KR20110015162A - Control method of surveillance camera and surveillance camera employing same - Google Patents

Abstract

The method according to the invention is a control method of a surveillance camera that generates a live-view video signal by imaging, comprising steps (a) and (b). In step (a), it is determined whether or not motion has occurred in the live-view image. In step (b), when a motion occurs in the live-view image, automatic focusing, automatic exposure dose adjustment, and automatic white balancing are performed on the area after the movement.

CCTV, Security Camera

Description

Method for detecting disturbance of monitoring camera, and monitoring camera adopting the same}

The present invention relates to a method for controlling a surveillance camera and a surveillance camera employing the same, and more particularly, to a surveillance camera controlling method for generating a live-view video signal by shooting and employing the same. It is about a surveillance camera.

Surveillance cameras generate live-view video signals by imaging. Surveillance cameras also transmit live-view video signals to the computers while communicating with the computers as monitoring devices.

Such surveillance cameras, as is well known, perform 3A, that is, auto focusing, auto exposure dose adjustment and auto white balancing.

However, there are the following problems as the 3A is performed on the entire image.

First, since the effect of 3A is inferior, the reproducibility of the image displayed on the computer as the monitoring device is lowered.

Second, since the execution time of 3A becomes long, there is a time when a computer as a monitoring device cannot display an image clearly.

Third, the specificity of the surveillance function cannot be enhanced.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for controlling a surveillance camera and a surveillance camera employing the same that can enhance the reproducibility and sharpness of an image displayed on a computer as a monitoring apparatus, and can enhance the specificity of a surveillance function.

The method of the present invention is a control method of a surveillance camera that generates a live-view video signal by imaging, comprising steps (a) and (b).

In step (a), it is determined whether or not motion has occurred in the live-view image.

In step (b), when a motion occurs in the live-view image, automatic focusing, automatic exposure dose adjustment, and automatic white balancing are performed on the area after the movement.

The surveillance camera of the present invention includes a main control unit and generates a live-view video signal by photographing. Here, the control method used in the main control unit includes the steps (a) and (b).

The control method of the surveillance camera of the present invention and the surveillance camera employing the same detect a motion according to a well-known motion detection algorithm, and perform 3A, that is, automatic focusing, automatic exposure dose adjustment, and automatic white balancing for a motion region. .

That is, since 3A is performed only for the motion region, not the entire region, the following effects can be obtained.

First, since the effect of 3A is enhanced, the reproducibility of the image displayed on the computer as the monitoring device is increased.

Second, since the execution time of 3A is shortened, there is no time for the computer as a monitoring device to not display an image clearly.

Third, in the surveillance camera where the moving area is an important shooting target, since the moving area is more reproducible and clear than other areas, the specificity of the monitoring function can be enhanced.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 shows a surveillance system to which surveillance cameras 1a, 1b and 1c are applied according to a first embodiment of the present invention.

Referring to FIG. 1, each of the surveillance cameras 1a, 1b and 1c generates a live-view video signal by photographing.

In addition, each of the surveillance cameras 1a, 1b, 1c communicates with the computers 3a, 3b, 3c as monitoring devices via a communication channel D _COM , and is live- _viewed through the video signal channel S _VID . The video signal of the (Live-view) is transmitted to the computers 3a, 3b, and 3c.

Here, each of the surveillance cameras 1a, 1b, 1c detects motion in accordance with a well-known motion detection algorithm, and performs 3A, that is, auto focusing, auto exposure dose adjustment, and auto white balancing on the motion area.

That is, since 3A is performed only for the motion region, not the entire region, the following effects can be obtained.

First, since the effect of 3A is enhanced, the reproducibility of the image displayed by the computers 3a, 3b, 3c as the monitoring device is increased.

Second, since the execution time of 3A is shortened, there is no time for the computer 3a, 3b, 3c as a monitoring device not to display an image clearly.

Third, in the surveillance cameras 1a, 1b, and 1c in which the motion area is an important shooting target, the motion area is more reproducible and clear than other areas, so that the specificity of the monitoring function can be enhanced.

Related contents are described in detail with reference to FIGS. 2 to 11.

FIG. 2 shows the internal configuration of any surveillance camera 1a or 1b or 1c of FIG. 1.

3, the surveillance camera in the surveillance system according to the present invention includes an optical system (OPS), a photoelectric conversion unit (OEC), a Correlation Double Sampler and Analog-to-Digital Converter (101), a timing circuit ( 102, a digital signal processor (DSP) as a controller, a video-signal generator 108, an aperture motor (M _A ), a zoom motor (M _Z ), a focus motor (M _F ), a filter And a motor M _D , a driver 110, and a communication interface 112.

The optical system OPS including the lens unit 301 and the filter unit 302 optically processes light from a subject.

The lens unit 301 of the optical system OPS includes a zoom lens ZL and a focus lens FL. In the filter unit 302 of the optical system OPS, an optical low pass filter (OLPF) used in the night mode of operation removes optical noise of high frequency content. Infra-Red cut filter (IRF) used in daytime operation mode cuts off the infrared component of incident light.

A photoelectric conversion unit (OEC) of a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) converts light from an optical system (OPS) into an electrical analog signal. Here, the digital signal processor 107 as the main controller controls the timing circuit 102 to control the operations of the photoelectric conversion unit OEC and the Correlation Double Sampler and Analog-to-Digital Converter 101. .

The CDS-ADC 101 processes the analog video signal from the photoelectric converter (OEC), removes the high frequency noise, adjusts the amplitude, and converts the digital video data. This digital image data is input to the digital signal processor 107.

The digital signal processor 107 performing overall control processes the digital signal from the CDS-ADC element 101 to generate digital image data classified into luminance and chroma signals.

The video-signal generator 108 converts digital image data from the digital signal processor 107 into a video signal S _VID which is an analog image signal.

The digital signal processor 107 communicates with the digital video recorder (DVR, 2 of FIG. 1) as a recording device via the communication interface 112 and the communication channel (D _{COM in} FIG. 1), and the video signal channel (S _VID ). The video signal from the video-signal generator 108 is transmitted to the digital video recorder 2 through the digital video recorder 2.

The digital signal processor 107 controls the driving unit 110 to drive the aperture motor M _A , the zoom motor M _Z , the focus motor M _F , and the filter motor M _D. The aperture motor M _A drives the aperture (not shown), the zoom motor M _Z drives the zoom lens ZL, and the focus motor M _F drives the focus lens FL. The filter motor M _D drives the optical low pass filter OLPF and the infrared cut filter IRF in the filter unit 302.

Here, when a motion occurs in the live-view image, the digital signal processor 107 as the main controller performs 3A, that is, auto focusing, auto exposure dose adjustment, and auto white balancing on the region after the movement. do. Related contents are described with reference to FIGS. 3 to 11.

FIG. 3 shows an operation algorithm of the digital signal processor 107 as the main controller of FIG. 2.

4 to 6 show a single motion region.

Referring to FIG. 4. When the object on the left in the entire image 41 moves to the right, the digital signal processor 107 as the main controller sets the right region 412 after the movement as the movement region, not the left region 411 before the movement.

Referring to FIG. 5, when an object enters from the outside of the entire image 51, the digital signal processor 107 sets the object region 511 after the entry as a movement region.

Referring to FIG. 6, when an object in the entire image 61 is moved outward, the digital signal processor 107 sets the original object area 611 as the movement area.

7 to 9 show a plurality of movement regions.

Referring to FIG. When objects on the right side of the entire image 71 move to the left, the digital signal processor 107 sets the left regions 712 and 714 after the movement as the movement regions, not the right regions 711 and 713 before the movement.

Referring to FIG. 8, when objects enter from the outside of the entire image 81, the digital signal processor 107 sets the object regions 812 and 812 after entering as motion regions.

Referring to FIG. 9, when objects in the entire image 91 move outward, the digital signal processor 107 sets the object regions 911 and 912 which are the original movement regions.

An operation algorithm of the digital signal processor 107 as the main controller of FIG. 2 will be described with reference to FIGS. 3 to 9 as follows.

First, the digital signal processor 107 determines whether motion is detected according to a well-known motion detection algorithm (step S301).

Next, if motion is detected, the digital signal processor 107 determines whether it is a periodic motion (step S302).

Next, if it is not periodic movement, the digital signal processor 107 determines whether or not the holding time after the movement is longer than the lower limit time (step S303).

Next, if the holding time after the movement is longer than the lower limit time, the digital signal processor 107 determines the regions 412, 511, 611, 712, 714, 811, 812, 911, and 912 after the movement as the movement region (step S304).

For reference, the steps S302 and S303 are functions of a motion filter.

Next, the digital signal processor 107 determines whether or not a plurality of movement regions have been generated (step S305).

If a plurality of movement regions are not generated in step S305 and a single movement region is generated, the digital signal processor 107 performs 3A, that is, auto focusing, automatic exposure dose adjustment, and automatic white balancing for the single movement region (step S306). ).

If a plurality of movement regions are generated in step S305, at least one movement region is selected by the manual mode or the automatic mode, and 3A, that is, automatic focusing, automatic exposure dose adjustment, and automatic white balancing are performed on the selected movement region (step S307 to S309).

All the above steps are repeatedly performed until the end signal is generated (step S310).

10 shows a detailed algorithm of the manual mode (step S308) of FIG.

The detailed algorithm of the manual mode (step S308) of FIG. 3 will be described with reference to FIGS. 7 to 10 as follows.

First, the digital signal processor 107 communicates with the computers 3a, 3b, 3c as the monitoring device via the communication channel (D _{COM in} FIG. 1), and the plurality of motion regions via the video signal channel S _VID . A video signal of an image in which 712,714 or 811,812 or 911,912 is blinking is transmitted to the computers 3a, 3b, and 3c (step S101).

Next, when a selection signal of one movement area is input from the user (step S102), 3A, that is, automatic focusing, automatic exposure dose adjustment, and automatic white balancing are performed on the selected movement area (step S103).

FIG. 11 shows a detailed algorithm of the automatic mode (step S309) of FIG.

A detailed algorithm of the automatic mode (step S309) of FIG. 3 will be described with reference to FIGS. 7 to 9 and 11 as follows.

First, the digital signal processor 107 determines what detailed mode is set by the user (step S111).

When the detail mode is "size", the digital signal processor 107 finds the movement region 714 or 812 or 912 having the largest area among the plurality of movement regions 712,714 or 811,812 or 911,912 (step S112). .

Further, the digital signal processor 107 performs 3A, that is, auto focusing, auto exposure dose adjustment, and auto white balancing on the movement area 714 or 812 or 912 having the largest area (step S113).

When the detail mode is "average", the digital signal processor 107 performs 3A, that is, auto focusing, auto exposure dose adjustment, and auto white balancing on all the movement regions 712,714 or 811,812 or 911,912 (step S114). .

When the detail mode is the "hold time", the digital signal processor 107 finds the motion area having the longest holding time among the plurality of motion areas 712,714 or 811,812 or 911,912 (step S115).

In addition, the digital signal processor 107 performs 3A, that is, automatic focusing, automatic exposure dose adjustment, and automatic white balancing, on the movement region having the longest holding time (step S116).

As described above, the control method of the surveillance camera according to the present invention and the surveillance camera employing the same, detect the movement according to a well-known motion detection algorithm, 3A for the movement area, that is, automatic focusing, automatic exposure dose adjustment and Perform automatic white balancing. That is, since 3A is performed only for the motion region, not the entire region, the following effects can be obtained.

First, since the effect of 3A is enhanced, the reproducibility of the image displayed on the computer as the monitoring device is increased.

Second, since the execution time of 3A is shortened, there is no time for the computer as a monitoring device to not display an image clearly.

Third, in the surveillance camera where the moving area is an important shooting target, since the moving area is more reproducible and clear than other areas, the specificity of the monitoring function can be enhanced.

It can be used not only for surveillance cameras but also for all cameras capable of shooting video.

1 is a block diagram illustrating a surveillance system to which surveillance cameras according to a first exemplary embodiment of the present invention are applied.

FIG. 2 is a block diagram illustrating an internal configuration of any one surveillance camera of FIG. 1.

FIG. 3 is a flowchart illustrating an operation algorithm of the digital signal processor as the main controller of FIG. 2.

4 to 6 show a single motion region.

7 to 9 are diagrams illustrating a plurality of movement regions.

10 is a flowchart showing a detailed algorithm of the manual mode of FIG.

FIG. 11 is a flowchart showing a detailed algorithm of the automatic mode of FIG. 3.

<Explanation of symbols for the main parts of the drawings>

1a, 1b, 1c ... surveillance cameras, 3a, 3b, 3c ... computers,

OPS ... optical system, OEC ... photoelectric conversion unit,

101 ... CDS-ADC, 102 ... timing circuit,

107 digital signal processor, 108 video signal generator,

110 ... Drive, 112 ... Communication interface.

Claims (9)

In the control method of the surveillance camera that generates a live-view video signal by shooting, (a) determining whether motion has occurred in an image of a live-view; And (b) When a motion occurs in a live-view image, a method of controlling a surveillance camera including performing auto focusing, automatic exposure dose adjustment, and automatic white balancing on a region after the movement. The method of claim 1, wherein step (a) If motion is detected, determine whether it is a periodic movement; If it is not a periodic movement, determining whether the holding time after the movement is longer than the lower limit time; And And if the holding time after the movement is longer than the lower limit time, determining the area after the movement as the movement region. The method of claim 2, wherein step (b) (b1) determine whether a plurality of movement regions have been generated; And (b2) controlling a surveillance camera including performing auto focusing, automatic exposure dose adjustment, and automatic white balancing on the single movement region when a plurality of movement regions are not generated and a single movement region is generated. The method of claim 3, wherein step (b) (b3) controlling a surveillance camera further comprising selecting at least one movement region by a manual mode or an automatic mode when a plurality of movement regions are generated, and performing automatic focusing, automatic exposure dose adjustment, and automatic white balancing on the selected movement region. Way. The method of claim 4, wherein the manual mode in step (b3), Transmitting a video signal of an image in which the plurality of movement regions are blinking to a monitoring device; And When the selection signal of any one movement area is input from the user, the method of controlling the surveillance camera, including performing auto focusing, automatic exposure dose adjustment, and automatic white balancing for the selected movement area. The method of claim 4, wherein the automatic mode in step (b3), Finding a motion area having the largest area among the plurality of motion areas; And A method of controlling a surveillance camera, including performing auto focusing, auto exposure dose adjustment, and auto white balancing on a moving area having the largest area. The method of claim 4, wherein the automatic mode in step (b3), A method for controlling a surveillance camera, including performing auto focusing, auto exposure adjustment, and auto white balancing on all moving areas. The method of claim 4, wherein the automatic mode in step (b3), Finding a movement region having the longest holding time among the plurality of movement regions; And A method of controlling a surveillance camera, including performing auto focusing, automatic exposure adjustment, and automatic white balancing on a moving region having the longest holding time. In the surveillance camera comprising a main control, for generating a live-view video signal by shooting, The control method used in the main control unit, (a) determining whether motion has occurred in the image of a live-view; And (b) When a movement occurs in a live-view image, the surveillance camera including performing auto focusing, automatic exposure dose adjustment, and automatic white balancing on the area after the movement.

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