JP2008113412A - Camera and monitoring device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera and a monitoring device or system using it, which can prevent a flicker without reducing light energy per image and losing trackability to a mobile unit. <P>SOLUTION: The camera and monitoring device are provided with a camera for photographing an image by a light with a wavelength different from that of a visible light. By correcting an image photographed by a visible light based on an image photographed by a light with a wavelength different from that of a visible light, stable monitoring is made possible. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a camera in which occurrence of flicker (flicker) is suppressed and a monitoring device or a monitoring system using the camera.

  In recent years, facilities for installing video surveillance devices using cameras (surveillance cameras) are increasing in order to record and deter criminal facts. A general video monitoring apparatus is composed of a camera, a recording device for video recording, and a monitor for video confirmation, and is often installed on the ceiling of the entrance / exit inside the facility or the wall of the entrance / exit outside the facility. By using such a system, it is monitored that there is no entry / exit of a suspicious person or stay.

  Furthermore, even in ordinary households, there are many cases where an intercom is provided for a visitor to call a resident. If the visitor uses the doorbell button provided on the intercom, the resident is notified that the visitor has arrived, and can be prompted to unlock the entrance door. In recent years, an interphone equipped with a camera so that a resident can confirm the appearance of a visitor in advance has been sold.

  A typical surveillance camera takes 60 images per second and transmits them to a recording device or a display device. Since the reaction speed of the human eye is limited, shooting a large number of images in this way and displaying them continuously allows them to be perceived as a smooth moving image.

  However, because of the property of capturing 60 images per second, flickering of images called flicker may be observed depending on the nature of the illumination.

  The most typical illumination that causes flicker is a fluorescent lamp. Fluorescent lamps discharge in response to fluctuations in electricity, and generate ultraviolet rays by colliding with the electrons generated by the discharge and the mercury source in the tube. Light is emitted when the ultraviolet rays collide with the fluorescent material. That is, the intensity of light is strongly influenced by the frequency of the power source. As is well known, in Japan, the frequency of the AC power supply in western Japan is 60 Hz, and the frequency of eastern Japan is different from 50 Hz. In the world, the frequency of the power supply is different in each country. For example, 60 Hz is mainly used in the United States, and 50 Hz is mainly used in Europe.

  FIG. 3 simply shows the cause of flicker. In Japan, flicker is observed in eastern Japan where the frequency of the AC power supply is 50 Hz. The camera shoots at 60 Hz (shoots 60 times per second), and the light emitted from the fluorescent lamp fluctuates so that one cycle is 1/50 seconds as shown in FIG. 201 in the figure represents the energy of light in a pseudo triangle, and the energy of the light emitted from the fluorescent lamp changes at each time as the power source changes with a sine wave. Ideally, the emission of light energy is a sine wave, but in reality it is not a beautiful sine wave, and forms a slightly distorted mountain. However, here, the principle is explained, and a triangular wave like 201 is considered.

  FIG. 3 also shows how the energy of light changing at 50 Hz is divided in 1/60 second. For example, 202, 203 is captured in the first 1/60 seconds, and 204, 205, 206 are captured in the next 1/60 seconds. That is, the total light energy of 202 and 203 is acquired in the first image, whereas the total light energy of 204, 205, and 206 is acquired in the next image.

  Further, in FIG. 3, what is indicated by 207 is a figure in which 204 and 206 are superimposed on 203. Since the light energy of 202 and 205 is the same in the first image and the next image, the difference in light energy contained in the first image and the next image can be seen by looking at 207. As can be seen from 207, the area of 203 is clearly larger than the total area of 204 and 206, so that the first image acquires more light energy than the next image. That is, the first screen is brighter than the next screen.

  Similarly, it is clear that this occurs when the light energy changes at 50 Hz and does not occur when it changes at 60 Hz.

  Conventionally, as a technology to prevent flicker, the light that is captured in each image is increased by increasing the shooting speed of the camera to 100 Hz, which corresponds to the shooting speed of 100 times per second, and shooting at a timing synchronized with 60 Hz. There are known methods for stabilizing the energy. That is, the camera internally generates a 60 Hz signal and a 100 Hz signal, and controls the image sensor so as to capture light only for one period of the 100 Hz signal from the start time of one cycle of the 60 Hz signal. With this configuration, as is apparent from FIG. 3, even when the power supply frequency is 50 Hz, the amount of light included in one imaging result is constant, and flicker is suppressed.

  If it is assumed that the object to be photographed is stationary, the energy of light contained in one image can be stabilized by regarding the average value of a plurality of images as one image.

  Moreover, in patent document 1, the light of a several different wavelength is observed and the imaging result of the light of a wavelength with the largest luminance value is used as an output image among them.

JP 2004-185109 A

  However, in the method of increasing the number of shootings per second, the energy of light per image decreases, so the brightness of the screen becomes dark, and in the method of considering the average value of multiple images as one image, In order to cope with a substantial decrease in shooting speed, a lot of afterimages appear when a moving object enters the screen, which is not desirable for monitoring purposes.

  The present invention provides a camera capable of preventing flicker without reducing light energy per image and without losing followability to a moving object, and a monitoring apparatus or a monitoring system using the camera. With the goal.

  In order to solve the above problems and to provide a camera and a monitoring device or monitoring system using the camera that have achieved the object, the camera and the monitoring device or monitoring system of the present invention include a camera that captures an image of visible light, The visible light image is corrected based on a camera that captures an image of light having a wavelength different from that of visible light (different from that of a fluorescent lamp) and an image of light having a wavelength different from that of the visible light.

  FIG. 1 shows the configuration of a general monitoring device. In the booth 10, a device 11 to be monitored is installed. A fluorescent lamp 102 and a surveillance camera 12 are attached to the ceiling 101 of the booth 10. An image taken by the monitoring camera 12 is delivered to the video storage device 14 and the video monitoring device 15 through the cable 13. Connected to the video monitoring device 15 is a display device 16 for displaying an image of the monitoring camera 12, an alarm from the video monitoring device 15, and the like. The order of connection between the video storage device 14 and the video monitoring device 15 is an example, and the video storage device 14 is not necessarily required to be connected in the order shown in FIG.

  FIG. 2 shows the internal structure of the conventional video monitoring apparatus 15 in more detail. The image from the monitoring camera 12 is sent to the analysis device 1501 which is the main body of the monitoring function through the image input terminal 1500. The analysis device 1501 appropriately analyzes the input image and sends the result to the output generation device 1502. Here, the analysis device 1501 generally performs a comparison between the input image and the image accumulated in the past, and if there is a difference to be noticed, the output generation device 1502 notifies that fact as an alarm. It is a process of sending. To that end, the analysis device 1501 has some video storage means to store past images or to perform processing such as extracting past images by communicating with the video storage device 14. There is. In the output generation device 1502, for example, if there is no alarm from the analysis device 1501, the input image is output as it is to the external monitor 16 or the like through the output terminal 1503, or if there is an alarm from the analysis device 1501, a video to that effect is displayed. The sound is output to the outside through an output terminal 1503.

  An example of the monitoring apparatus of the present invention is shown in FIG. In the monitoring device of FIG. 4, a device 11 to be monitored is installed in the booth 10. On the ceiling 101 of the booth 10, a fluorescent lamp 102, an infrared light generator 103, and a plurality of monitoring cameras 12 and 17 are installed. Here, the fluorescent lamp 102, the infrared light generator 103, and the monitoring cameras 12 and 17 are not necessarily installed on the ceiling 101. That is, as long as the monitoring target can be appropriately lit up and an image can be acquired, it may be installed on a wall surface or the like, and the installation location is not limited. Here, 103 is an infrared light generator, but it is not necessary to limit to infrared light as long as the light has a wavelength different from that of visible light emitted from the fluorescent lamp 102.

  In this embodiment, the monitoring camera 12 is a camera that captures visible light, and the monitoring camera 17 is a camera that captures infrared light. Of course, since the surveillance camera 17 is intended to capture the light of the infrared light generator 103, if 103 is light of a wavelength other than infrared light (of course, other than visible light), A camera having a suitable imaging system may be replaced. As is well known, if a filter that passes only a specific wavelength is used in the A / D converter portion of the camera, a camera that captures light of a required wavelength can be configured. It is assumed that the frequency of the power source of the fluorescent lamp 102 and the number of imaging per second of the monitoring camera 12 are different. The infrared light generator 103 does not depend on the frequency of the power source. That is, the light emission method using the characteristics of the DC power supply is used instead of the light emission method using the characteristics of the AC power supply. Or even if it is the light emission system using the characteristic of an alternating current power supply, a system with almost no fluctuations in illuminance at each time, such as an incandescent lamp that emits light by heating a filament, is used. Actually, the incandescent lamp emits infrared light, and the incandescent lamp can be used as the infrared light generator 103. In this case, light of a component such as visible light other than light having a wavelength used for image correction in the present application (for example, infrared light) generated from an incandescent lamp is not used for image correction. There is no particular problem in configuring the system. Further, as the infrared light generator 103, a halogen lamp which is a kind of incandescent lamp can be used. Compared with incandescent lamps of the same wattage, halogen lamps can be made compact with a volume of about 1/200, and have a property that a light emission life of about twice can be obtained. The halogen lamp includes a filament made of tungsten. When a current flows through the filament, tungsten is incandescent and emits light. In the filament system, there is almost no fluctuation in illuminance at each time, so that flickering is not induced like a fluorescent lamp.

  In the present embodiment, images taken by the monitoring cameras 12 and 17 are sent to the video storage device 14 and the monitoring device 18 through the cable 13. Further, the output of the monitoring device 18 is sent to the display device 16. The cable 13 is often a coaxial cable, but in recent years there are many surveillance cameras that can be directly connected to an IP network, and the cable 13 may be a LAN cable. In addition, there is a possibility that the cable conforms to a special specification, but any of them does not prevent application of the present invention.

  The configuration of the video monitoring apparatus 18 of the present invention is different from the conventional video monitoring apparatus 15 shown in FIG. The configuration of the video monitoring apparatus of the present invention is shown in FIG. As shown in FIG. 5, the video monitoring device 18 of the present invention includes a correction information calculation device 1504, a correction device 1506, and a second analysis device 1507 in addition to the conventional first analysis device 1501 and output generation device 1508. Prepare. Hereinafter, it is assumed that an image obtained by photographing visible light is output from the first camera 12, and an image obtained by photographing infrared light is output from the second camera 17.

  The video monitoring apparatus 18 according to the present invention captures, in the correction information calculation apparatus 1504, images taken at the same time or close times from the first camera 12 and the second camera 17 in order to create correction information 1505. As shown in FIG. 8, since flicker occurs in one acquired image, the relative brightness of the image 401 from the first camera 12 and the image 402 from the second camera 17 is different at most times. Therefore, remember the relative brightness difference between the image of the camera 17 that does not vary in brightness and the image (401) of the reference camera 12, as shown below. If the 12 images are darker than the reference, the image is corrected to be bright, and if it is bright, the image is corrected to be dark.

  The correction information calculation device 1504 compares the image 401 from the first camera with the image 402 from the second camera, and at a later time, the image 403 from the first camera and the image 404 from the second camera. , Correction information 1505 is calculated so that the correction device 1506 can correct the image 403 so that the image 403 has the same brightness as the image 401. The simplest correction information for realizing the above function is a difference value between the image 401 and the image 402. If there is a reference difference value, the brightness of the image from the first camera can be corrected under the assumption that the brightness of the images 402 and 404 from the second camera is stable. That is, paying attention to a certain area in the image, it is confirmed whether or not the difference value between the image 403 and the image 404 matches the difference value of the correction information. The pixel value is corrected.

  Here, it is assumed that the images 401 and 403 are images obtained by capturing visible light, but the image of the camera that captures visible light is often further processed by being divided into three components of red, green, and blue. Even in this monitoring apparatus, it is possible to perform correction with higher accuracy by generating the correction information 1505 for each of the three components. Of course, it is not necessary to be limited to the above three components, such as the YUV format expressed by the luminance signal (Y), the difference between the luminance signal and the blue component (U), and the difference between the luminance signal and the red component (V). Needless to say, correction information may be created. Furthermore, in calculating the difference value, if the average value of the brightness of the pixels at the surrounding coordinates is used instead of the pixels at the same coordinates, the influence of the thermal noise appearing in the imaging system is reduced. be able to.

  Here, an example in which the correction information 1505 is calculated based on the images 401 and 402 has been described, but the image captured by the first camera 12 includes flicker, as seen in 301, 303, and 305 in FIG. The brightness changes with the shooting time. Therefore, the monitoring device 18 has means for selecting an image to be input to the correction information calculation device 1504, and generates the correction information 1505 when the image from the first camera 12 is brightest. It is also possible to perform adjustment so that an image suitable for use in the apparatus 1501 can be obtained.

  The monitoring system of the present invention can achieve the expected effect even if the shooting times of the first monitoring camera and the second monitoring camera are slightly shifted, but the correction effect is highest when they are completely synchronized. The monitoring device 18 illustrated in FIG. 6 further includes a synchronization signal generation device 1510, and transmits a synchronization signal from the synchronization signal output terminal 1511 to the first camera 12 and the second monitoring camera 17. The first monitoring camera 12 and the second monitoring camera 17 can perform shooting at the same time by performing shooting according to the received synchronization signal. The synchronizing signal generally uses 60 Hz, but is not necessarily limited to 60 Hz. On the other hand, it is also possible to generate a synchronization signal from the frequency of the AC power supply, and in that case, it is not necessary to send the synchronization signal from the monitoring device 18. However, since synchronization is not guaranteed for a plurality of AC power supply cycles, the method using the synchronization signal from the monitoring device 18 is more reliable.

  An example of the correction information calculation method will be described. When the image X1 of the first camera and the image X2 of the second camera for correction information calculation are obtained, the vector A is calculated assuming that X1 = A * X2. That is, x1 [i, j] = a [i, j] * x2 [i, j] for the pixel values x1 [i, j] and x2 [i, j] at the coordinates of X1 and X2 Calculate a [i, j]. This a [i, j] is the correction information. Note that i, j is a variable representing the x-coordinate and y-coordinate positions of the photographed image, and a [i, j] is correction information corresponding to the image coordinates (i, j). In this example, the correction information held in the video correction device is the value of a [i, j] for all coordinates.

  Next, an example regarding the correction method is shown. When the image X3 of the first camera and the image X4 of the second camera are obtained, the vector B is calculated assuming that X3 = B * X4. That is, x3 [i, j] = b [i, j] * x4 [i, j] is obtained for the pixel values x3 [i, j] and x4 [i, j] at the coordinates of X3 and X4. b [i, j] is calculated. b [i, j] is compared with a [i, j] as correction information, and if it is determined that the values are close, the value of x3 [i, j] is used as it is. If b [i, j] and a [i, j] are different, correction is made as x3 [i, j] = a [i, j] * x4 [i, j]. In this embodiment, since X3 is a visible light image (R, G, B) and X4 is an infrared light image (grayscale), x3 [i, j] is decomposed into R, G, B and x3R [ i, j], x3G [i, j], x3B [i, j] may be corrected independently using x4.

  Although an example of simple correction has been described above, the number of images used to create correction information is not necessarily limited to one (one set), and a plurality of images may be used. By using a plurality of images, it is possible to create more complicated correction information such as using the difference between the difference between the first camera image and the second camera image at different times as the correction information. Depending on the relationship between the blinking interval of visible light illumination and the shooting interval, the difference D (t) between the image of the first camera and the image of the second camera at time t and the similar difference D (t at the next time t + 1 In some cases, the difference absolute value | D (t + 1) −D (t) | of +1) may be constant. In such a case, the correction information can be made more compact. Further, it is needless to say that the correction information is not only generated once at the beginning, but may be recreated or updated every time an image is input.

  FIG. 9 shows an embodiment in which the video correction device 20 and the video monitoring device 21 are independent. The video monitoring apparatus 21 of the present embodiment receives as an input an image which is an output of the video correction apparatus 20 and is a result of correcting an image obtained from the first camera by the second camera and an image of the second camera. . As shown in FIG. 10, images acquired by the first camera and the second camera are transmitted to the video correction device 20. When the generation of the correction information is instructed, the video correction device generates the correction information from the two input images and holds it inside. When generation of correction information is not instructed, the video correction apparatus combines one of the two input images and the correction information held therein to correct one image and outputs two images. The image output here is transmitted to the video monitoring device 21 installed at the subsequent stage of the video correction device 20. The video monitoring device 21 analyzes the input image and outputs the result.

  FIG. 10 shows an example of a video correction device equipped with a synchronization signal generation device for synchronizing the shooting timings of the first camera and the second camera, but this function is not necessarily essential, By using such a synchronization signal, correction can be performed with higher accuracy. Further, the synchronization signal generation device does not need to be built in the video correction device, and may exist as an independent module or may be installed in the video monitoring device.

  The video correction device 20 and the video monitoring device 21 shown in FIG. 11 further include a synchronization signal output terminal 1512 and a synchronization signal input terminal 1513 which are terminals for inputting and outputting a synchronization signal in addition to FIG. The output of the synchronization signal generator is configured to be output through the synchronization signal output terminal 1512 when the two images are output simultaneously at the end of the correction in the video correction device 20, and received by the video monitoring device 21 from the synchronization signal input terminal 1513. Has been. The video monitoring device 21 receives the synchronization signal from the synchronization signal input terminal 1513, determines that an image is output from the video correction device 20 at the same time, and the first analysis device 1501 and the second analysis device 1507. Enter an image in. Receiving the image input, the first analysis device 1501 and the second analysis device 1507 each perform processing such as suspicious object detection and output an analysis result.

  4, 5, 6, 9, 10, and 11, the configuration including the monitoring camera 12 for visible light imaging and the monitoring camera 17 for infrared light imaging is shown, but it is not always necessary to prepare two cameras. .

  FIG. 12 shows an example of a monitoring device using a monitoring camera 19 that can simultaneously perform imaging of visible light and infrared light with a single unit. The internal structure of the surveillance camera 19 is shown in FIG. The surveillance camera 19 receives incident light 1900 with a lens 1901 and separates it into visible light 1903 and infrared light 1905 using a prism 1902 provided therein. Visible light 1903 is captured by a visible light camera or A / D converter 1904, and infrared light 1905 is captured by an infrared light camera or A / D converter 1906, and output from output terminals 1907 and 1908, respectively. Is done. If these output terminals 1907 and 1908 are read as the first monitoring camera 12 and the second monitoring camera 17 in FIGS. 4, 5, 6, 9, 10, 11, one monitoring camera may be provided.

  FIG. 14 shows a monitoring device to which the present invention is applied that is inherent in the device 2004 to be monitored. The monitoring apparatus of the present embodiment includes a video correction monitoring apparatus 20005, a display apparatus 2006, and a first camera 2001, a second camera 2002, a video correction apparatus, and a monitoring apparatus that are incorporated in the monitoring target 2004. The illumination device 2003 includes only an invisible light source having a wavelength that can be imaged by the second camera 2002 or a visible light source having a wavelength that can be imaged by the first camera 2001.

  The first camera 2001 and the second camera 2002 are connected to the video correction monitoring apparatus 2005 using data transmission cables 2008 and 2009. The display device 2006 is connected to the image correction monitoring device 2005 using a display content transmission cable 2007. The monitoring apparatus of this embodiment is space-saving, can set a monitoring area in detail, and can finely adjust for each monitoring target.

  The first camera 2001 transmits the imaging data to the video correction monitoring apparatus 2005 through the data transmission cable 2008. The data to be transmitted is not necessarily limited to only the imaging data, and additional data such as shooting time information and exposure settings of the imaging data can be sent together. In addition, information such as a command or parameter for instructing exposure adjustment may be sent from the image correction monitoring apparatus 2005 to the first camera 2001. When priority is given to downsizing the camera, the adjustment function and the number of acquired data may be limited, and only imaging data may be sent.

  The second camera 2002 also exchanges data through the data transmission cable 2009 in the same manner as in the case of the first camera. The display device 2006 receives and displays the video information generated by the video correction monitoring device 2005 for display via the display content transmission cable 2007.

  In this embodiment, the display device 2006 is also used as an information display device for the monitoring target 2004, and the processing result of the monitoring device is displayed at one timing and the processing result of the monitoring target is displayed at another timing. It is assumed that the display device is used by dividing the screen into a plurality of screens. For this reason, the video correction monitoring apparatus 2005 also serves as an information processing apparatus for the monitoring target 2004, and only one display data transmission cable 2007 is connected to the display apparatus 2006.

  When the image correction monitoring device 2005 and the information processing device of the monitoring target 2004 are separately provided, a new display data transmission for connecting the information processing device of the monitoring target 2004 and the display device is provided separately from the display data transmission cable 2007. Use cables. These two cables may be connected to the display device 2006 with two receptacles, or the data transmission cable from the information processing device 2004 to be monitored is once connected to the video correction monitoring device 2005 The final display data may be transmitted to the display device 2006 by the display data transmission cable 2007 after appropriately selecting and combining the display data.

  An example in which the positions of the first camera and the second camera are installed at the positions shown in FIG. 14 so that the front panel of the monitoring target 2004 can be monitored is shown. However, when the location to be monitored is limited in the monitoring target 2004 or when monitoring other than the front panel is desired, the installation location is not necessarily limited to the illustrated location.

  Moreover, although the example which separated and installed the 1st camera and the 2nd camera was shown, it does not necessarily need to isolate | separate and you may install adjacent to one place. Further, the functions of the first camera and the second camera may be integrated in one box. The monitoring apparatus of the present embodiment uses the video correction monitoring apparatus 2005 in which the video correction apparatus and the monitoring apparatus are integrated because of the requirement for space saving due to the built-in, but it is not always necessary to use a single apparatus.

  The lighting device 2003 is installed above the monitoring target 2004. However, the lighting device 2003 only needs to be able to illuminate the monitoring target part, and is installed at a lower position depending on the shape of the monitoring target 2004. Further, the lighting device 2003 is not necessarily limited to one, and a plurality of lighting devices may be provided.

  FIG. 15 shows an example in which the lighting device 2003 is housed in a camera housing 2103. By arranging the light source 2102 around the lens 2101 of the camera, a monitoring device can be configured without installing special illumination on the monitoring target 2004.

  If a visible light source is already installed outside the monitoring device, a camera with only an invisible light source may be used. Further, only one of the first camera and the second camera may be a camera with a built-in light source.

  FIG. 16 shows an embodiment in which a camera with a built-in light source is used. A light source is incorporated in one or both of the first camera 2201 and the second camera 2202, and the monitoring target 2203 is imaged. The image correction monitoring device 2204 performs monitoring using the imaging data. In this embodiment, since it is not necessary to attach illumination to the monitoring target 2203, it is more suitable when the monitoring device is installed later.

By using the camera and the monitoring device or the monitoring system of the present invention, it is possible to acquire a stable monitoring image and perform stable monitoring even in regions having different power supply frequencies.

General monitoring system configuration. General monitoring device configuration. Explanatory drawing of the generation principle of flicker (flicker). The structure of the monitoring system of this invention. The structure of the monitoring apparatus of this invention. The structure of the monitoring apparatus of this invention which has a synchronizing signal production | generation apparatus. Explanatory drawing of the image acquired with the monitoring system of this invention. Explanatory drawing of the image correction in the monitoring apparatus of this invention. 2 is a configuration example of a camera used in the monitoring system of the present invention. The structure of the monitoring apparatus of this invention which has a synchronizing signal production | generation apparatus and divided | segmented the video correction part and the video monitoring part. The structure of the monitoring apparatus of this invention which synchronizes a video correction | amendment part and a video monitoring part with a synchronizing signal. A configuration of a monitoring device including a monitoring camera capable of simultaneously capturing visible light and infrared light with a single unit. A surveillance camera configuration that can capture visible light and infrared light at the same time. The structure of the monitoring apparatus of this invention incorporated in the monitoring object. Explanatory drawing of the camera which incorporated the light source. The structure of the monitoring apparatus of this invention using the camera which incorporated the light source.

Explanation of symbols

  10: Booth to be monitored, 11: Monitored object, 12: First surveillance camera, 13: Cable, 14: Video recording device, 15: Video surveillance device, 16: Monitor, 17: Second surveillance camera, 18 : Video correction monitoring device of the present invention, 19: Camera that outputs multiple images from light of multiple wavelengths, 20: Video correction device, 21: Video monitoring device, 101: Ceiling of booth to be monitored, 102: Monitoring target Booth fluorescent lamp, 103: Infrared illumination of the booth to be monitored, 201, 202, 203, 204, 205, 206: Schematic diagram representing the temporal change of light energy, 207: Overlaid diagram of 203, 204, 206, 301, 303, 305: First camera at each time Output image, 302, 304, 306: Output image of second camera at each time, 401: Output image of first camera as reference, 402: Output image of second camera as reference, 403: First image at a certain time Camera output image, 404 at a certain time Second camera output image, 405: corrected first camera output image, 1500: first image input terminal, 1501: first monitoring device, 1502: output generation device, 1503: video monitoring device Image output terminal, 1504: Correction information calculation device, 1505: Correction information, 1506: Correction device, 1507: Second monitoring device, 1508: Output generation device, 1509: Second image input terminal, 1510: Synchronization signal Generator, 1511.1512: synchronization signal output terminal, 1513: synchronization signal input terminal, 1900: light incident on the camera, 1901: lens receiving incident light, 1902: prism for separating light of different wavelengths, 1903: first wavelength 1904: Camera that shoots light of the first wavelength, 1905: Light of the second wavelength, 1906: Camera that shoots light of the second wavelength, 1907: Camera that shoots light of the first wavelength Image output terminal, 1908: Image output terminal of the camera that captures light of the second wavelength. 2001, 2002, 2201, 2202: Surveillance camera, 2003: Lighting device, 2004, 2203: Device to be monitored, 2005, 2204: Video correction monitoring device, 2006: Display device, 2007: Display content transmission cable, 2008, 2009 : Data transmission cable, 2101: Lens, 2102: Light source, 2103: Camera housing.

Claims (12)

A monitoring device having first and second imaging means for imaging at a predetermined frequency, a video correction unit, and a video monitoring unit,
The first and second imaging means capture images of substantially the same region,
The first imaging means captures an image of the region in a first wavelength region and outputs a first image;
The second imaging means captures an image of the region in the second wavelength region and outputs a second image,
The video correction unit corrects the luminance of the first image based on the luminance of the second image,
The monitoring apparatus, wherein the video monitoring unit performs the monitoring process of the area using the first image with the corrected brightness and the second image.   2. The monitoring apparatus according to claim 1, wherein the first wavelength region is a visible light wavelength region, and the second wavelength region is an infrared light wavelength region.   2. The monitoring apparatus according to claim 1, wherein the first imaging unit performs imaging using light in the first wavelength region by a first light source whose brightness varies with a first frequency, The imaging device performs imaging with light in the second wavelength region by a second light source whose brightness does not vary within a predetermined frequency for performing the imaging.   4. The monitoring apparatus according to claim 3, wherein the first light source is a fluorescent lamp, and the second light source is an LED or a halogen lamp.   4. The monitoring apparatus according to claim 3, wherein the predetermined frequency and the first frequency are different.   The monitoring apparatus according to claim 1, wherein the first and second imaging units are first and second cameras.   2. The monitoring apparatus according to claim 1, wherein the first and second imaging units use a prism to convert light incident from the same lens into light in the first wavelength region and light in the second wavelength region. 3. And a first imaging unit for capturing and outputting the first and second images, respectively.   The monitoring apparatus according to claim 1, wherein the first imaging unit and the second imaging unit are controlled to synchronize imaging timing.   9. The monitoring apparatus according to claim 8, wherein the first imaging unit and the second imaging unit send a synchronization signal in order to synchronize the imaging timing of the first imaging unit and the second imaging unit. A monitoring device characterized by receiving.   The monitoring device according to claim 1, wherein the video monitoring device performs suspicious object detection using the first and second images taken by the first and second imaging means at a plurality of times. A monitoring device characterized by that.   2. The first imaging unit, the second imaging unit, the video correction unit, and the video monitoring unit are located outside an object to be imaged by the first imaging unit and the second imaging unit. Monitoring device.   The first imaging means, the second imaging means, the video correction unit, and the video monitoring unit are inherent in an object imaged by the first imaging means and the second imaging means. Monitoring device.

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