JP2002290827A - Monitor camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitor camera which automatically select a correction area of video according to the displacement of backlight. SOLUTION: The monitor camera has an image pickup element 2 which converts a subject image captured by a lens 1 into a video signal and a backlight correction processing part 3 which controls the stop of the lens 1 so that the luminance of one area specified for video on a picture plane based upon the video signal is suppressed and is equipped with a CPU 6 which stores a plurality of kinds of area formed by dividing the video on the picture plane in a ROM 5 and selects and specifies one of the areas to the backlight correction processing part 3 according to image pickup conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surveillance camera for automatically correcting an image which is difficult to see due to backlight.

[0002]

2. Description of the Related Art FIG. 6 is a block diagram showing a schematic configuration of a conventional surveillance camera. The image sensor 2 (CCD) of the surveillance camera shown in FIG. 1 converts a subject captured by the lens 1 into a video signal 100, and the backlight correction processing unit 3
When the brightness of the image based on the image signal 100 from the image exceeds a threshold value in a preset area, the aperture of the lens 1 is controlled 103 so that the image brightness in the area is equal to or less than the threshold value, and the image due to backlight is corrected. , Corrected video signal 1
01 is output. The video signal generation unit 4 includes the backlight correction processing unit 3
Video output 10 based on corrected video signal 101 from
Generate 2.

[0003]

In this conventional surveillance camera, since the area of an image to be corrected by backlight is set in advance as described above, the direction of light (backlight) entering the lens due to some factor is determined by the camera. When it is displaced when viewed from above, the position of the area has to be reset.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a surveillance camera that automatically selects a correction area in an image according to a backlight displacement.

[0005]

(1) A surveillance camera according to the present invention comprises a lens, an image sensor for converting a subject captured by the lens into a video signal, and a video on a screen based on the video signal. A backlight compensation processing unit for controlling the aperture of the lens so as to suppress the luminance on one designated area, and has a plurality of types of areas formed by dividing the video on the screen. An area discriminating means for selecting one area from a plurality of types of areas in accordance with an imaging condition and designating the selected area to the backlight correction processing unit is provided.

(2) In the surveillance camera according to the present invention, in (1), the area discriminating means compares the light amount of the image based on the image signal with a preset threshold value and recognizes the light amount exceeding the threshold value. At this time, the area of the light amount is determined, the area is selected from the plurality of types, and designated to the backlight correction processing unit.

(3) The surveillance camera according to the present invention according to (1), further comprising a timer, wherein the area discriminating means changes the area set in advance when the time of the timer reaches a predetermined time into a plurality of types of areas. And designate it to the backlight correction processing unit.

(4) The surveillance camera according to (1), further comprising a sensor, wherein the area discriminating means selects a preset area from a plurality of types of areas when a signal from the sensor is detected. , The backlight correction processing unit.

(5) The surveillance camera according to the present invention is provided with the microphone according to (1) above, wherein the area discriminating means selects a preset area from a plurality of types of areas when detecting a signal from the microphone. , The backlight correction processing unit.

[0010]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIGS. The same or corresponding parts as in the conventional example described with reference to FIG. Embodiment 1 FIG. FIG. 1 is a block diagram showing a schematic configuration of the surveillance camera according to Embodiment 1 of the present invention. A plurality of types of areas formed by dividing the video on the screen are stored in the ROM 5 shown in FIG. The plurality of types of areas are a set of areas in which the video on the screen is divided into a number of blocks (15 × 15), and the plurality of blocks are formed into one area.

[0011] The CPU 6 is stored in the ROM 5 according to imaging conditions, for example, changes in the amount of light in day and night images, time by a timer, signals from various sensors for detecting opening of the door, signals from a microphone, and the like. One area is selected from a plurality of types of areas, and the selected area is specified to the backlight correction processing unit 3.

As described above, one area is selected from a plurality of types of areas in accordance with the imaging conditions, and the area is designated in the backlight correction processing unit. Therefore, backlight correction according to a plurality of conditions is performed. Can be.

Embodiment 2 FIG. FIG. 2 is a block diagram showing a schematic configuration of the surveillance camera according to Embodiment 2 of the present invention. In the second embodiment, an area for correcting an image is selected in accordance with, for example, the direction of sunlight from sunrise to sunset or the displacement of backlight at night due to the influence of illumination.

The CPU 6 shown in FIG. 2 sets in advance a threshold value for determining the intensity of the light amount, compares the light amount of the image based on the image signal from the image sensor 2 with the threshold value, and recognizes the light amount exceeding the threshold value. Then, the area of the light amount is determined. Then, by accessing the ROM 5, the corresponding area is selected from a plurality of types of areas, and is designated to the backlight correction processing unit 3.

As described above, in the second embodiment, one area is selected in accordance with the direction of backlight, which changes depending on changes in the surrounding environment. There is an effect that a clear image can be obtained.

Embodiment 3 FIG. 3 is a block diagram showing a schematic configuration of a surveillance camera according to Embodiment 3 of the present invention. In the third embodiment, an area for correcting an image is selected each time a predetermined time is reached.

The CPU 6 in the figure has, for example, data of a sunrise time, hourly or every two hours from this time, and an image correction area set corresponding to each time. , The time measured by the timer 7 is monitored, and when the time reaches a predetermined time, the same area as the area set corresponding to the time is stored in the ROM.
5 and is specified to the backlight correction processing unit 3.

As described above, in the third embodiment, the area for correcting the image is changed at each preset time, so that the correction of the image by the backlight is effective, and a clear image can always be provided. .

Embodiment 4 FIG. 4 is a block diagram showing a schematic configuration of a surveillance camera according to Embodiment 4 of the present invention. In the fourth embodiment, an area for correcting an image is selected when a signal from a sensor 8 provided outside is detected.

The CPU 6 to which the sensor 8 is connected usually designates an area in which the entire screen can be clearly seen to the backlight correction processing unit 3, and for example, detects a signal from the sensor 8 for detecting opening of the door. At this time, an area where the image centered on the door is sharpened is read out from the ROM 5 and switched to the area designated by the backlight correction processing unit 3.

As described above, in the fourth embodiment, when the detection signal of the sensor 8 is detected, the area is switched to an area where the image centered on the door becomes clear.
The image of the intruder from the door can be clearly displayed without being affected by the backlight.

In the fourth embodiment, one sensor 8
However, the present invention is not limited to this, and a plurality of sensors may be used to switch the correction area when any one of the sensors operates. Further, instead of this sensor, a vibration sensor or the like for detecting breakage of the window glass may be used.

Embodiment 5 FIG. 5 is a block diagram showing a schematic configuration of a surveillance camera according to Embodiment 5 of the present invention. In the fifth embodiment, when sound or noise is detected, the area to be corrected is switched.
The microphone 9 in the figure is installed inside a camera (not shown), and the CPU 6 designates an area in which the entire screen can be normally seen to the backlight correction processing unit 3 as described above. Is input, the area where the image at the center of the screen becomes sharper is read out from the ROM 5 and switched to the area designated by the backlight correction processor 3.

As described above, in the fifth embodiment, when the sound is input through the microphone 9, the image is switched to an area where the image in the center of the screen becomes clear. It can be projected clearly without receiving.

[0025]

As described above, according to the present invention, one area is selected from a plurality of types of areas according to the imaging conditions and the area is designated in the backlight correction processing unit. Backlight correction according to the above.

According to the present invention, the light amount of the image based on the image signal is compared with a preset threshold value, and when the light amount exceeding the threshold value is recognized, the area of the light amount is determined and a plurality of types of areas are determined. , And is designated in the backlight correction processing unit, so that there is an effect that a clearer image can always be obtained as compared with the related art in which the area for correcting the image is fixed.

Further, according to the present invention, when the time of the timer reaches a predetermined time, a preset area is selected from a plurality of types of areas and designated to the backlight correction processing unit. Correction is effective, and a clear image can always be provided.

Further, according to the present invention, when a signal from a sensor is detected, a preset area is selected from a plurality of types of areas and designated to the backlight correction processing section, so that an intruder from the door can be detected. Images can be projected clearly without being affected by backlight.

Furthermore, according to the present invention, when a signal from a microphone is detected, a preset area is selected from a plurality of types of areas and designated to the backlight correction processing unit. Can be projected clearly without being affected by backlight.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a surveillance camera according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram illustrating a schematic configuration of a surveillance camera according to Embodiment 2 of the present invention.

FIG. 3 is a block diagram illustrating a schematic configuration of a surveillance camera according to Embodiment 3 of the present invention.

FIG. 4 is a block diagram showing a schematic configuration of a surveillance camera according to Embodiment 4 of the present invention.

FIG. 5 is a block diagram showing a schematic configuration of a surveillance camera according to Embodiment 5 of the present invention.

FIG. 6 is a block diagram illustrating a schematic configuration of a conventional surveillance camera.

[Explanation of symbols]

1 lens, 2 image sensor, 3 backlight correction processing unit, 4
Video signal generator, 5 ROM, 6 CPU, 7 timer, 8 sensor, 9 microphone.

Claims (5)

[Claims] 1. A lens, an image sensor for converting a subject photographed by the lens into a video signal, and suppressing luminance on one area designated for a video on a screen based on the video signal. A backlight correction processing unit for controlling the aperture of the lens, comprising a plurality of types of areas formed by dividing an image on a screen, from a plurality of types of areas according to imaging conditions A surveillance camera comprising an area discriminating means for selecting one area and designating the selected area in the backlight correction processing section. 2. The area discriminating means compares a light amount of an image based on an image signal with a preset threshold value, and when recognizing a light amount exceeding the threshold value, discriminates an area of the light amount and determines the plurality of types. The surveillance camera according to claim 1, wherein the surveillance camera is selected from the following areas and designated to the backlight correction processing unit. 3. An apparatus according to claim 1, further comprising a timer,
The surveillance camera according to claim 1, wherein when the time of the timer reaches a predetermined time, a preset area is selected from the plurality of types of areas and designated to the backlight correction processing unit. 4. An apparatus according to claim 1, further comprising a sensor, wherein:
The surveillance camera according to claim 1, wherein when a signal from the sensor is detected, a preset area is selected from the plurality of types of areas and designated to the backlight correction processing unit. 5. A microphone comprising: a microphone;
The surveillance camera according to claim 1, wherein when a signal from the microphone is detected, a preset area is selected from the plurality of types of areas and designated to the backlight correction processing unit.