KR20090072508A - Apparatus for processing digital image and method for controlling thereof - Google Patents

Abstract

A digital image processing apparatus and a control method thereof are provided to make a subject photographed in the center of a screen although the screen composition is poor in the state that the location of the digital image processing apparatus is fixed. A digital image processing apparatus recognizes the face of a person from an inputted image(S320), determines whether the facial region is positioned in the center of a screen(S330), expands the angle of view in case the space for expanding the view angle exists(S350), and then changes the frame of the inputted image so that the facial region can be positioned in the center of the screen(S360).

Description

Apparatus for processing digital image and method for controlling Technical Field

The present invention relates to a digital image processing apparatus and a control method thereof, and more particularly, to a digital signal processor for processing an image received through an image pickup device and compressing the image to generate an image file, and to store the image file in a memory. The present invention relates to a digital image processing apparatus and a control method thereof.

Typically, the digital image processing apparatus includes all devices that process images such as a digital camera, a personal digital assistant (PDA), a phone camera, a PC camera, or use an image recognition sensor.

The digital image processing apparatus may image an image received through an image pickup device by a digital signal processor, compress the image, generate an image file, and store the image file in a memory.

In addition, the digital image processing apparatus may display and display an image of an image file received through an imaging device or stored in a storage medium on a display device such as a liquid crystal display (LCD).

In this case, the image input and captured through the imaging device may be displayed on a display device such as an LCD, so that the user may check whether the acquired image is a desired image.

Meanwhile, an image including an operator may be photographed by self photographing. In this case, it is difficult for the operator to check his or her appearance, and thus the composition of the human subject may not be properly captured at the time of shooting.

The present invention provides a digital image processing apparatus and a method of controlling the same so that the subject can be photographed at the center of the screen even when the position of the digital image processing apparatus for photographing is fixed and the composition of the subject is not correct. It aims to provide.

The present invention, (a) receiving an input image; (b) recognizing a face of a person in the input image; And (c) changing a frame of the input image so that the face area is positioned at the center of the screen when the face area occupied by the face on the screen of the input image is not located at the center of the screen. A control method of a digital image processing apparatus is provided.

The step (c) may include determining whether the face area is located at the center of the screen, enlarging the angle of view when there is room to enlarge the view angle, and positioning the face area at the center of the screen. The method may include changing a frame of the input image so as to change the frame.

The method may further include storing a frame image generated by changing a frame in the input image.

Another aspect of the invention, the image input unit for receiving an input image; When the face of the person is recognized in the input image and the face area occupied on the screen of the input image is not located at the center of the screen, the face area is positioned at the center of the screen. A control unit for controlling the frame to be changed; And a storage unit for storing the frame image of the changed frame.

The apparatus may further include an angle of view adjusting unit configured to adjust an angle of view of the input image.

According to the digital image processing apparatus and the control method thereof according to the present invention, even when the composition of the subject image is not correct, the subject is photographed at the center of the screen in a fixed state. Can be.

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

FIG. 1 is a rear view of a digital camera 100, which is an embodiment of a control device of a digital image processing apparatus and a digital image processing apparatus to which the method is applied, according to the present invention.

Referring to the drawings, on the back of the digital camera 100, the direction button 21, the menu-OK button 22, the wide angle (Zoom) button (W), the telephoto (Zoom) ) Button T, the display panel 25 and the like.

The direction button 21 may include four buttons, an up button 21a, a down button 21b, a left button 21c, and a right button 21d. The direction button 21 and the menu-OK button 22 are keys input for executing various menus relating to the operation of the digital image processing apparatus such as a digital camera.

The wide-angle zoom button W or the tele-zoom button T has a wider angle of view or a narrower angle of view depending on its input. In particular, it may be used to change the size of the selected exposure area. As the display panel 25, an image display device such as a liquid crystal display (LCD) may be used.

The display panel 25 may be included in the display unit 750 of FIG. 5 in which an input image and a target image generated by changing an angle of view and a frame may be displayed therefrom.

Meanwhile, a shutter release button 26, a flash (not shown), a power switch 28, and a lens unit (not shown) may be provided on the front or top surface of the digital camera 100. In addition, the front and rear of the digital camera 100 may be provided with an objective lens and an eyepiece of the viewfinder 27.

The direction button 21, the menu-OK button 22, the shutter release button 26, the power switch 28, and the like are included in the user control unit 760 (FIG. 5) for inputting items that the user wants to operate from the outside. Can be.

The shutter release button 26 is opened and closed to expose the film or an image pickup device such as a charge coupled device (CCD) for a predetermined time. In addition, the shutter release button records an image on the image pickup device by properly exposing a subject in association with an aperture (not shown).

On the other hand, the shutter release button 26 can be pressed in two stages. When the shutter release button 26 is pressed to one end, the first signal S1 may be generated, and when pressed to the second stage, the second signal S2 may be generated. A photographing preparation operation may be performed by the first signal S1, and photographing may be performed by the second signal S2.

As an embodiment of a digital image processing apparatus to which the present invention can be applied, a digital camera, a control apparatus, and a control method thereof are disclosed in US Patent Application Publication No. 2004/0130650 (name: automatic using a secondary function of the camera). Method of automatically focusing using a quadratic function in camera.

Matters relating to the digital camera, the control apparatus, and the control method disclosed in the above-mentioned US application will be included in the present specification, the detailed description thereof will be omitted.

2 is a block diagram of a control device 200 of a digital image processing apparatus, which is a preferred embodiment of the present invention. The control device 200 of the digital image processing apparatus may be mounted in the digital camera 100 of FIG. 1.

Referring to the drawing, an optical system OPS including a lens unit and a filter unit optically processes light from a subject. The lens unit of the optical system OPS includes a zoom lens, a focus lens, and a compensation lens. When the user presses the wide-angle zoom button W or the tele-zoom button T included in the user input unit INP, a signal corresponding thereto is input to the microcontroller 212.

Accordingly, as the microcontroller 212 controls the lens driver 210, the zoom motor M _Z is driven to move the zoom lens. That is, when the wide-zoom button W is pressed, the focal length of the zoom lens is shortened to widen the angle of view, and when the tele-zoom button T is pressed, the focal length of the zoom lens is increased, thereby narrowing the angle of view.

The zoom lens and the zoom motor M _Z may be included in the angle of view adjusting unit 770 of FIG. 5 to adjust the angle of view of the input image according to the present invention.

On the other hand, in the auto focusing mode, the main controller embedded in the digital signal processor 207 controls the lens driver 210 through the microcontroller 212, whereby the focus motor M _F is driven. do. That is, the focus lens is moved to a position where the sharpest picture is obtained by driving the focus motor M _F.

The compensation lens compensates for the overall refractive index and is not driven separately. Reference numeral M _A denotes a motor for driving an aperture (not shown).

In the filter section of the optical system OPS, an optical low pass filter removes optical noise of high frequency components. Infra-Red cut filter cuts the infrared component of the incident light.

The photoelectric conversion unit OEC may include an imaging device such as a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS). The photoelectric conversion unit OEC converts light from the optical system OPS into an electrical analog signal.

The analog-to-digital converter may include a CDS-ADC (Correlation Double Sampler and Analog-to-Digital Converter) device 201. The analog-to-digital converter processes the analog signal from the photoelectric converter (OEC), removes the high frequency noise, adjusts the amplitude, and converts the analog signal into a digital signal. Here, the digital signal processor 207 controls the timing circuit 202 to control the operation of the photoelectric converter OEC and the analog-to-digital converter 201.

The optical system OPS, the photoelectric conversion unit OEC, the CDS-ADC device 201, and the like may be included in the image input unit 710 of FIG. 5.

The real time clock 203 provides time information to the digital signal processor 207. The digital signal processor 207 processes digital signals from the CDS-ADC element 201 to generate digital image signals classified into luminance (Y value) and chromaticity (R, G, B) signals.

The light emitting unit LAMP driven by the microcontroller 212 under the control of the main controller built in the digital signal processor 207 includes a self-timer lamp, an auto-focus lamp, a mode indicating lamp, a flash standby lamp, and the like. May be included.

The digital signal processor 207 and / or the microcontroller 212 may be included in the controller 720 of FIG. 5 in accordance with the present invention. In addition, a user input input by an operation of the user manipulation unit 750 of FIG. 5 is input to the digital signal processor 207 and / or the microcontroller 212 through the user input unit INP, and processed. The work accordingly can be performed.

The digital image signal from the digital signal processor 207 is temporarily stored in the DRAM (Dynamic Random Access Memory) 204. The EEPROM (Electrically Erasable and Programmable Read Only Memory) 205 stores algorithms and setting data such as a boot program and a key input program required for the operation of the digital signal processor 207. In the memory card interface 206, a user's memory card may be attached or detached.

The memory card recognized through the DRAM 204 or the memory card interface 206 may store an input image and an enlarged image temporarily or nonvolatilely. The first storage unit 730 and / or the second storage unit of FIG. 740 may be included.

In this case, the input image and / or the magnified image may be temporarily stored in the first storage unit 730. That is, the first storage unit 730 may be a DRAM 204 or a cache memory in which an input image and / or an enlarged image are temporarily stored.

In addition, the second storage unit 740 may store the target image in a non-volatile manner. That is, the second storage unit 740 may be a flash memory or a memory card mounted to be detachable.

The digital image signal from the digital signal processor 207 is input to the display panel driver 214, whereby the image is displayed on the display panel 215. The display panel 215 may be driven by the display panel driver 214 under the control of the digital signal processor 207.

The display panel 215 and the display panel driver 214 may be included in the display unit 750 of FIG. 5 in which an input image and a target image generated by changing an angle of view and a frame change therefrom can be displayed.

On the other hand, the digital image signal from the digital signal processor 207 can be transmitted by serial communication via a universal serial bus (USB) connection portion 31a or an RS232C interface 208 and the connection portion 31b thereof, and a video filter ( 209 and through the video output unit 31c. Here, the digital signal processor 207 may incorporate a microcontroller therein.

The audio processor 213 outputs the audio signal from the microphone MIC to the digital signal processor 207 or the speaker SP, and outputs the audio signal from the digital signal processor 207 to the speaker SP.

3 is a flowchart of a control method (S300) of a digital image processing apparatus as a preferred embodiment according to the present invention. 4A to 4D illustrate exemplary embodiments of the input image 40, the magnified image 50, and the target image 60 in the control method S300 of the digital image processing apparatus of FIG. 3, respectively.

The control method S300 of the digital image processing apparatus may be implemented in the control apparatus 200 of the digital image processing apparatus of FIG. 2 and / or the digital image processing apparatus 700 of FIG. 5. To this end, the control method S300 of the digital image processing apparatus according to the present invention may be a program or algorithm stored in the storage means of FIG. 2 or implemented in the form of a semiconductor chip such as firmware.

The control method (S300) of the digital image processing apparatus according to the present invention relates to a method for automatically photographing a subject that is not composed at the time of shooting by automatically moving to the center of the screen. In particular, even when the composition of the human subject does not match when taking a self-portrait can be automatically moved to the center of the screen to shoot.

That is, even if the human subject moves freely within the angle of view margin of the lens, the human subject may be photographed to be positioned at the center of the screen without moving the digital image processing apparatus.

To this end, the control method (S300) of the digital image processing apparatus includes an image input step (S310); Face recognition step (S320); And frame changing steps (S330 to S360).

In the image input step S310, an input image is received. In the face recognition step S320, a face of a person is recognized from an input image. In the frame modification steps S330 to S360, when the face area occupied by the face of the input image is not located at the center of the screen, the frame of the input image is changed so that the face area is located at the center of the screen.

The frame modification steps S330 to S360 may include a face area position determination step S330, an angle of view enlargement step S340 and S350, and a frame change step S360.

In the face region position determination step (S330), it is determined whether the face region is located at the center of the screen. In the angle of view enlargement steps S340 and S350, the angle of view is enlarged when there is room for enlargement of the angle of view. In the frame changing step (S360), the frame of the input image is changed so that the face area is located at the center of the screen.

The image input step S310 may receive an input image from the outside. In this case, the input image may be input through the image input unit 710 of FIG. 5 including the optical system OPS, the photoelectric conversion unit OEC, the CDS-ADC device 201, and the like.

In the face recognition step S320, a face of a person may be recognized in the input image 40. In this case, the face of the person may be recognized by a conventional face recognition method. Face recognition may be an area where a human face color is distributed on the entire screen. In this case, the face area 41 may be recognized as a rectangular area as shown in FIGS. 4A to 4C.

In this case, in the present invention, a face of a person may be recognized in the face recognition step S320, but as another embodiment, a general subject may be recognized. In this case, the recognized subject may be controlled to be positioned at the center of the image.

In the face region position determination step (S330), it may be determined whether the face region 41 is positioned at the center of the screen of the input image 40. As an exemplary embodiment, when the center point 40a of the screen is positioned inside the face area 41, it may be determined that the face area 41 is located at the center of the screen.

As another example, if the distance from the center point 41a of the face area 41 is less than or equal to the set reference distance, it may be determined that the face area is located at the center of the screen.

As a result of the determination in the face region position determining step S330, when it is determined that the position of the face region 40 is located at the center of the input image 40, the frame modification steps S330 to S360 may not be performed. Can be.

In the angle of view enlargement steps S340 and S350, it is determined whether there is room to enlarge the angle of view (S340). By determining whether there is room to enlarge the angle of view (S340), when there is no room to enlarge, the frame change step (S360) may be performed without enlarging the angle of view.

In this case, the enlargement of the angle of view may be performed by adjusting the zoom magnification to be lowered by the optical zoom. When the zoom magnification is high, an image of which the subject is enlarged by narrowing the angle of view may be input. When the zoom magnification is low, the image which is widened and the subject is reduced may be input.

As shown in FIGS. 4B and 4C, the degree of zoom magnification to be adjusted may be a magnification such that a subject, for example, a human subject may be positioned at the center part by the frame change in the frame changing step S360.

In this case, an enlarged view 50 as shown in FIG. 4B can be obtained by enlarging the angle of view. Therefore, the image margin 51 corresponding to the difference between the input image 40 and the enlarged image 50 can be obtained. Therefore, in the frame changing step S360, a margin for changing the frame as much as the image margin 51 is generated.

Accordingly, when the view angle is enlarged due to the margin of view angle, only the composition of the screen is adjusted in the image of the same size, so that the image intended by the user can be obtained.

In the frame changing operation S360, the frame of the input image may be changed so that the face area is positioned at the center of the screen. As an exemplary embodiment, the frame of the input image 40 may be changed such that the center point 41a of the face area 41 is positioned at the center point 60a of the screen, that is, the target image 60. Thus, the face area 41 can be located at the center of the screen.

In this case, as illustrated in FIGS. 4C and 4D, the center point 41a of the face area 41 and the center point 60a of the target image 60 may be the same point on the screen.

On the other hand, the control method (S300) of the digital image processing apparatus may further include a storage step (S370) for storing the target image 60 corresponding to the frame image generated by changing the frame in the input image.

In this case, the object image 60 may be stored after image processing and compression of a portion corresponding to the object image 60 among the entire magnified image 50.

According to the present invention, when the position of the digital image processing apparatus for photographing is fixed, even when the composition of the screen of the subject is not correct, the subject may be positioned at the center of the screen and photographed.

5 is a block diagram of a digital image processing apparatus 700 according to a preferred embodiment of the present invention. The digital image processing apparatus 700 may be controlled by the control method S300 of the digital image processing apparatus illustrated in FIG. 3. 4A to 4D illustrate exemplary embodiments of the input image 40, the magnified image 50, and the target image 60 in the control method S300 of the digital image processing apparatus of FIG. 3, respectively.

Referring to the drawings, the digital image processing apparatus 700 includes an image input unit 710; A controller 720; Storage units 730 and 740; Display unit 750; User operation unit 760; And an angle of view adjustment unit 770. The digital image processing apparatus 700 is controlled by the control method S300 of the digital image processing apparatus illustrated in FIG. 3, and the same as in the description of FIG. 3 will be referred to.

The image input unit 710 receives an input image. The controller 720 recognizes a person's face in the input image, and when the face occupies the screen of the input image, the face region is located at the center of the screen, when the face region is not located at the center of the screen. Control it to change. The angle of view adjusting unit 770 adjusts the angle of view of the input image.

The storage 730 and 740 may store an input image, an enlarged image, and a target image. The display unit 750 may display an input image, an enlarged image, and a target image. The user operation unit 760 manipulates a user to input a desired command from the outside.

The image input unit 710 receiving the input image may include the optical system OPS, the photoelectric conversion unit OEC, the CDS-ADC device 201, and the like of FIG. 2.

The controller 720 may recognize a face of a person in the input image. The human face may be recognized by a conventional face recognition method. In this case, the face area 41 may be recognized as a rectangular area as shown in FIGS. 4A to 4C.

In addition, the controller 720 may determine whether the face area 41 is positioned at the center of the screen of the input image 40. In this case, when the center point 40a of the screen is positioned inside the face area 41, it may be determined that the face area 41 is located at the center of the screen.

As another example, if the distance from the center point 41a of the face area 41 is less than or equal to the set reference distance, it may be determined that the face area is located at the center of the screen.

The controller 720 may control the frame of the input image to be changed so that the face region is positioned at the center portion of the screen when the face area occupied by the face on the screen of the input image is not positioned at the center portion of the screen.

To this end, the controller 720 may determine whether there is room to enlarge the angle of view, and may enlarge the field of view when there is room to enlarge the field of view. In this case, the enlargement of the angle of view may be performed by adjusting the zoom magnification to be lowered by the optical zoom.

To this end, the digital image processing apparatus 700 may be provided with an angle of view adjusting unit 770 for adjusting the angle of view. The angle of view adjusting unit 770 may include a zoom lens and a zoom motor M _Z to adjust the zoom magnification of FIG. 2.

As shown in FIGS. 4B and 4C, the degree of zoom magnification to be adjusted is preferably a magnification such that the human subject can be positioned at the center of the screen by changing the frame. In this case, an enlarged view 50 as shown in FIG. 4B can be obtained by enlarging the angle of view. Therefore, the image margin 51 corresponding to the difference between the input image 40 and the enlarged image 50 can be obtained.

In addition, the controller 720 may change the frame of the input image so that the face area is located at the center of the screen. In one embodiment, the input image such that the center point 41a of the face area 41 is positioned on the screen, that is, the center point 60a of the target image 60 so that the face area 41 may be located at the center of the screen. The frame of 40 can be changed.

The storage 730 and 740 may store an input image, an enlarged image, and a target image. The storage units 730 and 740 may include a first storage unit 730 and a second storage unit 740. In this case, the input image and the enlarged image may be temporarily stored in the first storage unit 730. In the second storage unit 740, the target image may be non-volatilely stored as a photographing result.

The first storage unit 730 may be a DRAM (204 of FIG. 2) or a cache memory that temporarily stores data. The second storage unit 740 stores data non-volatilely and may be a flash memory or a memory card recognized through the memory card interface 206 of FIG. 2.

The user manipulation unit 760 may be manipulated by a user to input a desired command from the outside. The direction buttons (21 in FIG. 1), the menu-OK button (22 in FIG. 1), the shutter release button (26 in FIG. 1), the power switch (28 in FIG. 1), and the like are connected to the user control panel (760 in FIG. 5). May be included.

According to the present invention, when the position of the digital image processing apparatus for photographing is fixed, even when the composition of the screen of the subject is not correct, the subject may be positioned at the center of the screen and photographed.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, it is merely an example, and those skilled in the art may realize various modifications and equivalent other embodiments therefrom. I can understand. Accordingly, the true scope of protection of the invention should be defined only by the appended claims.

1 is a diagram illustrating a rear surface of a digital camera as an embodiment of a digital image processing apparatus according to the present invention.

FIG. 2 is a block diagram schematically illustrating a control apparatus that may be included in the digital camera of FIG. 1.

3 is a flowchart schematically illustrating a control method of a digital image processing apparatus as a preferred embodiment according to the present invention.

4A is a view schematically illustrating an input image in the method of controlling the digital image processing apparatus of FIG. 3.

4B is a diagram schematically illustrating an enlarged image in which an input image is enlarged in the control method of the digital image processing apparatus of FIG. 3.

FIG. 4C is a view schematically illustrating a target image in which a frame is changed and selected in the enlarged image in the control method of the digital image processing apparatus of FIG. 3.

FIG. 4D is a view schematically illustrating an object image finally stored by the control method of the digital image processing apparatus of FIG. 3.

5 is a block diagram schematically showing a digital image processing apparatus as a preferred embodiment according to the present invention.

Claims (13)

(a) receiving an input image; (b) recognizing a face of a person in the input image; And (c) changing a frame of the input image so that the face area is positioned at the center of the screen when the face area occupied by the face on the screen of the input image is not located at the center of the screen; Control method of digital image processing apparatus. The method of claim 1, In step (c), Determining whether the face area is located at the center of the screen; Enlarging the angle of view when there is room for enlargement of the angle of view, and And changing a frame of the input image so that the face area is located at the center of the screen. The method of claim 2, And when the center point of the screen is located inside the face area, determining that the face area is located at the center of the screen. The method of claim 2, And when the distance from the center point of the face area is less than or equal to a set reference distance, determining that the face area is located at the center of the screen. The method of claim 2, And changing the frame of the input image so that the center point of the face area is located at the center point of the screen so that the face area is located at the center of the screen. The method of claim 2, And controlling the zoom magnification to be lower, thereby enlarging the angle of view. The method of claim 1, And storing a frame image generated by changing a frame in the input image. An image input unit which receives an input image; When the face of the person is recognized in the input image and the face area occupied on the screen of the input image is not located at the center of the screen, the face area is positioned at the center of the screen. A control unit for controlling the frame to be changed; And And a storage unit for storing the frame image of the changed frame. The method of claim 8, And an angle of view controller configured to adjust an angle of view of the input image. The method of claim 9, Digital image processing apparatus for changing the frame of the input image to enlarge the angle of view when the face area is not located in the center of the screen, if there is room to enlarge the angle of view, and the face area is located in the center of the screen . The method of claim 10, A digital image processing apparatus for enlarging the angle of view by adjusting the zoom magnification to be lower. The method of claim 10, And when the center point of the screen is located inside the face area, determining that the face area is located at the center of the screen. The method of claim 10, And determine that the face area is located at the center of the screen when the center point of the face area is less than or equal to a set reference distance.

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