JP2015088819A - Imaging simulation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To grasp how precisely imaging is being performed by a camera.SOLUTION: An imaging simulation device is configured to calculate an amount of monitoring representing a monitoring degree at a predetermined position within a monitoring space by means of an imaging apparatus installed in the monitoring space. The imaging simulation device stores a three-dimensional space model of the monitoring space and imaging condition information including an installation position, an attitude, an angle of view and a resolution of the imaging apparatus. An evaluation region is set on the space model and while using the imaging condition information, the number of pixels in a region corresponding to the evaluation region on a projection surface where the space model is projected in a three-dimensional manner, is calculated. From a ratio of the pixels per unit area of the evaluation region, the amount of monitoring at the predetermined position is calculated and outputted.

Description

  The present invention relates to an imaging simulation apparatus that evaluates by simulation how much a predetermined position in a monitoring space is monitored by an imaging apparatus installed in the monitoring space.

  In recent years, for the purpose of security, cases in which a large number of imaging devices such as a visible camera and an infrared camera are installed and monitored in a wide monitoring space such as a town or a building are increasing. When many imaging devices are installed in such a large monitoring space, it is necessary for management that the administrator can easily grasp which region in the monitoring space can be imaged by each imaging device at the planning stage. Has been.

  For example, in Patent Literature 1, an imaging range of an imaging device is generated and explicitly shown on a map (plan view) of a monitoring space using information such as the installation position, orientation (optical axis), and focal length of the imaging device. Techniques to do this are disclosed.

JP2008-011433A

  However, in the above-described conventional technology, even if it is possible to grasp whether or not the predetermined area in the monitoring space is within the imaging range of the imaging device, how much the area is captured by the imaging device. The administrator could not grasp whether there was. For example, when an area is imaged using the same imaging device, the amount of information (pixels) of the area of the captured image corresponding to the area when the image is captured widely from a distant position and when the image is captured from a nearby position. The number of the latter captured image is larger, and the latter captured image can grasp the region in detail. In addition, when imaging a region from the same position using different imaging devices, an imaging device having a higher resolution can grasp the region in more detail. Therefore, there is a monitoring need not only to determine whether or not a certain position in the monitoring space is included in the imaging range, but also to know how much the image is captured.

  Therefore, the present invention has an object to satisfy the above monitoring needs by obtaining a monitoring amount representing a degree of monitoring such as how much a predetermined position in the monitoring space is imaged by the imaging device.

In order to achieve the above-described object, an imaging simulation apparatus for obtaining a monitoring amount representing a monitoring degree at a predetermined position in the monitoring space by one or a plurality of imaging apparatuses installed in the monitoring space,
Imaging including a space model expressing the monitoring space as a three-dimensional virtual space, information relating the installation position and orientation of the imaging device in the monitoring space to the virtual space, and the angle of view and resolution of the imaging device A storage unit for storing condition information and an evaluation area including a position on the space model corresponding to the predetermined position are set, and the space model is three-dimensionally projected from the image pickup apparatus using the image pickup condition information The number of pixels in the area corresponding to the evaluation area on the projection surface is obtained, and the monitoring amount at the predetermined position is determined from the ratio of pixels per unit area of the evaluation area using the number of pixels and the area corresponding to the evaluation area. There is provided an imaging simulation apparatus characterized by having a control unit for obtaining the output and an output unit for outputting the monitoring amount.

  With this configuration, the administrator can easily grasp the degree of monitoring such as how much a predetermined position in the monitoring space is imaged based on the monitoring amount output from the output unit. Therefore, the administrator determines the monitoring status at the position in consideration of the monitoring amount, and if necessary, installs or changes the imaging device, arranges security guards, or points the monitoring robot. , Making it easier to deal with.

  As a preferred aspect of the present invention, the storage unit further stores a frame rate of the imaging apparatus, and the control unit calculates the monitoring amount so as to increase as the frame rate increases.

  In general, as the frame rate increases, an object that moves quickly can be captured, or the characteristics of many objects can be captured in a short time, and thus the amount of information that can be acquired from a captured image increases. Therefore, with the above configuration, the administrator can grasp the monitoring amount with higher accuracy in consideration of the frame rate, and thus can take a more appropriate response in monitoring.

  As a preferred aspect of the present invention, the storage unit further stores a depth of field of the imaging device, and the control unit is a distance from the installation position of the imaging device to the center of gravity position of the evaluation area. And the amount of monitoring is calculated to be smaller as the distance deviates from the range of the depth of field.

  In general, the more an object is located outside the depth of field, the more blurred the object will be out of focus, so even if it is within the imaging range of the imaging device The amount of information obtained from the image is relatively small. Therefore, with the above configuration, as the depth of field, for example, the near point distance (front end distance) and the far point distance (rear end distance) are stored in advance in the storage unit, and the distance to the center of gravity position of the evaluation region is The monitoring amount is calculated to be smaller as the distance from the depth of field is out of the distance range (that is, the smaller the distance from the near point / the larger the distance from the far point). As a result, the administrator can grasp the monitoring amount with higher accuracy in consideration of the depth of field, and can take a more appropriate response when monitoring.

  Moreover, as a preferable aspect of the present invention, the control unit further generates a monitoring amount image in which a region of the space model corresponding to the evaluation region is represented by a color or shading corresponding to the monitoring amount, and the output The unit displays and outputs the monitoring amount image.

  With this configuration, it is possible to calculate a monitoring amount for a plurality of evaluation regions in the monitoring space and output a monitoring amount image represented by colors and shades corresponding to the monitoring amount for the evaluation region. As a result, the administrator refers to the monitoring amount image so that “roughness” of monitoring such as a portion that is firmly monitored (imaging) by the imaging device and a portion that is not monitored (imaging) in a wide monitoring space. , Can be grasped at a glance.

  As a preferred aspect of the present invention, the storage unit further stores in advance a threshold value of the monitoring amount at a predetermined height, and the control unit further stores the monitoring amount of the evaluation area at the height. Calculating and generating an identification area image in which the evaluation area whose monitoring amount is larger than the threshold value is displayed so as to be distinguishable from other spatial model areas, and the output unit displays and outputs the identification area image And

  With this configuration, the administrator can grasp at a glance an area larger than a predetermined monitoring amount at a predetermined height. Thereby, for example, it is possible to identify an area that can be authenticated by an authentication device that authenticates an object such as a person or a car using an imaging device installed in a monitoring space. That is, the height of the object part to be authenticated by the authentication device from the ground (for example, the height of the face or the height of the license plate) and the threshold value indicating the lower limit of the monitoring amount that can be authenticated by the authentication device. By storing an area where the monitoring amount at the height is equal to or greater than the threshold value as an identification area image, the administrator who has viewed the identification area image can easily identify an area that can be authenticated by the authentication device in a wide monitoring space. Can be grasped.

The program of the present invention is a program for obtaining a monitoring amount representing a monitoring degree at a predetermined position in the monitoring space by one or a plurality of imaging devices installed in the monitoring space,
Imaging including a space model expressing the monitoring space as a three-dimensional virtual space, information relating the installation position and orientation of the imaging device in the monitoring space to the virtual space, and the angle of view and resolution of the imaging device Condition information, and the program stores a processing for setting an evaluation area including a position on the spatial model corresponding to the predetermined position in the computer, and the imaging apparatus using the imaging condition information. Pixels per unit area of the evaluation region using the processing for obtaining the number of pixels in the region corresponding to the evaluation region on the projection plane on which the spatial model is three-dimensionally projected, and the area corresponding to the evaluation region And a process of obtaining the monitoring amount at the predetermined position from the ratio of.

  Also with this program, as described above, the administrator can easily grasp the degree of monitoring such as how much the predetermined position of the monitoring space is imaged.

  As described above, according to the present invention, the administrator can grasp the monitoring amount indicating the degree of monitoring such as how much the predetermined position in the monitoring space is imaged by the imaging device.

Block diagram showing the configuration of the imaging simulation device Diagram explaining the spatial model Table showing evaluation area information A diagram showing the spatial model divided into evaluation areas The figure explaining pixel number calculation processing The figure explaining pixel number calculation processing Flow chart showing processing in the control unit A figure showing an example of a monitoring amount image The figure explaining pixel number calculation processing The figure showing the other example of a monitoring amount image The figure showing an example of an identification area image

  Hereinafter, when a predetermined area outside (town) is set as a monitoring space and a plurality of imaging devices are installed in the monitoring space, how much the predetermined position in the monitoring space is captured by these imaging devices. In order to be able to grasp at a glance about the degree of monitoring, such as whether or not it is being performed, a monitoring amount representing the degree of monitoring is calculated for each region of the monitoring space, and the region is colored by a color (or shading) based on the calculated monitoring amount An embodiment of an imaging simulation apparatus that performs display output will be described in detail with reference to the accompanying drawings. Note that the image pickup apparatus in the present embodiment is a so-called monitoring camera including an image pickup element such as a CCD element or a C-MOS element, an optical system part, etc., and is installed on the upper surface of a building wall or on a utility pole for monitoring. Although the image is taken from a bird's-eye view, the details are not essential to the present invention, and the description thereof will be omitted.

(About the overall configuration of the imaging simulation device)
As shown in FIG. 1, the imaging simulation apparatus 1 of the present embodiment is schematically configured to include a storage unit 11, a control unit 12, a display unit 13, and an input unit 14. The input unit 14 is an information input device such as a keyboard, a mouse, a touch panel, or a portable storage medium reading device. An administrator of the imaging simulation apparatus 1 can use the input unit 14 to store, for example, three-dimensional shape data of a space model 111 described later in the storage unit 11 or set various setting information.

  The storage unit 11 is an information storage device such as a ROM, RAM, or HDD. The storage unit 11 stores various programs and various data, and inputs / outputs such information to / from the control unit 12. The various data includes the space model 111, the imaging condition information 112, the frame rate 113, the evaluation area information 114, and other various information used for the processing of the control unit 12 (for example, the number of pixels in the evaluation area described later, the monitoring amount, etc. ) Is remembered.

  The space model 111 is coordinate information representing a three-dimensional virtual space including three-dimensional shape data created by modeling an object such as a real world building, ground, or tree existing in the monitoring space. The three-dimensional shape data in the space model 111 may be created by three-dimensional CAD based on the monitoring space shape information, or using data obtained by capturing the three-dimensional shape of the monitoring space with a three-dimensional laser scanner or the like. Also good. The space model 111 created in this way is stored in the storage unit 11 by being set and registered from the input unit 14 by the administrator. FIG. 2 represents the space model 111 used in the present embodiment as a three-dimensional shape from coordinate information representing a three-dimensional virtual space.

  The imaging condition information 112 includes information on the installation position and orientation of the imaging device installed in the monitoring space, information on the angle of view (viewing angle), and information on the resolution (number of vertical and horizontal pixels). Remembered. Here, information regarding the installation position and orientation is stored as a value associated with coordinate information in the virtual space of the space model 111. That is, the information regarding the installation position represents the monitoring space (real space) as a three-dimensional orthogonal coordinate system, and the relative value from the reference point to the coordinate value of the reference point whose coordinates are known in the three-dimensional orthogonal coordinate system, This is information expressed as coordinate data calculated using a known technique such as measuring and correcting the direction. The information related to the posture is information related to the rotation angle of the optical axis of the imaging apparatus with respect to the coordinate axis of the three-dimensional orthogonal coordinate system, and can be obtained from so-called pan angle and tilt angle of the imaging apparatus. The imaging condition information 112 is stored in the storage unit 11 by being registered by the administrator from the input unit 14 at the time of initial setting.

  The frame rate 113 is information indicating the number of captured images (number of frames) acquired per unit time of the imaging device installed in the monitoring space, and the number of frames per second for each imaging device is, for example, 30 fps. Is memorized. The frame rate 113 is stored in the storage unit 11 by being registered from the input unit 14 by the administrator at the time of initial setting.

  The evaluation area information 114 is information about an evaluation area that is a unit area for calculating a monitoring amount set on the space model 111, and as shown in FIG. 3, the identification information of each evaluation area and the range of the evaluation area Is stored as a table that associates the coordinate information representing the area with the area in the real space corresponding to the evaluation area. In the present embodiment, like the areas divided by dotted lines in FIG. 4, all areas of the space model 111 corresponding to the ground and the building wall surface in the monitoring space are divided as evaluation areas, and the monitoring amount of each evaluation area Is calculated. Therefore, as shown in FIG. 3, a plurality of pieces of information (records) are stored in the evaluation area information 114 for the number of evaluation areas. The evaluation area information 114 is automatically calculated and set by an evaluation area setting unit 121 described later. However, the present invention is not limited to this. When a predetermined position is designated in the space model 111 by the administrator using the input unit 14 (for example, a mouse or the like), an area within a predetermined range including the position (for example, 1 m × in real space) An area in a range corresponding to 1 m) may be used as an evaluation area, and information including a record for the one evaluation area may be stored as the evaluation area information 114.

  The control unit 12 is configured by a computer including a CPU and the like, and performs an evaluation area setting unit 121, a pixel number calculation unit 122, a monitoring amount calculation unit 123, a monitoring amount image, in order to execute a series of processes shown in FIG. Generation means 124 is included.

  The evaluation area setting unit 121 sets an evaluation area, which is a unit area for calculating the monitoring amount, on the space model 111 and performs an evaluation area setting process for storing the evaluation area information 114 in the storage unit 11. In the present embodiment, like the areas divided by dotted lines in FIG. 4, all areas of the space model 111 corresponding to the ground of the monitoring space and the building wall surface are divided as evaluation areas, and the evaluation for each evaluation area is performed. The area information 114 is obtained. That is, all the regions of the space model 111 corresponding to the ground of the monitoring space and the building wall surface are divided so as to be within a preset area, and each of the divided regions is used as an evaluation region, and coordinate values representing ranges Then, the geometrical calculation of the area in the real space corresponding to the evaluation area is performed. However, it is not limited to the area in the real space, but may be a virtual area corresponding to the area of the space model 111.

  The pixel number calculation unit 122 performs pixel number calculation processing for calculating the number of pixels in an area corresponding to an evaluation area on a projection plane obtained by three-dimensionally projecting (perspective projection) the spatial model 111 from the imaging apparatus using the imaging condition information 112. Do. Details of the pixel number calculation process will be described below.

  In the pixel count calculation process, first, a virtual camera is arranged on the space model 111 based on the installation position and orientation of the imaging condition information 112. Here, the virtual camera is a virtual camera that imitates an imaging device arranged in a monitoring space that is a real space in a space model 111 that is a virtual space, and the installation position, orientation, and image of the imaging device. The virtual space is imaged by the corner, resolution, etc., and a virtual camera image is output. FIG. 5 is a diagram schematically illustrating the pixel number calculation process. In FIG. 5, reference numerals 111 a and 111 b are notched portions of the space model 111, of which 111 a is equivalent to the ground of the monitoring space, and 111 b is a building that exists in the monitoring space. It shall correspond to a wall surface. As shown in FIG. 5, in the pixel count calculation process, the optical center O of the virtual camera 32 is set in the virtual space based on the installation position of the imaging condition information 112, and the optical axis (rotation with respect to the coordinate axis) of the virtual camera 32 is set. (Angles ω, φ, κ) are set based on the posture of the imaging condition information 112.

Next, in the pixel number calculation process, a virtual camera image corresponding to an image captured from the virtual camera 32 is obtained from the position and orientation of the virtual camera 32 based on the angle of view resolution of the imaging condition information 112. At this time, a virtual camera image is obtained by rendering processing using a known computer graphics technique. The method is described in detail in, for example, “Computer Graphics” (Computer Graphics Editorial Board Editing / Publishing, 2006). In FIG. 5, the optical center O of the virtual camera 32 is the top vertex. The quadrangular pyramid Oa′b′c′d ′, which corresponds to the field of view of the virtual camera 32 geometrically calculated from the imaging condition information 112, is a projection plane that is in contact with the quadrangular pyramid and is perpendicular to the optical axis. abcd corresponds to a virtual camera image. The interference plane ABECDF between the quadrangular pyramid and the space model 111 corresponds to the imaging range of the virtual camera 32, and a projection of the space model 111 in the imaging range as a two-dimensional image is displayed as a virtual camera image. That is, in FIG. 5, the part indicated by the symbol I on the space model 111a is projected to the part indicated by the symbol i of the virtual camera image (projection plane).

  Next, in the pixel count calculation process, an image area of a virtual camera image (projection plane) corresponding to a predetermined evaluation area on the space model 111 is obtained. For example, as shown in FIG. 5, when an evaluation area 30 for which a monitoring amount is desired to be calculated is an area composed of a rectangular GHIJ shown on the space model 111a, a virtual camera image (projection plane) corresponding to the evaluation area 30 An image region ghij (hereinafter referred to as “corresponding region 31”) is obtained. Next, in the pixel number calculation process, the number of pixels in the corresponding region 31 on the virtual camera image is counted. In this way, in the pixel number calculation process, the number of pixels in the corresponding area 31 corresponding to the evaluation area on the projection plane on which the spatial model 111 is three-dimensionally projected is obtained using the imaging condition information 112.

  In the present embodiment, the number of pixels of the corresponding area 31 corresponding to the evaluation area is obtained using the virtual camera image obtained by the rendering process. However, the present invention is not limited thereto, and it is not necessary to output the virtual camera image. The number of pixels can be obtained by known geometric calculation. That is, the field of view of the space model 111 defined in the three-dimensional virtual space is converted by the conversion matrix obtained from the installation position / orientation of the imaging apparatus, and further, the perspective transformation is performed by the conversion matrix obtained from the angle of view of the imaging apparatus. Thus, it is projected onto a two-dimensional projection plane. Then, by applying a known hidden surface removal technique (using object space algorithm, image space algorithm, priority algorithm, etc.), the surface hidden by the surface existing in front is erased, so that the projected surface of any evaluation area For the corresponding region 31 projected above, the area ratio of the corresponding region 31 to the area of the entire projection surface can be calculated. Using the area ratio and the resolution, the number of pixels in the corresponding region can be calculated. The above-described geometric calculation is described in detail in the aforementioned “computer graphics”.

  The monitoring amount calculation means 124 uses the number of pixels in the evaluation area calculated by the pixel number calculation means 122 and the area in the real space corresponding to the evaluation area calculated in the evaluation area setting process. A ratio of pixels per unit area (hereinafter referred to as “pixel density”) is calculated, and a monitoring amount calculation process for obtaining a monitoring amount of the evaluation region using the pixel density is performed. Details of the monitoring amount calculation process will be described below.

  In the monitoring amount calculation process, first, the pixel density of the evaluation region to be evaluated is calculated using the pixel number N of the evaluation region calculated by the pixel number calculation unit 122 and the area S of the evaluation region information 114. ρ [pics / m ^ 2] = N / S. Next, using the calculated pixel density ρ and the frame rate 113, the larger the frame rate 113, the larger the monitoring amount. In the present embodiment, the monitoring amount is calculated by multiplying the normalized value by the pixel density ρ according to the reference frame rate. That is, when the frame rate used as a reference is 30 fps and the frame rate of the imaging apparatus for which the pixel density ρ is obtained is 60 fps, the monitoring amount V = pixel density ρ × (60/30). Note that, depending on the evaluation region, the image may be captured by a plurality of imaging devices. The monitoring amount of the evaluation area captured by such a plurality of imaging devices is calculated by the sum of the monitoring amounts calculated for each imaging device.

  The monitoring amount for a predetermined evaluation region can be calculated by a series of processing such as the above-described evaluation region setting processing, pixel number calculation processing, and monitoring amount calculation processing. Here, the monitoring amount when the evaluation area is behind a building or the like will be described. FIG. 6 shows the space model 111 when the collar 111c protrudes from the wall surface 111b. As shown in the figure, since the part of the evaluation area 30a is hidden behind the collar 111c when viewed from the virtual camera 32, the corresponding area 31a becomes small. Therefore, since the number of pixels in the corresponding area 31a is counted to be small, the monitoring amount of the corresponding area 31a is smaller than the monitoring amount of the evaluation area 30 in FIG. In addition, for the evaluation area 30b that is entirely hidden behind the buttock 111c when viewed from the virtual camera 32, there is no corresponding area and the monitoring amount is zero. As described above, the present invention obtains the monitoring amount based on the three-dimensional structure of the monitoring space so that the monitoring amount in the evaluation area which is out of the imaging range behind the building or the like is calculated to be small. Can do. Therefore, the manager can take a more appropriate response (for example, arranging a guard in a blind spot area) based on the three-dimensional structure of the monitoring space.

  The monitoring amount image generation unit 124 uses a space model 111 in the storage unit 11, the evaluation region information 114 set by the evaluation region setting unit 121, and the monitoring amount calculated by the monitoring amount calculation unit 123. A monitoring amount for generating a monitoring amount image that is a virtual image obtained by rendering the space model 111 from the viewpoint / view and is colored with a color (or light and shade) corresponding to the monitoring amount corresponding to the evaluation region in the space model 111 Image generation processing is performed, and processing for outputting the generated monitoring amount image to the display unit 24 is performed. Details of the monitoring amount image generation processing will be described below.

  In the monitoring amount image generation process, first, information on the viewpoint and visual field required in the rendering process performed to generate the monitoring amount image is read from the storage unit 11. It is assumed that the information regarding the viewpoint and the visual field is fixedly set and input by an administrator or the like at the time of initial setting. However, an administrator or the like may perform setting input using the input unit 14 as necessary. Next, in the monitoring amount image generation process, a virtual image obtained by capturing the space model 111 is generated using information on the viewpoint and visual field read from the storage unit 11. Then, based on the information about the range of the evaluation area in the evaluation area information 114, the image area corresponding to the evaluation area in the generated virtual image is colored (texture mapping) with a color corresponding to the monitoring amount corresponding to the evaluation area. . For example, the larger the monitoring amount, the darker the red color, and the smaller the monitoring amount, the closer it becomes white (colorless).

  The display unit 13 is an information display device such as a display. The display unit 13 displays the monitoring amount image output from the monitoring amount image generation unit 124 of the control unit 12. The display unit 13 functions as an output unit in the present invention.

(About processing executed by the control unit 12 of the imaging simulation apparatus 1)
Hereinafter, an example of the flow of processing executed by the control unit 12 of the imaging simulation apparatus 1 according to the present embodiment will be described in detail with reference to FIG. In the present embodiment, description will be made assuming that two imaging devices are installed in the monitoring space.

  Prior to the operation of the imaging simulation apparatus 1, the administrator performs various initial settings such as setting of the imaging condition information 112 and registration of the spatial model 111 using the input unit 14 of the imaging simulation apparatus 1 (ST1). In the present embodiment, since it is assumed that two imaging devices are installed in the monitoring space, the imaging condition information 112 is registered for each imaging device with initial settings. Further, the following processing will be described assuming that the three-dimensional shape data of FIG.

  Next, the evaluation area setting unit 121 performs an evaluation area setting process for setting an evaluation area, which is a unit area for calculating a monitoring amount, on the space model 111, such as an area represented by a dotted line in FIG. 4 (ST2). In the evaluation area setting process, a coordinate value representing the range of the evaluation area and an area in the real space corresponding to the evaluation area are obtained and stored as evaluation area information 114 in the storage unit 11. In the subsequent processing of loop 1 in FIG. 7, processing is performed for each set evaluation area. That is, the loop 1 means that the number of evaluation areas set is executed. In the following description, the target evaluation area refers to an evaluation area that is a processing target in the loop 1. Further, in the processing of the loop 2 in FIG. 7, the processing is performed for each imaging device installed in the monitoring space. In other words, the loop 2 means that the number of executions is equal to the number of installed imaging devices. In the following description, the target imaging device refers to an imaging device that is a processing target in loop 2.

  Next, the pixel number calculation means 122 performs a pixel number calculation process (ST3). In the pixel count calculation process, the imaging condition information 112 corresponding to the target imaging device is read, and the projection plane (two-dimensional virtual projection) obtained by three-dimensionally projecting (perspective projection) the spatial model 111 from the imaging device using the imaging condition information 112. In the camera image), the number of pixels in the image area (corresponding area) corresponding to the target evaluation area is calculated. Since the details of the pixel number calculation process have been described above, the description thereof is omitted here.

  Next, the monitoring amount calculation unit 123 uses the number of pixels calculated in ST3, the area in the real space corresponding to the target evaluation area calculated in ST2, and the frame rate 113 of the target imaging device to perform target imaging. A monitoring amount calculation process for calculating the monitoring amount of the target evaluation area by the apparatus is performed (ST4). Since the details of the monitoring amount calculation processing have been described above, description thereof is omitted here.

  Next, the monitoring amount calculation means 123 calculates the sum of the monitoring amounts of the target evaluation area calculated for each target imaging device in the loop 2, and calculates the value as the monitoring amount of the target evaluation area (ST5). In general, when a predetermined evaluation area is imaged by a plurality of imaging devices, the amount of information (= degree of monitoring) obtained for the evaluation area is larger than when one apparatus is used. Therefore, by calculating the monitoring amount of the target evaluation area as the sum of the monitoring amounts by the respective imaging devices, it is possible to easily calculate the monitoring amount for the monitoring space where a plurality of imaging devices are installed. The monitoring amount calculated in this manner is temporarily stored in the storage unit 11 in association with the identification information of each target evaluation region, and the process is repeated so as to calculate the monitoring amount for all the evaluation regions in the loop 1.

  Next, the evaluation area setting unit 121 uses the monitoring amount of all evaluation areas calculated in loop 1, the evaluation area information 114 set in ST2, and the space model 111 of the storage unit 11 to monitor the amount of monitoring. Monitoring amount image generation processing for generating an image is performed (ST6). Since the details of the monitoring amount image generation processing have been described above, the description thereof is omitted here. Next, the control unit 12 performs output processing for displaying and outputting the monitoring amount image generated in ST6 on the display unit 13 (ST7).

  FIG. 8 is a diagram illustrating an example of the monitoring amount image 40. In FIG. 8, reference numerals 32 a and 32 b represent virtual cameras corresponding to two imaging devices installed in the monitoring space. In the present embodiment, the imaging device corresponding to the virtual camera 32a images a street between buildings from a relatively low position, and the imaging device corresponding to the virtual camera 32b images a wide range from a relatively high altitude position. doing. As shown in the figure, the monitoring amount of the evaluation area within the dotted lines indicated by reference numerals 33a and 33b, which are positions in the vicinity of the visual field direction of the virtual cameras 32a and 32b, is displayed in a dark color, and it can be easily understood that the monitoring amount is large. . In particular, it can be seen that the region 33a in the vicinity of the visual field direction of the virtual camera 32a picked up from a low position has a larger monitoring amount than the region 33b, and this region 33a has a larger amount of information (pixels). Number). On the other hand, it can be seen that the monitoring amount is small in the region 33b in the vicinity of the visual field direction of the virtual camera 32b that captures a wide range from the high altitude position compared to the region 33a. This means that the area 33a is away from the virtual virtual camera 32b, so that the image is captured with a smaller amount of information (number of pixels) than the area 33a. In addition, it can be understood from FIG. 6 that the monitoring amount of the region 33c where the visual field of the virtual camera 32a and the visual field of the virtual camera 32b overlap is relatively large. This is because the monitoring amount by the virtual camera 32a and the virtual camera 32b in ST5. This is because the sum total with the amount of monitoring by.

  As described above, the imaging simulation apparatus 1 according to the present embodiment monitors the monitoring amount indicating the degree of monitoring such as how much a predetermined position in the monitoring space is imaged by the imaging apparatus installed in the monitoring space. It can be aggregated and displayed as a quantity image. Thereby, the administrator can grasp at a glance the degree of monitoring, such as how much the image is captured by these imaging devices, by referring to the monitoring amount image output from the display unit 13. . Therefore, the administrator grasps a region that is weakly monitored by the existing imaging device, for example, a region that is displayed small (with a small number of pixels) in the monitoring image even if included in the imaging range of the imaging device. can do. Then, in order to ensure the security of the area where the monitoring is weak, it is possible to take measures such as adding an imaging device, arranging guards, or pointing the monitoring mobile robot.

  By the way, the present invention is not limited to the above-described embodiment, and may be implemented in various different embodiments within the scope of the technical idea described in the claims. Further, the effects described in the embodiments are not limited to this.

  In the above embodiment, in calculating the monitoring amount, the imaging condition information 112 such as the installation position and orientation of the imaging apparatus, the angle of view, and the resolution is used. However, the present invention is not limited to this, and the monitoring amount may be calculated by further using the depth of field of the imaging device. In general, the more an object is located outside the depth of field, the more blurred the display will be because the object is out of focus (focus). Even if the image is captured, the amount of information obtained from the captured image is relatively small in such a case. Therefore, a more accurate monitoring amount can be calculated by considering the depth of field. For example, a near point distance (front end distance) and a far point distance (rear end distance) are stored in advance in the storage unit 11 as the depth of field. Then, the evaluation area setting unit 121 geometrically calculates the distance from the optical center O (installation position of the imaging device) of the virtual camera to the gravity center position of the evaluation area. Then, the monitoring amount calculation unit 123 is configured such that the monitoring amount becomes smaller as the distance is smaller than the near point distance, and the monitoring amount is smaller as the distance is larger than the far point distance. Correct it to a value. Thereby, the administrator can grasp a more appropriate monitoring amount in consideration of the depth of field. The depth of field is not stored in the storage unit 11 in advance, but other parameters (for example, focal length, aperture value, etc.) are stored in the storage unit 11 in advance, and a known method using the parameters is stored. The depth of field may be calculated by

  In the above embodiment, the evaluation area setting unit 121 sets the area of the space model 111 corresponding to the ground and the building wall surface of the monitoring space as the evaluation area. May be set as the evaluation region. For example, as shown in FIG. 9, the evaluation area setting unit 121 sets an evaluation area 30c such as a sphere in the sky, and the pixel number calculation unit 122 calculates the number of pixels in the corresponding area 31c corresponding to the evaluation area 30c. Thus, the monitoring amount image generation unit 124 can similarly calculate the monitoring amount in the evaluation area 30c. FIG. 10 shows an example of a monitoring amount image 40 when an evaluation region is set above the ground where a person can pass in the monitoring space, and the monitoring amounts at a plurality of locations in the sky are calculated. Thus, by calculating not only the monitoring amount of the area in contact with the space model 111 such as the ground surface or the wall surface, but also the monitoring amount of the sky portion, the administrator can accurately grasp the monitoring amount at a predetermined height. it can. Therefore, for example, the present invention can be used when it is desired to grasp the monitoring amount at the height of the person's face position.

In the above-described embodiment, the monitoring amount image generation unit 124 generates a monitoring amount image colored in colors or shades according to the monitoring amount, and displays and outputs it on the display unit 13. The monitoring amount may be output as a numerical value without generating the amount image. For example, when the administrator designates a predetermined point in the monitoring space using the input unit 14 (for example, a mouse), the monitoring amount of the evaluation area including the point is calculated, and the monitoring amount is displayed as a numerical value on the display unit 13. It may be output.
Alternatively, the monitoring amount may be calculated for every region in the monitoring space, and the region having the monitoring amount equal to or smaller than a predetermined threshold may be output as an image so that it can be distinguished from other regions.
Alternatively, an area that can be authenticated by the authentication apparatus may be displayed and output using the calculated monitoring amount. That is, authentication device information in which the height from the floor surface of the object part to be authenticated by the authentication device and the threshold value indicating the lower limit value of the monitoring amount that can be authenticated by the authentication device is stored in the storage unit 11 in advance. Keep it. For example, the part of the object to be authenticated by the authentication apparatus is “person's face”, and the height is stored as 1.7 m. Further, as the lower limit value of the monitoring amount that can be authenticated by the authentication apparatus, the number of pixels of the face image that can be authenticated and the pixel density obtained from the approximate area of the face are stored. Then, the evaluation area setting unit 121 sets an evaluation area having an appropriate size (for example, a size corresponding to the head) at the height position, and the pixel number calculation unit 122 corresponds to the evaluation area. The number of pixels in the region is calculated, and the monitoring amount calculation unit 123 similarly calculates the monitoring amount in the evaluation region. More preferably, when calculating the monitoring amount, it is preferable not to consider the frame rate 113 and to calculate the sum of the monitoring amounts for each imaging device. Then, the monitoring amount image generation unit 124 generates an identification area image in which the evaluation area larger than the threshold value is displayed so as to be distinguishable from other spatial model areas, and the display area 13 displays and outputs the identification area image. To do. FIG. 11 is an example of an identification area image, and is an identification area image 41 when the vertically downward ground portion 33d of the evaluation area whose monitoring amount is larger than the threshold is displayed (filled display) so as to be distinguishable from other areas. is there. Thus, the administrator can grasp at a glance the area 33d that can be authenticated by the authentication apparatus in a wide monitoring space by looking at the identification area image 41.

  In the above embodiment, the imaging condition information 112 such as the installation position and orientation of the imaging device, the angle of view, and the resolution, and the frame rate 113 are stored in the storage unit 11 by being set and registered in advance by an administrator or the like. However, the present invention is not limited to this, and the imaging simulation apparatus 1 includes a communication unit that is a communication interface such as a wired LAN / wireless LAN or USB, and is connected to the imaging apparatus and a server apparatus that manages the imaging apparatus via the communication unit via a network connection. The imaging condition information 112 and the frame rate 113 may be received from these devices and stored in the storage unit 11. Thereby, for example, even when the attitude or angle of view of the imaging device is changed by an operation such as panning, tilting, or zooming by a camera controller, or when the imaging position of the imaging device mounted on the mobile robot is changed. The administrator can appropriately grasp the monitoring amount reflecting the change.

DESCRIPTION OF SYMBOLS 1 ... Imaging simulation apparatus 11 ... Memory | storage part 12 ... Control part 13 ... Display part 14 ... Input part 111 ... Spatial model 112 ... Imaging condition information 113 ... Frame rate 114 ... Evaluation area information 121 ... Evaluation area setting means 122 ... Number of pixels calculation means 123 ... Monitoring amount calculation means 124 ... Monitoring amount image generation means 30 ... Evaluation area 31 ... Corresponding area 32 ... Virtual camera 40 ... Monitoring amount image 41 ... Identification area image

Claims (6)

An imaging simulation apparatus for obtaining a monitoring amount representing a monitoring degree at a predetermined position in the monitoring space by one or a plurality of imaging apparatuses installed in the monitoring space,
Imaging including a space model expressing the monitoring space as a three-dimensional virtual space, information relating the installation position and orientation of the imaging device in the monitoring space to the virtual space, and the angle of view and resolution of the imaging device A storage unit for storing condition information;
An evaluation area including a position on the spatial model corresponding to the predetermined position is set, and an area corresponding to the evaluation area on a projection plane on which the spatial model is three-dimensionally projected from the imaging apparatus using the imaging condition information. A control unit that obtains the number of pixels and obtains the monitoring amount at the predetermined position from a ratio of pixels per unit area of the evaluation region using the number of pixels and an area corresponding to the evaluation region;
An output unit for outputting the monitoring amount;
An imaging simulation apparatus comprising: The storage unit further stores a frame rate of the imaging device,
The imaging simulation apparatus according to claim 1, wherein the control unit calculates the monitoring amount so as to increase as the frame rate increases. The storage unit further stores a depth of field of the imaging device,
The control unit calculates a distance from the installation position of the imaging device to a gravity center position of the evaluation area, and calculates so that the monitoring amount decreases as the distance deviates from the range of the depth of field. The imaging simulation apparatus according to claim 1 or 2. The control unit further generates a monitoring amount image in which a region of the spatial model corresponding to the evaluation region is represented by a color or shade corresponding to the monitoring amount,
The imaging simulation apparatus according to any one of claims 1 to 3, wherein the output unit displays and outputs the monitoring amount image. The storage unit further stores in advance a threshold value of the monitoring amount at a predetermined height,
The control unit further calculates the monitoring amount of the evaluation region at the height, and displays an evaluation region in which the monitoring amount is larger than the threshold so as to be distinguishable from other spatial model regions. Generate an image,
The imaging simulation apparatus according to claim 1, wherein the output unit displays and outputs the identification area image. A program for obtaining a monitoring amount representing a degree of monitoring at a predetermined position in the monitoring space by one or a plurality of imaging devices installed in the monitoring space,
Imaging including a space model expressing the monitoring space as a three-dimensional virtual space, information relating the installation position and orientation of the imaging device in the monitoring space to the virtual space, and the angle of view and resolution of the imaging device Condition information, and
The program is stored in a computer.
A process of setting an evaluation area including a position on the spatial model corresponding to the predetermined position, and corresponding to the evaluation area on a projection plane obtained by three-dimensionally projecting the spatial model from the imaging apparatus using the imaging condition information Processing for determining the number of pixels in the region, processing for determining the monitoring amount at the predetermined position from the ratio of pixels per unit area of the evaluation region using the number of pixels and the area corresponding to the evaluation region,
A program characterized by having executed.