JPH10162967A - Illumination controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illumination controller capable of measuring the illumination intensity on a desk or the like in an illumination region, controlling illumination according to brightness, and keeping the illumination intensity on the desk or the like constant independent of the outside light. SOLUTION: In an illumination control system having a TV cameral 1 which outputs an image signal, a digital image memory part 22 which memorizes the image information, an illumination intensity measuring part 2 having an operation part 21 which operates the illumination intensity in an image region based on brightness information of the image information memorized in the digital image memory part 22, an illumination control part 3 which produces and outputs the specified illumination control signal by the output from the illumination intensity measuring part 2, and a luminaire 4 which inputs an illumination control signal, controls an illumination load 41, and illuminates the specified region, a setting input part 23 which inputs fixing conditions of fixing height (h) and fixing angle θof the TV camera 1 is arranged, the operation part 21 operates the distance to a measuring point P1 within the image pick up region with the TV camera 1 based on the fixing condition information, and brightness information is corrected based on the operation result and illumination intensity is operated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting control device for controlling indoor lighting.

[0002]

2. Description of the Related Art Conventionally, in order to realize energy saving, it is necessary to control the brightness of a lighting load according to the intensity of external light entering from a window and to control the interior lighting of an office or the like to an appropriate brightness. Is being done. In many lighting control devices, the intensity of external light is detected by an appropriately installed external light illuminance sensor, and control such as blinking of an illumination load is performed. In addition, there has been proposed a lighting device in which an illuminance sensor is attached to a lighting device body, the intensity of external light is individually detected for each lighting device, and blinking control is performed by the lighting device itself.

FIG. 6 shows a window-side illumination control device disclosed in Japanese Patent Laid-Open Publication No. Sho 60-133693. The camera 1 outputs a video signal, and the camera 1 is arranged near a window in a room. An image pickup object 5 having a pattern provided in opposition to the object 5 and an illuminance measurement unit, which analyzes the pattern surface illuminance on the image pickup object 5 from an image of the image pickup object 5 by the camera 1 and converts the pattern into an image. An image processing device (not shown) for processing, an image discriminating device (not shown) for automatically discriminating the image-processed pattern control signal, and a predetermined illumination control signal generated and output by an output from the image discriminating device. A device provided with a control device corresponding to a lighting control means has been proposed.

[0004]

By the way, the above-mentioned window side lighting control device can realize energy saving by controlling only the window side lighting device 4 installed near the window 6. However, when controlling a lighting load in an office or the like, it is desirable to control a predetermined lighting load in response to a change in illuminance on a desk for performing office work.

[0005] Further, when an illuminance sensor is attached to a lighting fixture body and the intensity of external light is individually detected for each lighting fixture, it is troublesome to correlate the detection position of the illuminance sensor with a desk. Illuminance control is virtually impossible. Also, an illumination control device that detects the intensity of external light with an external light illuminance sensor that is appropriately installed and controls the brightness of an illumination load according to the intensity of the external light, or a window-side illumination control illustrated in FIG. In the apparatus, it is necessary to determine the control condition of the illumination load by obtaining the correlation between the measurement result of the illuminance on the desk and the image processing result of the object to be imaged by the external light illuminance sensor or the camera.
As a result, when the office layout changes,
Each time, it was necessary to find this correlation, which was troublesome.

The present invention has been made in view of the above circumstances, and has as its object to measure illuminance on a desk or the like in an illumination area and perform illumination control in accordance with the brightness.
It is an object of the present invention to provide a lighting control device capable of maintaining a constant illuminance on a desk or the like even when external light changes.

[0007]

According to a first aspect of the present invention, there is provided a lighting control apparatus, comprising: an imaging unit such as a television camera for outputting a video signal; a storage unit for storing video information; and a storage unit. Illuminance measuring means having a luminance / illuminance conversion means for performing illuminance calculation of an imaging region based on luminance information of video information stored in the illuminance information, and generating and outputting a predetermined illumination control signal based on an output from the illuminance measuring means A lighting control device for inputting a lighting control signal and controlling a lighting load to illuminate a predetermined area in a lighting control device, wherein a mounting condition of a mounting height and a mounting angle of the imaging unit is input. A condition input means is provided, and the
The illuminance conversion means calculates a distance to a measurement point in an imaging area by the imaging means based on the mounting condition information, and corrects luminance information based on the calculation result to calculate the illuminance. As a result, the luminance information obtained by the imaging unit is converted into the illuminance information at the measurement point.

According to a second aspect of the present invention, there is provided an illumination control device, wherein the illuminance measuring means according to the first aspect extracts a predetermined color area of the imaging area, and an area extracted by the area extracting means. Is set as an illuminance measurement mask and stored, and the luminance / illuminance conversion means calculates the illuminance based on video information in the illuminance measurement mask. Thereby, the illuminance calculation result is based on the luminance data of the measurement point in the area extracted by the illuminance measurement mask.

According to a third aspect of the present invention, there is provided an illumination control device, wherein an object to be imaged having a predetermined surface color is disposed at the measurement point according to the first or second aspect. As a result, the illuminance at the measurement point is measured with a predetermined surface color of the object to be imaged.

According to a fourth aspect of the present invention, the area extracting means is capable of extracting at least two different surface colors of the object. Thus, the lighting control means can control the lighting fixture based on the change in the surface color of the object.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a lighting control device according to the present invention will be described below with reference to FIGS.

FIG. 1 is a configuration diagram of a lighting control device. FIG. 2 is an explanatory diagram of a distance calculation of the lighting control device shown in FIG. FIG. 3 is an explanatory diagram of luminance / illuminance conversion of the illumination control device shown in FIG. FIG. 4 is an explanatory diagram of the operation of the mask storage means of the illumination control device shown in FIG. FIG. 5 is an explanatory diagram of control of the illumination control device shown in FIG. 1 based on a change in the surface color of the object to be imaged.

FIG. 1 shows a state in which a lighting control device performs lighting control of a lighting space such as an office. In this lighting space, a desk D is appropriately installed and a lighting control device is provided. The television camera 1 is attached to a position at a height h from the desk D, for example, at an angle of an attachment angle θ. Then, the illumination control device sets the upper surfaces of the desks D, D... As measurement points P1, P2, P3.

The illumination control device includes a television camera 1 serving as an image pickup unit for outputting a video signal, an illuminance measurement unit 2 serving as an illuminance measurement unit, and a predetermined illumination control signal output from the illuminance measurement unit 2. A lighting control unit 3 which is a lighting control means for generating and outputting, and a lighting load 41,
Lighting fixtures 4, 4,... Illuminating a predetermined area by controlling 1.
And

The television camera 1 is a color television camera which uses a color CCD element for an image pickup unit, for example, which is well known as a surveillance camera. However, this apparatus does not have an automatic aperture adjustment function and an automatic gain adjustment function in order to quantitatively measure the illuminance of the imaging area from the luminance information of the video screen. The television camera 1 correctly inputs video information such as the color or luminance of the imaging area S in a predetermined level range, and transmits a video signal of a color image through an image signal line L1 such as a coaxial cable to measure illuminance, which will be described later. Output to section 2.

An illuminance measuring section 2 is a digital video storage section 22 as storage means for storing video information, and the television camera 1 captures an image based on luminance information of the video information stored in the digital video storage section 22. A calculation unit 21 corresponding to a luminance / illuminance conversion unit for calculating the illuminance of the image pickup area S, and a mounting condition input unit for inputting the mounting height and mounting angle of the television camera 1 to the calculating unit 21. Setting input unit 23, an area extracting unit 24 that is an area extracting unit that extracts a predetermined color area of the imaging area S, and a mask that sets and stores the area extracted by the area extracting unit 24 as an illuminance measurement mask. And a mask storage unit 25 as storage means.

The digital video storage unit 22 is a two-dimensional memory constituted by, for example, a RAM (random access memory) as an image memory. The video information is stored as data and is output to an area extracting unit 24 described later.

The arithmetic unit 21 is, for example, a CPU, which inputs video information data from the digital video storage unit 2, and calculates the illuminance of the imaging area S based on the luminance of the video screen based on this data. In the calculation unit 21, a plurality of measurement points P1, P2, P
From the luminance data in the predetermined range of 3, a plurality of measurement points P1,
The average illuminance of each of P2, P3... Is calculated.

The setting input unit 23 is, for example, a ten-key switch, and is used to input mounting conditions such as a mounting height and a mounting angle of the television camera 1 used when the arithmetic unit 21 converts luminance data into illuminance data. . With this numeric key switch, the user inputs the mounting height h of the television camera 1 from the desk D and the mounting angle, that is, the tilt angle θ, according to the guidance displayed on a display device such as a monitor television (not shown). . The input data of the mounting height h and the tilt angle θ of the camera, that is, the mounting condition information, is sent to the arithmetic unit 21 and the TV camera 1 sends the measurement points P1,
.. Are used to calculate the distance to P2, P3,. The setting input unit 23 is also used in a later-described operation of storing the extraction area screen data in the mask storage unit 25.

Next, the measurement points P1, P2, P3,.
The principle of the distance calculation up to will be described with reference to FIG.

In FIG. 2, the mounting height of the television camera 1 is h (however, the height dimension from the surface of the desk D), the tilt angle of the television camera 1 is θ, and the imaging of the lens 11 and the imaging element 12 of the television camera. The distance between the lens 11 and the center point of the imaging area S (the point where the imaging center intersects the measurement plane) C is d; the angle between the measurement point P1 and the measurement plane is θ1; D1 is the distance between the measurement point P1 and the displacement from the center point C at which the image of the measurement point P1 is formed on the imaging surface;
The angle formed by the line connecting the point x1 and the measurement point P1 with the imaging center line CL is θx.

The distance from the television camera 1 to the measurement point P1 is the distance d1 between the lens 11 and the measurement point P1.
Then, in order to obtain this distance d1, first obtain θ1.

[0023]

(Equation 1)

Therefore, the distance d1 is

[0025]

(Equation 2)

When the mounting height h and the tilt angle of the television camera 1 are given θ, and the displacement x1 from the center point C that forms an image on the measurement point P1 imaging surface is known, the lens 11
The distance between and the measurement point P1 is determined. Then, as is well known, the illuminance is inversely proportional to the square of the distance from the light source, so that the above calculation is performed at each of the measurement points P1, P2,
By calculating the distances d1, d2, d3... Between the respective measurement points and the television camera 1 by multiplying the illuminance obtained for each measurement point by a coefficient inversely proportional to the square of the distance, The illuminance at the measurement point can be obtained accurately.

The area extracting section 24 extracts a predetermined color area of the image pickup area S.
2, an area based on preset color data is extracted, and a mask storage unit 2 described below is extracted.
5 and output as image data. The video information data input to the area extracting unit 24 is output in a well-known RGB data format. Therefore, as shown in FIG. Region extraction is performed by extracting pixels having data falling within the width based on the color data having the width.
The region extraction based on the color data is performed in addition to RGB.
May be converted into luminance, hue, and saturation, and a threshold may be provided only for hue to extract an area.
The color area extracted by the area extracting unit 24 includes:
An area having a predetermined surface color may be formed by the desk plate 5 which is an imaging object disposed at the measurement points P1, P2, P3. The material of this desk plate 5 is
When the reflectance of the surface is high, the data about the hue of the video information output in the imaging direction by the television camera 1 changes, and therefore, it is optimal that the surface gloss is eliminated and the reflection surface is close to perfect diffusion.

The mask storage unit 25 sets and stores the area extracted by the area extraction unit 24 as an illuminance measurement mask. For example, a two-dimensional memory constituted by a RAM (random access memory) as an image memory It is. By operating the ten-key switch of the setting input unit 23 in accordance with guidance displayed on a display device such as a monitor television (not shown) in the mask storage unit 25,
As shown in FIG. 4C, extracted area screen data output from the area extracting unit 24 is stored. The extracted region image data stored in the mask storage unit is always used when the illumination control device is used, and needs to be corrected only when the arrangement in the imaging region S is changed after the storage operation.

The illumination control unit 3 generates and outputs a predetermined illumination control signal based on the output from the illuminance measurement unit 2. For example, the illumination control unit 3 converts a transmission signal of the time division multiplex transmission system into two balanced control signal lines L2. , Each of which has an address, receives this transmission signal, and outputs it to a lighting fixture 4 that performs lighting control such as dimming according to a lighting control signal of its own unique address.

Next, a description will be given of the luminance / illuminance conversion of the arithmetic unit 21 for performing the illuminance calculation of the imaging area based on the luminance information of the video information output from the television camera 1 in the above-described illumination control device.

First, at the time of installation of the illumination control device, the ten-key switch which is the setting input part 23 provided in the illuminance measuring part 2 is used to mount the television camera 1 from the desk D at the mounting height h, the mounting angle, The tilt angle θ is input. The computing unit 21 calculates the measurement points P from the TV camera 1 based on the input data of the mounting height h and the tilt angle θ of the camera.
The distances to 1, P2, P3... Are calculated. Next, the actual illuminance at the measurement point is compared with the luminance data of the television camera 1. That is, the object to be measured is the desk D installed in the office, and the illuminance by the lighting fixture 4 is first set to the desk D.
Above, the illuminance L1 is measured by the illuminometer, and the luminance data V1 of the area of the desk D stored in the digital video storage unit 22 is extracted. The luminance data V1 is multiplied by a coefficient inversely proportional to the square of the distance in the distance data to the measurement point obtained above. The luminance data depends on the condition of the number of bits of the analog-to-digital conversion. For example, the luminance data is extracted in 8-bit data in 0 to 255 steps based on the number of steps. Next, since it is considered that the appropriate illuminance on the desk D is generally desired to be about 500 lux,
The illumination control unit 3 increases the brightness level of the illumination load 41 and measures the luminance data V2 of the area of the desk D in the digital video storage unit 22 when the illuminance on the desk D becomes 500 lux. Then, as shown in FIG. 3, the above (V1,
L1) and (V2, 500) are plotted on a graph, interpolated by a straight line connecting the two points, and the luminance data is converted to illuminance by the straight line.

Needless to say, the accuracy of the data interpolation is improved by performing the data interpolation at more points. In the case of the multipoint, the interpolation curve may be obtained by least square approximation. Also, the point of V2 where the illuminance is 500 lux is 255
If the value exceeds or is extremely close, the manual aperture adjustment function of the television camera 1 is adjusted so that V2 becomes an appropriate value of about 230. Of course, 500 lux itself, which is an appropriate illuminance, is not limited to the value alone, and may be set freely according to the user's preference.
Further, the above-described conversion formula of the straight line or curve of the luminance / illuminance conversion may be obtained only when the lighting control device is installed.
Thereafter, the above conversion formula can be stored in the storage means and used for a long time.

In the above-described illumination control device, in actual use, the arithmetic unit 21 of the illuminance measurement unit 2 is output from the digital image storage unit 22 with the luminance data obtained by the video output from the television camera 1. The illuminance obtained by converting the luminance data based on the video output from the television camera 1 by the above conversion formula is compared with a preset appropriate illuminance, and an illumination control signal corresponding to the difference is output to the illumination control unit 3. Lighting equipment 4
Is controlled. The control of the luminaire 4 is an effective feedback control with respect to a change in external light or a deterioration of a lighting load, and the illuminance in the room can be always kept close to an appropriate illuminance. The measurement / control interval may be determined in consideration of the speed of change of external light or the like, and a sufficient effect can be obtained even with an interval of minutes. Also, there is sufficient time for the above-described conversion calculation, and the C /
The PU may have a low speed.

In addition, the above-mentioned lighting control device sets a plurality of the above-mentioned measurement points and controls the positions of the lighting fixtures 4, 4. In addition to the correspondence between the positions of the measurement points P1, P2, P3, and the like, the correspondence of which lighting fixture is to be dimmed to control the illuminance of which measurement point is set in advance. The illuminance measurement at each measurement point is performed in the area of the desk plate 5 which is extracted by the area extracting unit 24 and stored in the mask storage unit 25. In this illuminance measurement, the image information of the digital image storage unit 22 and the mask storage unit 25 are read simultaneously, and the mask storage unit 25
AND operation of the extraction area screen data according to the above is performed to extract the measurement area. In the measurement area extraction processing, the color image processing for each illuminance measurement is not required, and the processing can be simplified to increase the speed. Further, by extracting the color data based on the color of the desk plate 5 and measuring the illuminance only in the area, even if there are obstacles such as documents on the desk plate 5 on the desk D, the Is excluded from the illuminance measurement region, the illuminance of the remaining true illuminance measurement object surface can be measured, and the accuracy of illuminance measurement can be improved.

The illuminance measuring unit 2 is operated by an arithmetic unit 21
As shown in FIG. 5, placed on the desk plate 5,
For example, the absence display plate 51, which is a second object to be imaged, on which the different colors are arranged on the front and back sides, outputs an illumination control signal such as dimming or extinguishing based on a change in a different surface color. That is, in order to indicate absence when a person leaves the desk, the absence display plate 51 has the same surface color as the surface color of the desk plate 5 and a different color from the front surface of the desk plate 5 on the back surface. The region extracting unit 24 has two colors, that is, the surface color of the desk plate 5 and the color of the back surface of the absence display plate 51. Then, when the color of the back surface of the absence display plate 51 is extracted and detected, an output to that effect is output to the calculation unit 21. Arithmetic unit 2
When the signal is input, 1 judges that a person has left the seat and performs control such as lowering the illuminance of the place. The absence display plate 51 may be plate-shaped, and there is no limitation on the material. However, it is preferable that the absence display plate 51 be a diffusion surface in order to accurately perform color measurement.

According to the illumination control device described above, the luminance information from the TV camera 1 is converted into the illuminance information at the measurement point. Accordingly, the illuminance on a desk or the like can be kept constant even when external light changes. In addition, since the illuminance calculation result is based on the luminance data of the measurement point in the area extracted by the illuminance measurement mask, the illuminance data is based on the predetermined area surface, so that more accurate illuminance can be measured at high speed. In addition, since the illuminance at the measurement point is measured with a predetermined surface color of the desk plate 5, an object that diffuses and reflects the desk plate 5 is selected to determine the angle of imaging with the measurement point. The illuminance data is not affected by the influence of, and the illuminance can be measured more accurately. In addition, since the lighting control unit 3 can control the lighting fixture by changing the surface color of the desk plate 5 or the absence display plate 51, the user's intention can be directly transmitted to the lighting control device. Thus, the lighting device 4 can be easily controlled.

In the above description, it is assumed that the illumination control device has a region extracting means and a mask storing means,
Furthermore, although an example in which an object to be imaged having a predetermined surface color is arranged at a measurement point has been described above, the present invention is not limited to this, and there is no area extraction unit and no mask storage unit. It may be one that does not have an object to be imaged. In the above-described illumination control, only the conversion of the luminance data corresponding to the distance data may be performed, and the illumination control may be directly performed based on the converted luminance data.

[0038]

According to the illumination control device of the present invention, the luminance information obtained by the imaging means is corrected by the distance to the measurement point. , The lighting load can be easily controlled according to the change in the illuminance on the desk.

In the illumination control device according to the second aspect, in addition to the effect of the first aspect, the illuminance calculation result is based on the luminance data of the measurement point in the area extracted by the illuminance measurement mask. In addition, the illuminance data is based on the predetermined area plane, and more accurate illuminance can be measured.

According to a third aspect of the present invention, in addition to the effects of the first or second aspect, the illumination control device measures the illuminance of the object at a measurement point with a predetermined surface color. Therefore, by selecting an object that diffusely reflects the object to be imaged, the illuminance data is not affected by the influence of the angle of imaging with the measurement point and the like, and the illuminance can be measured more accurately.

According to the illumination control device of the fourth aspect, in addition to the effect of the third aspect, the illumination control means can control the illumination device by changing the surface color of the object to be imaged. The user's will can be transmitted directly to the lighting control device,
Thus, the lighting equipment can be easily controlled.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a lighting control device of the present invention.

FIG. 2 is an explanatory diagram of a distance calculation of the lighting control device shown in FIG.

FIG. 3 is an explanatory diagram of luminance / illuminance conversion of the illumination control device shown in FIG. 1;

FIG. 4 is an explanatory diagram of an operation of a mask storage unit of the illumination control device shown in FIG.

5 is an explanatory diagram of control by a change in the surface color of an object to be imaged by the illumination control device shown in FIG. 1;

FIG. 6 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Television camera (imaging means) 2 Illuminance measurement part (illuminance measurement) 21 Calculation part (luminance / illuminance conversion means) 22 Digital video storage part (storage means) 23 Setting input part (attachment condition input means) 24 Area extraction part (area Extraction unit) 25 Mask storage unit (mask storage unit) 3 Illumination control unit (illumination control unit) 4 Illumination equipment 41 Illumination load 5 Desk plate (imaging object) 51 Absence display plate (imaging object) S Imaging area P1, P2 , P3 measurement point

Claims (4)

[Claims] An image pickup means such as a television camera for outputting a video signal, a storage means for storing video information, and a luminance / light quantity calculation section for calculating an illuminance of an imaging area based on luminance information of the video information stored in the storage means. An illuminance measurement unit having an illuminance conversion unit, an illumination control unit for generating and outputting a predetermined illumination control signal based on an output from the illuminance measurement unit, and an illumination control signal input to control an illumination load to control a predetermined area. A lighting control device comprising: a lighting device for illuminating; and mounting condition input means for inputting a mounting condition of a mounting height and a mounting angle of the imaging means, and wherein the luminance / illuminance conversion means performs the processing based on the mounting condition information. An illumination control device, wherein a distance to a measurement point in an imaging area by an imaging unit is calculated, luminance information is corrected based on the calculation result, and the illuminance is calculated. 2. The image processing apparatus according to claim 1, wherein the illuminance measurement unit includes a region extraction unit that extracts a predetermined color region of the imaging region, and a mask storage unit that sets and stores the region extracted by the region extraction unit as an illuminance measurement mask. 2. The illumination control device according to claim 1, wherein said luminance / illuminance conversion means calculates said illuminance using video information in an illuminance measurement mask. 3. The illumination control device according to claim 1, wherein an object to be imaged having a predetermined surface color is disposed at the measurement point. 4. The illumination control device according to claim 3, wherein said region extracting means is capable of extracting at least two different surface colors of said object to be imaged.