JP2019092172A - Dynamic body monitoring device and dynamic body monitoring system - Google Patents

Abstract

To output an appropriate composite color image, in which the actual color of a subject appears clearly, according to the situation of ambient light, by a low cost configuration.SOLUTION: A dynamic body monitoring device includes a color camera 11 for shooting a monitoring area by ambient light, a monochrome camera 12 for shooting the monitoring area by infrared radiation, a signal processing section 21 for processing a color image outputted from the color camera and a monochromatic image outputted from the monochrome camera, and an image composition section for acquiring color information from the color image, and performing the coloring of the monochromatic image by using the color information. The signal processing section has a resolution conversion section 54 for reducing the number of pixels of the color image, by adding the signal values of each of multiple pixels close to each other in the color image, a signal level detector 52 for detecting the signal level of the color image, and a signal processing control section 53 for controlling operation of the resolution conversion section on the basis of the signal level.SELECTED DRAWING: Figure 4

Description

  The present invention provides a moving object monitoring apparatus that outputs an image obtained by capturing an image of a monitoring area in which a moving object to be monitored appears, and a moving object monitoring system that transmits an image obtained by capturing the monitoring area from the moving object monitoring apparatus to an image storage apparatus via a network. It is about

  2. Description of the Related Art A monitoring system for monitoring the condition of a moving object such as a person to be monitored by installing a camera for photographing a monitoring area is widely spread. In such a monitoring system, in order to be able to continue monitoring even at night, a camera may be used which irradiates infrared light to a subject and shoots the subject.

  In such photographing by infrared light, while a clear image can be obtained, it becomes a monochrome image, so the color of the subject can not be determined. In particular, there is a problem in that false recognition of a moving object to be monitored occurs because the blue clothes of a person appear white, for example, when the luminance is reversed. Therefore, there is a need for a technology that enables the color of an object to be determined even in an image captured at night.

  In response to such a request, the subject is photographed with infrared light, and the subject is irradiated with visible laser light corresponding to the three primary colors in a predetermined projection pattern, and the color information of the subject based on the intensity of the reflected light of each color. There is known a technique for acquiring an image and coloring the infrared image using the color information (see Patent Document 1).

JP, 2013-219560, A

  However, in this prior art, although an image capable of determining the color of the subject can be obtained, it is necessary to use an expensive laser light source to irradiate the laser light, which causes a problem that the manufacturing cost of the device increases. there were.

  Therefore, the present invention provides a moving object monitoring apparatus and a moving object monitoring system capable of outputting an appropriate color image in which the actual color of an object clearly appears according to the environment light conditions with a low cost configuration. The main purpose is to

  A moving object monitoring apparatus according to the present invention is a moving object monitoring apparatus which combines and outputs a color image and a monochrome image obtained by capturing a monitoring area in which a moving object to be monitored appears, and a color camera capturing the monitoring area with ambient light; A monochrome camera for photographing the monitoring area with infrared light, a signal processing unit for processing the color image output from the color camera and the monochrome image output from the monochrome camera, color information from the color image And an image combining unit for performing processing to color the monochrome image using the color information, the signal processing unit adds signal values for each of a plurality of pixels adjacent in the color image, and A resolution converter for reducing the number of pixels of the color image, and an operation of the resolution converter based on the shooting environment of the monitoring area. And a signal processing control unit Gosuru, configured to have a.

  Further, according to the moving object monitoring system of the present invention, a moving object monitoring system transmits a color image and a monochrome image obtained by photographing a monitoring area in which a moving object to be monitored appears in the moving object monitoring apparatus from the moving object monitoring apparatus to the server apparatus via the network. In the system, the moving object monitoring device includes a color camera that captures the monitoring area with ambient light, a monochrome camera that captures the monitoring area with infrared light, the color image output from the color camera, and The server apparatus includes: a signal processing unit that processes the monochrome image output from the monochrome camera; and a communication unit that transmits the color image and the monochrome image processed by the signal processing unit to the server device. Acquiring color information from the signal of the color image, and using the color information, the monochrome image The image processing apparatus further includes an image combining unit that performs processing for coloring a signal, and the signal processing unit further performs signal conversion for reducing the number of pixels of the color image by adding signal values for each of a plurality of adjacent pixels in the color image. And a signal processing control unit configured to control an operation of the resolution conversion unit based on a photographing environment of the monitoring area.

  According to the present invention, in a situation where there is a slight amount of ambient light, the actual color information of the subject is included in the signal value of each pixel, so by adding the signal values of a plurality of pixels, the actual color of the subject is determined. It is possible to output a composite color image that appears clearly. In addition, since the operation of the resolution conversion unit is controlled based on the signal level, that is, the brightness of the ambient light, an appropriate composite color image can be output regardless of the status of the ambient light. In addition, since expensive parts such as a laser light source are unnecessary, the manufacturing cost can be reduced.

The whole block diagram of the moving body monitoring system concerning this embodiment Explanatory drawing which shows the imaging condition by the camera apparatus 1. Block diagram showing a schematic configuration of the camera device 1 Functional block diagram showing a schematic configuration of the signal processing unit 21 Explanatory drawing which shows the point of the resolution conversion performed by the resolution conversion part 54 An explanatory view showing a histogram before and after resolution conversion Explanatory drawing which shows the processing mode set by the signal processing control part 53. Flow chart showing the procedure of processing performed by the signal processing control unit 53 Flow chart showing the procedure of white balance correction performed by the gradation color tone correction unit 55 Explanatory drawing which shows the condition of the gradation correction | amendment performed by the gradation color tone correction | amendment part 55

  A first invention made to solve the above-mentioned problems is a moving object monitoring apparatus for combining and outputting a color image and a monochrome image obtained by photographing a monitoring area in which a moving object to be monitored appears, the monitoring area using environmental light A monochrome camera for shooting the monitoring area with infrared light; a signal processing unit for processing the color image output from the color camera and the monochrome image output from the monochrome camera; And an image combining unit for acquiring color information from the color image and performing processing for coloring the monochrome image using the color information, the signal processing unit including: for each of a plurality of pixels adjacent in the color image A resolution conversion unit that adds signal values to reduce the number of pixels of the color image; And a signal processing control unit for controlling the operation of the resolution conversion unit, configured to have a.

  According to this, in a situation where there is slight ambient light, the actual color information of the subject is included in the signal value of each pixel, so by adding the signal values of a plurality of pixels, the actual color of the subject becomes clear The composite color image that has appeared can be output. In addition, since the operation of the resolution conversion unit is controlled based on the signal level, that is, the brightness of the ambient light, an appropriate composite color image can be output regardless of the status of the ambient light. In addition, since expensive parts such as a laser light source are unnecessary, the manufacturing cost can be reduced.

  According to a second aspect of the present invention, a signal level detection unit for detecting the signal level of the color image is provided, and the signal level is referred to for determination of the photographing environment.

  According to this, appropriate resolution conversion can be performed according to the signal level of the color image.

  In the third invention, the signal processing control unit suspends the operation of the resolution conversion unit when it is determined that the signal level is equal to or higher than a predetermined threshold value.

  According to this, since resolution conversion does not need to be performed in a state where the signal level is sufficiently large, that is, there is sufficient ambient light, unnecessary processing can be avoided by omitting resolution conversion in such a case. it can.

  Further, in the fourth invention, the signal processing control unit compares the signal level with a plurality of threshold values, and based on the comparison result, the degree of resolution conversion in the resolution conversion unit is stepwise It will be a configuration to change.

  According to this, since the degree of resolution conversion is changed according to the signal level, that is, the brightness of the ambient light, saturation of the signal value can be suppressed, and an appropriate color image can be output.

  The fifth invention may further include an averaging reduction unit that performs reduction processing by averaging on the signal of the color image output from the resolution conversion unit, and the signal processing control unit performs the resolution conversion. The degree of averaging reduction in the averaging reduction unit is set according to the degree of resolution conversion in the unit so that the color image having the same size can be obtained.

  According to this, it is possible to output a color image of uniform size regardless of the degree of resolution conversion.

  A sixth aspect of the present invention is a moving object monitoring system for transmitting a color image and a monochrome image obtained by capturing a monitoring area in which a moving object to be monitored appears in a moving object monitoring device from the moving object monitoring device to a server device via a network. The moving object monitoring apparatus comprises a color camera for capturing the monitoring area with ambient light, a monochrome camera for capturing the monitoring area with infrared light, the color image output from the color camera and the monochrome camera A signal processing unit that processes the monochrome image output from the communication unit, and a communication unit that transmits the color image and the monochrome image processed by the signal processing unit to the server device, The color information is obtained from the signal of the color image, and the color information is used to color the signal of the monochrome image A resolution conversion unit configured to reduce the number of pixels of the color image by adding an image combining unit that performs processing on the color image, and the signal processing unit adding signal values of a plurality of pixels adjacent to each other in the color image; And a signal processing control unit configured to control an operation of the resolution conversion unit based on a photographing environment of the monitoring area.

  According to this, as in the first aspect of the invention, it is possible to output an appropriate composite color image in which the actual color of the subject clearly appears according to the situation of the ambient light with a low cost configuration.

  Further, according to a seventh invention, the communication unit adds imaging information including at least one of an installation place, a camera attribute, an imaging time, and an imaging condition to the color image and the monochrome image and transmits the information. .

  According to this, management of color images and monochrome images performed in the image storage device is facilitated, and shooting information can be presented to a user who browses the images.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an overall configuration diagram of a moving object monitoring system according to the present embodiment.

  The motion monitoring system includes a camera device 1 (motion monitoring device), a server device 2 (image storage device), and a browsing device 3. The camera device 1, the server device 2 and the browsing device 3 are connected via a network.

  The camera device 1 captures an image of a monitoring area set in a facility, a road, or the like, and outputs a captured image showing a moving object such as a person present in the monitoring area. The server device 2 accumulates captured images acquired from the camera device 1. The browsing device 3 is a PC, a tablet terminal, a smartphone, or the like, and by accessing the server device 2, the user can browse the photographed image stored in the server device 2.

  Next, the camera device 1 will be described. FIG. 2 is an explanatory view showing a photographing situation by the camera device 1.

  The camera device 1 includes a color camera 11 and a monochrome camera 12. The color camera 11 and the monochrome camera 12 capture an object present in the monitoring area, that is, a moving object such as a person, a building, a site of a facility, a road, and the like.

  The color camera 11 includes an infrared light cut filter, photographs a subject in color with visible light, and outputs a color image. The monochrome camera 12 includes a visible light cut filter, photographs a subject in monochrome with infrared light, and outputs a monochrome image. When photographing with the monochrome camera 12, near infrared light is emitted to the subject by the infrared light projector 13 (see FIG. 3).

  Here, when photographing is performed with the color camera 11 in a state where there is not enough ambient light at night, in a sunset or sunrise time zone, in a photographed color image, a moving object or a background serving as a subject appears dark. There is a problem that it is difficult to determine the color of a moving body, for example, the color of clothes of a person or the color of a vehicle body. In addition, in a monochrome image photographed by near-infrared light by the monochrome camera 12, there is a problem that the luminance is reversed, for example, the blue clothes of a person appear white. As a result, false recognition of the moving body occurs.

  Therefore, in the present embodiment, by performing signal processing on the color image signal output from the color camera 11, the actual color of the subject becomes clear even when the image is taken without sufficient ambient light. It makes it possible to generate a high quality color image that appears.

  In the present embodiment, the color camera 11 and the monochrome camera 12 are provided. However, one so-called day / night camera capable of switching the photographing mode between day and night may be provided. In this day-and-night camera, for example, by inserting and removing the infrared light cut filter, it is possible to switch between a mode for photographing a color image by visible light and a mode for photographing a monochrome image by infrared light.

  Moreover, although the example which made outdoor the monitoring area in FIG. 2 is shown, it is good also considering indoor indoors. In this case, the brightness of the ambient light of the monitoring area changes due to the lighting / lighting off of the lighting equipment in addition to the sunshine.

  Next, a schematic configuration of the camera device 1 will be described. FIG. 3 is a block diagram showing a schematic configuration of the camera device 1.

  The camera device 1 includes an infrared light projector 13, a communication unit 14, a control unit 15, and a storage unit 16 in addition to the color camera 11 and the monochrome camera 12.

  The infrared light projector 13 projects near infrared light onto the subject when the subject is photographed by the monochrome camera 12.

  The communication unit 14 communicates with the server device 2 via a network. In the present embodiment, the processed color image and monochrome image output from the control unit 15 are transmitted to the server device 2.

  At this time, shooting information regarding the installation location, camera attribute, shooting time, shooting conditions and the like is added to the color image and monochrome image as attribute information and transmitted. The camera attribute relates to whether color or monochrome, identification information (such as a MAC address) of the camera device 1 or the like. Also, the photographing conditions relate to the exposure time, the gain and the like.

  The character recognition process may be performed on the monochrome image to acquire character information in the monochrome image, and the character information may be added to the monochrome image.

  The storage unit 16 stores color images and monochrome images generated by the control unit 15. The storage unit 16 also stores a program executed by the control unit 15.

  The control unit 15 includes a signal processing unit 21 and an LED control unit 22. The control unit 15 is configured by a processor, and each unit of the control unit 15 is realized by executing a program stored in the storage unit 16.

  The signal processing unit 21 processes image signals respectively output from the color camera 11 and the monochrome camera 12.

  The LED control unit 22 controls an LED serving as a light source of the infrared light projector 13.

  Next, the signal processing unit 21 will be described. FIG. 4 is a functional block diagram showing a schematic configuration of the signal processing unit 21. As shown in FIG.

  The signal processing unit 21 includes a synchronization signal generation unit 31, a monochrome signal processing unit 32, and a color signal processing unit 33.

  The synchronization signal generator 31 generates a synchronization signal for synchronizing the color camera 11 and the monochrome camera 12. By this synchronization signal, the color camera 11 and the monochrome camera 12 can capture an object at the same timing.

  The monochrome signal processing unit 32 includes a camera interface 41, a tone correction unit 42, and a gamma correction 43.

  The camera interface 41 receives an image signal of a monochrome image output from the monochrome camera 12.

  The tone correction unit 42 performs tone correction on the image signal of the monochrome image input to the camera interface 41.

  The gamma correction unit 43 performs gamma correction on the image signal output from the gradation correction unit 42 so as to correct the gradation of the image to an optimum characteristic according to the characteristic of the display device.

  The color signal processing unit 33 includes a camera interface 51, a signal level detection unit 52, a signal processing control unit 53, a resolution conversion unit 54, a gradation color tone correction unit 55, a gamma correction unit 56, and Y component generation. A unit 57, a UV component generation unit 58, and an averaging reduction unit 59 are provided.

  The camera interface 51 receives an image signal of a color image output from the color camera 11.

  The signal level detection unit 52 detects a signal level based on the image signal of the color image input to the camera interface 51. This signal level represents the brightness of the entire image which is the shooting environment of the monitoring area, that is, the brightness of the ambient light of the monitoring area, and is detected based on the maximum value of brightness and the distribution state (histogram) .

  The signal processing control unit 53 sets the degree (reduction ratio) of resolution conversion performed by the resolution conversion unit 54 with reference to the signal level obtained by the signal level detection unit 52. Further, the signal processing control unit 53 sets the degree (reduction ratio) of averaging reduction performed by the averaging reduction unit 59 according to the degree of resolution conversion. Note that the degree of resolution conversion includes the case where the operation of the resolution conversion unit 54 is stopped and resolution conversion is not performed, and the degree of averaging reduction is performed by stopping the operation of the averaging reduction unit 59. It also includes the case where averaging reduction is not performed. Here, the degree of resolution conversion (reduction ratio) performed by the resolution conversion unit 54 is set based on the signal level acquired by the signal level detection unit 52 as the shooting environment of the monitoring area. It is also possible to omit the part 52 and maintain a control table for setting the degree of resolution conversion for each time zone (one or more) of night time according to the setting of daytime and nighttime set for each day .

  The resolution conversion unit 54 performs resolution conversion on an image signal of a color image input to the camera interface 51 by integrating signal values of a plurality of adjacent pixels to reduce the number of pixels.

  The tone-to-tone correction unit 55 performs tone correction and tone correction on the image signal of the color image output from the resolution conversion unit 54. As gradation correction, for example, gain adjustment is performed to brighten an image. As the color tone correction, for example, white balance correction is performed to suppress the influence of the color tone of the ambient light.

  The gamma correction unit 56 performs gamma correction on the image signal output from the gradation color tone correction unit 55 to correct the gradation of the image to the optimum characteristic according to the characteristic of the display device.

  The Y component generation unit 57 generates an image signal (luminance signal) of the Y component from the image signal output from the gamma correction unit 56. The UV component generation unit 58 generates image signals (color difference signals) of U component and V component from the image signal output from the gamma correction unit 56.

  The averaging reduction unit 59 makes the color image a predetermined size by averaging signal values of a predetermined number of pixels with respect to the image signals output from the Y component generation unit 57 and the UV component generation unit 58, respectively. Perform processing to reduce.

  Next, resolution conversion performed by the resolution conversion unit 54 will be described. FIG. 5 is an explanatory view showing the procedure of resolution conversion. FIG. 6 is an explanatory view showing a histogram before and after resolution conversion.

  In the imaging element of the color camera 11, as shown in FIG. 5A, pixels of each color of R, B and G are arranged in a Bayer pattern.

  In the resolution conversion unit 54, as shown in FIG. 5B, the signal values of a predetermined number of adjacent pixels are added to the pixels of the same color as a target, and the sum value is calculated as shown in FIG. As shown in, the signal value of one pixel.

  In the example shown in FIG. 5, the signal values of a total of 16 pixels of 4 × 4 are added. This increases the imaging sensitivity by 16 times. Also, the resolution is reduced to 1/16, and the amount of data is reduced to 1/16.

  In addition, although shown about R in FIG. 5, it is the same about B and G.

  By performing such resolution conversion, as shown in FIG. 6A, the signal value is biased to a dark range before resolution conversion, but as shown in FIG. After conversion, the signal value is spread over a wide range.

  As described above, in the present embodiment, resolution conversion is performed to reduce the number of pixels of a color image by adding signal values of a plurality of pixels. As a result, in a situation where there is a slight amount of ambient light due to streetlights and buildings, etc., the actual color information of the subject is included in the signal value of each pixel, so the subject values can be added by adding the signal values of a plurality of pixels. It is possible to output a color image in which the actual color of C appears clearly. In particular, in the case of a person, for example, the color of the clothes clearly appears, and in the case of a vehicle, the color of the vehicle body clearly appears, so that false recognition of the moving body can be avoided.

  By the way, since the color image generated by the camera device 1 is transmitted to the server device 2 via the network, it is desirable to reduce the data amount of the color image for the purpose of reducing the communication load.

  Here, it is conceivable to perform compression processing such as JPEG, but if compression processing is performed on a color image taken with no ambient light as in the night, ambient light is sufficient as in the daytime. The compression noise which did not occur in the color image photographed in the state of (1) appears remarkably, and the image quality is greatly reduced.

  On the other hand, in the present embodiment, by performing resolution conversion, the number of pixels of a color image is reduced, so the amount of data of the color image can be reduced. Further, compression processing may be further performed on a color image subjected to resolution conversion, and in this case, compression noise is significantly reduced as compared to the case where compression processing is performed without performing resolution conversion. be able to.

  Next, processing performed by the signal processing control unit 53 will be described. FIG. 7 is an explanatory view showing a processing mode set by the signal processing control unit 53. As shown in FIG. FIG. 8 is a flowchart showing the procedure of processing performed by the signal processing control unit 53.

  The signal processing control unit 53 compares the signal level acquired by the signal level detection unit 52 with a plurality of threshold values, and based on the comparison result, the degree of resolution conversion performed by the resolution conversion unit 54 is stepwise change.

  In the example shown in FIG. 7, three levels (minimum, middle, maximum) are set as the resolution conversion degree, divided into three processing modes based on the signal level. Thereby, appropriate resolution conversion can be performed so that the signal value of each pixel is not saturated.

  The first processing mode is implemented when the daytime is in a bright state. In this first processing mode, the level of resolution conversion is minimized, and the reduction ratio of resolution conversion is 1, ie, resolution conversion is not performed.

  The second processing mode is implemented when it is dimmed in the sunset or sunrise time zone. In this second processing mode, the level of resolution conversion is intermediate, and the reduction ratio of resolution conversion is 1/4. That is, by adding the signal values of a total of four pixels of 2 × 2, resolution conversion is performed to set the resolution to 1⁄4.

  The third processing mode is implemented when it is dark at night. In this third processing mode, the level of resolution conversion is maximum, and the reduction ratio of resolution conversion is 1/16. That is, by adding signal values of a total of 16 pixels of 4 × 4, resolution conversion is performed such that the resolution is 1/16.

  The signal processing control unit 53 performs averaging reduction unit 59 according to the degree of resolution conversion so that a color image of the same size is finally obtained regardless of the degree of resolution conversion performed by the resolution conversion unit 54. Set the degree of averaging reduction performed in.

  That is, when the reduction ratio of resolution conversion in the first processing mode is 1, the level of averaging reduction is maximum, and the reduction ratio of averaging reduction is set to 1/16. When the reduction ratio of resolution conversion in the second processing mode is 1/4, the level of averaging reduction is intermediate, and the reduction ratio of averaging reduction is 1/4. When the reduction ratio of resolution conversion in the third processing mode is 1/16, the level of averaging reduction is minimized, and the reduction ratio of averaging reduction is set to 1. That is, averaging reduction is not performed. As a result, a color image reduced to 1/16 is obtained in all processing modes.

  Specifically, as shown in FIG. 8, the signal level L obtained by the signal level detection unit 52 is compared with the two threshold values a and b (a <b), and the signal level L is the threshold value a. It is judged whether or not it is less than (ST101), and it is judged whether or not the signal level L is less than the threshold value b (ST102). Thus, the levels of resolution conversion and averaging reduction are determined in three processing modes.

  That is, when the signal level L is equal to or higher than the threshold value b (No in ST102), that is, in the daytime bright state, the first processing mode is set, and the resolution conversion level is set to minimum (ST103). ), The level of averaging reduction is set to the maximum (ST104).

  Also, when the signal level L is equal to or higher than the threshold a and lower than the threshold b (Yes in ST 102), that is, in the dull state in the sunset or sunrise time zone, the second processing mode is set. The resolution conversion level is set to the middle (ST105), and the averaging reduction level is set to the middle (ST106).

  When the signal level L is less than the threshold a (Yes in ST101), that is, when it is dark at night, the third processing mode is set, and the resolution conversion level is set to the maximum (ST107). ), The level of averaging reduction is set to the minimum (ST108).

  In the examples shown in FIGS. 7 and 8, three cases (first to third processing modes) are classified according to the signal level, but two cases or four or more cases are classified as cases. You may In addition, although the reduction ratio of resolution conversion is set to 1, 1/4, 1/16, resolution conversion is performed to set the resolution to 1/16 by adding signal values of a total of 64 pixels of 8 × 8. And so on, resolution conversion of various reduction rates is possible.

  Next, white balance correction performed by the gradation color tone correction unit 55 will be described. FIG. 9 is a flow chart showing the procedure of white balance correction.

  The gradation and tone correction unit 55 performs white balance correction on the image signal of the color image output from the resolution conversion unit 54. In white balance correction, the lightest (high luminance) area is regarded as white, and the color tone is corrected. For this reason, in an image in which a light, for example, a street lamp or a headlight of a vehicle is captured at night, the area of the light is the brightest, so this area is regarded as white and the color tone is corrected. At this time, if the light is not white, a color cast is generated in which the color of the image is entirely shifted.

  Therefore, in the present embodiment, the white balance correction is performed excluding the light area.

  Specifically, first, it is determined whether the signal level acquired by the signal level detection unit 52 is less than a predetermined threshold (ST201). This threshold is to identify nighttime and daytime.

  Here, if the signal level is less than the threshold (Yes in ST201), that is, if it is night, the area of the light in the color image is detected, and the pixels included in the area of the light are added up. It excludes from object (ST202).

  Next, the signal value of each pixel to be aggregated is summed up for each color of RGB, and the total value (RSUM, GSUM, BSUM) of each color is calculated (ST 203). Then, the gain of each color based on the total value of each color is multiplied by the input value (Rin, Gin, Bin) of each color to calculate the output value (Rout, Gout, Bout) of each color (ST 204). At this time, correction based on G is performed.

  On the other hand, when the signal level is equal to or higher than the threshold (No in ST201), that is, when it is daytime, the total value of each color is calculated with all pixels in the color image as aggregation targets (ST203). The output value of each color is calculated (ST 204).

  Next, gradation correction performed by the gradation color tone correction unit 55 will be described. FIG. 10 is an explanatory view showing a state of gradation correction performed by the gradation color tone correction unit 55. As shown in FIG.

  The tone-to-tone correction unit 55 adds a gain to the image signal of the color image output from the resolution conversion unit 54 to perform tone correction (gain adjustment) to brighten the color image.

  The example shown in FIG. 10 is a nighttime color image in which the light of a street lamp is taken. As shown in FIG. 10A, the original image is dark as a whole and it is difficult to see the subject.

  Here, if a large gain is uniformly applied to the image signal of the original image, as shown in FIG. 10B, the entire image becomes bright and the subject can be easily seen in an area away from the light, but halation As it becomes noticeable, it is difficult to see the subject in the area near the light.

  On the other hand, if a small gain is uniformly applied to the image signal of the original image, halation is reduced as shown in FIG. 10C, but the entire image is only slightly brightened, and it is difficult to see the subject. Not much improvement.

  Therefore, in the present embodiment, tone correction optimized according to the area is performed. That is, a dark area away from the light gives a large gain, and a bright area near the light gives a small gain.

  As a result, as shown in FIG. 10D, the subject is easy to see in the area away from the light, and halation is reduced, so the subject is easy to see in the area near the light. As described above, by providing different gains depending on the area, it is possible to obtain an optimal image that is not affected by halation.

  As described above, the embodiment has been described as an example of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can be applied to embodiments in which changes, replacements, additions, omissions, and the like have been made. Moreover, it is also possible to combine each component demonstrated by said embodiment, and to set it as a new embodiment.

  For example, in the above embodiment, an example in which a moving object to be monitored is mainly a person is described. However, the moving object to be monitored is not limited to a person, and may be an animal or a vehicle.

  In the above embodiment, the control is performed based on the signal level representing the brightness of the ambient light, but the brightness of the ambient light changes regularly due to the change of the sunshine time according to the season or time It is also possible to control based on time information. However, since the brightness of the ambient light changes according to the weather, the control based on the signal level can perform the control with higher accuracy.

  In the above embodiment, various image processing (signal processing) such as resolution conversion is performed by the camera device. However, all or part of the image processing may be performed by the server device. However, since the resolution conversion and the averaging reduction processing reduce the communication load by reducing the data amount of the image, it is desirable to perform this processing with the camera device.

  Furthermore, in the above embodiment, the processed color image and monochrome image are output from the camera device, but an image composition that combines the color image captured at night and the monochrome image to generate a composite image May be performed. Note that this image combination may be performed by either the camera apparatus or the server apparatus.

  In image composition, for example, processing of acquiring color information from a color image and coloring the monochrome image using the color information is performed. In this embodiment, a color image in which the actual color of the subject clearly appears is obtained by resolution conversion, and color information of a moving object appearing at night can be accurately obtained from this color image. In addition, a high-definition monochrome image is obtained by photographing with near-infrared light, and the color of a moving object is faithfully reproduced by coloring the monochrome image using color information acquired from the color image. Night color images can be generated.

  The moving object monitoring apparatus and the moving object monitoring system according to the present invention have an effect of being able to output an appropriate color image in which the actual color of the subject clearly appears according to the situation of ambient light with a low cost configuration. As a moving object monitoring system that outputs an image obtained by capturing an image of a monitoring area in which a moving object to be monitored appears and a moving image from the moving object monitoring device to an image storage device via a network. It is useful.

1 Camera device (moving object monitoring device)
2 Server device (image storage device)
11 color camera 12 monochrome camera 14 communication unit 15 control unit 21 signal processing unit 52 signal level detection unit 53 signal processing control unit 54 resolution conversion unit 59 averaging reduction unit

Claims (7)

A moving object monitoring apparatus that composites and outputs a color image and a monochrome image obtained by capturing a monitoring area in which a moving object to be monitored appears.
A color camera for photographing the monitoring area with ambient light;
A monochrome camera that captures the monitoring area with infrared light;
A signal processing unit that processes the color image output from the color camera and the monochrome image output from the monochrome camera;
An image combining unit for acquiring color information from the color image and performing processing for coloring the monochrome image using the color information;
Equipped with
The signal processing unit
A resolution conversion unit that reduces the number of pixels of the color image by adding signal values of a plurality of pixels adjacent to each other in the color image;
A signal processing control unit that controls the operation of the resolution conversion unit based on the shooting environment of the monitoring area;
A moving body monitoring device characterized by having. A signal level detection unit that detects the signal level of the color image;
The moving object monitoring apparatus according to claim 1, wherein the signal level is referred to in order to determine the photographing environment.   The moving object monitoring apparatus according to claim 2, wherein the signal processing control unit suspends the operation of the resolution conversion unit when it is determined that the signal level is equal to or higher than a predetermined threshold value.   The signal processing control unit compares the signal level with a plurality of threshold values, and changes the degree of resolution conversion in the resolution conversion unit stepwise based on the comparison result. The moving body monitoring device according to claim 2 or 3. The image processing apparatus further includes an averaging reduction unit that performs reduction processing by averaging on the signal of the color image output from the resolution conversion unit,
The signal processing control unit sets the degree of averaging reduction in the averaging reduction unit so as to obtain the color image of the same size according to the degree of resolution conversion in the resolution conversion unit. The moving body monitoring device according to any one of claims 1 to 4, which is characterized by the following. A moving object monitoring system for transmitting a color image and a monochrome image obtained by capturing a monitoring area in which a moving object to be monitored appears in a moving object monitoring device from the moving object monitoring device to a server device via a network.
The moving body monitoring device
A color camera for photographing the monitoring area with ambient light;
A monochrome camera that captures the monitoring area with infrared light;
A signal processing unit that processes the color image output from the color camera and the monochrome image output from the monochrome camera;
And a communication unit for transmitting the color image processed by the signal processing unit and the monochrome image to the server device.
The server device is
The image combining unit is configured to obtain color information from the signal of the color image and use the color information to color the signal of the monochrome image.
Furthermore, the signal processing unit
A resolution conversion unit that reduces the number of pixels of the color image by adding signal values of a plurality of pixels adjacent to each other in the color image;
A signal processing control unit that controls an operation of the resolution conversion unit based on a shooting environment of the monitoring area;
The moving body monitoring system characterized by having.   7. The apparatus according to claim 6, wherein the communication unit adds shooting information including at least one of an installation location, a camera attribute, shooting time, and shooting conditions to the color image and the monochrome image and transmits the information. Motion monitoring system.

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