JPWO2019107060A1 - Lighting control system and lighting control method - Google Patents

Abstract

A visual image acquisition unit (1) for acquiring a visual image and a viewpoint for inputting a visual field of a person, and converting the visible image acquired by the visual image acquisition unit (1) into a visual image of a human visual point in the visual field of the person. A conversion unit (4), a brightness distribution calculation unit (5) that calculates a brightness distribution of a human visual field based on a visible image of a human viewpoint that is converted by the viewpoint conversion unit (4), and a brightness distribution calculation unit (5). ), And a dimming control section (7) for controlling dimming of the luminaire based on the calculated luminance distribution of the human visual field.

Description

  The present invention relates to a lighting control system that detects a position of a person and a direction of the person from a visible image captured by a camera to appropriately adjust a lighting environment of a human visual field area.

  In order to optimize the lighting environment in an indoor space used by multiple people, conventionally, lighting equipment is based on the indoor illuminance measured by an illuminance sensor and the brightness distribution calculated from the image of the indoor space taken by a camera. Was controlling the dimming.

  For example, installing multiple cameras that capture images within the field of view of a person from different directions in the illumination space, measuring the luminance distribution within the range captured by the multiple cameras, and measuring the brightness distribution within the images captured by the multiple cameras. Detects the visual field direction of an existing person, controls the lighting fixtures based on the brightness distribution in the image of the detected visual field direction of the person, and performs lighting control that matches the sense of the person who is in the room. (For example, see Patent Document 1).

JP, 2010-9874, A (page 10-11, Drawing 1).

  However, in the technique described in Patent Document 1 described above, a human face must be detected from an image in order to detect the visual field direction of the human, and a plurality of cameras are installed in all directions so that the human face can be seen. Had to do. In addition, the brightness distribution used for dimming control is calculated by selecting an image in which the visual field direction of a person is taken from images taken by a plurality of cameras. Therefore, the image captured by the camera is an image with the camera installation position as the viewpoint, not the image of the field of view seen by the person from the viewpoint of the person. Therefore, it is necessary to accurately sense the lighting environment of the field of view of the person. However, there was a problem that the lighting environment created by controlling the lighting equipment based on the brightness distribution created from the image with the camera installation position as the viewpoint was not always comfortable for the person in the room. .

  This invention has been made to solve the above problems, and converts a visible image captured by a camera into a visible image that matches a human viewpoint, and calculates the luminance distribution of the visible image after the image conversion, An object of the present invention is to provide a lighting control system capable of controlling lighting by controlling lighting equipment based on this brightness distribution, without the need to install a plurality of cameras in all directions and obtaining a lighting space comfortable for humans.

  An illumination control system according to the present invention is input with a visible image acquisition unit that acquires a visible image and a visual field of a person, and converts the visible image acquired by the visible image acquisition unit into a visible image of a human viewpoint in the visual field. A viewpoint conversion unit, a brightness distribution calculation unit that calculates a brightness distribution of a visual field region based on a visible image of a human viewpoint, and a dimming control unit that controls dimming of a lighting device based on the brightness distribution are provided. Characterize.

  According to the present invention, a visible image captured by a visible camera installed on a ceiling or a wall surface of an indoor space is converted into an image that matches a human viewpoint, and a luminance distribution of the visible image after the image conversion is calculated. Since the lighting fixture is controlled based on the brightness distribution, it is not necessary to install a plurality of cameras in all directions, and lighting control that can provide a comfortable lighting space for humans can be performed.

It is a block diagram which shows the structure of the illumination control system which concerns on Embodiment 1 of this invention. 3 is a flowchart illustrating an operation of the lighting control system according to the first embodiment of the present invention. It is a figure which shows the relationship of a person's direction, a person's work area, and a person's visual field. It is a conceptual diagram of the image conversion process which the viewpoint conversion part of the illumination control system which concerns on Embodiment 1 of this invention performs. It is explanatory drawing explaining a scattering characteristic. It is explanatory drawing of the correction method of the luminance distribution of the illumination control system which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of another example of the illumination control system which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the illumination control system which concerns on Embodiment 2 of this invention. It is a block diagram which shows the structure of another example of the illumination control system which concerns on Embodiment 2 of this invention. It is a block diagram which shows the structure of the illumination control system which concerns on Embodiment 3 of this invention. It is explanatory drawing explaining the scattering characteristic in a different target surface. It is a block diagram which shows the structure of another example of the illumination control system which concerns on Embodiment 3 of this invention. It is a block diagram which shows the structure of the illumination control system which concerns on Embodiment 4 of this invention. It is a block diagram which shows the structure of the illumination control system which concerns on Embodiment 5 of this invention. It is a block diagram which shows the structure of another example of the illumination control system which concerns on Embodiment 5 of this invention. It is a flowchart explaining operation | movement of the illumination control system which concerns on Embodiment 5 of this invention. It is explanatory drawing explaining the operation | movement of the partition position estimation part in the lighting control system which concerns on Embodiment 5 of this invention.

Embodiment 1.
1 is a block diagram showing a configuration of an illumination control system according to a first embodiment for implementing the present invention. The illumination control system 100 according to the present embodiment includes a visible image acquisition unit 1, a viewpoint conversion unit 4, a brightness distribution calculation unit 5, and a dimming control unit 7.

  First, the configuration of the lighting control system according to the present embodiment will be described. A visible camera (not shown) for taking a visible image of the indoor space is installed at a position where the indoor space can be overlooked, for example, a ceiling, a pillar, or a wall. The visible camera photographs the interior space and outputs the photographed visible image to the visible image acquisition unit 1 together with the photographing time (imaging date and time). The visible image acquisition unit 1 outputs the acquired camera viewpoint visible image to the viewpoint conversion unit 4 together with the shooting time. The visible image acquired by the visible image acquisition unit 1 is a visible image whose viewpoint is the position where the visible camera is installed (hereinafter, referred to as camera viewpoint visible image). In addition, the visible image output by the viewpoint converting unit 4 is a visible image obtained by converting the viewpoint of the camera viewpoint visible image (hereinafter referred to as a human viewpoint visible image) so that the shooting viewpoint becomes the viewpoint of the person from the camera installation position. Is.

  The viewpoint conversion unit 4 inputs the camera viewpoint visible image from the visible image acquisition unit 1 and inputs the visual field region of a person who is a room occupant from the outside. An area that a person is looking at, that is, an area that is within the visual field of a person is defined as a visual field area of the person. The viewpoint conversion unit 4 extracts the visible image of the area corresponding to the human visual field from the entire area of the camera visual image, and changes the human visual point from the visual point of the camera installation position to the human visual point. Image conversion is performed by performing viewpoint conversion processing from the camera viewpoint visible image in the area corresponding to the visual field area to the human viewpoint visible image. That is, the viewpoint conversion unit 4 performs image conversion of the camera viewpoint visible image into the human viewpoint visible image in the human visual field. The viewpoint conversion unit 4 outputs the human viewpoint visible image after the image conversion to the brightness distribution calculation unit 5.

  The brightness distribution calculation unit 5 calculates the brightness distribution in the visual field region based on the human viewpoint visible image input from the viewpoint conversion unit 4. Then, the brightness distribution calculation unit 5 calculates the light scattering characteristics (hereinafter, referred to as scattering characteristics) of the partial regions forming the human viewpoint visible image input from the outside and the human viewpoint visible image input from the viewpoint conversion unit 4. The luminance distribution in the visual field region is corrected based on the direction of the human eye for each partial region inside. The brightness distribution calculation unit 5 outputs the brightness distribution in the corrected visual field area to the dimming control unit 7. The dimming control unit 7 controls dimming of the lighting fixture based on the brightness distribution input from the brightness distribution calculating unit 5.

  Next, the operation will be described. FIG. 2 is a flowchart illustrating the operation of the lighting control system according to the first embodiment of the present invention. The visible camera captures a current camera viewpoint visible image. The visible image acquisition unit 1 acquires a camera viewpoint visible image captured by a visible camera (step S1). As the visible camera, a fish-eye visible camera having a wide angle of view, which is equipped with a lens having a field angle of 180 degrees or more, which is generally called a fish-eye lens, is used. However, it is preferable that the angle of view is 180 degrees or more in order to acquire image information of a wide range, but it may be 180 degrees or less.

  When a fish-eye visible camera is used, the amount of light in the peripheral region of the acquired image is less than that in the central region, so the brightness is calculated to be small. Therefore, it is possible to calculate the luminance distribution more accurately by correcting the shortage. The correction amount depends on the characteristics of the camera lens and the light receiving element. Therefore, it is preferable to prepare the correction data in which the correction amount for each partial area is described for each camera. The method of calculating the correction data is as follows. A luminance distribution is created from a fisheye visible image taken by a fisheye visible camera. Using a luminance meter or a spectral radiance meter used for illumination measurement, the actually measured luminance of the subject displayed in the fisheye visible image is measured for each partial area. The correction data can be calculated from the correction coefficient of the brightness distribution and the actually measured brightness.

  FIG. 3 is a diagram showing a relationship between a person's orientation, a person's work area, and a person's visual field, which is a part of a camera viewpoint visible image captured by a visible camera installed on a ceiling. In FIG. 3, d1 indicates a person reflected in a visible image from a camera viewpoint, a region indicated by d2 indicates a work area of the person, a region indicated by d3 indicates a visual field of the person, and an arrow d4 indicates a direction of the person. The work area of a person is, for example, a desk top surface. The black circular area of d1 shows the person's head, and the hatched area around the black circle shows the upper body of the person, mainly the arms.

  Next, the viewpoint conversion unit 4 inputs a human visual field from the outside (step S2). For example, the position of a person and the direction of the person are estimated based on the arrangement of a desk or a chair installed in the indoor space, and the visual field area of the person is estimated in advance based on the position of the person and the direction of the person. You may stay. Alternatively, the position of a person may be detected from a thermal image of the same space captured by an infrared camera or the like, and the visual field area of the person may be estimated based on the information on the position of the person.

  Next, the viewpoint conversion unit 4 extracts the visible image of the area corresponding to the human visual field from the entire area of the camera visual image. Then, the viewpoint conversion unit 4 performs viewpoint conversion processing from the camera viewpoint visible image in the area corresponding to the human visual field to the human viewpoint visible image so that the shooting viewpoint becomes the human viewpoint from the camera installation position viewpoint, Image conversion is performed (step S3).

  FIG. 4 is a conceptual diagram of image conversion processing performed by the viewpoint conversion unit 4. FIG. 4A is a camera viewpoint visible image when the angle of view is 180 degrees, and is a camera viewpoint visible image captured with the shooting viewpoint as the viewpoint of the camera installation position. In FIG. 4A, the area indicated by d3 corresponds to the human visual field area d3 shown in FIG. FIG. 4B is a human-view visible image obtained by image-converting the camera-view visible image so that the shooting viewpoint becomes the human's viewpoint from the viewpoint of the camera installation position. The human visual field shown by d3 in FIG. 4A corresponds to the entire area of FIG. 4B. The viewpoint conversion unit 4 cuts out a region corresponding to d3 from the camera viewpoint visible image, and then performs coordinate conversion processing on the cut image so that the shooting viewpoint becomes the human viewpoint from the camera installation position. By the coordinate conversion processing, the viewpoint conversion processing can be performed from the camera viewpoint visible image in the area corresponding to the human visual field to the human viewpoint visible image.

  A coordinate conversion table may be held in advance for each of a plurality of partial areas forming the camera viewpoint visible image, and the coordinate conversion processing may be performed using the coordinate conversion table. Alternatively, the coordinate conversion process may be performed by smoothly deforming the visual field region from the center to the peripheral portion so that the visual field region becomes rectangular. A sensor that can acquire depth information may be installed at the visible camera installation position, and the coordinate conversion table may be created using the depth information.

  The human viewpoint visible image image-converted by the viewpoint converting unit 4 is input to the brightness distribution calculating unit 5. The luminance distribution calculation unit 5 calculates the luminance distribution in the visual field region based on the human visual point visible image image-converted by the visual point conversion unit 4 and the scattering characteristics of each partial region forming the human visual point visible image input from the outside. Calculate (step S4).

  Here, the scattering characteristics will be described. FIG. 5 is an explanatory diagram illustrating the scattering characteristics. There are three main types of scattering characteristics corresponding to the characteristics of the target surface (reflection surface). The first is a uniform diffuse reflection surface that diffuses uniformly in all directions shown in FIG. The brightness of the target surface is constant when viewed from any direction. The second is the mirror surface shown in FIG. Light having the same brightness as the light source enters only when the target surface is viewed from the reflection angle direction having the same angle as the incident angle to the target surface, that is, the regular reflection direction. No light enters even if the target surface is viewed from other directions. The third is the scattering surface shown in FIG. The scattering surface has the properties of both a uniform diffuse reflection surface and a mirror surface, with high brightness in the regular reflection direction, and an intensity distribution close to that of a uniform diffusion reflection surface in other cases.

Next, the calculation of the brightness distribution will be described. Each pixel of the visible image has the value of each signal of R (Red), G (Green), and B (Blue). First, a brightness image in which the brightness of each pixel is calculated from the R, G, and B values is generated. The brightness Y is calculated using the equation (1).
Y = 0.257R + 0.504G + 0.098B + 16 (1)
Note that the average luminance of each partial area of the human visual point visible image may be calculated and used as the luminance distribution.

  Then, the brightness is corrected based on the scattering characteristic. FIG. 6 is an explanatory diagram of a method of correcting the brightness distribution. FIG. 6 shows the relationship between the scattering characteristics of the target surface and the visible camera and the viewpoint of the person. The broken line arrow in FIG. 6 indicates the intensity distribution of the scattering characteristic. The scattering characteristic of the target surface that has been acquired in advance or the scattering characteristic estimated by measuring with a visible camera is used. When converting to a luminance distribution from an arbitrary viewpoint P, a luminance ratio B / A, which is a ratio between the luminance A in the visible camera direction and the luminance B in the viewpoint direction, is calculated based on the scattering characteristic, and the luminance ratio is used as a correction coefficient. By multiplying the brightness for each partial area calculated from the human viewpoint visible image, a more accurate brightness distribution from an arbitrary viewpoint P can be calculated. When the scattering characteristic is output to the brightness distribution calculation unit 5 with the entire area of the camera viewpoint visible image as uniform diffuse reflection, the correction coefficient (brightness ratio) is 1.

  An image that can be captured by a visible camera has a limited range of luminance that can be acquired depending on the exposure setting during capturing. Further, since the gradations of R, G, and B values of each pixel are limited to 256 gradations and the like, in order to measure the luminance correctly, it is necessary to take a plurality of visible images with different exposures and combine them. is necessary. In this case, the visible image acquisition unit 1 acquires a plurality of visible images captured by the visible camera with different exposure settings. The viewpoint conversion unit 4 performs a viewpoint conversion process on each visible image. Then, the luminance distribution calculation unit 5 calculates the luminance distribution and corrects the scattering characteristics for each view-converted visible image, and adds up the corrected luminance distributions to obtain the luminance in the visual field region. The distribution is output to the dimming control unit 7.

  The dimming control unit 7 performs the dimming control of the indoor space based on the brightness distribution calculated by the brightness distribution calculating unit 5 so that an illumination space that a person feels comfortable in the human visual field can be obtained. When performing the dimming control, the dimming control unit 7 identifies the lighting fixture to be dimmed among the lighting fixtures installed on the ceiling, the wall, the pillar, etc. of the indoor space (step S5). Then, the dimming control unit 7 individually adjusts the illuminance of each of the identified lighting fixtures to perform dimming control (step S6).

  FIG. 7 is a block diagram showing the configuration of another example of the lighting control system according to Embodiment 1 of the present invention. In the illumination control system 110 shown in FIG. 7, the brightness of the visual field area is estimated based on the luminance distribution of the visual field area instead of performing the dimming control based on the luminance distribution of the visual field area. It is configured to perform dimming control based on the above.

  In FIG. 7, the brightness estimation unit 6 estimates the brightness of the indoor space based on the brightness distribution in the visual field area input from the brightness distribution calculation unit 5. The brightness estimation unit 6 calculates the brightness from the brightness distribution with respect to the brightness of each partial area of the human-view visible image or the brightness distribution of the entire human-view visible image. The index indicating brightness includes, for example, average brightness, average illuminance, and sense of brightness. The sense of brightness is an index of brightness that considers the effect of the comparison with the ambient brightness on how people feel, and a known technique is used for estimating the brightness based on the brightness distribution. The brightness estimation unit 6 outputs the estimated brightness to the dimming control unit 7.

  The dimming control unit 7 performs the dimming control of the indoor space based on the brightness calculated by the brightness estimating unit 6 so that an illumination space that a person feels comfortable in the visual field of the person can be obtained. When performing the dimming control, the dimming control unit 7 identifies a lighting fixture to be dimmed among the lighting fixtures installed on the ceiling, the wall, the pillar, etc. of the indoor space. Then, the dimming control unit 7 individually adjusts the illuminance of each specified lighting fixture to perform dimming control.

  For example, when the brightness is controlled using the average illuminance, the dimming control unit 7 sets a lighting device existing in the visual field area of the person or around the visual field area of the person as a control target and averaging. Dimming the luminaire so that the illuminance approaches the desired value. Then, in the illumination control system 110, the operations from the acquisition of the visible image by the visible image acquisition unit 1 to the dimming control by the dimming control unit 7 are performed until the brightness estimated by the brightness estimating unit 6 reaches a desired value. repeat. The desired value is, for example, 500 lux for the work area and 300 lux for the visual field area other than the work area. When the work area can be specified such as the desk top surface of an office, it is possible to provide a lighting environment satisfying the JIS (Japan Industrial Standards) illuminance standard with the lighting control system of the present invention.

  The visible camera may be a normal visible camera instead of the fisheye visible camera. The visible image acquisition unit 1 may combine visible images acquired by a plurality of visible cameras to create a visible image of a wider space.

  In addition, the visible image captured and output by the visible camera may be an image that has been subjected to image processing in the camera, and if the luminance is significantly corrected by the image processing, there is a problem that the luminance cannot be correctly estimated. Before installing a visible camera, measure the brightness value of the subject at multiple points using a luminance meter or spectral radiance meter used for lighting measurement, estimate the image processing characteristics of the visible camera, and obtain a visible image. The image processing characteristic may be inversely corrected and output from the visible image acquisition unit 1 using the brightness value measured later.

  In the illumination control system according to the present embodiment configured as described above, the image conversion from the camera viewpoint visible image to the human viewpoint visible image, and the luminance distribution and the brightness are estimated based on the human viewpoint visible image. It is possible to estimate the brightness of the indoor space with a smaller number of sensors than to estimate the brightness of the indoor space using the sensor. Then, by performing the dimming control based on the current brightness, it is possible to provide an effect that a lighting space that is comfortable for a person can be provided. Even when daylight enters the indoor space, the effect of being able to provide the designated illumination environment can be obtained by similarly adjusting the light intensity based on the current brightness.

Embodiment 2.
FIG. 8 is a block diagram showing the configuration of the illumination control system according to the second embodiment for implementing the present invention. Illumination control system 200 according to the present embodiment includes visible image acquisition unit 1, person position / orientation detection unit 2, visual field region estimation unit 3, viewpoint conversion unit 4, brightness distribution calculation unit 5, and dimming control. And a control unit 7. In the present embodiment, the human position / orientation detection unit 2 and the visual field region estimation unit 3 are provided, the visual field region of the person is estimated from the visible image acquired by the visible image acquisition unit 1, and the estimated human visual field region is calculated. It differs from the first embodiment in that it is input to the viewpoint conversion unit 4.

  First, the configuration of the lighting control system according to the present embodiment will be described. Similar to the first embodiment, a visible camera (not shown) for taking a visible image of the indoor space is installed at a position where the indoor space can be overlooked, for example, a ceiling, a pillar, or a wall. The visible camera photographs the interior space and outputs the photographed visible image to the visible image acquisition unit 1 together with the photographing time. The visible image acquisition unit 1 outputs the acquired camera viewpoint visible image to the person position / orientation detection unit 2 and the viewpoint conversion unit 4 together with the shooting time.

  The human position / orientation detection unit 2 receives the camera viewpoint visible image from the visible image acquisition unit 1 and detects the position and orientation of the person present in the indoor space from the camera viewpoint visible image.

  The visual field estimation unit 3 determines the visual field of a person based on the camera viewpoint visible image input from the human position / orientation detecting unit 2 and the position and orientation of the person detected by the human position / orientation detecting unit 2. It estimates and outputs the visual field area in the camera visual point visible image to the visual point conversion unit 4.

  The viewpoint conversion unit 4 inputs the camera viewpoint visible image from the visible image acquisition unit 1, and inputs the visual field region of the person who is the occupant from the visual field region estimation unit 3. The viewpoint conversion unit 4 extracts the visible image of the area corresponding to the human visual field from the entire area of the camera visual image, and changes the human visual point from the visual point of the camera installation position to the human visual point. Image conversion is performed by performing viewpoint conversion processing from the camera viewpoint visible image in the area corresponding to the visual field area to the human viewpoint visible image. That is, the viewpoint conversion unit 4 performs image conversion of the camera viewpoint visible image into the human viewpoint visible image in the human visual field. The viewpoint conversion unit 4 outputs the human viewpoint visible image after the image conversion to the brightness distribution calculation unit 5.

  The luminance distribution calculation unit 5 calculates the luminance distribution in the visual field region based on the human visual point visible image input from the visual point conversion unit 4, and scatter characteristics for each partial region forming the human visual point image input from the outside. And the luminance distribution in the visual field region based on the visual point direction for each partial region in the human visual point visible image input from the visual point conversion unit 4. The brightness distribution calculation unit 5 outputs the brightness distribution in the corrected visual field area to the dimming control unit 7. The dimming control unit 7 controls dimming of the lighting fixture based on the brightness distribution input from the brightness distribution calculating unit 5.

  Next, the operation will be described. The visible camera captures a current camera viewpoint visible image. The visible image acquisition unit 1 acquires a camera viewpoint visible image captured by a visible camera. First, the camera viewpoint visible image is input to the person position / orientation detecting unit 2. The person position / orientation detection unit 2 detects a person based on a camera viewpoint visible image. A known technique is used as a method for detecting a person from an image. For example, it is possible to detect a person from an image by holding a pattern image of the shape of a person as a database and performing pattern matching. However, since the visible camera is installed at a position where the interior space can be overlooked, even when a person is shown in the visible image, it is rare that the face of the person is seen at a resolution that can be recognized. Therefore, the shape of the upper body of the head and body when viewed from a high position of a pillar or a wall (higher than the height of a person) or from the ceiling is used as a pattern image. When the person is detected from the camera viewpoint visible image, the person position / orientation detecting unit 2 detects the coordinates of one point included in the area where the detected person is shown as the person's position. For example, the coordinates of the center of the head are detected as the position of the person. As the visible camera, a fish-eye visible camera having a wide angle of view, which is equipped with a lens having a field angle of 180 degrees or more, which is generally called a fish-eye lens, is used. However, it is preferable that the angle of view is 180 degrees or more in order to acquire image information of a wide range, but it may be 180 degrees or less.

  Then, the person position / orientation detecting unit 2 detects the orientation of the person. The person d1, the person's work area d2, the person's visual field area d3, and the person's direction d4 reflected in the camera viewpoint visible image are as shown in FIG. When a person uses his / her hands to work, his / her arm is in front of the head, so that the orientation of the person can be identified by the positional relationship between the head and the arm. Using this, the person position / orientation detection unit 2 detects d4, which is the orientation of the person. The direction of a person is represented by a vector from the coordinates of the person's position. The position and orientation of the person detected by the person position / orientation detection unit 2 and the camera viewpoint visible image input from the visible image acquisition unit 1 to the person position / orientation detection unit 2 are input to the visual field region estimation unit 3. To be done.

  The visual field region estimation unit 3 estimates the visual field region of the person shown in d3 of FIG. 3 from the camera visual point visible image. An area that a person is looking at, that is, an area that is within the visual field of a person is defined as a visual field area of the person. The visual field of the person is an area of about 180 degrees in the horizontal direction centered on d4, which is the direction in which the person is facing. The field of view of a person includes the area shown in the visible image from the camera's viewpoint in the direction in which the person is facing from the position of the person, unless there are obstacles such as partitions and shelves that are high enough to block the view of the person. Be done. Further, depending on the position of the person in the camera viewpoint visible image, image conversion may be performed so that the field of view becomes semicircular when the position of the person is taken as the viewpoint.

  The human visual field estimated by the visual field estimation unit 3 is input to the viewpoint conversion unit 4. The visual field area input to the visual point conversion unit 4 is an area corresponding to the visual field area of a person in the camera visual point visible image. The viewpoint conversion unit 4 first extracts a visible image of a region corresponding to a human visual field from all regions of the camera viewpoint visible image acquired by the visible image acquisition unit 1. Next, the camera viewpoint visible image in the area corresponding to the human visual field is converted into the human viewpoint visible image so that the photographing viewpoint becomes the human viewpoint from the camera installation position.

  The d3 shown in FIG. 3 described in the first embodiment is the human visual field estimated by the visual field estimation unit 3. The viewpoint conversion unit 4 cuts out a region corresponding to d3 from the camera viewpoint visible image, and then performs coordinate conversion processing on the cut image so that the shooting viewpoint becomes the human viewpoint from the camera installation position. By the coordinate conversion processing, the viewpoint conversion processing can be performed from the camera viewpoint visible image in the area corresponding to the human visual field to the human viewpoint visible image.

  A coordinate conversion table may be held in advance for each of a plurality of partial areas forming the camera viewpoint visible image, and the coordinate conversion processing may be performed using the coordinate conversion table. Alternatively, the coordinate conversion process may be performed by smoothly deforming the visual field region from the center to the peripheral portion so that the visual field region becomes rectangular. A sensor that can acquire depth information may be installed at the visible camera installation position, and the coordinate conversion table may be created using the depth information.

  The human viewpoint visible image image-converted by the viewpoint converting unit 4 is input to the brightness distribution calculating unit 5. The brightness distribution calculation unit 5 calculates the brightness distribution in the visual field region from the human visual point visible image image-converted by the visual point conversion unit 4. Specifically, each pixel of the visible image has a value of each signal of R, G, and B, and the luminance of each pixel is calculated from each value of R, G, B to generate a luminance image.

  The luminance distribution calculation unit 5 calculates the luminance distribution in the visual field region based on the human visual point visible image image-converted by the visual point conversion unit 4 and the scattering characteristics of each partial region forming the human visual point visible image input from the outside. calculate. The method of calculating the luminance distribution is the same as that described in the first embodiment. The brightness distribution calculator 5 outputs the brightness distribution in the visual field area to the dimming controller 7.

  The dimming control unit 7 performs the dimming control of the indoor space based on the brightness distribution calculated by the brightness distribution calculating unit 5 so that an illumination space that a person feels comfortable in the human visual field can be obtained. When performing the dimming control, the dimming control unit 7 identifies a lighting fixture to be dimmed among the lighting fixtures installed on the ceiling, the wall, the pillar, etc. of the indoor space. Then, the dimming control unit 7 individually adjusts the illuminance of each of the identified lighting fixtures to perform dimming control.

  FIG. 9 is a block diagram showing the configuration of another example of the illumination control system according to the second embodiment of the present invention. In the illumination control system 210 shown in FIG. 9, the brightness of the visual field is estimated based on the luminance distribution of the visual field, instead of performing the dimming control based on the luminance distribution of the visual field. It is configured to perform dimming control based on the above.

  In FIG. 9, the brightness estimating unit 6 estimates the brightness of the indoor space based on the brightness distribution in the visual field area input from the brightness distribution calculating unit 5. The brightness estimation unit 6 calculates the brightness from the brightness distribution with respect to the brightness of each partial area of the human-view visible image or the brightness distribution of the entire human-view visible image. The index indicating brightness includes, for example, average brightness, average illuminance, and sense of brightness. The sense of brightness is an index of brightness that considers the effect of the comparison with the ambient brightness on how people feel, and a known technique is used for estimating the brightness based on the brightness distribution. In this case, since a plurality of brightness distributions taken with different exposure settings are required, it is preferable to change the exposure at the time of shooting a visible image with the visible camera. The brightness estimation unit 6 outputs the estimated brightness to the dimming control unit 7.

  The dimming control unit 7 performs the dimming control of the indoor space based on the brightness calculated by the brightness estimating unit 6 so that an illumination space that a person feels comfortable in the visual field of the person can be obtained. When performing the dimming control, the dimming control unit 7 identifies a lighting fixture to be dimmed among the lighting fixtures installed on the ceiling, the wall, the pillar, etc. of the indoor space. Then, the dimming control unit 7 individually adjusts the illuminance of each specified lighting fixture to perform dimming control.

  For example, when the brightness is controlled using the average illuminance, the dimming control unit 7 sets a lighting device existing in the visual field area of the person or around the visual field area of the person as a control target and averaging. Dimming the luminaire so that the illuminance approaches the desired value. Then, in the illumination control system 210, the operations from the acquisition of the visible image by the visible image acquisition unit 1 to the dimming control by the dimming control unit 7 are performed until the brightness estimated by the brightness estimating unit 6 reaches a desired value. repeat. The desired value is, for example, 500 lux for the work area and 300 lux for the visual field area other than the work area. When the work area can be specified such as the desk top surface of an office, it is possible to provide a lighting environment satisfying the JIS illuminance standard with the lighting control system of the present invention.

  The visible camera may be a normal visible camera instead of the fisheye visible camera. The visible image acquisition unit 1 may combine visible images acquired by a plurality of visible cameras to create a visible image of a wider space.

  In addition, the visible image captured and output by the visible camera may be an image that has been subjected to image processing in the camera, and if the luminance is significantly corrected by the image processing, the luminance cannot be correctly estimated. . Before installing a visible camera, measure the brightness value of the subject at multiple points using a luminance meter or spectral radiance meter used for lighting measurement, estimate the image processing characteristics of the visible camera, and obtain a visible image. The image processing characteristic may be inversely corrected and output from the visible image acquisition unit 1 using the brightness value measured later.

  In the illumination control system according to the present embodiment configured as described above, image conversion is performed from a camera viewpoint visible image to a human viewpoint visible image, and the luminance distribution and brightness are estimated based on the human viewpoint visible image. It is possible to estimate the brightness of the indoor space with a smaller number of sensors than to estimate the brightness of the indoor space using the sensor. Then, by performing the dimming control based on the current brightness, it is possible to provide an effect that a lighting space that is comfortable for a person can be provided. Even when daylight enters the indoor space, the effect of being able to provide the designated illumination environment can be obtained by similarly adjusting the light intensity based on the current brightness.

  Further, since the position of the person and the direction of the person are detected from the visible image, the visual field area of the person can be estimated. Also, since the brightness distribution and brightness are estimated after converting the image of the visible camera installation position viewpoint image to the human viewpoint image, it is possible to more accurately estimate the brightness felt by a person, and By performing the dimming control based on the brightness that a person feels, an effect that a comfortable illumination space for a person can be provided can be obtained. Further, even when daylight enters the indoor space, a desired lighting environment can be provided by adjusting the lighting based on the brightness felt by the person currently in the room.

Embodiment 3.
FIG. 10 is a block diagram showing the configuration of the illumination control system according to the third embodiment for implementing the present invention. Illumination control system 300 according to the present embodiment includes visible image acquisition unit 1, person position / orientation detection unit 2a, visual field region estimation unit 3, viewpoint conversion unit 4, brightness distribution calculation unit 5, and dimming control. A unit 7, an image storage unit 8, a scattering characteristic estimation unit 9, and a second viewpoint conversion unit 14 are provided. The difference from the second embodiment is that the image storage unit 8, the scattering characteristic estimation unit 9, and the second viewpoint conversion unit 14 are provided.

  First, the configuration of the lighting control system according to the present embodiment will be described. A visible camera (not shown) for taking a visible image of the indoor space is installed at a position where the indoor space can be overlooked, for example, a ceiling, a pillar, or a wall. The visible camera photographs the interior space and outputs the photographed visible image to the visible image acquisition unit 1 together with the photographing time. The visible image acquisition unit 1 outputs the acquired camera viewpoint visible image to the person position / orientation detection unit 2a, the viewpoint conversion unit 4, the image storage unit 8, and the scattering characteristic estimation unit 9 together with the shooting time.

  The image storage unit 8 stores the camera viewpoint visible image acquired by the visible image acquisition unit 1 and the shooting time of the camera viewpoint visible image. The image storage unit 8 outputs the camera viewpoint visible image at the photographing time designated by the person position / orientation detection unit 2a to the person position / orientation detection unit 2a. Further, the image storage unit 8 outputs the camera viewpoint visible image at the photographing time designated by the scattering characteristic estimating unit 9 to the scattering characteristic estimating unit 9.

  The human position / orientation detection unit 2a determines the position of a person present in the indoor space from the camera viewpoint visible image acquired by the visible image acquisition unit 1 and the camera viewpoint visible image stored in the image storage unit 8. Detects the direction of a person. The visible image from the camera obtained by the visible image acquisition unit 1 and the position and orientation of the person who is in the room are output to the visual field region estimation unit 3.

  The visual field region estimation unit 3 is based on the camera viewpoint visible image input from the person position / orientation detection unit 2a and the position and orientation of the person in the camera viewpoint visible image detected by the person position / orientation detection unit 2a. The visual field area of the person is estimated and the visual field area in the camera visual point visible image is output to the visual point conversion unit 4.

  The viewpoint conversion unit 4 inputs the camera viewpoint visible image from the visible image acquisition unit 1, and inputs the visual field region of the person who is the occupant from the visual field region estimation unit 3. The viewpoint conversion unit 4 extracts the visible image of the area corresponding to the human visual field from the entire area of the camera visual image, and changes the human visual point from the visual point of the camera installation position to the human visual point. Image conversion is performed by performing viewpoint conversion processing from the camera viewpoint visible image in the area corresponding to the visual field area to the human viewpoint visible image. That is, the viewpoint conversion unit 4 performs image conversion of the camera viewpoint visible image into the human viewpoint visible image in the human visual field. The viewpoint conversion unit 4 outputs the human viewpoint visible image after the image conversion to the brightness distribution calculation unit 5.

  The scattering characteristic estimation unit 9 extracts a plurality of camera viewpoint visible images having different photographing times from the camera viewpoint visible images acquired by the visible image acquisition unit 1 and the camera viewpoint visible images stored in the image storage unit 8. A scattering characteristic is estimated for each of a plurality of partial areas forming the camera viewpoint visible image acquired by the visible image acquisition unit 1. Then, the second viewpoint conversion unit 14 outputs the scattering characteristics obtained by performing the viewpoint conversion processing from the camera viewpoint visible image to the human viewpoint visible image to the luminance distribution calculation unit 5.

  The luminance distribution calculation unit 5 calculates the luminance distribution in the visual field region based on the human viewpoint visible image input from the viewpoint conversion unit 4, and constitutes the human viewpoint visible image input from the second viewpoint conversion unit 14. The brightness distribution in the visual field area is corrected based on the scattering characteristics for each area and the visual point direction for each partial area in the human visual point visible image input from the visual point conversion unit 4. The corrected luminance distribution in the visual field area is output to the dimming control unit 7. The dimming control unit 7 controls dimming of the lighting fixture based on the brightness distribution input from the brightness distribution calculating unit 5.

  Next, the operation will be described. Among the constituent elements in the present embodiment, the visible image acquisition unit 1, the visual field region estimation unit 3, the viewpoint conversion unit 4, the brightness distribution calculation unit 5, and the dimming control, which are assigned the same reference numerals as those in the second embodiment. Since the unit 7 operates in the same manner as in the second embodiment, the description thereof will be omitted in the present embodiment.

  The visible camera captures a current camera viewpoint visible image. The visible image acquisition unit 1 acquires a camera viewpoint visible image captured by a visible camera. The camera viewpoint visible image acquired by the visible image acquisition unit 1 is input to the image storage unit 8 together with the shooting time. The image storage unit 8 stores the camera viewpoint visible image and the shooting time. When the image storage unit 8 receives a request from the human position / orientation detection unit 2a to output a camera viewpoint visible image at the shooting time designated by the human position / orientation detection unit 2a, it outputs the camera viewpoint visible image at the corresponding shooting time. It is output to the position / direction detector 2a. Further, when the image storage unit 8 receives a request from the scattering characteristic estimating unit 9 to output a camera viewpoint visible image at the photographing time designated by the scattering characteristic estimating unit 9, the image accumulation unit 8 scatters the camera viewpoint visible image at the corresponding photographing time. Output to the estimation unit 9.

  The person position / orientation detection unit 2a uses the camera viewpoint visible image acquired by the visible image acquisition unit 1 and the camera viewpoint visible image stored in the image storage unit 8 to detect the position and the person of the person in the room. To detect the direction of. The person position / orientation detection unit 2a requests the image storage unit 8 to output a camera viewpoint visible image whose shooting time is several minutes to several tens of minutes before the shooting time acquired by the visible image acquisition unit 1. The person position / orientation detection unit 2a calculates a difference value between two camera viewpoint visible images. An area in which the difference value is larger than the peripheral pixels is detected as a person, and the coordinates of one point in the area are set as the person's position. As a method for detecting the orientation of the person, the same method as the detection method performed by the person position / orientation detecting unit 2 of the second embodiment is used. Further, as the method of estimating the visual field region, the same method as the estimation method performed by the visual field region estimation unit 3 of the second embodiment is used.

  The scattering characteristic estimation unit 9 estimates the scattering characteristic of the projected subject for each partial region forming the camera viewpoint visible image using a plurality of camera viewpoint visible images at different photographing times. First, the scattering characteristic estimation unit 9 requests the image storage unit 8 to output a camera viewpoint visible image at a shooting time when the position of the light source is different. The photographing times at which the positions of the light sources are different are, for example, when the light source is daylight, the times at fixed time intervals from the sunrise time to the sunset time. In addition, when a light source installed in a room is used as the light source, it is the lighting time of the light source where the angle of the light hitting the subject is different. Note that the scattering characteristics can be more accurately estimated when the number of visible images from the camera viewpoint is large.

  FIG. 11 is an explanatory diagram illustrating the scattering characteristics on different target surfaces. A method for estimating the scattering characteristic will be described with reference to FIG. Each drawing of FIG. 11 shows the brightness of the light entering the visible camera when the light from the light source reflected by the target surface is photographed by the visible camera. The dashed arrows in the figure represent the intensity distribution of the scattering characteristics. In FIG. 11, (a1), (a2) and (a3), (b1), (b2) and (b3), (c1), (c2) and (c3) are the same target surface.

  The target surfaces of (a1), (a2), and (a3) of FIG. 11 do not depend on the position of the light source, and the brightness entering the visible camera is constant. At this time, the scattering characteristic of the target surface is estimated to be a uniform diffuse reflection surface. In the target surfaces of (b1), (b2), and (b3) of FIG. 11, light enters the visible camera only in the case of (b2). At this time, the scattering characteristic of the target surface is estimated to be a mirror surface that reflects light only in a specific direction, and is stored in the scattering characteristic estimation unit 9 as the scattering characteristic together with the direction of specular reflection. In the target surfaces of (c1), (c2), and (c3) of FIG. 11, the brightness captured by the visible camera differs depending on the position of the light source. At this time, the target surface is estimated to be a scattering surface, and based on the incident direction of the light source and the brightness obtained by the visible camera, the reflection characteristics of the target surface (the direction in which light is reflected and the intensity distribution of reflected light) are generated, The scattering characteristic is stored in the scattering characteristic estimation unit 9.

  The scattering characteristic estimating unit 9 may output the scattering characteristic to the luminance distribution calculating unit 5 without estimating the scattering characteristic, using the entire region of the camera-view visible image as a uniform diffuse reflection surface.

  Since the scattering characteristic is determined by the material of the object, the scattering characteristic estimating unit 9 does not change the scattering characteristic when the article installed in the indoor space photographed by the visible camera does not change. Therefore, the scattering characteristic estimation unit 9 temporarily estimates the scattering characteristic of the entire area of the camera viewpoint visible image and accumulates the scattering characteristics, so that the scattering characteristics are calculated every time the camera viewpoint image is input from the visible image acquisition unit 1. It is not necessary to estimate the characteristics. When the scattering characteristic is output to the brightness distribution calculation unit 5 with the entire area of the camera viewpoint visible image as uniform diffuse reflection, the correction coefficient (brightness ratio) is 1.

  Note that the scattering property estimation unit 9 estimates the scattering property for each partial region for the entire region of the camera viewpoint visible image, but the invention is not limited to this, and the visual field region is acquired from the visual field region estimation unit 3 to obtain the visual field region. The scattering characteristics may be estimated only for. However, in this case, it is necessary to estimate the scattering characteristic each time a visible image from the camera viewpoint is input from the visible image acquisition unit 1. The scattering characteristic estimated by the scattering characteristic estimating unit 9 is subjected to the viewpoint converting process from the camera viewpoint visible image to the human viewpoint visible image in the second viewpoint converting unit 14, and is output to the luminance distribution calculating unit 5. The viewpoint conversion processing in the second viewpoint conversion unit 14 is the same as that of the viewpoint conversion unit 4.

  Further, the scattering characteristic estimation unit 9 creates a database of the light distribution and luminous flux amount of the lighting fixtures installed at a plurality of locations in the indoor space, and then instructs the dimming control unit 7 to individually light each lighting fixture. In this way, the intensity of the light reflected from each lighting fixture and the target surface is acquired. Then, the scattering characteristic estimation unit 9 estimates the angle of incidence and the angle of emission from the target surface from the positional relationship among the lighting fixture, the target surface, and the visible image acquisition unit 1, and estimates the scattering characteristic as shown in FIG. You can also In that case, in order to improve the accuracy of the luminous flux emitted from the lighting fixture, it is more preferable to dispose an optical sensor. Here, the target surface is, for example, a desk top surface.

  The brightness distribution calculation unit 5 calculates the human visual point view image input from the visual point conversion unit 4 and the scattering characteristic of each partial area forming the human visual point visible image input from the scattering characteristic estimation unit 9 within the visual field area. The brightness distribution is calculated and output to the dimming control unit 7. The dimming control unit 7 controls dimming of the lighting fixture based on the brightness distribution input from the brightness distribution calculating unit 5.

  FIG. 12 is a block diagram showing the configuration of another example of the lighting control system according to Embodiment 3 of the present invention. The illumination control system 310 shown in FIG. 12 does not perform the dimming control based on the luminance distribution of the visual field area, but estimates the brightness of the visual field area based on the luminance distribution of the visual field area and determines the brightness of the visual field area. It is configured to perform dimming control based on the above. The brightness estimating unit 6 is added, and the scattering characteristic estimating unit 9 is changed to the scattering characteristic / reflectance estimating unit 19.

  The scattering characteristic / reflectance estimation unit 19 uses the camera viewpoint visible images acquired by the visible image acquisition unit 1 and the camera viewpoint visible images accumulated in the image accumulating unit 8 to obtain a plurality of camera viewpoint visible images having different photographing times. And the scattering characteristic and the reflectance are estimated for each of the plurality of partial regions forming the camera viewpoint visible image acquired by the visible image acquiring unit 1. Then, the second viewpoint conversion unit 14 performs viewpoint conversion processing from the camera viewpoint visible image to the human viewpoint visible image with respect to the scattering characteristics, and outputs the scattering characteristics subjected to the viewpoint conversion processing to the luminance distribution calculation unit 5. Further, the second viewpoint conversion unit 14 performs viewpoint conversion processing on the reflectance from the camera viewpoint visible image to the human viewpoint visible image, and outputs the reflectance subjected to the viewpoint conversion processing to the brightness estimation unit 6.

  In FIG. 12, the brightness estimating unit 6 estimates the brightness of the indoor space based on the brightness distribution in the visual field area input from the brightness distribution calculating unit 5. The brightness estimation unit 6 calculates the brightness from the brightness distribution with respect to the brightness of each partial area of the human-view visible image or the brightness distribution of the entire human-view visible image. The index indicating brightness includes, for example, average brightness, average illuminance, and sense of brightness. The sense of brightness is an index of brightness that considers the effect of the comparison with the ambient brightness on how people feel, and a known technique is used for estimating the brightness based on the brightness distribution. The brightness estimation unit 6 outputs the estimated brightness to the dimming control unit 7.

  The dimming control unit 7 performs the dimming control of the indoor space based on the brightness calculated by the brightness estimating unit 6 so that an illumination space that a person feels comfortable in the visual field of the person can be obtained. When performing the dimming control, the dimming control unit 7 identifies a lighting fixture to be dimmed among the lighting fixtures installed on the ceiling, the wall, the pillar, etc. of the indoor space. Then, the dimming control unit 7 individually adjusts the illuminance of each of the identified lighting fixtures to perform dimming control.

  In the present embodiment, the human position / orientation detection unit 2a and the visual field region estimation unit 3 estimate the human visual field region. You may input the visual field area of a person.

  In the illumination control system according to the embodiment configured as described above, since the image storage unit 8 that stores the visible image is provided, the scattering characteristic for each partial area is determined by using a plurality of camera viewpoint visible images at different photographing times. It is possible to estimate. For this reason, it is necessary to measure the scattering characteristics for each partial area of the indoor space in advance and store it as a database, or to re-measure the scattering characteristics every time the equipment such as desks and shelves installed in the indoor space is changed. The effect of disappearing is obtained.

  In addition, the scattering characteristic / reflectance estimation unit 19 creates a database of light distributions and luminous flux amounts of the lighting fixtures installed at a plurality of locations in the indoor space, and then instructs the dimming control unit 7 to individually control each lighting fixture. By turning on the light, the intensity of light reflected from each lighting fixture and the target surface is acquired. Then, the scattering characteristic / reflectance estimation unit 19 estimates the angle of incidence and the angle of exit from the target surface from the positional relationship among the lighting fixture, the target surface, and the visible image acquisition unit 1, and the scattering characteristic as shown in FIG. Can be estimated. As a result, it is possible to obtain the effect that it is not necessary to measure the scattering characteristic and the reflectance for each partial area of the space in advance and store them as a database. Furthermore, by estimating the scattering characteristic and the reflectance in a time zone such as midnight when there is no person, it becomes possible to perform the correction efficiently.

  In addition, the illumination control system according to the embodiment has an effect of more accurately detecting the position of a person or the direction of a person using a plurality of visible images.

Fourth Embodiment
FIG. 13 is a block diagram showing the configuration of the illumination control system according to the fourth embodiment for implementing the present invention. Illumination control system 400 according to the present embodiment includes visible image acquisition unit 1, viewpoint changing unit 24, brightness distribution calculation unit 5a, brightness estimation unit 6a, dimming control unit 7, and image storage unit 8. And a reflectance estimation unit 29. The present embodiment is different from the viewpoint conversion unit 4 in that it includes the brightness estimation unit 6a and does not include the person position / orientation detection unit 2a, the visual field region estimation unit 3, and the second viewpoint change unit 24. The third embodiment is different from the third embodiment in that the viewpoint changing unit 24 is used and the reflectance estimating unit 29 is used instead of the scattering characteristic 9.

  First, the configuration of the lighting control system according to the present embodiment will be described. A visible camera (not shown) for taking a visible image of the indoor space is installed at a position where the indoor space can be overlooked, for example, a ceiling, a pillar, or a wall. The visible camera photographs the interior space and outputs the photographed visible image to the visible image acquisition unit 1 together with the photographing time. The visible image acquisition unit 1 sends the acquired camera viewpoint visible image to the viewpoint changing unit 24 and the image storage unit 8 together with the shooting time. The image storage unit 8 stores the camera viewpoint visible image acquired by the visible image acquisition unit 1 and the shooting time of the camera viewpoint visible image. The image storage unit 8 outputs the camera viewpoint visible image at the shooting time designated by the reflectance estimation unit 29 to the reflectance estimation unit 29.

  The viewpoint changing unit 24 inputs the camera viewpoint visible image from the visible image acquiring unit 1 and externally inputs the work area in the camera viewpoint visible image. The viewpoint changing unit 24 extracts a visible image of a region (a region corresponding to d2 in FIG. 3) corresponding to a work region in the externally input camera viewpoint visible image from the camera viewpoint visible image acquired by the visible image acquiring unit 1. To do. This visible image is an image (hereinafter referred to as a work area visible image) obtained by cutting out an image of an area corresponding to the work area in the visual field of a person from the camera viewpoint visible image. The viewpoint changing unit 24 outputs the extracted work area visible image to the brightness distribution calculating unit 5a.

  The brightness distribution calculation unit 5a calculates the brightness distribution in the work area based on the work area visible image input from the viewpoint changing unit 24, and outputs the calculated brightness distribution to the brightness estimation unit 6a.

  The reflectance estimation unit 29 extracts a plurality of camera viewpoint visible images having different photographing times from the camera viewpoint visible images acquired by the visible image acquisition unit 1 and the camera viewpoint visible images stored in the image storage unit 8. The reflectance is estimated for each of a plurality of partial regions forming the camera viewpoint visible image acquired by the visible image acquiring unit 1.

  The brightness estimation unit 6a is based on the brightness distribution in the work area input from the brightness distribution calculation unit 5a and the reflectance of each partial area forming the camera viewpoint visible image input from the reflectance estimation unit 29. , Estimates the brightness of the indoor space, and outputs the estimated brightness to the dimming control unit 7. The dimming control unit 7 controls the dimming of the lighting fixture based on the brightness input from the brightness estimating unit 6a.

  Next, the operation will be described. Among the constituent elements in the present embodiment, the visible image acquisition unit 1, the dimming control unit 7, and the image storage unit 8, which have the same reference numerals as those in the third embodiment, operate in the same manner as in the third embodiment. Therefore, the description is omitted in this embodiment. The viewpoint changing unit 24 in the present embodiment does not perform the viewpoint converting process like the viewpoint converting unit 4 in the third embodiment, but only performs the extracting process of the work area input from the outside.

  The brightness distribution calculation unit 5a in the present embodiment differs from the brightness distribution calculation unit 5 in Embodiment 3 in that the scattering characteristic is not input. Therefore, the brightness distribution calculation unit 5a calculates the brightness distribution from the work area visible image input from the viewpoint changing unit 24 by the same method as the calculation method performed by the brightness distribution calculation unit 5 in the third embodiment. The correction processing of the luminance distribution based on the scattering characteristic is not performed.

  The reflectance estimation unit 29 estimates the reflectance for each partial area in the camera viewpoint visible image, not the scattering characteristic. The reflectance is the light-receiving luminance of the visible camera with respect to the luminance of the light source. The light reception brightness of the visible camera is the brightness of each pixel value of the camera viewpoint visible image acquired by the visible image acquisition unit 1, and is calculated using the same method as the calculation method performed by the brightness distribution calculation unit 5a. On the other hand, the brightness of the light source needs to be measured by separately providing a brightness sensor for measuring the brightness of the light source, and this measured value is used as the brightness of the light source for calculating the reflectance. The calculated reflectance of the camera viewpoint visible image is input to the brightness estimation unit 6a.

The brightness estimation unit 6a estimates the illuminance as brightness from the brightness distribution calculated by the brightness distribution calculation unit 5a and the reflectance estimated by the reflectance estimation unit 29. The reflectance output from the reflectance estimation unit 29 is the reflectance of the entire area of the camera viewpoint visible image, and the luminance distribution input from the luminance distribution calculation unit 5a is of the area corresponding to the work area of the camera viewpoint visible image. Since the images are visible from the camera viewpoint, the target area is different. Therefore, when the illuminance is calculated by the brightness estimation unit 6a, the target areas need to be the same. Therefore, the illuminance is calculated after extracting a region corresponding to the work region from the reflectance distribution of the camera viewpoint visible image output from the reflectance estimation unit 29. The illuminance E can be calculated using equation (2), where ρ is the reflectance and L is the brightness.
E = π / ρ × L (2)

  The illuminance calculated by the brightness estimation unit 6a is input to the dimming control unit 7. The dimming control unit 7 controls the dimming of the luminaire so that the illuminance calculated by the brightness estimating unit 6 has a desired value so that an illumination space that a person feels comfortable in the visual field of the person can be obtained. . When performing the dimming control, the dimming control unit 7 identifies a lighting fixture to be dimmed among the lighting fixtures installed on the ceiling, the wall, the pillar, etc. of the indoor space. Then, the dimming control unit 7 individually adjusts the illuminance of each specified lighting fixture to perform dimming control.

  The work area input to the viewpoint changing unit 24 may be a work area of a person in the room, for example, a work desk area. In this case, the lighting control system according to the present embodiment has an effect that the desk top surface can be set to a desired lighting environment. Regardless of how the brightness of the person in the room is perceived, there is an illuminance standard defined by the JIS standard, and if the average brightness of the brightness estimated from the brightness distribution in the brightness estimating unit 6a is equal to or higher than the illuminance standard. It is possible to provide a lighting control system that keeps the environment.

  The illumination control system according to the embodiment configured as described above includes the image storage unit 8 that stores a visible image, and thus the reflectance for each partial region is estimated using a plurality of camera viewpoint visible images at different shooting times. It becomes possible to do. Therefore, it is necessary to measure the reflectance for each partial area of the indoor space in advance and store it as a database, or to re-measure the reflectance every time the equipment such as a desk or a shelf installed in the indoor space is changed. The effect of disappearing is obtained.

Embodiment 5.
FIG. 14 is a block diagram showing the configuration of the illumination control system according to the fifth embodiment for carrying out the present invention. Illumination control system 500 according to the present embodiment includes visible image acquisition unit 1, person position / orientation detection unit 2a, visual field region estimation unit 3a, viewpoint conversion unit 4, brightness distribution calculation unit 5, and brightness. The estimation unit 6a, the dimming control unit 7, the image storage unit 8, the scattering characteristic / reflectance estimation unit 19, and the partition position estimation unit 10 are provided. The difference from the other example of the third embodiment is that the partition position estimation unit 10 is provided.

  First, the configuration of the lighting control system according to the present embodiment will be described. A visible camera (not shown) for taking a visible image of the indoor space is installed at a position where the indoor space can be overlooked, for example, a ceiling, a pillar, or a wall. The visible camera photographs the interior space and outputs the photographed visible image to the visible image acquisition unit 1 together with the photographing time. The visible image acquisition unit 1 includes a human position / orientation detection unit 2a, a viewpoint conversion unit 4, an image storage unit 8, a scattering characteristic / reflectance estimation unit 19, and a partition position estimation unit 10 together with the captured camera visual point visual image. Output to.

  The image storage unit 8 stores the camera viewpoint visible image acquired by the visible image acquisition unit 1 and the shooting time of the camera viewpoint visible image. The image storage unit 8 outputs the camera viewpoint visible image at the photographing time designated by the person position / orientation detection unit 2 to the person position / orientation detection unit 2a. Further, the image storage unit 8 outputs the camera viewpoint visible image at the photographing time designated by the scattering characteristic / reflectance estimating unit 19 to the scattering characteristic / reflectance estimating unit 19. Further, the image storage unit 8 outputs the camera viewpoint visible image at the shooting time designated by the partition position estimation unit 10 to the partition position estimation unit 10.

  The human position / orientation detection unit 2a determines the position of a person present in the indoor space from the camera viewpoint visible image acquired by the visible image acquisition unit 1 and the camera viewpoint visible image stored in the image storage unit 8. Detects the direction of a person. The camera viewpoint visible image acquired by the visible image acquisition unit 1 and the position and direction of the person who is in the room are output to the visual field region estimation unit 3a.

  The partition position estimation unit 10 extracts a plurality of camera viewpoint visible images having different shooting times from the camera viewpoint visible images acquired by the visible image acquisition unit 1 and the camera viewpoint visible images stored in the image storage unit 8. The position of the partition arranged in the room is estimated based on a plurality of camera viewpoint visible images at different photographing times, and is output to the visual field region estimation unit 3a.

  The visual field region estimation unit 3a estimates the camera viewpoint visible image input from the human position / orientation detection unit 2a, the position and orientation of the person in the camera viewpoint visible image detected by the position / orientation detection unit 2a, and partition position estimation. The visual field area of the person is estimated based on the position of the partition input from the unit 10, and the visual field area in the camera visual point visible image is output to the visual point conversion unit 4.

  The viewpoint conversion unit 4 inputs the camera viewpoint visible image from the visible image acquisition unit 1, and inputs the visual field region of the person who is the occupant from the visual field region estimation unit 3. The viewpoint conversion unit 4 extracts the visible image of the area corresponding to the human visual field from the entire area of the camera visual image, and changes the human visual point from the visual point of the camera installation position to the human visual point. Image conversion is performed by performing viewpoint conversion processing from the camera viewpoint visible image in the area corresponding to the visual field area to the human viewpoint visible image. That is, the viewpoint conversion unit 4 performs image conversion of the camera viewpoint visible image into the human viewpoint visible image in the human visual field. The viewpoint conversion unit 4 outputs the human viewpoint visible image after the image conversion to the brightness distribution calculation unit 5.

  The scattering characteristic / reflectance estimation unit 19 uses the camera viewpoint visible images acquired by the visible image acquisition unit 1 and the camera viewpoint visible images accumulated in the image accumulating unit 8 to obtain a plurality of camera viewpoint visible images having different photographing times. And the scattering characteristic and the reflectance are estimated for each of the plurality of partial regions forming the camera viewpoint visible image acquired by the visible image acquiring unit 1. Then, the second viewpoint conversion unit 14 performs viewpoint conversion processing from the camera viewpoint visible image to the human viewpoint visible image with respect to the scattering characteristics, and outputs the scattering characteristics subjected to the viewpoint conversion processing to the luminance distribution calculation unit 5. Further, the second viewpoint conversion unit 14 performs viewpoint conversion processing on the reflectance from the camera viewpoint visible image to the human viewpoint visible image, and outputs the reflectance subjected to the viewpoint conversion processing to the brightness estimation unit 6a.

  The luminance distribution calculation unit 5 calculates the luminance distribution in the visual field region based on the human viewpoint visible image input from the viewpoint conversion unit 4, and constitutes the human viewpoint visible image input from the second viewpoint conversion unit 14. The brightness distribution in the visual field area is corrected based on the scattering characteristics for each area and the visual point direction for each partial area in the human visual point visible image input from the visual point conversion unit 4. The corrected luminance distribution in the visual field area is output to the brightness estimation unit 6a.

  The brightness estimation unit 6a calculates the space based on the brightness distribution in the visual field region input from the brightness distribution calculation unit 5 and the reflectance of each partial region in the human-view visible image input from the second viewpoint conversion unit 14. Brightness is estimated, and the estimated brightness is output to the dimming control unit 7. The dimming control unit 7 controls the dimming of the lighting fixture based on the brightness input from the brightness estimating unit 6a.

  Note that, unlike the illumination control system 510 shown in FIG. 15, even if the brightness distribution in the visual field calculated by the brightness distribution calculation unit 5 is output to the dimming control unit 7 without using the brightness estimation unit 6a. Good. In this case, the dimming control unit 7 controls the dimming of the luminaire based on the brightness distribution input from the brightness distribution calculating unit 5.

  Next, the operation will be described. FIG. 16 is a flowchart illustrating an operation of the lighting control system according to the fifth embodiment of the present invention. First, a visible image of the current camera viewpoint is captured by the visible camera. The visible image acquisition unit 1 acquires a camera viewpoint visible image captured by a visible camera. The current visible image of the camera viewpoint is input from the visible image acquisition unit 1 to the partition position estimation unit 10 (step S11). The partition position estimation unit 10 performs the processing from step S12 to step S15.

  An edge of each image is extracted using the current camera viewpoint visible image and the camera viewpoint visible image at the same time on another day (step S12). Next, it is determined whether or not the position of the partition has been changed (step S13). When the difference value between the edges of the two images exceeds a predetermined threshold value, it is determined that the object photographed by the visible camera has moved significantly, that is, the layout of the indoor space has been changed and the position of the partition has been changed. It proceeds to step S14. On the other hand, when the edge difference value is less than or equal to the predetermined threshold value, it is determined that the partition position has not been changed, and the process proceeds to step S16.

  The position of the partition in the camera viewpoint visible image is estimated (step S14). The method of estimating the position of the partition will be described later. The position of the partition estimated in step S14 is saved (step S15), and the process proceeds to step S16.

  The scattering characteristic / reflectance estimation unit 19 performs the processing from step S16 to step S19. The difference between the current camera viewpoint visible image and the camera viewpoint visible image for each partial area captured in another time zone on the same day is calculated (step S16). Then, it is determined whether or not there is a change in the scattering characteristic and the reflectance by looking at the tendency of the difference between the camera viewpoint visible images for each partial area calculated in step S16 (step S17). When the difference is extremely large only in the specific region, the process proceeds to step S18, it is estimated that the scattering characteristic and the reflectance are changed (step S18), and the estimated scattering characteristic and the reflectance are stored (step S19). . If it is determined in step S17 that there is no change in the scattering characteristic and the reflectance, the process proceeds to step S20. Note that the change in the scattering characteristic and the reflectance is determined using the difference value of the camera visible image. Although described, the determination may be performed using the edge difference value as in step S13.

  The person position / orientation detecting unit 2a detects the person's position and the person's orientation from the camera viewpoint visible image at the current time and the camera viewpoint visible image several minutes or tens of minutes ago (step S20). The visual field estimation unit 3a estimates the visual field of a person (step S21). If the position of the partition is within the visual field of the person, the visual field is corrected according to the height of the partition. For example, if the partition is estimated to be higher than the person's line of sight, the other side of the partition is not visible to the person, and the other side of the person's visual field across the partition is the person's visual field. Exclude from. Even if the partition is lower than the person's line of sight, the area on the opposite side of the person's position across the partition in the human visual field may look different between the camera viewpoint and the human viewpoint. A credibility index may be newly provided and credibility of the same area may be set according to the height of the partition.

  The viewpoint conversion unit 4 extracts the visible image of the area corresponding to the human visual field from the entire area of the camera visual image, and changes the human visual point from the visual point of the camera installation position to the human visual point. Viewpoint conversion processing is performed from the camera viewpoint visible image in the area corresponding to the visual field area to the human viewpoint visible image to perform image conversion (step S22). The brightness distribution calculation unit 5 calculates the brightness distribution in the visual field based on the human-view visible image and the scattering characteristics (step S23). The brightness estimation unit 6a estimates the brightness based on the brightness distribution and the reflectance within the visual field area (step S24). The reflectance is used when calculating the illuminance as the brightness. The dimming control unit 7 identifies the lighting fixture to be dimmed (step S25), and finally controls the dimming of the lighting fixture (step S26).

  FIG. 17 is an explanatory diagram illustrating an operation of the partition position estimation unit 10 in the lighting control system according to the fifth embodiment of the present invention. A partition position detection method will be described with reference to (a1) and (a2) of FIG. 17 (a1) and (a2) show how the same partition is irradiated with light from different angles. If there is a partition, a shadow will appear around the partition depending on the position of the light source. In the visible image captured by the visible camera, the shadow is projected with lower brightness than the surroundings, and the direction of the shadow changes depending on the position of the light source. This is used to estimate the position of the partition.

  Further, a partition height estimation method will be described with reference to (b1) and (b2) of FIG. (B1) and (b2) of FIG. 17 show a state in which the partitions having different heights are irradiated with light from the same direction. After estimating the position of the partition, we focus on one visible image and estimate the height of the partition from the ratio of shadow lengths. The target for which the partition position estimation unit 10 estimates the position is not limited to the partition, and may be any object such as a shelf or a display as long as it blocks the view of a person.

  If there is no change in the layout of the space taken by the visible camera, the position of the partition does not change. For this reason, the partition position estimation unit 10 estimates the partition positions of the entire area of the camera viewpoint visible image once, and accumulates the partition positions, and the partition position is estimated every time the camera viewpoint image is input from the visible image acquisition unit 1. Need not be estimated.

  In the lighting control system according to the embodiment configured as described above, the illuminance environment changes due to the influence of weather, lighting equipment, and layout, but the position of the partition is changed using the brightness change for each partial area from a plurality of visible images. Can be estimated and the human visual field can be estimated more accurately, so that an area that is not the human visual field can be specified, and the effect of turning off unnecessary illumination can be obtained.

1 visible image acquisition unit, 2, 2a human position / orientation detection unit, 3, 3a visual field region estimation unit, 4 viewpoint conversion unit, 5, 5a luminance distribution calculation unit, 6, 6a brightness estimation unit, 7 dimming control unit , 8 image storage unit, 9 scattering characteristic estimating unit, 10 partition position estimating unit, 14 second viewpoint converting unit, 19 scattering characteristic / reflectance estimating unit, 24 viewpoint changing unit, 29 reflectance estimating unit, 100, 110, 200 , 210, 300, 310, 400, 500, 510 Lighting control system.

An illumination control system according to the present invention is input with a visible image acquisition unit that acquires a visible image and a visual field of a person, and converts the visible image acquired by the visible image acquisition unit into a visible image of a human viewpoint in the visual field. A viewpoint conversion unit, a brightness distribution calculation unit that calculates a brightness distribution of a visual field region based on a visible image of a human viewpoint, a dimming control unit that controls dimming of a lighting device based on the brightness distribution ,
An image storage unit that stores the visible image acquired by the visible image acquisition unit together with the shooting time .

Claims (13)

A visible image acquisition unit that acquires a visible image,
A visual field region of a person is input, and a viewpoint conversion unit that converts the visible image acquired by the visible image acquisition unit into a visible image of a human viewpoint in the visual field region,
A luminance distribution calculation unit that calculates the luminance distribution of the visual field region based on the visible image of the human viewpoint;
An illumination control system comprising: a dimming control unit that controls dimming of a lighting fixture based on the brightness distribution. A brightness estimation unit that estimates the brightness of the visual field region based on the brightness distribution,
The lighting control system according to claim 1, wherein the dimming control unit controls dimming of the lighting fixture based on the brightness of the visual field region estimated based on the luminance distribution. An image storage unit that stores the visible image acquired by the visible image acquisition unit together with a shooting time,
A plurality of visible images having different photographing times are extracted from the visible images acquired by the visible image acquisition unit and the visible images accumulated in the image accumulating unit, and the visible images having different photographing times are extracted. A scattering characteristic / reflectance estimating unit for estimating a scattering characteristic and a reflectance for each of a plurality of partial regions forming the visible image acquired by the visible image acquiring unit based on an image,
The brightness distribution calculation unit corrects the brightness distribution based on the scattering characteristic,
The illumination control system according to claim 2, wherein the brightness estimation unit estimates the brightness of the visual field region based on the corrected luminance distribution and the reflectance. An image storage unit that stores the visible image acquired by the visible image acquisition unit together with a shooting time,
A plurality of visible images having different photographing times are extracted from the visible images acquired by the visible image acquisition unit and the visible images accumulated in the image accumulating unit, and the visible images having different photographing times are extracted. A visible light image acquisition unit based on an image and a scattering characteristic estimating unit for estimating a scattering characteristic for each of a plurality of partial regions constituting the visible image,
The illumination control system according to claim 1, wherein the brightness distribution calculation unit corrects the brightness distribution based on the scattering characteristic. The visible image acquired by the visible image acquisition unit is input, and a human position / orientation detection unit that detects a position of a person and a direction of the person from the visible image,
A human visual field estimation unit that estimates the visual field based on the human position and the human orientation detected by the human position / orientation detection unit, and outputs the visual field region to the visual point conversion unit. The lighting control system according to claim 1, wherein the lighting control system is a lighting control system. A brightness estimation unit that estimates the brightness of the visual field region based on the brightness distribution,
The illumination control system according to claim 5, wherein the dimming control unit controls dimming of the lighting fixture based on the brightness of the visual field region estimated based on the brightness distribution. An image storage unit that stores the visible image acquired by the visible image acquisition unit together with a shooting time,
A plurality of the visible images with different photographing times are extracted from the visible images acquired by the visible image acquisition unit and the visible images accumulated in the image accumulating unit, and the visible images with different photographing times are extracted. A scattering characteristic / reflectance estimating unit for estimating a scattering characteristic and a reflectance for each of a plurality of partial regions forming the visible image acquired by the visible image acquiring unit based on an image,
The brightness distribution calculation unit corrects the brightness distribution based on the scattering characteristic,
The illumination control system according to claim 6, wherein the brightness estimating unit estimates the brightness of the visual field region based on the corrected luminance distribution and the reflectance. An image storage unit that stores the visible image acquired by the visible image acquisition unit together with a shooting time,
A plurality of visible images having different photographing times are extracted from the visible images acquired by the visible image acquisition unit and the visible images accumulated in the image accumulating unit, and the visible images having different photographing times are extracted. A visible light image acquisition unit based on an image and a scattering characteristic estimating unit for estimating a scattering characteristic for each of a plurality of partial regions constituting the visible image,
The illumination control system according to claim 5, wherein the brightness distribution calculation unit corrects the brightness distribution based on the scattering characteristic. An image storage unit that stores the visible image acquired by the visible image acquisition unit together with a shooting time,
A plurality of visible images having different photographing times are extracted from the visible images acquired by the visible image acquisition unit and the visible images accumulated in the image accumulating unit, and the visible images having different photographing times are extracted. A scattering characteristic estimation unit that estimates the scattering characteristic for each of a plurality of partial regions forming the visible image acquired by the visible image acquisition unit based on an image,
A partition position estimation unit that estimates the position of a partition arranged in the room based on the plurality of visible images with different shooting times,
The visual field region estimation unit estimates the visual field region based on the position of the person, the direction of the person, and the position of the partition, and outputs the visual field region to the viewpoint conversion unit,
The illumination control system according to claim 5, wherein the brightness distribution calculation unit corrects the brightness distribution based on the scattering characteristic. An image storage unit that stores the visible image acquired by the visible image acquisition unit together with a shooting time,
A plurality of visible images having different photographing times are extracted from the visible images acquired by the visible image acquisition unit and the visible images accumulated in the image accumulating unit, and the visible images having different photographing times are extracted. A scattering characteristic / reflectance estimating unit that estimates a scattering characteristic and a reflectance for each of a plurality of partial regions forming the visible image acquired by the visible image acquiring unit based on an image,
A partition position estimation unit that estimates the position of the partition arranged in the room based on the plurality of visible images with different shooting times;
And a brightness estimation unit that estimates the brightness of the visual field region based on the brightness distribution,
The visual field region estimation unit estimates the visual field region based on the position of the person, the direction of the person, and the position of the partition, and outputs the visual field region to the viewpoint conversion unit,
The brightness distribution calculation unit corrects the brightness distribution based on the scattering characteristic,
The illumination control system according to claim 5, wherein the brightness estimating unit estimates the brightness of the visual field region based on the corrected luminance distribution and the reflectance.   The human position / orientation detection unit extracts a plurality of the visible images with different shooting times from the visible images acquired by the visible image acquisition unit and the visible images stored in the image storage unit, 11. The illumination control system according to claim 7, wherein the position and the direction of the person are detected based on the plurality of visible images at different photographing times. A visible image acquisition unit that acquires a visible image,
A work area is input, and a viewpoint changing unit that extracts a visible image of a region corresponding to the working region from the visible image acquired by the visible image acquiring unit,
A brightness distribution calculating unit that calculates a brightness distribution of the work area based on a visible image of an area corresponding to the work area;
An image storage unit that stores the visible image acquired by the visible image acquisition unit together with a shooting time,
A plurality of the visible images with different photographing times are extracted from the visible images acquired by the visible image acquisition unit and the visible images accumulated in the image accumulating unit, and the visible images with different photographing times are extracted. A reflectance estimation unit that estimates the reflectance for each of a plurality of partial regions forming the visible image acquired by the visible image acquisition unit based on an image,
A brightness estimation unit that estimates the brightness of the work area based on the brightness distribution and the reflectance of the work area calculated by the brightness distribution calculation unit,
An illumination control system, comprising: a dimming control unit that controls dimming of a lighting fixture based on the brightness of the work area. A visible image acquisition step of acquiring a visible image,
A viewpoint conversion step of inputting a visual field of a person and converting the visible image acquired in the visible image acquisition step into a visible image of a human viewpoint in the visual area,
A luminance distribution calculating step of calculating a luminance distribution of the visual field region based on the visible image of the human viewpoint;
A dimming control step of controlling dimming of a lighting fixture based on the brightness distribution.

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