, a series of operations from the video capturing 602 is repeated.
[0023]
Next, an operation using the algorithm of FIG. 6 will be described with reference to FIG. On the time axis 708, graduations are provided at every vertical synchronization interval 707 for imaging the entire imageable area of the camera. The time elapses in the direction of the arrow on the time axis 708. First, when the algorithm shown in FIG. 6 starts, the detection area 504 is fetched into the image memory 120 as shown in the image memory input image 709 at the time of the detection area imaging time 701. The detection processing is performed on the image memory input image 709 of the image memory 120 in the detection processing time 702. As a result, since the recognition target vehicle 501 has not been detected, the detection area 504 is fetched into the image memory 120 again as shown in the image memory input image 710 at the next imaging timing, that is, the detection area imaging time 703. The detection processing is performed on the image memory input image 710 of the image memory 120 in the detection processing time 704, and as a result, the recognition target vehicle 501 is detected and recognized in the recognition area imaging time 705 which is the next imaging timing. The area 505 is fetched into the image memory 120 as shown in the image memory input image 711, and the recognition processing is performed in the recognition processing time 706. At this time, if the recognition target vehicle 501 is a low / medium-speed vehicle, the progress as indicated by 712 is considered. At the first imaging timing 713 for the detection processing, the vehicle 501 is not detected because the recognition target vehicle 501 has not reached the detection area 504. At the next imaging timing 714 for detection processing, the vehicle is detected because the recognition target vehicle 501 has reached the detection area 504. At the next imaging timing 715 for recognition processing, since the license plate 502 of the recognition target vehicle 501 exists in the recognition area 505, the vehicle number can be recognized. However, when the recognition target vehicle 501 is a high-speed vehicle, as shown at 716, even if the vehicle detection can be performed, the movement amount of the recognition target vehicle 501 is large at the imaging timing 719 for the recognition processing, and the license plate 502 is moved. Since it does not completely fit within the recognition area 505, the vehicle number cannot be recognized.
[0024]
Next, the case where the technical concept of variable synchronization according to the present invention is applied will be described in detail with reference to FIG. It is assumed that the detection area 504 is 40% of the imageable area.
[0025]
The detection processing time is less than 10% of the vertical synchronization interval for imaging the entire imageable area of the camera.
[0026]
When imaging the detection area 504, the vertical synchronization interval is set to の of the vertical synchronization interval for imaging the entire imageable area of the camera.
[0027]
At the time of imaging of the recognition area 505, the vertical synchronization interval is set to the vertical synchronization interval for imaging the entire imageable area of the camera.
[0028]
Make an assumption. First, when the algorithm shown in FIG. 6 starts, the detection area 504 is fetched into the image memory at the time of the detection area imaging time 801 as shown in the image memory input image 807. The detection processing is performed on the image memory input image 807 of the image memory 120 in the detection processing time 802, and as a result, no vehicle is detected, so the detection area 504 is stored in the image memory 120 in the detection area imaging time 803. As shown in the image memory input image 808. A detection process is performed on the contents 810 of the image memory 120 in the detection processing time 804, and as a result, the vehicle is detected and the recognition area 505 is stored in the image memory 120 in the recognition area imaging time 805 which is the next imaging timing. Then, the image is input as shown in the image memory input image 809, and the recognition processing is performed in the recognition processing time 806. At this time, if the recognition target vehicle 501 is a low / medium-speed vehicle, the progress as indicated by 810 can be considered. At the first imaging timing 811 for the detection processing, the vehicle 501 is not detected because the recognition target vehicle 501 has not reached the detection area 504. At the next imaging timing 812 for detection processing, a vehicle is detected because the recognition target vehicle 501 has reached the detection area 504. At the next imaging timing 813 for recognition processing, since the license plate 502 of the recognition target vehicle 501 exists in the recognition area 505, the vehicle number can be recognized. Even when the recognition target vehicle 501 is a high-speed vehicle, as shown in 814, since the imaging interval is reduced to 、, the movement amount of the vehicle during that period is also reduced to 、, and the number of the recognition target vehicle 501 during the recognition processing is reduced. The plate 502 exists in the recognition area 505, and it becomes possible to recognize the vehicle number of a high-speed vehicle, which was impossible with the conventional method.
[0029]
Finally, the case where claims 2 and 3 of the present invention are applied will be described in detail with reference to FIG. As a premise,
When the detection area is imaged, the data is stored in both the video memory 113 and the image memory 120.
[0030]
-The data of the recognition area 505 is stored in the video memory 113.
[0031]
When the image of the data in the detection area 504 is captured, the storage of the captured data in the image memory 120 is stopped.
[0032]
At the time of the detection process, the detection is performed on an area in which an area of about 30 cm has been deleted by converting the first side of the detection area 504 (the side where the car enters) on the road surface where the car actually passes. This is to prevent a problem that the license plate 502 does not enter the recognition area 505 because the detection area 504 and the recognition area 505 are simultaneously imaged in the method of the present invention. Further, the deletion width varies depending on the system applied.
[0033]
Make an assumption. First, when the algorithm shown in FIG. 6 starts, the detection area 504 is captured in the image memory 120 as shown in the image memory 908 at the time of the imaging time 901, and the recognition area 505 is input to the video memory 113 in the video memory 113 at the same time. Captured as shown in image 906. Detection processing is performed on the image memory input image 908 of the image memory 120 in the detection processing time 902, and as a result, the recognition target vehicle 501 is not detected. The detection area 504 is fetched into the image memory 120 as shown in the image memory input image 909, and the recognition area 505 is fetched into the video memory 113 as shown in the video memory input image 907. The detection processing is performed on the image memory input image 909 of the image memory 120 for the detection processing time 904. As a result, when the recognition target vehicle 501 is detected, the video memory input image 907 of the video memory 113 is converted to the image memory 120. Is transferred as shown at 912, and recognition processing is performed in a time 905. At this time, if the recognition target vehicle 501 is a low- / medium-speed vehicle, the progress as indicated by 911 can be considered. At the first detection processing timing 912, the vehicle 501 is not detected because the recognition target vehicle 501 has not reached the area below the deletion line 915 of the detection area 504. At the next detection processing timing 913, the recognition target vehicle 501 is detected because the recognition target vehicle 501 has reached an area below the deletion line 915 of the detection area 504. At the next timing 914 for recognition processing, since the license plate 502 of the recognition target vehicle 501 exists in the recognition area 505, the vehicle number can be recognized. Even when the recognition target vehicle 501 is a high-speed vehicle, the license plate 502 of the recognition target vehicle 501 exists in the recognition area 505 as shown at 916. It becomes possible.
[0034]
【The invention's effect】
According to the present invention, the vertical synchronization of the synchronization signal of the camera can be set to an arbitrary interval. For example, if the period of the vertical synchronization is reduced to 以下 or less, the imaging interval for the detection processing of the moving object is also about one. / 2, and the moving distance of the moving body on the screen is also reduced to １ ／.
[0035]
Further, from the above-mentioned effect, there is an effect that it is possible to follow a moving object that moves at twice the speed of the conventional method.
[0036]
ADVANTAGE OF THE INVENTION According to this invention, in recognition of a moving body, it becomes possible to accumulate | store the image for a detection process in an image memory, and the video for a recognition process simultaneously to a video memory, and the image for a detection process and the image for a recognition process become possible. This has the effect of eliminating the time lag with the video.
[0037]
Further, from the effect that the time lag is eliminated, there is an effect that it is possible to follow a moving body that moves at a higher speed than the conventional method (about twice in the method of the present embodiment).
[Brief description of the drawings]
FIG. 1 is an example of a configuration diagram of an image recognition system of the present invention.
FIG. 2 shows an example of camera installation conditions of the image recognition system of the present invention.
FIG. 3 is an example of a configuration diagram of an output timing controller of the image processing apparatus of the present invention.
FIG. 4 is a flowchart illustrating an example of a schematic operation according to claim 1 of the present invention.
FIG. 5 is a configuration diagram of a vehicle number recognition system according to an embodiment of the present invention.
FIG. 6 is a flowchart illustrating a schematic operation of the vehicle number recognition system according to the embodiment;
FIG. 7 is an explanatory diagram illustrating a schematic operation when a conventional system is applied to the vehicle number recognition system of the embodiment.
FIG. 8 is an explanatory diagram illustrating a schematic operation in a case where claim 1 of the present invention is applied to the vehicle number recognition system of the embodiment.
FIG. 9 is an explanatory diagram illustrating a schematic operation when the claims 2 and 3 of the present invention are applied to the vehicle number recognition system of the embodiment.
[Explanation of symbols]
101: external equipment, 102, 508: image processing device, 103: control unit, 104: image processing unit, 105, 107, 109, 111, 112, 115, 117, 119, 121, 123, 302, 304, 305 ... Signal line, 106 output timing controller, 108 camera, 110 analog / digital converter, 113 video memory, 114 input timing controller, 116 data controller, 118 image operation unit, 120 image memory, 122 Video output unit, 200: recognition target moving body, 202: recognition target moving body moving direction, 203: imaging area, 204: scanning start point for camera imaging area, 205: scanning end point for camera imaging area, 301: output timing controller Control section, 303... Synchronization generation circuit, 306 ... Counter, 307 ... Crystal oscillator, 308 ... Register, 408 ... Video output signal for image pickup of the entire area of the camera, 501 ... Recognition target vehicle, 502 ... License plate, 503 ... Moving direction, 504 ... Detection area, 505 ... Recognition area, 506: Camera unit, 507: Prop, 701, 703, 801, 803: Detection area imaging time, 702, 704, 802, 804, 902, 904: Detection processing time, 705, 805: Recognition area imaging time, 706, 806, 905: recognition processing time, 707: vertical synchronization interval for capturing the entire imageable area of the camera, 708: time axis, 709, 710, 711, 807, 808, 809, 908, 909, 910: image memory Input image, 901, 903: imaging time, 906, 907: video memory input image, 9 5 ... Delete line.

Claims (1)

An image recognition apparatus for recognizing a moving object, comprising: a camera capable of externally inputting a synchronization signal timing defining a start point of field scanning at an arbitrary timing; and an output timing controller generating the synchronization signal timing. A detection unit for detecting the presence or absence of a moving object, performing the synchronization signal timing interval at intervals shorter than one field in detecting the presence or absence of a moving object, and detecting the presence or absence of the moving object in recognition of a moving object. An apparatus for recognizing a moving object, wherein the synchronization is performed at an interval longer than a time interval, and an interval of the synchronization signal timing is variable.

Images