JP2011091641A - Monitor camera system, monitor camera, optical environment adjuster and optical environment adjustment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a monitor camera system which reliably estimates the current optical environment, actively improves an optical environment that is generated by external conditions corresponding to the estimation result and properly acquires captured image data, a monitor camera, an optical environment adjuster and an optical environment adjustment method. <P>SOLUTION: A light irradiation state estimation part 120 estimates a state of light irradiated on a main object 30 in a field of view 10 of the monitor camera 110. Based on the irradiation state estimation data, an optical environment adjustment part 130 that is arranged outside the monitor camera 110 adjusts either or both of natural lighting and artificial lighting to the main object 30 within the field of view 10. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to, for example, a monitoring camera system, a monitoring camera, a light environment adjustment device, and a light environment adjustment method suitable for performing authentication of a person in an imaging field of view. The present invention relates to a monitoring camera system, a monitoring camera, a light environment adjusting device, and a light environment adjusting method capable of ensuring a good light environment capable of performing accurate photographing.

  In recent years, a technique for performing face authentication based on a photographed image obtained by a surveillance camera is becoming widespread at an entrance of a building or the like. In general, the face authentication described above is often performed by applying template matching as an image recognition technique to a captured image.

  Since template matching is executed based on a comparison process between a registered reference image and an image acquired by photographing, it is necessary to register a reference image in advance. This registration is performed by photographing a face of each subject person for registration processing of a reference image related to the surveillance subject person and storing face image data obtained by the photography in a predetermined database. Therefore, when there are many monitoring subjects, the burden of the worker who performs this registration work becomes large.

  There has already been proposed a technique for reducing the burden associated with face image registration work as described above, which is a preparatory work for performing face authentication (see, for example, Patent Document 1).

  In Patent Literature 1, when an image is acquired by a monitoring camera, if it is identified that the image is specific image data including a human face, the image data is stored, and the storage is performed. A technique for facilitating face image registration setting work by enabling a registration manager to search and perform registration processing on the image data at an arbitrary time zone is disclosed.

  On the other hand, in order to properly acquire an image with the surveillance camera, it is necessary to ensure a certain light environment such as avoiding backlighting. As described above, a technique for satisfying the requirements related to the light environment at the time of image data acquisition has already been proposed (see, for example, Patent Document 2).

  In Patent Document 2, a general forward / backlight identification device that identifies forward / backlight based only on the current date and time and the direction of the surveillance camera provides a practical response to the important condition of the installation location of the surveillance camera. Focusing on the problem that could not be taken, a technique has been disclosed in which it is possible to accurately identify whether or not backlighting occurs in consideration of point information indicating a point where a surveillance camera is installed.

JP 2000-339466 A (refer to claim 2, paragraphs 0002 to 0005) JP 2005-354746 A (refer to claim 1, paragraph 0006, paragraph 0012, etc.)

  When face authentication is performed using image data acquired by a surveillance camera, if the technique proposed in Patent Document 1 is adopted, there is a possibility that the burden related to photographing and registration of the faces of individual subjects accumulated in the database may be reduced. . However, the reduction in the burden of preparation work related to face authentication does not directly lead to improvement of shooting conditions including the light environment in shooting and accuracy of image recognition.

  On the other hand, if the technique proposed in Patent Document 2 is adopted, there is a possibility that the identification accuracy as to whether or not the subject is not backlit during photographing can be improved. However, if the light environment related to shooting is poor, such as when the light distribution on the face of the person being photographed is actually backlit, it is not a technology that improves the light environment itself. However, there is a risk that face authentication cannot be performed because a clear image that can be used for image recognition processing cannot be obtained.

  In other words, the techniques described in Patent Document 1 and Patent Document 2 accept the light environment itself caused by external conditions, so that the burden of preparation work related to face authentication is reduced and the subject is not backlit. Whether or not the identification accuracy is improved.

  The present invention has been made in view of the situation as described above, and accurately estimates the light environment at the present time point, and also with respect to the light environment itself generated by external conditions according to the estimation result. It is an object of the present invention to provide a monitoring camera system, a monitoring camera, a light environment adjusting device, and a light environment adjusting method capable of actively improving and acquiring captured image data accurately.

In order to solve the above-mentioned problems, the following technologies are proposed here.
(1) a surveillance camera installed so as to include a predetermined surveillance area in the imaging field;
A light irradiation state estimation unit for estimating a light irradiation state with respect to a main subject in the imaging field of view of the monitoring camera and obtaining light irradiation state estimation data representing the estimation result;
Light environment adjustment installed outside the monitoring camera to adjust either or both of the lighting and illumination of the main subject in the imaging field based on the light irradiation state estimation data by the light irradiation state estimation unit And
A surveillance camera system comprising:
In the surveillance camera system of (1), the surveillance camera is installed so as to include a predetermined surveillance area in its imaging field of view. Further, the light irradiation state estimation unit estimates the light irradiation state with respect to the main subject in the imaging field of view of the monitoring camera and obtains light irradiation state estimation data representing the estimation result. Further, the light environment adjusting unit installed outside the surveillance camera is either or both of lighting and illumination of the main subject in the imaging field of view based on the light irradiation state estimation data by the light irradiation state estimation unit Adjust.
(2) The light irradiation state estimation unit is based on an imaging output by the monitoring camera with respect to a reflecting surface having a known reflectance having one or more colors excluding black of a member arranged in an imaging field of view of the monitoring camera. The surveillance camera system according to (1), wherein the state of light irradiation on the main subject is estimated.

In the monitoring camera system of (2) above, particularly in the monitoring camera system of (1), the light irradiation state estimation unit is configured to irradiate the main subject with light based on the imaging output of the monitoring camera on a specific reflecting surface. Is estimated. The specific reflecting surface is a surface of a member arranged in the imaging field of view of the monitoring camera, and the surface is a reflecting surface having a known reflectance having one or more colors except black.
(3) The monitoring camera according to (2), wherein the light irradiation state estimation unit estimates a light irradiation state with respect to the main subject based on an imaging output by the monitoring camera with respect to the plurality of separated reflecting surfaces. system.

In the monitoring camera system of (3), a plurality of spaced apart reflection surfaces are used particularly in the monitoring camera system of (2). And the said light irradiation condition estimation part estimates the light irradiation condition with respect to the said main subject based on the imaging output by the said monitoring camera with respect to these reflective surfaces.
(4) The light irradiation state estimation unit estimates a light irradiation state with respect to the main subject based on an imaging output of the monitoring camera with respect to the reflection surface having a plurality of divided regions whose brightness changes stepwise. (2) The surveillance camera system characterized by the above-mentioned.

In the surveillance camera system of (4), in particular, in the surveillance camera system of (2), the reflection surface having a plurality of divided regions whose brightness changes stepwise is used. And the said light irradiation condition estimation part estimates the irradiation condition of the light with respect to the said main subject based on the imaging output by the said monitoring camera with respect to such a specific reflective surface.
(5) The light irradiation state estimation unit determines whether or not the light irradiation state with respect to the main subject is appropriate based on a comparison of a plurality of imaging outputs from the monitoring camera with respect to the plurality of separated reflecting surfaces. (3) The surveillance camera system.

In the monitoring camera system of (5) above, in particular, in the monitoring camera system of (2), the light irradiation state estimation unit is based on the comparison of the plurality of imaging outputs from the monitoring camera with respect to the plurality of separated reflecting surfaces. The suitability of the light irradiation state on the subject is determined.
(6) The light environment adjustment unit includes a light transmission state variable member that adjusts the daylighting by adjusting the transmission state of external light in response to the light irradiation state estimation data by the light irradiation state estimation unit. The surveillance camera system according to (1), which is characterized.

In the monitoring camera system of (6) above, particularly in the monitoring camera system of (1), the light environment adjusting unit responds to the light irradiation state estimation data by the light irradiation state estimation unit by the light transmission state variable member. The lighting is adjusted by adjusting the transmission state of the outside light.
(7) The light transmission state variable member includes any one of a blind, a roll screen, a curtain, an electro-optical light transmission variable variable laminate, and an LED transparent variable screen (6). Surveillance camera system.

In the surveillance camera system of (7), particularly in the surveillance camera system of (6), as the light transmission state variable member, a blind, a roll screen, a curtain, an electro-optical light transmission characteristic variable laminate, an LED transmission property The external light transmission state is adjusted using one of the variable screens.
(8) The light environment adjusting unit includes a light amount adjusting unit that adjusts the amount of illumination light applied to the main subject in response to the light irradiation state estimation data from the light irradiation state estimating unit (1). ) Surveillance camera system.

In the surveillance camera system of (8), particularly in the surveillance camera system of (1), the light environment adjustment unit is responsive to the light irradiation state estimation data by the light irradiation state estimation unit by the light amount adjustment unit. Adjust the amount of illumination light applied to the main subject.
(9) The surveillance camera system according to (8), wherein the light amount adjustment unit includes a supply power control circuit that controls supply power to the light source of the illumination light.

In the monitoring camera system of (9) above, in particular, in the monitoring camera system of (8), the light amount adjusting unit irradiates illumination light by controlling the supply power of the illumination light to the light source by the supply power control circuit. Adjust the amount.
(10) a light irradiation state estimation data calculation unit for calculating light irradiation state estimation data corresponding to the light irradiation state to the main subject in the imaging field;
The light irradiation state estimation data calculated by the light irradiation state estimation data calculation unit is installed outside so as to adjust either or both of lighting and illumination on the main subject based on the light irradiation state estimation data. A light irradiation state estimation data supply unit to be supplied to the light environment control device;
A surveillance camera comprising:

In the monitoring camera of the above (10), the light irradiation state estimation data calculation unit calculates light irradiation state estimation data corresponding to the light irradiation state to the main subject in the imaging field of view. Then, the light irradiation state estimation data supply unit calculates the light irradiation state estimation data calculated by the light irradiation state estimation data calculation unit based on the light irradiation state estimation data. Or it supplies to the light environment adjustment apparatus installed outside so that both may be adjusted.
(11) a light irradiation state estimation data receiving unit for receiving the light irradiation state estimation data from a monitoring camera that supplies light irradiation state estimation data corresponding to the light irradiation state to the main subject in the imaging field;
A light environment adjusting unit that adjusts either or both of lighting and illumination on the main subject based on the light irradiation state estimation data received by the light irradiation state estimation data receiving unit;
A light environment adjusting device comprising:

The light environment adjustment device according to (11) has a light irradiation state estimation data receiving unit that receives light irradiation state estimation data corresponding to the light irradiation state to the main subject in the imaging field from a monitoring camera that supplies the light to the outside. The light irradiation state estimation data is received. Then, the light environment adjusting unit adjusts either or both of the lighting and illumination of the main subject based on the light irradiation state estimation data received by the light irradiation state estimation data receiving unit.
(12) a light irradiation state estimation data calculating step for calculating light irradiation state estimation data representing the light irradiation state with respect to the main subject in the imaging field of the surveillance camera;
A light environment adjustment step of adjusting either or both of the lighting and illumination of the main subject in the imaging field based on the light irradiation state estimation data calculated in the light irradiation state estimation data calculation step;
A light environment adjusting method characterized by comprising:

  In the light environment adjustment method of (12) above, in the light irradiation state estimation data calculation step, light irradiation state estimation data representing the light irradiation state with respect to the main subject in the imaging field of view of the monitoring camera is calculated. Further, in the light environment adjustment step, either or both of lighting and / or illumination of the main subject in the imaging field of view is adjusted based on the light irradiation state estimation data calculated in the light irradiation state estimation data calculation step. To do.

  The present invention accurately estimates the light environment at the present time point, and actively improves the light environment itself caused by external conditions according to the estimation result, thereby accurately capturing the captured image data. Camera system, surveillance camera, light environment adjustment device, and light environment adjustment method can be implemented.

It is a conceptual diagram showing the surveillance camera system which is one embodiment of this invention. It is a conceptual diagram of the optical environment regarding imaging | photography in the case of performing face authentication using a surveillance camera. It is a conceptual diagram showing the state seen from the viewpoint which sees the light environment of FIG. 2 from the front side of the main subject. It is a figure which illustrates the aspect of the reflecting plate applied to the surveillance camera system of FIG. 1 and FIG. It is a conceptual diagram showing the condition which determines the suitability of the light irradiation condition with respect to a main subject based on the imaging output by the monitoring camera with respect to two separated reflective surfaces when sunlight is a follow light. It is a conceptual diagram showing the condition which judges the suitability of the light irradiation condition with respect to a main subject based on the imaging output by the surveillance camera with respect to two separated reflective surfaces when sunlight is backlight. FIG. 7 is a diagram illustrating a determination criterion in the case of determining the suitability (forward light and backlight) of the light irradiation state on the main subject based on the imaging output. It is a block diagram showing one embodiment of the surveillance camera and light environment control device of the present invention. It is a flowchart showing operation | movement of the light environment adjusting device in the surveillance camera system which is other one Embodiment of this invention. It is a flowchart showing operation | movement of the light environment adjustment apparatus in the surveillance camera system which is another one Embodiment of this invention. It is a flowchart showing operation | movement of the light environment adjustment apparatus in the surveillance camera system which is another one Embodiment of this invention. It is a conceptual diagram showing the surveillance camera system which is other one Embodiment of this invention. It is a flowchart showing operation | movement of the light environment adjustment apparatus in the surveillance camera system of FIG. It is a figure used for description of the illuminance calculation method for face authentication applicable to the embodiment of the present invention. It is a figure used for description of the basic concept of the arrangement | positioning of a reflecting plate applied to embodiment of this invention, and the illumination intensity calculation method. It is a figure used for description of the illumination intensity detection method on the conditions in which external light injects from one direction in embodiment of this invention. It is a figure used for description of the illumination intensity detection method on the conditions in which external light injects from another one direction in embodiment of this invention. It is a figure used for description of the illumination intensity detection method on the conditions in which external light injects from another one direction in embodiment of this invention. It is a figure used for description of the illuminance detection method on the conditions where the incident direction of external light changes in the embodiment of the present invention. It is a figure used for description of the simple illumination intensity calculation method applicable to embodiment of this invention.

  Hereinafter, the present invention will be clarified by describing embodiments of the present invention in detail with reference to the drawings.

  FIG. 1 is a conceptual diagram showing a surveillance camera system according to an embodiment of the present invention.

  In the monitoring camera system 100 of FIG. 1, the monitoring camera 110 is installed so as to include a predetermined monitoring area 20 in its imaging field of view 10. This installation takes the form of fixedly or semi-fixedly attached to an appropriate place on the ceiling surface so as to secure a field of view for monitoring visitors to the entrance of the building, for example. In this embodiment, the monitoring area 20 is set equal to the imaging field of view 10.

  Further, a light irradiation state estimation unit 120 is provided that estimates the light irradiation state of the main subject 30 in the imaging field of view 10 of the monitoring camera 110 by a predetermined calculation and obtains light irradiation state estimation data representing the estimation result. Yes.

  A reflective member (reflective plate) 121 is installed at an appropriate place (here, the floor surface 11) in the monitoring area 20 so that the reflective surface 121a whose reflectance is known is the upper surface. As the color of the reflecting surface 121a, one or a plurality of colors other than black are selected. Based on the video signal corresponding to the reflecting surface 121a output from the monitoring camera 110, the light irradiation state estimation unit 120 determines whether or not the main subject 30 exists in the monitoring area 20 at the current time point, Regardless of the state of the surface or the wall surface, the assumed light irradiation state on the main subject 30 is estimated by a predetermined calculation.

  In the monitoring camera system 100 of FIG. 1, the light irradiation state estimation unit 120 is provided independently of the monitoring camera 110 and is configured to be supplied with a video signal from the monitoring camera 110. . However, the light irradiation state estimation unit 120, which is one element in the surveillance camera system of the present invention, may take a form in which this is provided in the surveillance camera 110 as one functional unit that functions similarly. This point will be further described later.

  The main subject 30 is typically a person (particularly the portion of the face 30f). However, as the idea of the present invention, the main subject 30 is another animal, a robot, a vehicle, or the like, as well as biological information and a character string pattern. A thing including can also be a monitoring object.

  On the other hand, a light environment adjustment unit 130 that adjusts the lighting or illumination of the main subject 30 in the imaging visual field 10 based on the light irradiation state estimation data by the light irradiation state estimation unit 120 is installed outside the monitoring camera 110. .

  As will be described in detail later, the light environment adjusting unit 130 is configured to adjust the lighting on the main subject 30 by driving a light transmission state variable member such as a blind or a roll screen with a servo mechanism or the like. It can take a form. Moreover, the form of the light control apparatus 132 which adjusts the electric power supplied to the incandescent lamp and LED which are artificial light sources, and adjusts the light quantity of the illumination light to the main to-be-photographed object 30 can be taken. In the example of FIG. 1, the light environment adjustment unit 130 takes a form including both the light adjustment device 131 and the light adjustment device 132 as described above.

  FIG. 2 is a conceptual diagram of an optical environment related to photographing when face authentication is performed using a surveillance camera.

  FIG. 3 is a conceptual diagram showing a state in which the light environment of FIG. 2 is viewed from the viewpoint of viewing from the front side of the main subject.

  2 and 3, it is assumed that the surveillance camera system of the present invention is installed indoors like an entrance space. When the person 30 as the main subject enters the monitoring area 20, the monitoring area 20 is in the imaging field of view 10 of the monitoring camera 110, so that the person 30 is recorded by the monitoring camera 110 that is always operating.

  On the other hand, a blind 210 that adjusts the daylighting to the main subject 30 is provided in the vicinity of the window glass 2110 so as to appropriately suppress and adjust the incidence of external light (sunlight) LS. The blind 210 is configured such that the angle of the slat 211 can be adjusted by, for example, a servo mechanism that operates in response to light irradiation state estimation data from the light irradiation state estimation unit 120 of FIG.

  The incident direction of the sunlight LS changes according to the season and time, as depicted by a broken line, a solid line, and an alternate long and short dash line in FIG. In the case of FIG. 2, the incident direction indicated by the alternate long and short dash line and the solid line is forward light with respect to the photographing of the person 30, and the incident direction of the broken line is backlight. In one aspect of the present system, outside light (sunlight) LS is appropriately taken in or blocked by adjusting the angle of the slat 211 in accordance with such an incident direction. The blind 210 shown in FIG. 3 is a horizontal blind, but even in the case of a vertical blind, it has the angle of the slat 211, and the incident directions drawn by broken lines, solid lines, and alternate long and short dash lines in FIG. .

  In addition, in the case of this example, a plurality of reflecting plates 220 having a known reflectance on the reflecting surface such as a single one illustrated with reference to FIG. 221, 222, 223).

  As described above with reference to FIG. 1, the light irradiation state estimation unit 120 determines that the person 30 is currently present based on the video signals corresponding to the reflecting surfaces 221, 222, and 223 output from the monitoring camera 110. Irrespective of whether or not it exists in the monitoring region 20 and regardless of the situation of the floor surface or wall surface, the light irradiation state on the person 30 is estimated by a predetermined calculation.

  On the other hand, in the case of FIG. 2 and FIG. 3, a plurality of spot illumination devices 230 (231, 232, 233) are provided on the ceiling, and illumination to the area including the monitoring area 20 is secured by illumination light LB by them. It is configured.

  The light amounts of these spot illumination devices 231, 232, and 233 are configured to be adjustable by, for example, a light control device that operates in response to light irradiation state estimation data from the light irradiation state estimation unit 120 of FIG.

  In one embodiment, which will be described later, an electro-optic light transmission variable variable laminate or LED light transmission variable screen is applied as the window glass 2110, and the light transmission to the main subject is adjusted by adjusting the light transmission characteristic.

  FIG. 4 is a diagram illustrating an example of a reflection plate applied to the surveillance camera system of FIGS. 1 and 2.

  The reflector 410 in FIG. 4A has a reflective surface having the same hue and different brightness in the first region 411, the second region 412, the third region 413, and the fourth region 414. All the reflectivities in the first region 411 to the fourth region 414 are known.

  The reflector 420 in FIG. 4B has a reflective surface of the same hue with different brightness in the first region 421, the second region 422, and the third region 423. The reflectivities in the first region 421 to the region 423 are all known.

  The reflector 430 in FIG. 4C has a reflective surface of the same hue with different brightness in the first region 431 and the second region 432. The reflectivities of the first region 43 and the second region 432 are both known.

  The reflecting plate 440 in FIG. 4D is an example in which a guide display plate indicating an entrance is used as a reflecting plate. As will be further described later with reference to FIG. 20, a minute area in units of pixels that is a part of a character pattern (“Enter” in the drawing) having a known guide display or other reflectance can be used as a reflector. it can.

  With respect to the reflective surface having a plurality of regions with different brightness, such as the reflectors 410, 420, and 430, based on each level of the imaging output signal by the monitoring camera 110 corresponding to each region and the comparison thereof, as described above. The light irradiation state estimation data is calculated by the light irradiation state estimation unit.

  Next, with reference to FIG. 5 to FIG. 6, a technique for determining the suitability of the light irradiation state on the main subject based on the comparison of the plurality of imaging outputs from the surveillance camera with respect to the plurality of separated reflecting surfaces will be described.

  FIG. 5 is a conceptual diagram illustrating a situation in which the suitability of the light irradiation state with respect to the main subject is determined based on the imaging output by the monitoring camera with respect to the two separated reflective surfaces when sunlight is the direct light.

  FIG. 6 is a conceptual diagram illustrating a situation in which the suitability of the light irradiation state on the main subject is determined based on the imaging output by the monitoring camera with respect to two separated reflecting surfaces when sunlight is backlit.

  FIG. 7 illustrates a criterion for determining the suitability of the light irradiation state on the main subject based on the imaging output in FIGS. 5 and 6.

  5 and 6, corresponding parts are denoted by the same reference numerals. Two reflecting surfaces 41 and 42 are set on the floor surface 11 in the monitoring region 20 in the imaging field 10 of the monitoring camera 110. The imaging output (luminance level) of the reflection surfaces 41 and 42 by the monitoring camera 110 is schematically shown by arrows E1 and E2 as shown in the figure.

  When the person 30 as the main subject enters the monitoring area 20, the monitoring area 20 is in the imaging field of view 10 of the monitoring camera 110, so that the person 30 is recorded by the monitoring camera 110 that is always operating.

  The natural light (sunlight) LS1 in FIG. 5 is assumed to be forward light as described above, and the natural light (sunlight) LS2 in FIG. 6 is assumed to be backlight as described above.

  The luminance of the reflecting surfaces 41 and 42 qualitatively tends to show a higher value as the incident angle of natural light (sunlight) is smaller.

  With respect to this phenomenon, in accordance with the specifications of the monitoring camera actually used and the specifications of the reflecting surface, measurement corresponding to the light irradiation state on the main subject is executed in advance. Then, based on this measurement result, a criterion for determining the suitability of the light irradiation state on the main subject is set.

  By the way, although the monitoring target by the monitoring camera 110 is the person 30 that has entered the monitoring area 20, the face 30f of the person 30 is a part where it is desired to obtain a clear image as an imaging target for performing face authentication.

  Therefore, it is desired to secure an appropriate light environment when the face 30f is an imaging target. And it is also the main purpose in the embodiment of the present invention to prepare such a light environment in advance so as to cope with an unexpected intruder.

  However, with respect to the position of the face 30f, which is an aerial position that is separated from the floor 11 by about the height of the person, it is difficult to carry out photometry for ensuring the light environment at the time when the photometric object does not yet appear. It is.

  Therefore, in one embodiment of the present invention, the luminance level of the background light and the luminance level of the face are calculated as virtual luminance levels by calculation based on the video signal acquired by the monitoring camera 110.

  For this calculation, first, the reflectance ρ of the installation space of the monitoring camera 110 is assumed in accordance with the monitoring area 20, the ceiling, the wall, the floor, the lighting fixture, and the frontage, depth, The calculation is performed in consideration of the room index according to the height from the task plane (this time the face 30f of the person 30) to the light source.

  Next, the virtual luminance level is calculated by the calculation represented by the following equation (1).

図５および図６において、図中、撮像視野１０内に位置する人物３０の顔３０ｆの輝度が、図中、上記位置よりも左に位置する人物３０の顔３０ｆの輝度よりも高い場合が順光と判定される場合であり、これと反対の場合が逆光と判定される場合である。

5 and 6, the brightness of the face 30f of the person 30 located in the imaging visual field 10 is higher than the brightness of the face 30f of the person 30 located on the left side in the figure. This is a case where the light is determined, and the opposite case is a case where it is determined that the light is back.

FIG. 7 is a diagram illustrating a determination criterion in the case of determining the suitability (forward light and backlight) of the light irradiation state on the main subject based on the imaging output. FIG. 7A illustrates a standard for determining suitability for the light irradiation state as in FIGS. 5 and 6.
In the example of FIG. 7A, the three layers (weak forward light, medium forward light, strong forward light) with respect to the follow light state as in FIG. 5, and the three layers (weak backlight, with respect to the backlight state as in FIG. The determination result can be obtained as any one of the evaluation results classified into medium backlight and strong backlight. Evaluation results based on such determination criteria are output from the light irradiation state estimation unit 120 in the monitoring camera system 100 of FIG.

  FIG. 7B is a diagram exemplifying another determination criterion for determining the suitability (forward light and backlight) of the light irradiation state with respect to the main subject.

  In the example of FIG. 7 (b), two reflectors (or predetermined areas differing in the extent to which a person's shadow is projected according to the light irradiation state are used. In this example, the color plane is Use). These color planes are placed (set) on the flow line (passage) of a person, and their brightness values (imaging output levels corresponding to those by the surveillance camera) are divided into three stages in descending order: “bright” “dim” The determination is made as shown in the figure depending on the combination of “dark”.

  In this case, it is desirable that each color plane is set to have a width approximately equal to the passage width so that a difference in luminance value due to a person's shadow can be identified no matter which person passes in the passage width direction.

  In the example of FIG. 7B, as is clear with reference to the drawing, the combination of the luminance values E1 and E2 of the color planes is related to the relative positions of the schematically drawn person and the two color planes. In the case where it is determined that the light is forward light and the case where it is determined that the light is backlight, five sets of standards are set.

  Note that the example of FIG. 7A is excellent in that there is no hindrance in the determination even if the reflecting surfaces 41 and 42 are small enough to be inconspicuous. On the other hand, the example of FIG. 7B is excellent in that it is not necessary to measure the luminance value in advance.

  Corresponding to this evaluation result, the light environment adjusting unit 130 described above with reference to FIG. 1 adjusts the light to the main subject 30 by the light adjusting device 131, and together with this (or independently), The light control device 132 adjusts the amount of illumination light to the main subject 30.

  FIG. 8 is a block diagram showing an embodiment of the surveillance camera and the light environment adjusting device of the present invention.

  FIG. 8 shows a state in which the monitoring camera 800 and the light environment adjusting device 300 are connected by a signal line. The monitoring camera 800 is a mode having both the functions of the monitoring camera 110 and the light irradiation state estimation unit 120 of FIG. 8 is substantially equivalent to the light environment adjusting unit 130 in FIG.

  The monitoring camera 800 includes an imaging optical system 801, an imaging circuit unit 810, a light irradiation state estimation data calculation unit 820, and a light irradiation state estimation data supply unit 830.

  The imaging optical system 801 forms an image corresponding to the subject in the imaging field. The imaging circuit unit 810 photoelectrically converts an image from the imaging optical system 801 and performs predetermined signal processing to obtain a video signal. The light irradiation state estimation data calculation unit 820 is a light irradiation state estimation data corresponding to the light irradiation state of the main subject in the imaging field based on the signal corresponding to the reflection surface described above in the video signal. Is calculated. Accompanying this calculation, as described above with reference to FIGS. 5 to 6, it is possible to obtain data for determining the suitability of the light irradiation state on the main subject.

  The light irradiation state estimation data output unit 820 outputs the light irradiation state estimation data (including data on the result of determination of the suitability of the light irradiation state) and is suitable for signal processing at the subsequent stage in the light irradiation state estimation data supply unit 830. The signal is converted into a signal of the form and supplied to the light environment adjusting device 300.

  The light irradiation situation estimation data calculation unit 820 and the light irradiation situation estimation data supply unit 830 in the monitoring camera 800 constitute a light irradiation situation estimation unit 120a. The light irradiation state estimation unit 120a corresponds to the light irradiation state estimation unit 120 in FIG.

  In the light environment adjustment apparatus 300, the light irradiation state estimation data receiving unit 310 receives the light irradiation state estimation data from the monitoring camera 800 (the light irradiation state estimation data supply unit 830).

  The light irradiation state estimation data receiving unit 310 converts the light irradiation state estimation data received as described above into a signal in a form suitable for the lighting adjustment device 131 and the dimming device 132 (depending on the specifications of these devices 131 and 132). Then, the form of the signal is amplified without being converted), distributed, and supplied to the lighting adjustment device 131 and the dimming device 132, respectively.

  The daylighting adjustment device 131 operates any one of a blind, a roll screen, and a curtain as a light transmission state variable member that adjusts the transmission state of external light by a servo mechanism that responds to the light irradiation state estimation data. The lighting for the main subject is adjusted by adjusting the transmission state of the subject.

  The daylighting adjustment device 131 applies a driving voltage corresponding to the light irradiation state estimation data to the electro-optical light transmission variable variable laminate as a light transmission state variable member that adjusts the transmission state of external light. The lighting for the main subject is adjusted by adjusting the light transmission state (light transmittance). As this electro-optical light transmission variable variable laminate, for example, “um” smart window (registered trademark) is known.

  In addition, the other daylighting adjustment device 131 is provided with a plurality of LEDs that emit light from the semiconductor element as a light transmission state variable member that adjusts the transmission state of the external light in a window frame or the like where the external light and the room are in contact with each other. By controlling the energization output by connecting to a DC power source whose output is adjusted according to the situation estimation data, the lighting for the main subject is adjusted by adjusting the transmission situation (light transmittance) of the external light.

  On the other hand, the light control device 132 functions as a light amount adjusting unit that adjusts the amount of illumination light applied to the main subject in response to the light irradiation state estimation data. The light amount adjustment unit includes a supply power control circuit that controls the supply power of the illumination light to the light source, and adjusts the amount of illumination light applied to the main subject.

  Next, referring to the respective flowcharts, the operation of adjusting the irradiation amount of the illumination light to the main subject by driving the blind as the light transmission state variable member, the roll screen, and the electro-optical light transmission characteristic variable laminated plate explain.

  FIG. 9 is a flowchart showing the operation of the light environment adjusting apparatus according to the embodiment of the present invention that adjusts the daylighting of the main subject by driving the blind slats. The light environment adjusting device in this case corresponds to the light environment adjusting unit 130 in FIG. 1 and corresponds to the daylight adjusting device 131 in the light environment adjusting device 300 in FIG.

  As for the installation status of the blinds, it is assumed that the configuration as described above with reference to FIGS. 2 and 3 is adopted. That is, the blind 210 is provided so as to moderately suppress the incident of external light (sunlight) LS into the imaging visual field 10 of the monitoring camera 110 that is the monitoring region 20.

  In each embodiment illustrated below, the recognition itself of the presence or absence of an intruder into the imaging field of view 10 of the monitoring camera 110 has already been realized with a practical accuracy by a known image recognition technique. Is omitted.

  The blind 210 is configured such that the angle of the slat 211 can be adjusted by, for example, a servo mechanism that operates in response to light irradiation state estimation data from the light irradiation state estimation unit 120 of FIG.

The blind 210 continuously and automatically adjusts the angles of the slats 211 in accordance with an energy saving operation mode in which sunlight is shielded from sunlight in summer and solar radiation is introduced in winter to save energy. Or if it is the blind 210 facing the office room, VDT (Visual Display
Terminal) The slat 211 is continuously and automatically adjusted so as to reduce the dazzling feeling according to the comfortable viewing environment driving mode aiming to ensure a comfortable viewing environment of the screen.

  These normal operation modes indicate the normal mode of the room according to the purpose of use of the room, the intention of the user / manager of the room, and the like.

  In this state, before it is recognized based on the video signal of the monitoring camera 110 that there is a person who has entered the imaging field of view 10 of the monitoring camera 110 (step S901: No), the above-described energy saving operation mode or comfortable viewing environment. The operation mode and the like are continued (step S909), and the servo mechanism that drives the slat 211 is stopped and maintains the current state.

  When it is recognized from this state that there is a person who has entered the imaging field of view 10 of the monitoring camera 110 (step S901: Yes), the lighting adjustment device 131 shifts to the light environment control mode for face authentication (step S902). . The face authentication light environment control mode in the case of FIG. 9 is an operation mode for performing lighting adjustment by the blind in particular.

  In step S902, when the mode shifts to the face authentication light environment control mode (lighting adjustment operation by blinds), for example, it waits for the arrival of the photometric data acquisition timing set in a predetermined cycle (step S903: No). When this timing comes (step S903: Yes), photometric data based on the video signal output from the monitoring camera 110 is acquired (step S904).

  The photometric data in step S904 is acquired from the light irradiation state estimation unit 120 in FIG. 1 or from the light irradiation state estimation unit 120a (the light irradiation state estimation data supply unit 830) of the monitoring camera 800 in FIG. To do.

  Next, based on the photometric data acquired in step S904, it is determined whether the light environment at the time is in an appropriate state (step S905).

  When it is determined in step S905 that the light environment at that time is appropriate (step S905: Yes), the above-described energy saving operation mode or comfortable vision environment operation mode is continued (step S909), and the slat 211 is driven. The servo mechanism remains in a resting state.

  On the other hand, when it is determined in step S905 that the light environment at that time is not appropriate (step S905: No), the servo mechanism is activated, and the slat 211 is driven to adjust the angle (step S906).

  At a stage where the angle of the slat 211 is adjusted to some extent in step S906, photometric data at that time is acquired (step S907).

  Then, based on the photometric data acquired in step S907, it is determined whether or not the light environment at the time has reached an appropriate state (step S908).

  When it is determined in step S908 that the light environment has reached an appropriate state (step S908: Yes), the above-described energy saving operation mode or comfortable vision environment operation mode is restored (step S909), and the servo that drives the slat 211 is obtained. The mechanism returns to a dormant state.

  On the other hand, when it is determined in step S908 that the light environment is still not appropriate (step S908: No), the process returns to step S906.

  That is, a feedback loop of step S906 → step S907 → step S908 → step S906 is formed, and the adjustment of the angle of the slat 211 is continued until the light environment reaches an appropriate state.

  FIG. 10 is a flowchart showing the operation of the light environment adjusting apparatus as another embodiment of the present invention for adjusting the lighting for the main subject by driving the roll screen. In this case as well, as in the case of FIG. 9, the light environment adjusting device corresponds to the light environment adjusting unit 130 in FIG. 1, and also corresponds to the daylighting adjusting device 131 in the light environment adjusting device 300 in FIG. .

  And about the installation condition of a roll screen, it replaces with the above-mentioned blind with reference to FIG. 2 and FIG. 3, and assumes that this is replaced with the roll screen. In other words, the roll screen is provided so as to appropriately suppress and adjust the incidence of external light (sunlight) LS into the imaging field of view 10 of the monitoring camera 110 that is the monitoring region 20.

  In the embodiment described above with reference to FIG. 9, in order to save energy, Hirao continuously introduces solar radiation according to an energy saving operation mode in which solar radiation is shielded in summer and solar radiation is introduced in winter. If the blind 210 is automatically adjusted to the room or faces the office room, the slat 211 continues to reduce the dazzling feeling according to the comfortable viewing environment operation mode aiming to ensure a comfortable viewing environment on the VDT screen. In FIG. 10, it is assumed that the face is in the face authentication light environment control mode. That is, the mode in which the lighting adjustment operation by the roll screen is continuously performed is maintained regardless of the presence or absence of an intruder in the imaging field 10 of the monitoring camera 110.

  In this state, for example, it waits for the arrival of the photometric data acquisition timing set in a predetermined cycle (step S1001: No), and when this timing comes (step S1001: Yes), the video from the monitoring camera 110 is displayed. Photometric data based on the signal output is acquired (step S1002).

  The photometric data is acquired in step S1002 from the light irradiation state estimation unit 120 in FIG. 1 or from the light irradiation state estimation unit 120 (its light irradiation state estimation data supply unit 230) of the monitoring camera 200 in FIG. To do.

  Next, based on the photometric data acquired in step S1002, it is determined whether or not the light environment at the time is in an appropriate state (step S1003).

  If it is determined in step S1003 that the light environment at that time is appropriate (step S1003: Yes), no special daylighting adjustment is required, and therefore the servo mechanism does not operate and the roll screen is wound up at that time. Maintain quantity.

  On the other hand, when it is determined in step S1003 that the light environment at that time is not appropriate (step S1003: No), the servo mechanism is activated, and the roll screen is driven to adjust the amount of winding (step S1004). .

  At a stage where the roll screen winding amount is adjusted to some extent in step S1004, photometric data at that time is acquired (step S1005).

  Then, based on the photometric data acquired in step S1005, it is determined whether or not the light environment at the time has reached an appropriate state (step S1006).

  When it is determined in step SS1006 that the light environment has reached an appropriate state (step SS1006: Yes), it is not necessary to perform further lighting adjustment, so the servo mechanism is stopped and the roll screen is wound up at that time. Maintain quantity.

  On the other hand, when it is determined in step S1006 that the light environment is not yet appropriate (step S1006: No), the process returns to step S1004.

  That is, a feedback loop of step S1004 → step S1005 → step S1006 → step S1004 is formed, and adjustment of the roll screen winding amount is continued until the light environment reaches an appropriate state.

  FIG. 11 is a flowchart showing the operation of the light environment adjusting apparatus as still another embodiment of the present invention that adjusts the light transmission characteristic of the electro-optical light transmission characteristic variable laminated plate to adjust the lighting for the main subject. . In this case as well, as in the case of FIG. 9, the light environment adjusting device corresponds to the light environment adjusting unit 130 in FIG. 1, and also corresponds to the daylighting adjusting device 131 in the light environment adjusting device 300 in FIG. .

  As described above, the electro-optical light transmission characteristic variable laminate is a member that can adjust the transmission state (light transmittance) of external light by applying a driving voltage. For example, the “um” smart window ( Registered trademark) and the like.

  With respect to the installation state of the electro-optical light transmission property variable laminate, a form in which this electro-optical light transmission property variable laminate is applied as the window glass 2110 as described above with reference to FIGS. 2 and 3 is adopted. Yes. That is, the electro-optical light transmission characteristic variable laminated plate 2110 is provided so as to moderately suppress and adjust the incidence of external light (sunlight) LS into the imaging visual field 10 of the monitoring camera 110 that is the monitoring region 20. ing.

  The light transmission characteristic of the electro-optical light transmission characteristic variable laminated plate 2110 can be adjusted by, for example, an applied voltage from a drive circuit that operates in response to light irradiation state estimation data from the light irradiation state estimation unit 120 of FIG. It is configured.

  The electro-optic light transmission variable variable laminated plate 2110 automatically adjusts its light transmission characteristics according to an energy-saving operation mode in which Hirao shields solar radiation in summer and introduces solar radiation in winter to save energy. ing. Alternatively, the electro-optic light transmission variable variable laminate 2110 facing the office room is electro-optical so as to reduce the glare according to the comfortable viewing environment operation mode aiming to ensure a comfortable viewing environment of the VDT screen. The light transmission characteristic variable laminate 2110 is continuously automatically adjusted.

  In this state, before it is recognized that there is a person who has entered the imaging field of view 10 of the monitoring camera 110 based on the video signal of the monitoring camera 110 (step S1101: No), the above-described energy saving operation mode or comfortable viewing environment. The operation mode and the like are continued (step S1109), and the servo mechanism that drives the slat 211 is stopped and maintains the current state.

  When it is recognized from this state that there is a person who has entered the imaging field of view 10 of the monitoring camera 110 (step S1101: Yes), the daylighting adjustment device 131 shifts to the light environment control mode for face authentication (step S1102). . The face authentication light environment control mode in the case of FIG. 11 is an operation mode in which the daylighting is adjusted by the window glass 2110 which is an electro-optical light transmission variable variable laminate.

  In step S1102, when the mode shifts to the face authentication light environment control mode (lighting adjustment operation using the electro-optic light transmission variable variable laminate), for example, waiting for the arrival of the photometric data acquisition timing set periodically. (Step S1103: No) When this timing comes (Step S1103: Yes), photometric data based on the video signal output from the monitoring camera 110 is acquired (Step S1104).

  The photometric data in step S1104 is acquired from the light irradiation state estimation unit 120 in FIG. 1 or from the light irradiation state estimation unit 120 (its light irradiation state estimation data supply unit 230) of the monitoring camera 200 in FIG. To do.

  Next, based on the photometric data acquired in step S1104, it is determined whether the light environment at the time is in an appropriate state (step S1105).

  When it is determined in step S1105 that the light environment at that time is appropriate (step S1105: Yes), the above-described energy saving operation mode or comfortable vision environment operation mode is continued (step S1109), and electro-optical light transmission is performed. The drive circuit that drives the variable characteristic laminate 2110 maintains a steady state corresponding to the energy saving operation mode or the comfortable visual environment operation mode.

  On the other hand, if it is determined in step S1105 that the light environment at that time is not appropriate (step S1105: No), the drive circuit is activated and the drive voltage applied to the electro-optical light transmission variable variable laminate 2110 is changed. The light transmission characteristics are adjusted (step S1106).

  In step S1106, the light transmission characteristic of the electro-optical light transmission characteristic variable laminate (window glass) 2110 is changed, and the photometric data at that time is acquired (step S1107).

  Then, based on the photometric data acquired in step S1107, it is determined whether or not the light environment at the time has reached an appropriate state (step S1108).

  When it is determined in step S1108 that the light environment has reached an appropriate state (step S1108: Yes), the above-described energy saving operation mode or comfortable vision environment operation mode is restored (step S1109), and the electro-optical light transmission characteristics are obtained. The drive circuit for driving the variable laminate plate 2110 returns to a steady state corresponding to the energy saving operation mode or the comfortable visual environment operation mode.

  On the other hand, when it is determined in step S1108 that the light environment is not yet appropriate (step S1108: No), the process returns to step S1106.

  That is, a feedback loop of step S1106 → step S1107 → step S1108 → step S1106 is formed, and adjustment of the light transmission characteristic of the electro-optical light transmission characteristic variable laminated plate 2110 is continued until the light environment reaches an appropriate state. .

  FIG. 12 is a conceptual diagram showing a surveillance camera system as an embodiment of the present invention that performs light control on a main subject by adjusting the irradiation amount of illumination light.

  In the monitoring camera system 1200 of FIG. 12, the monitoring camera 110 is installed so as to include a predetermined monitoring area 20 in the imaging field of view 10. This installation takes the form of fixedly or semi-fixedly attached to an appropriate position of the ceiling surface 12 so as to secure a field of view for monitoring visitors to the entrance of the building, for example. In this embodiment, the monitoring area 20 is set equal to the imaging field of view 10 as in the case of FIG.

  Two reflecting surfaces 41 and 42 are set on the floor surface 11 in the monitoring region 20 in the imaging field 10 of the monitoring camera 110. The imaging output (luminance level) of the reflection surfaces 41 and 42 by the monitoring camera 110 is schematically shown by arrows E1 and E2 as shown in the figure. With reference to FIG. 7 that illustrates the criteria for this determination, the determination of forward light / backlight is performed for the light environment related to imaging at the time when these values are obtained based on the values of E1 and E2. As described above, the case of FIG. 12 shows a case where sunlight as external light acts as backlight.

  When the person 30 as the main subject enters the monitoring area 20, the monitoring area 20 is in the imaging field of view 10 of the monitoring camera 110, so that the person 30 is recorded by the monitoring camera 110 that is always operating. At this time, in particular, face authentication is performed based on a record related to the face 30f of the person 30.

  For this reason, in FIG. 12, the imaging exposure amount Evx related to the face authentication surface 30 fc assumed in the range of height x and the range of y that is a constant movement range along the flow line of the intruder. It is necessary to adjust the light environment so that the value becomes an appropriate value.

  In the present embodiment, the light environment is adjusted by adjusting the amount of illumination light applied by adjusting the power supply to the lamp.

  In the example of FIG. 12, the ceiling surface 12 having a height from the floor level FL of the floor surface 11 has a ceiling surface embedded fluorescent lamp or a fluorescent lamp embedded along the flow direction (y direction in the drawing) assumed for the intruder. A plurality (six in this example) of lamps 1230 (1231, 1232, 1233, 1234, 1235, and 1236) using LED bulbs or the like are installed.

  The lighting environment is adjusted by dimming in such a manner that the amount of illumination light emitted from these lamps 1231, 1232, 1233, 1234, 1235, and 1236 is controlled individually. This may take a form in which some of the aligned sequential lamps 1231, 1232, 1233, 1234, 1235, and 1236 are turned on and the other parts are turned off.

  As described above, the light environment is adjusted by adjusting the amount of illumination light by adjusting the power supply to the lamp, and the light environment adjusting device 30 in FIG. 1 and the light environment adjusting device 300 in FIG. This is an embodiment and corresponds to the dimmer 132 described above with reference to FIGS. 1 and 8.

  FIG. 13 is a flowchart showing the operation of the light environment adjusting device in the monitoring camera system of FIG.

  The lamps 1231, 1232, 1233, 1234, 1235, and 1236 in FIG. 12 are used to save energy during the summer, and in the summer, all or some of the lamps are adjusted to the relatively long daylight hours. The lights are turned off, and the on / off is automatically adjusted according to the energy-saving operation mode in which the room is turned on sequentially so that the room does not become too dark in short winter hours. Alternatively, as another embodiment, Hirao assumes that a person manually turns on and off the switch. As another embodiment, when Hirao is turned off for energy saving, the presence of a person is detected by a human sensor that detects the movement of a person using a pyroelectric infrared sensor or the like. It shall operate to be on.

  In this state, before the fact that there is a person who has entered the imaging field of view 10 of the monitoring camera 110 based on the video signal of the monitoring camera 110 (step S1301: No), the above-described energy saving operation mode is continued ( In step S1309), the servo mechanism for driving the slat 211 is stopped and maintains the current state.

  When it is recognized from this state that there is a person who has entered the imaging field of view 10 of the monitoring camera 110 (step S1301: Yes), the dimmer 132 shifts to the face authentication light environment control mode (step S1302). .

  In the light environment control mode for face authentication in the case of FIG. 13, in particular, light adjustment is performed by individually adjusting the power supplied to the lamps 1231, 1232, 1233, 1234, 1235, and 1236. This is an operation mode for adjusting the environment.

  In step S1302, when the mode is shifted to the face authentication light environment control mode (light environment adjustment by dimming), for example, it waits for the arrival of the photometric data acquisition timing set in a predetermined cycle (step S1303: No). When this timing comes (step S1303: Yes), photometric data based on the video signal output from the monitoring camera 110 is acquired (step S1304).

  The photometric data is acquired in step S1304 from the light irradiation state estimation unit 120 in FIG. 1 or from the light irradiation state estimation unit 120 (its light irradiation state estimation data supply unit 230) of the monitoring camera 200 in FIG. To do.

  Next, based on the photometric data acquired in step S1304, it is determined whether or not the light environment at the time is in an appropriate state (step S1305).

  In this determination, basic information on lighting calls such as total luminous flux (φ × N) incident on the face authentication surface 30fc, illumination rate (U), maintenance rate (M), and illumination (lamp) to the face authentication surface 30fc. By considering the basic building information such as the distance (r) and the angle (θ) at which the face authentication surface 30fc is viewed from the lighting (lamp), it is possible to obtain a determination result that is more realistic.

  When it is determined in step S1305 that the light environment at that time is appropriate (step S1305: Yes), the above-described energy saving operation mode or comfortable vision environment operation mode is continued (step S1309), and the lamps 1231, 1232, Dimming relating to 1233, 1234, 1235, and 1236 maintains a state corresponding to the energy saving operation mode or the comfortable visual environment operation mode.

  On the other hand, when it is determined in step S1305 that the light environment at that time is not appropriate (step S1305: No), the light control device 132 is activated, and the lamps 1231, 1232, 1233, 1234, 1235, and 1236 are connected. Dimming is performed such that the supplied power is individually adjusted, thereby adjusting the light environment (step S1306).

  In particular, for the face authentication surface 30fc, when the action of backlight due to sunlight as the external light is remarkable, the external light is separately provided by a blind, a roll screen, or an electro-optical light transmission variable variable laminated plate of window glass. May be cut off, and only a part or all of the lamps 1231, 1232, 1233, 1234, 1235, and 1236 may be used to ensure the light environment of the following light by these artificial light sources.

  Alternatively, among the lamps 1231, 1232, 1233, 1234, 1235, and 1236, the light irradiation intensity of the lamp 1236 that most significantly acts to obtain the light environment of the front light on the face authentication surface 30fc is maximized. Thus, for the lamps 1235, 1234, 1233, 1232, and 1231, even if the light environment is adjusted so as to obtain an appropriate imaging exposure amount by performing dimming that sequentially reduces the light irradiation intensity. Good.

  In step S1306, the light environment is adjusted by dimming, and the photometric data at that time is acquired (step S1307).

  Then, based on the photometric data acquired in step S1307, it is determined whether or not the light environment at the time has reached an appropriate state (step S1308).

  When it is determined in step S1308 that the light environment has reached an appropriate state (step S1308: Yes), the above-described energy saving operation mode or comfortable vision environment operation mode is restored (step S1309), and the lamps 1231, 1232, and 1233 are returned. , 1234, 1235, and 1236 return to the state corresponding to the energy saving operation mode or the comfortable visual environment operation mode.

  On the other hand, when it is determined in step S1308 that the light environment is still not appropriate (step S1308: No), the process returns to step S1306.

  That is, a feedback loop of step S1306 → step S1307 → step S1308 → step S1306 is formed, and the adjustment of the light environment is continued by dimming until the light environment reaches an appropriate state.

  In all of the modes of FIGS. 9, 10, 11, and 13, the feedback control is applied to the adjustment of the light environment, but the relationship between the light environment data as the controlled amount and the adjustment amount is specified. It is also possible to obtain a sufficient amount of data in advance and control in an open loop so that this data is reflected.

  FIG. 14 is a diagram for explaining an illuminance calculation method for face authentication applicable to the embodiment of the present invention.

  FIG. 14A shows a space for maintaining the light environment at a certain level in order to obtain the imaging exposure amount Evx related to the face authentication surface 30fc described above with reference to FIG. A photometric space) is conceptually shown by a broken line. x is the range of the height from the floor level FL, y is the distance that the intruder moves along the direction of the flow line within the time required to obtain the photometric data in the monitoring area, and w is the angle of view of the monitoring camera. The width is appropriately determined according to (expansion of imaging field of view). For x, the main area for face authentication is appropriately determined depending on the use of the building.

  FIG. 14B is a diagram illustrating a method for calculating the vertical plane average illuminance by the four-point method with respect to the photometric space of FIG. A microphotometric space is assumed for each of the four vertical areas in the photometric space of the rectangular parallelepiped in FIG. 14A, and the photometric data of the entire photometric space is calculated as an average value of the photometric data related to these. This calculation is based on the following equation (2).

また、図１４（ｃ）は、図１４（ａ）の測光空間に対し、５点法による鉛直平面平均照度の算定手法を表す図である。図１４（ａ）における直方体の測光空間に関し図示のように５箇所の部位について微小測光空間を想定し、これら微小測光空間に関する測光データを用いて、次の（３）式によって測光空間全体の測光データを算定する。

FIG. 14C is a diagram showing a method for calculating the vertical plane average illuminance by the five-point method with respect to the photometric space of FIG. As shown in FIG. 14A, assuming a photometric space of a rectangular parallelepiped as shown in the drawing, microphotometric spaces are assumed at five locations, and photometric data relating to these microphotometric spaces is used to measure the entire photometric space using the following equation (3) Calculate the data.

ところで、本発明の実施の形態では、監視対象となる監視領域への進入者の顔を撮像して顔認証を行うに際し、当該進入者の出現以前に、顔認証を行う監視領域内の予定した空間を対象にして、予め、撮像に適した光環境を整えておく。

By the way, in the embodiment of the present invention, when performing face authentication by capturing the face of an intruder into the monitoring area to be monitored, the face in the monitoring area for performing face authentication is scheduled before the appearance of the intruder. A light environment suitable for imaging is prepared in advance for the space.

  In order to prepare the light environment in this way, photometry is performed in a space for performing face authentication. Then, the light exposure and the light adjustment are adjusted according to the photometric result, so that an imaging exposure amount in an appropriate range is ensured.

  As described above, a space for performing photometry for a predetermined space in the monitoring area where face authentication is performed without waiting for the appearance of an intruder is referred to as a photometric space in the above description with reference to FIG. Called.

  In the embodiment of the present invention, a reflective member (reflector plate) having a known reflectivity on a reflective surface at an appropriate position in a predetermined monitoring area is provided so that significant photometry can be performed even in the absence of an intruder. ) Was installed.

  FIG. 15 is a diagram used for explaining the basic concept of the reflector arrangement and the illuminance calculation method applied to the embodiment of the present invention.

  In a three-dimensional Cartesian coordinate system in which the vertical z-axis is added to the horizontal plane of the x-axis and y-axis, the illuminance on the horizontal plane of the microcube is set as the horizontal plane illuminance Eh, and the illuminance on the vertical plane of the microcube is set as the vertical plane illuminance Ev. Define each.

  The horizontal plane illuminance Eh described above is measured by performing photometry by installing a reflecting plate on the floor (level position of FL in FIG. 12). Further, it is measured by performing photometry by installing the reflector at a level position (assumed face height) having a certain height from the floor surface.

  Further, the vertical plane illuminance Ev is measured by performing photometry by installing a reflector on a vertical wall surface of a building or the like. In addition, a reflector is installed at a level position (assumed face height) having a certain height from the floor so that the reflector is vertical, and this reflector is used as a subject for measurement. Is done.

  In the surveillance camera system of the present invention, the positions of the sample points for detecting the horizontal plane illuminance Eh and the vertical plane illuminance Ev described above are set in consideration of the face authentication flow line and the light incident direction assumed along the movement of the intruder. .

  The position of the sample point is basically set in consideration of the light irradiation amount and the degree of attenuation along the irradiation direction of the irradiation amount. Several examples of this setting will be illustrated below.

  FIG. 16 is a diagram illustrating the positions of sample points for detecting the horizontal plane illuminance Eh and the vertical plane illuminance Ev when light is irradiated from behind the authentication flow line.

  As shown in FIG. 16A, a three-dimensional orthogonal coordinate system is set as described above with reference to FIG. 15, and the authentication flow line at this time is parallel to the y-axis. To do. In addition, the photometric space is assumed so that three ridges of the cube perpendicular to each other are parallel to the x-axis, y-axis, and z-axis in the orthogonal coordinate system.

  FIG. 16B shows a state in which two points separated along the authentication flow line (that is, along the y-axis) are set as sample points for detecting the horizontal plane illuminance Eh.

  Photometric data Eh-1 is detected from the first sample point close to the starting end of the authentication flow line, and photometric data Eh-2 is detected from the second sample point far from the starting end of the authentication flow line.

  FIG. 16C shows a state in which two points separated along the authentication flow line (that is, along the y-axis) are set as sample points for detecting the vertical surface illuminance Ev.

  Photometric data Ev-1 is detected from the first sample point close to the starting end of the authentication flow line, and photometric data Ev-2 is detected from the second sample point far from the starting end of the authentication flow line.

  In the case of FIGS. 16 (b) and 16 (c), the first sample point and the second sample point are the second sample points that are shaded by the reflector placed at the first sample point. Care must be taken to ensure that the sample points are properly spaced so that they are not projected onto the reflector placed on the screen.

  FIG. 17 is a diagram illustrating the positions of sample points for detection of the horizontal plane illuminance Eh and the vertical plane illuminance Ev when light is irradiated from the side toward the authentication flow line.

  As shown in FIG. 17A, a three-dimensional orthogonal coordinate system is set as described above with reference to FIG. 15, and the authentication flow line at this time is parallel to the y-axis. To do. In addition, the photometric space is assumed so that three ridges of the cube perpendicular to each other are parallel to the x-axis, y-axis, and z-axis in the orthogonal coordinate system. Light (for example, sunlight) is irradiated from the side toward the authentication flow line in such a photometric space.

  FIG. 17B shows a state in which two points separated along the direction perpendicular to the authentication flow line (that is, along the x axis) are set as sample points for detecting the horizontal illuminance Eh.

  Photometric data Eh-1 is detected from the first sample point close to the starting end of the authentication flow line, and photometric data Eh-2 is detected from the second sample point far from the starting end of the authentication flow line.

  FIG. 17C shows a state in which two points separated from each other along the direction orthogonal to the authentication flow line (that is, along the x axis) are set as sample points for detecting the vertical surface illuminance Ev.

  Photometric data Ev-1 is detected from the first sample point close to the starting end of the authentication flow line, and photometric data Ev-2 is detected from the second sample point far from the starting end of the authentication flow line.

  FIG. 18 is a diagram illustrating the positions of sample points for detection of horizontal plane illuminance Eh and vertical plane illuminance Ev when light is irradiated from the front side toward the authentication flow line.

  As shown in FIG. 18A, a three-dimensional orthogonal coordinate system is set as described above with reference to FIG. 15, and the authentication flow line at this time is parallel to the y-axis. To do. In addition, the photometric space is assumed so that three ridges of the cube perpendicular to each other are parallel to the x-axis, y-axis, and z-axis in the orthogonal coordinate system. Light (for example, sunlight) is irradiated from the front side toward the authentication flow line to such a photometric space.

  FIG. 18B shows a state in which two points separated along the direction of the authentication flow line (that is, along the y axis) are set as sample points for detecting the horizontal plane illuminance Eh.

  Photometric data Eh-1 is detected from the first sample point close to the starting end of the authentication flow line, and photometric data Eh-2 is detected from the second sample point far from the starting end of the authentication flow line.

  FIG. 18C shows a state in which two points separated along the direction of the authentication flow line (that is, along the y-axis) are set as sample points for detecting the vertical surface illuminance Ev.

  Photometric data Ev-1 is detected from the first sample point close to the starting end of the authentication flow line, and photometric data Ev-2 is detected from the second sample point far from the starting end of the authentication flow line.

  In the case of FIGS. 18B and 18C, the first sample point and the second sample point are the first sample point that is behind the reflector placed at the second sample point. Care must be taken to ensure that the sample points are properly spaced so that they are not projected onto the reflector placed on the screen.

  As described above, in FIGS. 16, 17, and 18, light is incident on the authentication flow line as in the case where light is incident from two or more openings and the light irradiation direction changes from time to time. When the irradiation direction changes with time, the irradiation angle of solar radiation may be calculated by a timer, and the position of the sample point applied to illuminance estimation (photometry) may be switched over time. In this case, a larger number of sample points as shown in FIGS. 16, 17, and 18 are set, and these are switched over time to obtain photometric data.

  FIG. 19 is a diagram illustrating the positions of sample points for illuminance detection under conditions where the incident direction of external light changes with respect to the direction of the authentication flow line.

  Depending on the operational status of the building, there may be a case where a large number of lamps are divided into groups, for example, and controlled so as to be turned on or off over time in groups. In such a case, the photometric space is assumed so that one ridge of the cube is parallel to the authentication flow line. Then, the sample points for illuminance detection are set in a cone-shaped body (a shape lacking the top as shown in the figure) in which the bottom surface is inscribed in the four sides of the bottom surface of the cube in the photometric space of the cube. The cones in this case are formed so as to define the criticality with respect to the range affected by the change in the direction of the light beam that changes as the lamps are turned on or off as described above.

  FIG. 20 is a diagram illustrating a simple illuminance calculation method applicable to the embodiment of the present invention.

  FIG. 20A is an image including the indoor wall surface 2001 acquired by the monitoring camera.

  In this simple illuminance calculation method, a partial image 2002 (its image data) including the number “3”, which is a pattern with a known reflectance, is cut out from the image of FIG.

  FIG. 20B is a diagram illustrating the cut-out partial image 2002.

  Then, two specific portions 2003 and 2004 of the number “3” in the partial image 2002 are set as sample points for detecting illuminance. These specific portions 2003 and 2004 can be set as minute regions in units of pixels. In this case, the sample points are selected by the method described above with reference to FIGS.

  For these sample points 2003 and 2004, a relational expression between illuminance and gray scale value is acquired in advance.

  Using the timer, the monitoring camera periodically acquires the image of FIG. 20A and cuts out the partial image 2002 of FIG. 20B based on the acquired image.

  For these sample points 2003 and 2004, the illuminance is simply calculated based on the illuminance and the gray scale value and these relational expressions acquired in advance.

10 …………………………………… Imaging field 11 ………………………………… Floor surface 20 …………………………………… Monitoring Area 30 …………………………………… Main subject (person)
30f …………………………………… Face 41, 42 ……………………… Reflecting surface 100 …………………………………… Monitoring camera system 110… ……………………………… Surveillance Cameras 120, 121a …………………… Light Irradiation State Estimator 121 …………………………………… Reflecting Member (Reflecting Plate)
121a ……………………………… Reflecting surface 130 …………………………………… Light environment control unit 131 …………………………………… Lighting control device 132 ………………………………… Dimmer 210 ………………………………… Blind 220 ………………………………… Reflector 221, 222, 223 ... Reflecting surface 230 ... …………………………………………………………………………………………………………………… Light Environment Control Device 310 ………… ... …………………… Light irradiation state estimation data receivers 410, 420, 430, 440 ... reflector 800 ………………………………… Monitoring camera 801 ………………… ……………… Imaging Optical System 810 ……………………………… Imaging Circuit Unit 820 ………………………………………… Light Irradiation State Estimation Data Calculation Unit 830. ... ………………………… Light Irradiation Status Estimation Data Supply Unit 1200 ……………………………… Monitoring Camera System 1230 ……………………………… Lamp 2001… …………………………… Wall 2002 ……………………………… Partial Images 2003, 2004 ………………… Sample Point 2110 ………………………… ...... Window glass

Claims (12)

A surveillance camera installed to include a predetermined surveillance area in the imaging field of view;
A light irradiation state estimation unit for estimating a light irradiation state with respect to a main subject in the imaging field of view of the monitoring camera and obtaining light irradiation state estimation data representing the estimation result;
Light environment adjustment installed outside the monitoring camera to adjust either or both of the lighting and illumination of the main subject in the imaging field based on the light irradiation state estimation data by the light irradiation state estimation unit And
A surveillance camera system comprising:   The light irradiation state estimation unit is configured for the main subject on the basis of an imaging output by the monitoring camera with respect to a reflection surface having a reflectance of one or more colors excluding black of a member arranged in the imaging field of view of the monitoring camera. The surveillance camera system according to claim 1, wherein the light irradiation state is estimated.   The monitoring camera system according to claim 2, wherein the light irradiation state estimation unit estimates a light irradiation state with respect to the main subject based on an imaging output of the monitoring camera with respect to the plurality of separated reflection surfaces. .   The light irradiation state estimation unit estimates a light irradiation state with respect to the main subject based on an imaging output by the monitoring camera with respect to the reflection surface having a plurality of divided regions whose brightness changes stepwise. The surveillance camera system according to claim 2.   The said light irradiation condition estimation part determines the suitability of the light irradiation condition with respect to the said to-be-photographed object based on contrast of several imaging output by the said monitoring camera with respect to the said several separated reflective surface. The surveillance camera system as described in.   The light environment adjusting unit includes a light transmission state variable member that adjusts the daylighting by adjusting the transmission state of external light in response to the light irradiation state estimation data by the light irradiation state estimation unit. The surveillance camera system according to claim 1.   The light transmission state variable member includes any one of a blind, a roll screen, a curtain, an electro-optical light transmission variable variable laminate, and an LED transparent variable screen. Surveillance camera system.   2. The light environment adjusting unit according to claim 1, further comprising: a light amount adjusting unit that adjusts the amount of illumination light applied to the main subject in response to light irradiation state estimation data from the light irradiation state estimating unit. Surveillance camera system.   The surveillance camera system according to claim 8, wherein the light amount adjustment unit includes a supply power control circuit that controls supply power of the illumination light to the light source. A light irradiation state estimation data calculation unit for calculating light irradiation state estimation data corresponding to the light irradiation state to the main subject in the imaging field;
The light irradiation state estimation data calculated by the light irradiation state estimation data calculation unit is applied to the light environment adjustment device installed outside so as to adjust the lighting or illumination of the main subject based on the light irradiation state estimation data. A light irradiation state estimation data supply unit to be supplied; and
A surveillance camera comprising: A light irradiation state estimation data receiving unit for receiving the light irradiation state estimation data from a monitoring camera that supplies light irradiation state estimation data corresponding to the light irradiation state to the main subject in the imaging field;
A light environment adjusting unit that adjusts either or both of lighting and illumination on the main subject based on the light irradiation state estimation data received in the light irradiation state estimation data reception;
A light environment adjusting device comprising: A light irradiation state estimation data calculating step for calculating light irradiation state estimation data representing the light irradiation state of the main subject in the imaging field of the surveillance camera;
A light environment adjustment step of adjusting either or both of the lighting and illumination of the main subject in the imaging field based on the light irradiation state estimation data calculated in the light irradiation state estimation data calculation step;
A light environment adjusting method characterized by comprising:

Images