KR20150101313A - Apparatus and method for processing image - Google Patents

Abstract

The present invention relates to an image processing apparatus which controls the amount of data processed for the image compression depending on a driving speed of a pan motor or a tilt motor in a camera to reduce a compression rate for an unrecognizable image, thereby improving the efficiency of image compressive process, and to a method thereof. According to the present invention, the image processing apparatus comprises: a camera for photographing a monitoring area; a compression unit for compressing image frames photographed by the camera into the predetermined number of image frames; a pan/tilt motor for horizontally and vertically rotating the camera; a motor control unit for controlling the driving of the pan/tilt motor, and calculating the driving speed when the pan/tilt motor moves according to a monitoring mode; and a control unit for controlling the compression unit to compress the number of image frames photographed by the camera to be smaller than the predetermined number of the image frames when the driving speed is greater than or equal to the reference speed by comparing the driving speed received from the motor control unit with the predetermined reference speed.

Description

[0001] APPARATUS AND METHOD FOR PROCESSING IMAGE [0002]

The present invention relates to an image processing apparatus and method.

Korean Patent Laid-Open Publication No. 1997-57795 discloses a variable-data-frame-number variable control apparatus, which variably adjusts the number of image frames subjected to compression processing within 30 frames per second, The amount of image compression data generated is proportional to the amount of image compression data generated. That is, when the magnitude of the quantization coefficient value is equal to or greater than the set quantization coefficient value, a predetermined number of input image frames are put into a high impedance state and the compression processing section skips the data without compression processing. It is possible to adjust the amount of compressed data accumulated according to the transmission speed, thereby preventing the subsequent inefficient image compression and also preventing the loss of the compressed video data stream, thereby improving the image quality of the reconstructed image and improving the reliability of the entire system .

The method of controlling the number of frames of the compressed image data variably controls the number of image frames compressed by using the input image data and the network environment (transmission speed, etc.) variables. In the case of a PTZ camera The image compression efficiency is very low. This is because all of the image data is subject to compression in the case of an image captured while moving with a PTZ camera.

The image compression data technique compares the current frame with the previous frame to find only the changed data and compress the data, and controls the number of image frames compressed according to the surrounding environment (network speed, etc.). However, when a subject that captures an image moves, such as a PTZ camera, the entire data in the frame moves, and the whole is subject to compression, which results in a problem that the image compression efficiency is low.

Korean Patent Publication No. 1997-57795

The technical problem to be solved by the present invention is to adjust the amount of data processed in the image compression according to the driving speed of the fan motor or the tilt motor in the PTZ camera, thereby reducing the compression rate for the unidentifiable image, The present invention provides an image processing apparatus capable of improving image quality.

An image processing apparatus according to an embodiment of the present invention includes a camera for photographing a surveillance region; A compression unit for compressing the image frames photographed by the camera with a predetermined number of image frames; A pan / tilt motor for horizontally and vertically rotating the camera; A motor control unit for controlling driving of the pan / tilt motor and calculating a driving speed at the time of moving the pan / tilt motor according to a monitoring mode; And a control unit that compares the driving speed received from the motor control unit with a predetermined reference speed to reduce the number of image frames photographed by the camera when the driving speed is equal to or greater than the reference speed, And a control unit for controlling the compression unit.

The camera operates in a preset mode in which the camera moves from a preset to a different preset among a preset plurality of presets.

The camera is operated in a manual mode in which the camera moves from an arbitrary surveillance area to another surveillance area by the user's operation.

According to another aspect of the present invention, there is provided an image processing method comprising: controlling compression processing of image frames photographed by a camera in a surveillance region with a preset number of image frames; Driving at least one of a fan motor and a tilt motor included in the camera according to a monitoring mode to move the camera; Comparing the drive speed of the motor received from at least one of the fan motor and the tilt motor with a set reference speed; And controlling the number of image frames photographed by the camera to be smaller than the set number of image frames when the driving speed is equal to or higher than the reference speed.

The step of moving the camera includes moving at least one of the fan motor and the tilt motor to move the camera when moving from a preset to another preset from among a preset plurality of presets do.

The step of moving the camera includes moving at least one of the fan motor and the tilt motor to move the camera when the user moves from a surveillance area to another surveillance area by manual operation .

As described above, according to the present invention, by adjusting the amount of data processed in the image compression according to the driving speed of the fan motor or the tilt motor in the camera, the compression rate for the unidentifiable image is reduced to improve the image compression processing efficiency .

1 is a block diagram showing a configuration of a video surveillance system having an image processing apparatus according to an embodiment of the present invention.
2 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention.
3 is a flowchart illustrating an operation of an image processing method according to an exemplary embodiment of the present invention.

Brief Description of the Drawings The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described in conjunction with the accompanying drawings. It should be understood, however, that the present invention is not limited to the embodiments set forth herein, but may be embodied in many different forms and includes all conversions, equivalents, and alternatives falling within the spirit and scope of the present invention . BRIEF DESCRIPTION OF THE DRAWINGS The above and other aspects of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. The terms first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. .

1 is a block diagram showing a configuration of a video surveillance system having an image processing apparatus according to an embodiment of the present invention. Referring to FIG. 1, the video surveillance system includes an image processing apparatus 100, a network 200, and an external control apparatus 300.

The image processing apparatus 100 is driven in accordance with a monitoring mode selected from the external control apparatus 300 through the network 200 to photograph and monitor the surveillance region and transmits the image to the external control apparatus 300 through the network 200 . The image processing apparatus 100 can perform compression processing by adjusting the compression rate of the image frame photographed in the surveillance region. Hereinafter, the detailed configuration of the image processing apparatus 100 will be described with reference to FIG.

The external control device 300 may be a device for signal processing the image transmitted from the PTZ camera 100 and displaying the image in a web page format, that is, a web viewer format. Or the external control device 300 may be a device capable of executing a web viewer or a mobile device capable of executing a mobile viewer. The external control device 300 may display an image captured by the image processing apparatus 100 through the network 200. The display means may be a touch panel and may include a liquid crystal display (LCD) An organic light emitting diode (OLED) or the like.

The external control device 300 controls the pan / tilt / zoom of the image processing apparatus 100 through the network 200. The manner in which the external control device 300 controls the pan / tilt / zoom of the image processing apparatus 100 can be classified into two modes. First, a manual mode in which a user can manually operate the image processing apparatus 100 using an input device (joystick, button, etc.), and second, a manual mode in which at least one preset is set in the image processing apparatus 100 And a preset mode in which the image processing apparatus 100 operates automatically according to a preset.

In the manual mode, when the external control apparatus 300 transmits a pan / tilt / zoom (including direction and speed) command inputted by the user to the image processing apparatus 100 through the network 200, (110 of FIG. 2) by driving the motor control unit (180 of FIG. 2) in the image processing apparatus 100 to analyze and reproduce the command. That is, the user can control the operation of the PTZ camera 110 in a desired speed and direction.

In the preset mode, when an instruction to go to a preset among a plurality of presets (up to a maximum of 255 can be preset) stored in advance in the external control apparatus 300 is transmitted to the image processing apparatus 100 through the network 200, The image processing apparatus 100 compares the current preset position value with the received preset position value and transmits the movement direction value and the previously defined velocity value to the motor control unit 180 to control the operation of the PTZ camera 110 . In the preset mode, the PTZ camera 110 usually operates at the maximum driving speed, but the user can set the driving speed differently according to the setting.

Next, an image processing apparatus 100 according to an embodiment of the present invention will be described with reference to FIG.

The image processing apparatus 100 includes a camera 110, a fan motor 120, a tilt motor 130, a motor control unit 140, a decoder 150, an image processing unit 160, an image compressing unit 170, (180), and a control unit (190).

The camera 100 is a pan / tilt / zoom (PTZ) speed dome camera capable of rotating the camera vertically and horizontally, and automatically reversing the image by a tilt 180 ° and a pan 360 °. It is a camera that makes it possible. Since the speed dome camera can designate the position to be monitored, the surveillance area of the camera is wider than that of the camera which monitors only the fixed position of the conventional camera. The camera 100 is connected to the external control device 300 by the external interface unit 180 and the monitoring function is controlled by an instruction from the external control device 300. The camera 110 is driven according to a predetermined monitoring mode selected from the external control device 300 and photographs the surveillance region. Here, the monitoring mode is a manual mode and a preset mode as described above. The camera 100 includes a lens and an imaging device. The lens includes a zoom lens ZL and a focus lens FL. The imaging device converts an optical signal sensed at the time of imaging into an electrical signal, and includes a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) device.

A fan motor 120; The PAN motor rotates the camera 110 360 degrees in the horizontal (X-axis) direction, and uses a variable stepping motor. The tilt motor 130 uses a stepping motor that rotates the camera 110 by 180 degrees in the vertical (Y-axis) direction and can vary the speed. The fan motor 120 and the tilt motor 130 of this embodiment have a speed of 360 degrees / sec or more.

        In the manual monitoring mode, the fan motor 120 and the tilt motor 130 have a speed range of about 0.01 to 120 deg / sec per second, which is convenient for a user to track a near and distant monitored object with a joystick Is the range used. In order to efficiently monitor surveillance targets at telephoto distances, the specification of the slowest speed and the minimum resolution can be an important factor in the case of these manual operations, rather than the high speed.

In the case of the preset monitoring mode, when the fan motor 120 and the tilt motor 130 move in a short time, for example, when the screen switching is fast while the movement is between the stored position 1 and the position 2, The efficiency of surveillance and the load of recording equipment are reduced.

In addition, when zooming is performed during the movement of the fan motor 120 and the tilt motor 130, the fan motor 120 and the tilt motor 130 are stored at the maximum speed If the zooming operation is performed with respect to the target object after moving to the position of the subject, the possibility of obtaining a clear screen with focus even during the zooming operation is increased.

The motor control unit 140 drives the fan motor 120 and the tilt motor 130 under the control of the control unit 190. The motor control unit 140 adjusts the rotation direction of the fan motor 120 and the tilt motor 130 and the driving speed at the time of movement according to the drive pulse and the drive control signal output from the control unit 190, The rotational direction of the motor 110, and the driving speed at the time of movement are also adjusted.

The directions of the fan motor 120 and the tilt motor 130 are determined in the camera 110 control command input from the external control unit 300 through the external interface unit 180 but the velocity values are not set to absolute values. The range of the speed varies depending on the type of the protocol (predetermined control protocol of the camera 110) input from the external control device 300 through the external interface unit 180, but the minimum value and the maximum value are determined. In the case of a manual operation command, the control unit 190 analyzes types of motors (fan motor 120 and tilt motor) to be driven according to the protocols of each protocol, (Clockwise direction, counterclockwise direction), and a driving speed value at the time of movement. At this time, in the case of the driving speed, since the range of each protocol is different, the range value of the minimum value and the maximum value is determined, so that it is converted into the manual speed value of the camera 110 according to the protocol. If the preset execution command is received, the control unit 190 divides the preset number of the preset to be executed according to the protocols of the protocol and outputs the position information value of the preset (the fan motor 120 and the tilt motor 130 ) To transmit the position values of the fan motor 120 and the tilt motor 130 and the driving speed information at the time of movement to the motor control unit 140. [

The motor control unit 140 controls the information values (the position value, the moving direction, the moving distance, and the driving speed when the fan motor 120 and the tilt motor 130) received from the control unit 190 and the condition The actual fan motor 120 and the tilt motor 130 are controlled using the current zoom magnification value, the fan angle of the fan motor 120 and the angle of the tilt motor 130, the belt gear ratio, the microstep, the manual maximum speed value, A moving distance, and the like, to the fan motor 120 and the tilt motor 130, as shown in FIG. In the case of manual operation command, the drive direction and the drive speed value (minimum drive speed to manual maximum speed value) at the time of movement are transmitted to the motor to be driven by the PWM signal. In the case of the preset execution command, the movement direction and the maximum speed value are transmitted to the motor to be driven with the PWM signal.

The control unit 190 transmits the information from the motor control unit 140 to the image compression unit 170. The control unit 190 controls the type of the currently driven motor, the driving direction (whether the screen is right or left), the driving speed degree / sec). Here, the driving speed is defined as a moving angle per degree (sec / sec). (RPM), RPS (rotation speed per second), PPS (pulse movement distance per second), and the like that can represent the driving speed of the fan motor 120 and the tilt motor 130 However, these terms only represent the speed of the motor itself and do not reflect the driving speed when moving the actual product. When using a real motor, it uses a gear (torque transfer enhancement) and a microstep (precision improvement) instead of using only one motor, so it moves at a speed different from the actual motor rotation speed. In addition, since the angle of view shown on the actual screen is narrowed as the zooming operation is performed, the driving speed corresponding to the narrowed angle of view also decreases. Therefore, when the image is transmitted to the image compressing unit 170, the angle of movement per second The driving speed value is transmitted.

The decoder 150 decodes the analog image captured by the camera 110 into a digital signal under the control of the controller 190.

The image processing unit 160 resizes the decoded video signal under various control conditions of the control unit 190 to various resolutions suitable for each use destination (for example, 1920 × 1080 or 800 × 600) 170).

The image compression unit 170 adjusts the compression ratio of the image data output from the image processing unit 160 according to the control signal from the control unit 190 and compresses the image data.

The external interface unit 180 is an interface that supports a path through which the camera 100 can communicate with the external control apparatus 300 through the network 200. [ For example, when a pan / tilt speed control command is inputted from the external control device 300, the pan / tilt speed control command is transmitted to the controller 190 through the external interface unit 180, Tilt speed and direction control through speed and direction control, and outputs it to the motor control unit 140.

The control unit 190 adjusts the compression rate of the image compression unit 170 according to the driving speeds of the fan motor 120 and the tilt motor 130 received from the motor control unit 140. The control unit 190 controls the image compression unit 170 to perform image compression according to a preset image compression rate in the absence of the movement of the fan motor 120 and the tilt motor 130. [

The control unit 190 receives the driving speed from the motor control unit 140 when the movement occurs from at least one of the fan motor 120 and the tilt motor 130 and compares the driving speed with the set reference speed, Is adjusted. Here, the reference speed can be changed. When the driving speed of the control unit 190 is lower than the reference speed, the image compressing unit 170 is controlled so that the image compression is performed according to a preset image compression ratio. The control unit 190 controls the image compressing unit 170 so that image compression is performed in a case where the driving speed of the control unit 190 is higher than the reference speed.

In the case of the manual operation command, the user operates the fan motor 120 and the tilt motor 130 while viewing the screen directly, so that the object can be identified and there is no crushing of the screen. It is necessary to be able to recognize the state of the screen while the fan motor 120 and the tilt motor 130 move. However, in the case of the preset execution command, it is possible to move the camera to the pre-stored position as fast as possible, so that the state of the screen can not be accurately viewed when the camera 110 is moved. The control unit 190 determines the reference speed of the fan motor 120 and the tilt motor 130 for controlling the image compression ratio to be the maximum manual speed (for example, 120 degrees / sec). If the driving speed is less than the reference speed The image compressing unit 170 controls the image compressing unit 170 to compress the image in a normal situation when the image compressing is performed and controls the compression of the image compressing unit 170 to be performed when the driving speed is equal to or higher than the reference speed.

For example, when the fan motor 120 and the tilt motor 130 are not moving, the control unit 190 may control the image compression unit 170 to perform compression by setting the number of image compression frames to 30 frames . The control unit 190 compares the driving speed with the reference speed, and when the driving speed is lower than the reference speed, the image compression unit 170 can be controlled to perform compression by setting the number of image compression frames to 30 frames, The image compressing unit 170 can be controlled so that compression is performed by setting the number of image compression frames to 5 frames.

As described above, since the data change and the directionality between image frames can be predicted without performing the image analysis through the driving speed and the driving direction information of the fan motor 120 and the tilt motor 130, it is effective to perform image compression. In particular, since the validity can be determined before analyzing the corresponding image according to the driving speed information of the fan motor 120 and the tilt motor 130, the system resources allocated to compression can be efficiently managed and the overall efficiency is increased .

Next, an image processing method according to an embodiment of the present invention will be described with reference to FIG. The image processing method according to the present invention can be performed in the controller 190 with the help of peripheral components as shown in FIGS. 1 and 2. In the following description, the description of the parts that are the same as those in FIG. 1 and FIG. 2 will be omitted.

Referring to FIG. 3, the control unit 190 controls the image compression unit 170 to compress the image frames photographed by the camera 110 in the surveillance region with a predetermined number of image frames (S100) do.

The control unit 190 drives at least one of the fan motor 120 and the tilt motor 130 included in the camera 110 to move the camera 110 according to the monitoring mode in operation S200. Here, the monitoring mode may be a preset mode in which a preset is moved from a preset to another preset, or a manual mode in which the user moves from one surveillance area to another surveillance area.

The control unit 190 performs a step S300 of comparing the driving speeds of the fan motor 120 and the tilt motor 130 received from the motor control unit 140 and the set reference speed when the camera 110 moves. In the manual mode, since the user directly operates the fan motor 120 and the tilt motor 130 while viewing the screen, the object can be identified and there is no crushing of the screen. It is necessary to be able to recognize the state of the screen while the fan motor 120 and the tilt motor 130 move. However, in the case of the preset mode, it is possible to precisely view the state of the screen when moving the camera 110 because it has a purpose of moving the stored position as fast as possible. The control unit 190 may determine the reference speed of the fan motor 120 and the tilt motor 130 for controlling the image compression rate to be the maximum speed in the manual mode (for example, 120 degrees / sec).

The control unit 190 compares the driving speed with the reference speed, and when the driving speed is equal to or higher than the reference speed, the control unit 190 compresses the number of image frames photographed by the camera 110, (S400). ≪ / RTI > For example, when the fan motor 120 and the tilt motor 130 are not moving, the control unit 190 may control the image compression unit 170 to perform compression by setting the number of image compression frames to 30 frames . The control unit 190 compares the driving speed with the reference speed, and when the driving speed is lower than the reference speed, the image compression unit 170 can be controlled to perform compression by setting the number of image compression frames to 30 frames, The image compressing unit 170 can be controlled so that compression is performed by setting the number of image compression frames to 5 frames.

The use of the terms "above" and similar indication words in the specification of the present invention (particularly in the claims) may refer to both singular and plural. In addition, in the present invention, when a range is described, it includes the invention to which the individual values belonging to the above range are applied (unless there is contradiction thereto), and each individual value constituting the above range is described in the detailed description of the invention The same.

Unless there is explicitly stated or contrary to the description of the steps constituting the method according to the invention, the steps may be carried out in any suitable order. The present invention is not necessarily limited to the order of description of the above steps. The use of all examples or exemplary language (e.g., etc.) in this invention is for the purpose of describing the present invention only in detail and is not to be limited by the scope of the claims, It is not. It will also be appreciated by those skilled in the art that various modifications, combinations, and alterations may be made depending on design criteria and factors within the scope of the appended claims or equivalents thereof.

Accordingly, the spirit of the present invention should not be construed as being limited to the above-described embodiments, and all ranges that are equivalent to or equivalent to the claims of the present invention as well as the claims .

100: image processing apparatus 110: camera
120: Fan motor 130: Tilt motor
140: Motor control unit 150: Decoder
160: Image processing unit 170: Image compression unit
180: External interface unit 190: Control unit
200: Network 300: External control device

Claims (6)

A camera for photographing a surveillance area;
A compression unit for compressing the image frames photographed by the camera with a predetermined number of image frames;
A pan / tilt motor for horizontally and vertically rotating the camera;
A motor control unit for controlling driving of the pan / tilt motor and calculating a driving speed at the time of moving the pan / tilt motor according to a monitoring mode; And
Wherein the control unit compares the driving speed received from the motor control unit with a predetermined reference speed to reduce the number of image frames photographed by the camera when the driving speed is equal to or greater than the reference speed, And a control unit for controlling the compression unit. The camera according to claim 1,
Wherein the preset mode is a preset mode in which a preset is moved from a preset to a different preset among a plurality of presets. The camera according to claim 1,
And operates in a manual mode for moving from an arbitrary surveillance area to another surveillance area by an operation of a user. Controlling to compress the image frames photographed by the camera in the surveillance region with a predetermined number of image frames;
Driving at least one of a fan motor and a tilt motor included in the camera according to a monitoring mode to move the camera;
Comparing the drive speed of the motor received from at least one of the fan motor and the tilt motor with a set reference speed; And
And controlling the number of image frames photographed by the camera to be smaller than the set number of image frames when the driving speed is equal to or higher than the reference speed. 5. The method of claim 4, wherein moving the camera further comprises:
And moving the camera by driving at least one of the fan motor and the tilt motor when moving from an arbitrary preset to another preset among a preset plurality of presets. 5. The method of claim 4, wherein moving the camera further comprises:
And moving the camera by driving at least one of the fan motor and the tilt motor when moving from an arbitrary surveillance area to another surveillance area by manual operation of the user.

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