KR102339662B1 - Image photographing apparatus and control methods thereof - Google Patents

Abstract

A photographing apparatus is disclosed. The photographing apparatus includes an image sensor including a plurality of image pixels for sensing an image by collecting light input through a lens and a plurality of phase sensing pixels for detecting a phase, and a region of interest among the image sensors Divide into a plurality of sub-ROIs, calculate disparity information on a subject corresponding to each of the plurality of sub-ROIs by using a phase detection pixel included in each of the plurality of sub-ROIs, and and a processor for determining a focal region within the region of interest based on parity information. Accordingly, the user's convenience is increased.

Description

Filming device and its control method { IMAGE PHOTOGRAPHING APPARATUS AND CONTROL METHODS THEREOF }

The present invention relates to a photographing apparatus and a method for controlling the same, and more particularly, to a photographing apparatus for photographing a subject by automatically determining a focus area and a method for controlling the same.

In general, focusing methods include a contrast detection method and a phase difference detection method (Phase Auto Focus).

1A is a diagram for explaining a contrast detection method. The contrast detection method is to adjust the lens position up to the position with the highest contrast by using this characteristic, in which the contour of an accurate-focused picture is clear and the contrast rises. That is, while changing the position of the lens, the contrast for each position is measured, and the lens is adjusted to the position of the lens having the highest contrast to achieve focus.

1B is a diagram for explaining a phase difference detection method. The phase difference detection method is a method of detecting the actual focus position after determining to what extent the focus is achieved by using the phase difference between the phase detection pixels in one image.

Although the small camera used the contrast detection method, it had the disadvantage of being slow, and the DSLR (Digital Single-Lens Reflex) used the phase difference detection method, but had the disadvantage of being inaccurate compared to the contrast detection method. Accordingly, recently, a method for obtaining a focus by mixing the two methods has been developed.

However, even if the method of obtaining focus by mixing the two methods is used, since the DSLR provides a plurality of focus areas as shown in FIG. There is a problem that it cannot. That is, there is a problem in that a focus area must be determined regardless of a focusing method.

In addition, a function of determining a focus area by recognizing a person's face may be provided in the small camera as shown in FIG. 2B, but there is a disadvantage in that there is a limitation in using such a function if it is not a human face.

Also, in the case of a small camera, if a contrast detection method is used to focus, a contrast value as shown in FIG. 1A may be obtained. In this case, the small camera determines the lens position corresponding to the highest contrast value on the right. However, in this case, the user may want to set the lens position corresponding to the second highest contrast value from the left. This problem cannot be solved by additionally using the phase difference detection method, and there is a problem in that the subject cannot be photographed by the user.

The present invention is to solve the above-described problems, and an object of the present invention is to quickly analyze information on a plurality of subjects even when there are a plurality of subjects and automatically determine a focus area for any one subject to perform shooting. An object of the present invention is to provide a photographing apparatus and a method for controlling the same.

A photographing apparatus according to an embodiment of the present invention for achieving the above object includes a plurality of image pixels for detecting an image by collecting light input through a lens and a plurality of phase detection pixels for detecting a phase An image sensor and a region of interest among the image sensors are divided into a plurality of sub-regions of interest, and a phase detection pixel included in each of the plurality of sub-regions of interest is used to detect the plurality of sub-regions of interest. and a processor that calculates disparity information on the subject and determines a focus area within the ROI based on the disparity information.

Also, the processor may calculate a movement distance and reliability information of the lens corresponding to the position of the lens based on the disparity information to determine a focus area within the ROI.

In addition, the processor is configured to: a first pair consisting of a central sub-region of interest and a peripheral sub-region of the region of interest; a second pair consisting of a left sub region of interest and a right sub region of interest of the region of interest; and an upper sub region of the region of interest. The ROI may be divided into a third pair including a region of interest and a lower sub region of interest.

In addition, the processor calculates a movement distance of the lens for focusing on the sub-ROIs included in the first pair to the third pair, and calculates a movement distance of the lens among the first pair to the third pair. By determining the pair having the largest difference, one sub-ROI among the pair having the largest difference in the movement distance of the lens may be determined as the focus region.

And, further comprising a display and a user interface for receiving a user input, wherein the processor controls the display to display a UI indicating a pair having the largest difference in the movement distance of the lens, and the difference in the movement distance of the lens When a user input for selecting one of the largest pairs is received, the selected sub-ROI may be determined as a focus region.

In addition, the processor divides the ROI into M rows and N columns of the same size, and groups the adjacent sub ROIs when a difference in movement distance of the lens with respect to the adjacent sub ROIs is less than or equal to a preset size. , a focal region within the ROI may be determined.

In addition, the processor may determine, as the focus area, one of a group having the closest distance to the subject, a group having the highest reliability, and a group having the most sub-ROIs.

Also, the processor may group only the sub-ROIs in which the reliability of the sub-ROI is greater than a preset reliability.

In addition, the moving distance of the lens may be information determined from the disparity information calculated by a phase difference detection method (Phase Auto Focus) with respect to the position of the lens.

In addition, the processor is configured to detect an image using two phase sensing pixels corresponding to each of the plurality of sub-ROIs, and cross-correlate the two images to calculate disparity information. can

Meanwhile, according to an embodiment of the present invention, the control of a photographing apparatus having an image sensor including a plurality of image pixels for sensing an image by collecting light input through a lens and a plurality of phase sensing pixels for detecting a phase In the method, dividing a region of interest in the image sensor into a plurality of sub-regions of interest; and calculating disparity information on a corresponding subject, and determining a focus area within the ROI based on the disparity information.

In addition, the determining of the focus area includes calculating a movement distance and reliability information of the lens corresponding to the position of the lens based on the disparity information, and using the movement distance and reliability information of the lens. determining a focal region within the region of interest.

And, the dividing into the plurality of sub-ROIs may include a first pair of a central sub-ROI and a peripheral sub-ROI of the ROI, and a second pair of the left sub-ROI and the right sub-ROI of the ROI. The ROI may be divided into a third pair including a pair and an upper sub ROI and a lower sub ROI of the ROI.

In addition, the determining of the focus area includes calculating a movement distance of the lens for focusing on sub-ROIs included in the first pair to the third pair, and the first pair to the third pair The method may include determining a pair having the largest difference in the movement distances of the lenses, and determining a sub-ROI of one of the pairs having the largest difference in the movement distances of the lenses as the focus area.

In addition, the determining of the focus area includes displaying a UI indicating a pair having the largest difference in the movement distance of the lenses and receiving a user input for selecting one of the pair having the largest difference in the movement distance of the lenses The method may further include the step of: and determining the selected sub-ROI as a focus area.

In addition, the dividing the ROI into the plurality of sub ROIs includes dividing the ROI into M rows and N columns of the same size, and the determining of the focus region includes movement of the lens with respect to the adjacent sub ROIs. When the distance difference is equal to or less than a preset size, the adjacent sub-ROIs may be grouped to determine a focus area within the ROI.

In the determining of the focus area, one group among a group having the closest distance to the subject, a group having the highest reliability, and a group having the most sub-ROIs grouped may be determined as the focus area.

In addition, the determining of the focal region may include grouping only the sub-ROIs in which the reliability of the sub-ROI is greater than a preset reliability.

In addition, the moving distance of the lens may be information determined from the disparity information calculated by a phase difference detection method (Phase Auto Focus) with respect to the position of the lens.

In addition, the calculating of the disparity information may include detecting an image using two phase sensing pixels corresponding to each of the plurality of sub-ROIs, and cross-correlating the two images to Disparity information may be calculated.

According to various embodiments of the present disclosure as described above, the photographing apparatus may more rapidly calculate information about a subject, and automatically determine a focus area accordingly, thereby improving user satisfaction.

1 is a diagram for explaining a contrast detection method and a phase difference detection method.
2 is a view for explaining a problem of a method of setting a focus area according to the related art.
3 is a block diagram illustrating a configuration of a photographing apparatus according to an embodiment of the present invention.
4 is a view for explaining an image sensor according to an embodiment of the present invention.
5 is a diagram for explaining a method of determining a focus area by dividing an ROI according to an embodiment of the present invention.
6 is a diagram for explaining a method of calculating a movement distance of a lens from disparity information according to an embodiment of the present invention.
7 and 8 are diagrams for explaining a method of calculating a moving distance and reliability information of a lens for focusing according to an embodiment of the present invention.
9 is a diagram for explaining a method of designating a region of interest according to an embodiment of the present invention.
10 is a diagram for explaining a method of determining a focus area when an ROI is the entire image sensor according to an embodiment of the present invention.
11 is a block diagram illustrating a circuit configuration of a photographing apparatus according to an embodiment of the present invention.
12 is a view for explaining a method of correcting information on a movement distance of a lens according to an embodiment of the present invention.
13 is a flowchart illustrating a method of controlling a photographing apparatus according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings.

3 is a block diagram illustrating the configuration of a photographing apparatus 100 according to an embodiment of the present invention.

Referring to FIG. 3A , the photographing apparatus 100 includes an image sensor 110 and a processor 120 . In FIG. 3A, only the components involved in the operation according to various embodiments of the present disclosure are illustrated, and the remaining detailed components are omitted.

The image sensor 110 may include a plurality of image pixels for sensing an image by collecting light input through a lens and a plurality of phase sensing pixels for detecting a phase. The image sensor 110 serves to detect an image since most of the area is composed of image pixels. In addition, in order to focus based on the contrast detection method and the phase difference detection method, the image sensor 110 may include phase detection pixels at regular intervals between image pixels. Details of the image sensor 110 will be described later.

The processor 120 controls the overall operation of the photographing apparatus 100 .

The processor 120 is a configuration responsible for controlling the device in general, and may be mixed with a central processing unit, a microprocessor, a control unit, etc., and controls the overall operation of the device. It may be implemented as a system (System-on-a-chip or System on chip, SOC, SoC).

The processor 120 divides a region of interest among the image sensors into a plurality of sub regions of interest, and uses a phase sensing pixel included in each of the plurality of sub regions of interest to be a subject corresponding to each of the plurality of sub regions of interest. Disparity information for , may be calculated, and a focus area within the ROI may be determined based on the disparity information.

In addition, the processor 120 may determine a focus area within the ROI by calculating the movement distance and reliability information of the lens corresponding to the position of the lens based on the disparity information.

In addition, the processor 120 generates a first pair consisting of a central sub-region of interest and a peripheral sub-region of the region of interest, a second pair consisting of a left sub-region and a right sub-region of the region of interest, and an upper sub-ROI of the region of interest. The ROI may be divided into a third pair including the ROI and the lower sub ROI.

In addition, the processor 120 calculates a movement distance of the lens for focusing on the sub-ROIs included in the first pair to the third pair, and the difference between the movement distance of the lens among the first pair to the third pair is By determining the largest pair, a sub-ROI of one of the pairs having the largest difference in the lens movement distance may be determined as the focal region.

In addition, the photographing apparatus 100 further includes a display and a user interface for receiving a user input, and the processor 120 controls the display to display a UI indicating a pair having the greatest difference in movement distance of the lens, and When a user input for selecting one of the pairs having the largest difference in movement distance is received, the selected sub-ROI may be determined as the focus area.

In addition, the processor 120 divides the ROI into M rows and N columns of the same size, and groups adjacent sub ROIs when the difference in movement distances of lenses with respect to the adjacent sub ROIs is less than or equal to a preset size, A focus area within the area may be determined.

In addition, the processor 120 may determine, as the focus area, one of a group having the closest distance to the subject, a group having the highest reliability, and a group having the most sub-ROIs.

Also, the processor 120 may group only the sub-ROIs in which the reliability of the sub-ROIs is greater than the preset reliability.

Here, the movement distance of the lens may be information determined from disparity information calculated by the phase difference detection method with respect to the position of the lens based on the movement distance of the lens measured by the contrast detection method for focusing.

In addition, the processor 120 may detect an image using two phase detection pixels corresponding to each of the plurality of sub-ROIs, and cross-correlate the two images to calculate disparity information. have.

Hereinafter, a basic configuration and various embodiments will be described to help the understanding of the present invention.

3B is a block diagram illustrating a detailed configuration of a photographing apparatus 100' according to another embodiment of the present invention. Referring to FIG. 3B , the photographing apparatus 100 ′ includes an image sensor 110 , a processor 120 , a display 130 , a user interface unit 140 , a communication unit 150 , a storage unit 155 , and an audio processing unit 160 . ), an image processing unit 170 , a speaker 180 , a button 181 , and a microphone 182 . Among the components illustrated in FIG. 3B , detailed descriptions of parts overlapping with those illustrated in FIG. 3A will be omitted.

The processor 120 controls the overall operation of the photographing apparatus 100 using various programs stored in the storage unit 155 .

Specifically, the processor 120 includes the RAM 121 , the ROM 122 , the main CPU 123 , the graphic processing unit 124 , the first to n interfaces 125-1 to 125-n, and the bus 126 . include

The RAM 121 , the ROM 122 , the main CPU 123 , the graphic processing unit 124 , the first to n interfaces 125 - 1 to 125 -n, etc. may be connected to each other through the bus 126 .

The first to n-th interfaces 125-1 to 125-n are connected to the various components described above. One of the interfaces may be a network interface connected to an external device through a network.

The main CPU 123 accesses the storage unit 155 and performs booting using the O/S stored in the storage unit 155 . Then, various operations are performed using various programs stored in the storage unit 155 .

The ROM 122 stores an instruction set for system booting and the like. When a turn-on command is input and power is supplied, the main CPU 123 copies the O/S stored in the storage unit 155 to the RAM 121 according to the command stored in the ROM 122, and executes the O/S. Boot the system. When booting is completed, the main CPU 123 copies various application programs stored in the storage unit 155 to the RAM 121 , and executes the application programs copied to the RAM 121 to perform various operations.

The graphic processing unit 124 generates a screen including various objects such as icons, images, and texts by using a calculation unit (not shown) and a rendering unit (not shown). A calculation unit (not shown) calculates attribute values such as coordinate values, shape, size, color, etc. at which each object is to be displayed according to the layout of the screen based on the received control command. The rendering unit (not shown) generates screens of various layouts including objects based on the attribute values calculated by the calculation unit (not shown). The screen generated by the rendering unit (not shown) is displayed in the display area of the display 130 .

Meanwhile, the above-described operation of the processor 120 may be performed by a program stored in the storage unit 155 .

The storage unit 155 includes an O/S (Operating System) software module for driving the photographing apparatus 100 , movement distance information and reliability information of a lens corresponding to disparity information, information on a method of dividing an ROI, and a user It stores various data such as UI information to be provided to users.

In this case, the processor 120 may set a focus area, adjust a lens position for focusing, and display various UIs based on the information stored in the storage unit 155 .

The user interface unit 140 receives various user interactions. Here, the user interface unit 140 may be implemented in various forms according to an implementation example of the photographing apparatus 100 . When the photographing apparatus 100 is an expensive photographing apparatus 100, the user interface unit 140 may be implemented as a remote control receiver for receiving a remote control signal from a remote control device, a microphone for receiving a user's voice, or the like. In addition, when the photographing apparatus 100 is implemented as a touch-based portable terminal, the user interface unit 140 may be implemented in the form of a touch screen that forms a layer structure with a touch pad. In this case, the user interface unit 140 can be used as the above-described display 130 .

The audio processing unit 160 is a component that processes audio data. In the audio processing unit 160 , various processes such as decoding, amplification, and noise filtering on audio data may be performed.

The video processing unit 170 is a component that processes video data. The video processing unit 170 may perform various image processing, such as decoding, scaling, noise filtering, frame rate conversion, and resolution conversion, on video data.

The speaker 180 is a component that outputs various types of audio data processed by the audio processing unit 160 as well as various notification sounds or voice messages.

The button 181 may be various types of buttons such as a mechanical button, a touch pad 210 , a wheel, etc. formed in an arbitrary area such as the front, side, or rear of the main body of the photographing apparatus 100 .

The microphone 182 is configured to receive a user's voice or other sound and convert it into audio data. The microphone 182 may generate a control signal from the user's voice.

Hereinafter, a basic configuration and various embodiments will be described to help the understanding of the present invention.

4 is a diagram for explaining the image sensor 110 according to an embodiment of the present invention.

Referring to FIG. 4 , the image sensor 110 may include a plurality of image pixels and a plurality of phase detection pixels 410 and 420 . Most of the image sensor 110 is composed of image pixels, and the image pixels may detect an image by collecting light input through a lens. In FIG. 4 , it is expressed that the phase difference pixels are disposed at regular intervals, but for convenience of explanation, the image pixels may be disposed in all regions of the image sensor 110 except for the phase sensing pixels.

The plurality of phase detection pixels 410 and 420 are disposed at regular intervals between image pixels, and may detect a phase of a subject. 4 shows an enlarged view of a plurality of pixel areas located on the upper right side of the image sensor 110 , and the remainder of the plurality of pixel areas except for the plurality of phase sensing pixels 410 and 420 may be image pixels.

As shown in FIG. 4 , since a plurality of phase detection pixels are arranged at regular intervals, even if a user determines which part of the image sensor 110 as a focus area, a focus using a phase difference detection method using a plurality of phase detection pixels corresponding to the focus area can be set. The spacing of the phase detection pixels illustrated in FIG. 4 is only an example, and the phase detection pixels may be disposed at a narrower interval or a wider interval.

Meanwhile, a method of setting a focus using a phase sensing pixel will be described later.

5 is a diagram for explaining a method of determining a focus area by dividing an ROI according to an embodiment of the present invention.

Referring to FIG. 5 , the processor 120 may divide the ROI 10 of the image sensor 110 into a plurality of sub-ROIs. Here, the region of interest 10 may be the entire image sensor 110 or a part of the image sensor 110 . In FIG. 5 , the region of interest 10 is described as being a part of the image sensor 110 . A case in which the region of interest 10 is the entire image sensor 110 will be described later.

The processor 120 configures the first pair of the central sub-ROI 11 and the peripheral sub-ROI 12 of the region of interest 10 , the left sub-ROI 13 and the right sub-ROI of the region of interest 10 . The region of interest 10 may be divided into a second pair of ( 14 ) and a third pair consisting of an upper sub region of interest 15 and a lower sub region of interest 16 of the region of interest 10 . However, this is only an example, and the processor 120 may divide each sub-ROI so as not to overlap.

The processor 120 may calculate disparity information on a subject corresponding to each of the plurality of sub-ROIs by using the phase sensing pixels included in each of the plurality of sub-ROIs. The disparity information indicates a phase difference between objects measured by a plurality of phase detection pixels. For example, the processor 120 may calculate disparity information by using a phase sensing pixel corresponding to the central sub-ROI 11 . In this case, the number of phase sensing pixels corresponding to the central sub-ROI 11 is at least two. Disparity information is calculated by cross-correlating the image generated by the first phase detection pixels and the image generated by the second phase detection pixels corresponding to the central sub-ROI 11 . can

The processor 120 may determine a focus area within the ROI based on the disparity information. For example, the processor 120 calculates a movement distance of a lens for focusing on the sub-ROIs 11 to 16 included in the first pair to the third pair, and one of the first to third pairs. By determining the pair having the largest difference in the lens movement distances, one sub-ROI among the pair having the largest lens movement distance difference may be determined as the focal region. A method of calculating the movement distance of the lens from the disparity information will be described with reference to FIG. 6 .

The processor 120 may determine that the difference in the moving distances of any one pair of lenses among the first to third pairs is the largest. For example, the movement distance of the left sub region of interest 13 may be -100 codes from the current lens position, and the movement distance of the right sub region of interest 14 may be 100 codes from the current lens position, in this case the second pair The difference in the moving distance of the lens may be 200 codes. In this case, code is a unit indicating the position of the lens. When the difference between the moving distances of the first pair of lenses is 100 codes and the difference between the moving distances of the third pair of lenses is 134 codes, the processor 120 determines that the difference in the moving distances of the lenses of the second pair is the largest. , and either the left sub region of interest 13 or the right sub region of interest 14 may be determined as the focus region.

In this case, the large difference in the movement distance of the lenses means that the subject located in one sub-ROI of the pair of sub-ROIs is near and the subject located in the other sub-ROI is far away, and this results in perspective contention. It is said The processor 120 may select one sub-ROI from among a pair of sub-ROIs having perspective contention, but this is only an example, and the pair of sub-ROIs having the smallest difference in lens movement distance A configuration in which one sub-ROI is determined as a focus region is also possible.

The processor 120 may determine, as a focus area, a sub-ROI in which a subject is located near a pair of pairs having the largest difference in movement distance of the lenses. The position of the lens can be located at about 0 ~ 500 code, the closer to 0 code, the more distant the subject is focused, and the closer to the 500 code, the closer the focus is to the subject. By using this characteristic, the processor 120 may determine a sub-ROI near the subject. However, this is only an example, and the processor 120 may determine a sub-ROI in which the subject is far away.

6 is a diagram for explaining a method of calculating a movement distance of a lens from disparity information according to an embodiment of the present invention.

Referring to FIG. 6A , a distribution of pixels may be determined using a plurality of phase sensing pixels. For example, the distribution of pixels by the first phase sensing pixels may be the left graph 610 , and the distribution of pixels by the second phase sensing pixels may be the same as the right graph 620 .

The processor 120 may detect an image using two phase detection pixels corresponding to each of the plurality of sub-ROIs, and may cross-correlate the two images to calculate disparity information. The cross-correlation result for the two images is the second diagram of FIG. 6A , and may be in the form of a parabola convex downward.

The processor 120 may analyze the cross-correlation result and determine an x value having the lowest y value as the disparity information. That is, the processor 120 may determine the phase difference between the two images as disparity information.

Referring to FIG. 6B , the processor 120 may store disparity information on a specific subject in the storage unit 155 . A point 640 having a disparity value of 0 is a point at which a phase difference of an image sensed using two phase detection pixels is 0, and there is no need to move a lens. A point 650 having a disparity value of 1 is a point having a phase difference of 1, and in this case, the position of the lens is 400 code. The point 660 at which the disparity value is -1 is the point at which the phase difference of the image is -1, and the position of the lens is 50 codes.

The storage unit 155 may store movement distance information of a lens corresponding to the subject based on the disparity information. Such information is affected by the lens position, color temperature, and aperture value, and a method of calculating lens movement distance information reflecting these external factors will be described later.

7 and 8 are diagrams for explaining a method of calculating a moving distance and reliability information of a lens for focusing according to an embodiment of the present invention.

The processor 120 may determine a focus area in the ROI 10 by calculating a movement distance and reliability information of a lens corresponding to a position of the lens based on the disparity information. The method of determining the focal region in the region of interest 10 using the moving distance of the lens has been described above, and the method of determining the focal region in the region of interest 10 by calculating reliability information will be described later.

Referring to FIG. 7 , it is possible to know the movement distance of the lens corresponding to the position of the lens. Such information may be stored in the storage unit 155 , and the processor 120 may focus the lens by moving the position of the lens based on the information stored in the storage unit 155 . In FIG. 7 , when the current lens position is 350 code, the moving distance of the lens may be the y value 710 of the graph.

The moving distance of the lens may correspond to disparity information. For example, the moving distance of the lens may be directly proportional to the disparity information. However, this is only an exemplary embodiment, and the movement distance of the lens may be calculated based on disparity information, but may not be directly proportional to the disparity information.

Referring to FIG. 8 , the processor 120 may calculate reliability information using the cross-correlation result. The processor 120 may calculate a signal to noise (S/N) ratio with reliability by considering a value of the lowest point of the cross-correlation curve as noise and a specific point adjacent to the lowest point as a signal.

For example, in the left diagram of FIG. 8 , the processor 120 may regard 100, which is the value of the lowest point of the first cross-correlation curve 810, as noise, and 200, which is the value of a specific point adjacent to the lowest point, as a signal. have. The S/N ratio of the first cross-correlation curve 810 may be calculated as (200-100)/100=1.

Similarly, in the right diagram of FIG. 8 , the processor 120 may regard 100, which is the value of the lowest point of the second cross-correlation curve 820, as noise, and 400, which is the value of a specific point adjacent to the lowest point, as a signal. . The S/N ratio of the second cross-correlation curve 820 may be calculated as (400-100)/100=3.

The processor 120 may determine that the second cross-correlation curve 820 having an S/N ratio of 3 has high reliability. In this case, a specific point adjacent to the lowest point may be set as a point separated by the same distance from the x-axis value of the lowest point. A method of setting a focus region in the region of interest 10 from the reliability information will be described later.

9 is a diagram for explaining a method of designating a region of interest 10 according to an embodiment of the present invention.

According to FIG. 9 , the photographing apparatus may further include a display 130 . An image according to the light input through the ROI 10 and the lens may be displayed on the display 130 .

The region of interest 10 may be designated by a user, and the same may be applied when the previously set region of interest 10 is used later. However, the present invention is not limited thereto, and the region of interest 10 set at the time of initial use may be continuously used, or the region of interest 10 may be automatically set around the recognized face after recognizing a human face.

When the region of interest 10 is designated by the user, the user may set the specific region by touching the touch screen. In this case, the display 130 may be a touch screen. When the region of interest 10 is set using the touch screen, the user may draw a square trajectory on the touch screen, or set the region of interest 10 by touching two specific points. In addition, a configuration in which the size of the specific shape of the ROI 10 is changed according to the user's touch time is also possible, and the ROI 10 may be set in various other methods.

Also, the user may designate the region of interest 10 by using the button 910 . The user may move the ROI 10 of a preset size by using the button 910 . The size of the region of interest 10 may be changed by pressing one of the buttons 910 twice in succession. For example, when the right button is pressed twice in succession, the right side of the ROI 10 may be moved to change the size of the ROI 10 . Although the button 910 is illustrated as a four-way button in FIG. 9 , the present invention is not limited thereto, and a joystick-shaped button may be provided. In addition, although the region of interest 10 is indicated by a quadrangle, it is not limited thereto, and may be a circle or a triangle.

The user can designate the region of interest 10 as well as set the focus region. For example, the processor 120 may control the display 130 to display a UI indicating a pair having the largest difference in the movement distance of the lenses. Referring to FIG. 9 , the processor 120 may display the left sub-ROI 13 and the right sub-ROI 14 . In addition, when a user input for selecting one of a pair having the largest difference in movement distance of the lenses is received, the processor 120 may determine the selected sub-ROI as a focus area. The selection of the focus area is also possible by the user's touch or button input as described above.

10 is a diagram for explaining a method of determining a focus area when the area of interest 10 is the entire image sensor 110 according to an embodiment of the present invention.

Referring to FIG. 10A , the processor 120 may divide the ROI 10 into M rows and N columns of the same size. However, the present invention is not limited thereto, and may not have the same size. In addition, it is also possible to configure the division into various shapes other than a rectangle. In addition, although each divided region is illustrated as not overlapping in FIG. 10A , the present invention is not limited thereto, and may be divided in such a way that overlapping pairs exist as in FIG. 5 .

Referring to FIG. 10B , the processor 120 may calculate a movement distance of a lens for each sub-ROI. Since the method of calculating the moving distance of the lens for each area has been described above, it will be omitted.

In addition, when a difference in a movement distance of a lens with respect to an adjacent sub-ROI is less than or equal to a preset size, the processor 120 groups adjacent sub-ROIs to determine a focus area within the ROI. For example, the first group area 1010 and the second group area 1020 represent a grouped area when the difference between the moving distances is 2 or less. In FIG. 10B , the movement distance of the lens is roughly shown to explain grouping, and may have any number of different values. In addition, although it is assumed that the difference in the movement distance is 2 or less, this may also have a different value and may be set by the user.

Also, the processor 120 may group only the sub-ROIs in which the reliability of the sub-ROIs is greater than the preset reliability.

The processor 120 may determine, as the focus area, one of a group having the closest distance to the subject, a group having the highest reliability, and a group having the most sub-ROIs.

When the group closest to the subject is the reference, the processor 120 may determine the focus area by averaging the lens movement distances of the grouped sub-ROIs. Since the distance to the subject has been described above, it is omitted. However, the present invention is not limited thereto, and a group having the longest distance from the subject may be selected. Also, it is not limited to a group, and one of the sub-ROIs that are not grouped may be selected.

The same is the case with the group with the highest reliability. The method of calculating the reliability has been described above, and the average value of the reliability of a specific group may also be used as described above. Also, it is not limited to a group, and one of the sub-ROIs that are not grouped may be selected.

When the group in which the most sub-ROIs are grouped is a reference, the processor 120 may determine the focus area by determining the number of sub-ROIs in each group. However, the present invention is not limited thereto, and a configuration in which a specific number of groups is selected is also possible. Also, when the same number of groups is multiple, the processor 120 may determine the focus area by using one of the group having the closest distance to the subject and the group having the highest reliability among the multiple groups.

11 is a block diagram illustrating a circuit configuration of the photographing apparatus 100 according to an embodiment of the present invention.

Referring to FIG. 11 , the photographing apparatus 100 includes a lens 111 , an image sensor 110 , a timing generator (TG) 114 , an analog front end (AFE) 113 , a motor driver 115 , and a coupling unit. 119 , an input unit 190 , an image processing unit 170 , a communication unit 150 , a processor 120 , a display unit 130 , an SDRAM module 117 , a memory card 118 , and a USB module 116 . do.

The lens 111 is a configuration through which light reflected on a subject is incident, and includes a short focus lens, and although not shown in the drawings, the photographing apparatus 100 may further include an aperture (not shown).

The diaphragm is a configuration that adjusts the amount of light incident to the image sensor through the lens 111 . The diaphragm has a mechanical structure that can gradually increase or decrease the size of the opening so that the amount of incident light can be adjusted. Such an iris indicates the degree of opening by an iris number called an F-number, and the smaller the diaphragm value, the wider the opening, so that the amount of incident light increases and a bright image can be generated.

The image sensor 110 is configured to form an image of a subject passing through the lens 111 . The image sensor 110 includes a plurality of pixels arranged in a matrix form. Each of the plurality of pixels accumulates photocharges according to incident light, and outputs an image based on the photocharges as electrical signals. The image sensor 110 may be formed of a complementary metal oxide semiconductor (CMOS) or a charge coupled device (CCD).

In addition, the image sensor 110 is a photodiode (PD). It may include a transfer transistor TX, a reset transistor RX, and a floating diffusion node FD. The photodiode PD generates and accumulates photocharges corresponding to the optical image of the subject. The transfer transistor TX transmits the photocharge generated in the photodiode PD to the floating diffusion node FD in response to the transmission signal. The reset transistor discharges charges stored in the floating diffusion node FD in response to the reset signal. Charges stored in the floating diffusion node FD are output before the reset signal is applied. In the case of a CDS image sensor, correlated double sampling (CDS) processing is performed. Then, the ADC converts the analog signal on which CDS processing has been performed into a digital signal.

The TG (Timing Generator 114 ) outputs a timing signal for reading out pixel data of the image sensor 110 . TG 114 is controlled by processor 120 .

An analog front end (AFE) 113 samples and digitizes an electrical signal on a subject output from the image sensor 110 . AFE (Analog Front End, 113 ) is controlled by the processor 120 .

However, as described above, the AFE 113 and the TG 114 may be designed in a different configuration. In particular, when the image sensor 110 is implemented in a CMOS type, such a configuration may be unnecessary.

The motor driver 115 drives a focusing lens based on information calculated by reading out the phase difference pixel to focus. However, when the photographing apparatus 100 is implemented as a smart phone or a cellular phone, the lens for focusing may not be driven and processed through software, and the motor driver 115 may not be provided.

The image processing unit 170 image-processes raw image data under the control of the processor 120 , and writes it in the SDRAM 117 . Then, the image-processed data of the SDRAM 117 is transferred to the display 130 .

In the case of auto-focusing using a phase difference, the image processing unit 170 outputs a signal (a signal read out from a normal pixel) for generating an image among signals output from the image sensor 110 and sampled by the AFE 113 and a phase difference Separate the signal (signal read out from the phase difference pixel) for calculating .

The image processing unit 170 processes the raw image data and makes it YCbCr data. In raw image data, pixel defects are first corrected by a correction circuit (not shown). The correction circuit corrects the pixel defect by referring to the correction table, in which the address of the defective pixel is registered. For pixels matching this address, correction is performed from surrounding pixels.

The image processing unit 170 includes an OB clamp circuit (not shown) that determines the black level of the image. The image sensor 110 has an optical black (OB) region, detects an average signal value of the OB region, and determines a black level through a difference between pixel values.

Also, the image processing unit 170 performs different sensitivity ratio adjustments for each color using a sensitivity ratio adjustment circuit (not shown). The sensitivity ratio adjustment circuit adjusts the sensitivity of R, G, and B colors under a standard light source. Usually, the gain value of G is fixed to 1 and the sensitivities of R and B are adjusted accordingly.

When outputting a still image, after adjusting the sensitivity ratio, the image data is output through the output buffer. In this case, since the image is generated in an interlace method, post-processing cannot be performed immediately. On the other hand, in the case of outputting a live view image, post-processing is possible immediately because the image is generated in a progressive method. do.

Also, since the image processing unit 170 performs skip readout in which some pixel lines are read out and the remaining pixel lines are skipped using a horizontal skip readout circuit (not shown), the number of pixels of a raw image is reduced.

The image processing unit 170 adjusts white balance (WB) for image data using a WB adjustment circuit (not shown). Since the spectral distribution of illumination light varies depending on the shooting environment, it may not be displayed white even when shooting a white subject. A different gain value is given to each R, G, and B pixel to match the signal level.

Also, the image processing unit 170 performs gamma correction on the image data. A grayscale conversion suitable for the output of the display 130 is performed through gamma correction.

Also, the image processing unit 170 generates a normal color image signal including three colors per pixel from a Bayer signal of one color per pixel by using a color interpolation circuit (not shown).

In addition, a color space conversion suitable for the output is performed using a color conversion/color correction circuit (not shown), and color correction is performed. A look-up table (LUT) can be used as needed. After color conversion/color correction, the image data becomes YCbCr data.

The image processing unit 170 adjusts the size by converting the resolution using a resolution conversion circuit (not shown).

The image processing unit 170 processes a spatial filter for image data using a spatial filter circuit (not shown). Edge enhancement of the Y signal is performed, and LPF (Low Pass Filter) processing of the Cb/CR signal is performed.

Also, the image processing unit 170 performs skip readout on the Cb/Cr signal using a CbCr skip readout circuit (not shown) to convert it into YCbCr4:2:2 image data. The image data is output through the output buffer, and is written to the SDRAM 117 through the bus.

In the case of a still image, readout may be performed in an interlaced manner. In this case, since adjacent pixel lines do not exist, direct color interpolation cannot be processed. Accordingly, after the pre-processing is completed, the pixel line order is adjusted in the SDRAM 117 through the output buffer and stored in a progressive form.

However, the embodiment of the present invention is not limited to the interlace method in the case of a still image, and may be implemented to be read out in a progressive method.

On the other hand, in the case of a still image, it is necessary to generate a preview image or a thumbnail image that is displayed small after shooting. It is written by omitting data of some pixels like skip readout.

The image processing unit 170 interpolates the phase difference pixel portion into a normal pixel value using an AF signal interpolation circuit (not shown). Since the phase difference pixel is located between normal pixels, resolution degradation may occur, so that interpolation is performed using surrounding normal pixels.

Based on the above-described processing process of the image processing unit 170 , the image processing unit 170 performs the remaining images based on the attribute of one of the plurality of images acquired through the photographing apparatus 100 under the control of the processor 120 . properties can be adjusted in the same way.

Meanwhile, the signal of the phase difference pixel separated by the separation circuit (not shown) is once written to the SDRAM 117 through the first bus. Since readout and separation are performed for all of the plurality of pixels, each phase difference pixel signal is accumulated in the SDRAM 117 for a short period of time.

The stored phase difference pixel signal is input to a phase difference calculation circuit (not shown) through the first bus. The phase difference calculation circuit calculates the phase difference between phase difference pixels, and calculates the movement direction and movement amount of the focus lens. The calculated movement amount is temporarily written to a register in the phase difference calculation circuit, and is read by the processor 120 , that is, the CPU.

The processor 120 reads the calculated movement amount of the focus lens and generates a control command. The generated control command is transmitted to the motor driver 115 to drive the focus lens.

The JPEG codec compresses YCbCr data. Then, the compressed image data is recorded in the SDRAM 117 . When the processor 120 reads the compressed image data recorded in the SDRAM 117 and writes it to the memory card 118 , the image creation procedure ends.

The communication unit 150 is configured to communicate with other devices. The communication unit 150 may be implemented using various wireless communication technologies. Mainly, the communication unit 150 may include a short-distance communication module for performing direct communication without a device-to-device relay device.

The coupling unit 119 may be used to be fixed in combination with other devices, and it may be possible to perform wired communication through the coupling unit 119 . The case where it is used in combination with other devices will be described later.

The communication unit 150 may include at least one of a Wi-Fi Direct communication module, a Bluetooth module, an infrared data association (IrDA) module, a Near Field Communication (NFC) module, and a Zigbee module. can

The application of other means of communication technology is not excluded. For example, it may include any one of a cellular communication module, a 3G (3rd generation) mobile communication module, a 4G (4th generation) mobile communication module, and a 4th generation Long Term Evolution (LTE) communication module.

The USB module 116 provides an interface with an external device. The USB module 116 processes transmission and reception of image data when connected to a PC or other external device through a USB cable. In addition, it processes firmware transmission/reception for performing firmware upgrade.

The input unit 190 is configured to receive a user input. The input unit 190 may include at least one button. Also, the input unit 190 may include a touch screen positioned on the display 130 .

In addition to the shooting command or the image capturing command, the input unit 190 may receive a user command for adjusting the magnification of the captured image.

The photographing magnification adjustment command may be a user command for pressing a button included in the photographing apparatus 100 . For example, when the input unit 190 includes an up button and a down button, if a user command to press the up button is input while the live view is displayed, the live view image may be enlarged.

Also, the input unit 190 may be implemented as a touch screen, and may receive a user command for adjusting the magnification of the captured image through the display 130 .

SDRAM (Synchronous Dynamic RAM 117) is used to store images or image operations by the CPU. In an embodiment of the present invention, a DDR SDRAM capable of increasing the output by two times compared to outputting only from the rising end by allowing the output to come out from both the rising end and the falling end of the system clock may be used.

The memory card 118 may include a flash memory, and may be implemented in the form of a card detachable from the photographing apparatus 100 . In addition, the memory card 118 may store the captured image file.

12 is a view for explaining a method of correcting information on a movement distance of a lens according to an embodiment of the present invention.

12 , it is assumed that the photographing apparatus 100 uses both a contrast detection method and a phase difference detection method for focusing.

In addition, the movement distance of the lens may be information determined from disparity information calculated by the phase difference detection method with respect to the position of the lens based on the movement distance of the lens measured by the contrast detection method to focus.

As described above, when the contrast detection method is used, the speed is slow, and when the phase difference detection method is used, it may be relatively inaccurate compared to the contrast detection method. Also, based on the disparity information, the movement distance information of the lens corresponding to the subject may have an error depending on the position of the lens, the color temperature, and the aperture value.

The processor 120 uses the phase detection method to determine the focus area, and from the resultant disparity information, the movement distance information of the lens corresponding to the subject is not linear, so correction is required, and such correction is contrast detection method can be used. Specifically, by using the contrast detection method, accurate focus information on a specific subject for a specific area of the image sensor 110 may be obtained, and a movement distance of the lens according to the position of the lens may be calculated. And, based on the calculated movement distance of the lens, disparity information according to the phase detection method may be corrected to correspond to the disparity information.

12A is a view illustrating a specific region of the image sensor 110, in particular, a center region and four corner regions. The correction should be made for each area, and is not limited to five areas as shown in FIG. 12A . Also, correction is required according to the position of the subject in each area. That is, the corrected lens movement distance information may be information corrected according to the focus area and the position of the subject.

12B is an example of movement distance information of a lens with respect to the upper left corner 1210 of FIG. 12A . Before correction using the contrast detection method, the first graph 1220 for the moving distance of the lens by the phase difference detection method is not linear. This is because an error occurred depending on the position of the lens, color temperature, and aperture value. Each of these error factors may affect each or may have a composite effect. In addition, there may be various error factors in addition to the above-described error factors.

The second graph 1230 is a graph obtained by correcting the first graph 1220 using a contrast detection method. The second graph 1230 shows an almost linear result with respect to the position of the lens. Such information may be stored in the storage unit 155 .

That is, the photographing apparatus 100 is manufactured so that such information can be stored during the manufacturing process. When the phase detection method is used to determine the focus area, the processor 120 calculates a movement distance of the lens corresponding to the disparity information based on the stored information.

13 is a flowchart illustrating a control method of the photographing apparatus 100 according to an embodiment of the present invention.

Referring to FIG. 13 , first, a region of interest among the image sensors is divided into a plurality of sub regions of interest ( S1310 ). The region of interest may be an entire region or a partial region of the image sensor, and may be set by a user.

Then, disparity information on a subject corresponding to each of the plurality of sub-ROIs is calculated using the phase sensing pixels included in each of the plurality of sub-ROIs ( S1320 ).

Then, a focus area within the ROI is determined based on the disparity information (S1330).

In addition, the step of determining the focus area ( S1330 ) includes calculating the moving distance and reliability information of the lens corresponding to the position of the lens based on the disparity information, and using the moving distance and reliability information of the lens within the ROI. Determining an area of focus may be included.

In addition, the step of dividing into a plurality of sub-ROIs ( S1310 ) may include a first pair of a central sub-ROI and a peripheral sub-ROI of the ROI, and a second pair of the left sub-ROI and right sub-ROI of the ROI. The ROI may be divided into a third pair including a pair and an upper sub-ROI and a lower sub-ROI of the ROI.

In addition, the step of determining the focus area ( S1330 ) includes calculating a movement distance of a lens for focusing on sub-ROIs included in the first pair to the third pair, among the first pair to the third pair. The method may include determining a pair having the largest difference in the movement distances of the lenses, and determining a sub-ROI of one of the pairs having the largest difference in the movement distances of the lenses as the focus area.

In the step of determining the focus area ( S1330 ), displaying a UI indicating the pair having the largest difference in the movement distance of the lenses, and receiving a user input for selecting one of the pair having the largest difference in the movement distance of the lenses The method may further include the step of: and determining the selected sub-ROI as a focus area.

In addition, in the step of dividing the ROI into a plurality of sub-regions ( S1310 ), the ROI is divided into M rows and N columns of the same size, and the step of determining the focal region ( S1330 ) includes lenses for adjacent sub-regions of interest. When the difference in the movement distance of ' is equal to or less than a preset size, a focal region within the ROI may be determined by grouping adjacent sub-ROIs.

In the determining of the focus area ( S1330 ), one group among a group having the closest distance to the subject, a group having the highest reliability, and a group having the most sub-ROIs grouped may be determined as the focus area.

In addition, in the step of determining the focal region ( S1330 ), only sub-ROIs for which the reliability of the sub-ROI is greater than a preset reliability may be grouped.

In addition, the movement distance of the lens may be information determined from disparity information calculated by the phase difference detection method with respect to the position of the lens based on the movement distance of the lens measured by the contrast detection method for focusing.

Also, in the step of calculating the disparity information ( S1320 ), an image is sensed using two phase detection pixels corresponding to each of the plurality of sub-ROIs, and the disparity information is calculated by cross-correlating the two images. can do.

According to various embodiments of the present disclosure as described above, the photographing apparatus may more rapidly calculate information about a subject, and automatically determine a focus area accordingly, thereby improving user satisfaction.

Meanwhile, the methods according to various embodiments may be programmed and stored in various storage media. Accordingly, the methods according to the above-described various embodiments may be implemented in various types of electronic devices executing a storage medium.

Specifically, according to an embodiment of the present invention, dividing the region of interest in the image sensor into a plurality of sub regions of interest, each of the plurality of sub regions of interest using phase sensing pixels included in each of the plurality of sub regions of interest A non-transitory computer readable medium storing a program for sequentially calculating disparity information on a subject corresponding to , and determining a focus area in a region of interest based on the disparity information may be provided.

The non-transitory readable medium refers to a medium that stores data semi-permanently, rather than a medium that stores data for a short moment, such as a register, cache, memory, and the like, and can be read by a device. Specifically, the various applications or programs described above may be provided by being stored in a non-transitory readable medium such as a CD, DVD, hard disk, Blu-ray disk, USB, memory card, ROM, and the like.

In addition, although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above, and the technical field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims In addition, various modifications are possible by those of ordinary skill in the art, and these modifications should not be individually understood from the technical spirit or perspective of the present invention.

100: photographing device 110: image sensor
120: processor 130: display
140: user interface unit 150: communication unit
155: storage unit 160: audio processing unit
170: image processing unit 180: speaker
181: button 182: microphone

Claims (20)

an image sensor including a plurality of image pixels for sensing an image by collecting light input through a lens, and a plurality of phase sensing pixels for detecting a phase; and
A region of interest among the image sensor is divided into a plurality of sub-regions, and a phase detection pixel included in each of the plurality of sub-regions of interest is used to detect a subject corresponding to each of the plurality of sub-regions of interest. a processor that calculates disparity information and determines a focus area within the ROI based on the disparity information;
The processor is
calculating a movement distance of the lens corresponding to the position of the lens based on the disparity information;
and determining a focus area within the ROI based on grouping sub-ROIs in which a difference in movement distance of the lens with respect to an adjacent sub-ROI among the plurality of sub-ROIs is less than or equal to a preset size. According to claim 1,
The processor is
and determining a focus area within the ROI by calculating movement distance and reliability information of the lens based on the disparity information. According to claim 1,
The processor is
A first pair consisting of a central sub-region of interest and a peripheral sub-region of the region of interest, a second pair consisting of a left sub-region and a right sub-region of the region of interest, and an upper sub-region of interest and a lower sub-region of the region of interest and dividing the region of interest into a third pair of regions. 4. The method of claim 3,
The processor is
calculating a movement distance of the lens for focusing on sub-ROIs included in the first pair, the second pair, and the third pair, and moving the lens among the first pair, the second pair, and the third pair A photographing apparatus, characterized in that by determining a pair having the largest distance difference, and determining a sub-ROI of one of the pairs having the largest lens movement distance difference as a focus area. 5. The method of claim 4,
display; and
It further includes; a user interface unit for receiving a user input;
The processor is
The display is controlled to display a UI indicating the pair having the largest difference in the movement distance of the lenses, and when a user input for selecting one of the pair having the largest difference in the movement distance of the lenses is received, the selected sub-ROI A photographing apparatus, characterized in that it is determined as a focus area. delete 3. The method of claim 2,
The processor is
The photographing apparatus of claim 1, wherein one of the group having the closest distance to the subject, the group having the highest reliability, and the group having the most sub-ROIs is determined as the focus area. 3. The method of claim 2,
The processor is
and grouping only the sub-ROIs in which the reliability of the sub-ROI is greater than a preset reliability. According to claim 1,
The moving distance of the lens,
The photographing apparatus, characterized in that the information is determined from the disparity information calculated by a phase difference detection method (Phase Auto Focus) with respect to the position of the lens. According to claim 1,
The processor is
An image pickup apparatus characterized in that an image is sensed using two phase detection pixels corresponding to each of the plurality of sub-ROIs, and disparity information is calculated by cross-correlating the two images. . A method of controlling a photographing apparatus having an image sensor including a plurality of image pixels for sensing an image by collecting light input through a lens, and a plurality of phase sensing pixels for detecting a phase,
dividing a region of interest in the image sensor into a plurality of sub regions of interest;
calculating disparity information on a subject corresponding to each of the plurality of sub-ROIs by using the phase sensing pixels included in each of the plurality of sub-ROIs; and
Determining a focal region within the ROI based on the disparity information;
Determining the focus area comprises:
calculating a movement distance of the lens corresponding to the position of the lens based on the disparity information; and
determining a focal region within the ROI based on grouping of sub-ROIs in which a difference in movement distance of the lens with respect to an adjacent sub-ROI among the plurality of sub-ROIs is less than or equal to a preset size; A control method comprising a. 12. The method of claim 11,
Determining the focus area comprises:
calculating the moving distance and reliability information of the lens based on the disparity information; and
and determining a focus area within the ROI by using the moving distance and reliability information of the lens. 12. The method of claim 11,
The dividing into the plurality of sub-regions of interest comprises:
A first pair consisting of a central sub-region of interest and a peripheral sub-region of the region of interest, a second pair consisting of a left sub-region and a right sub-region of the region of interest, and an upper sub-region of interest and a lower sub-region of the region of interest and dividing the region of interest into a third pair of regions. 14. The method of claim 13,
Determining the focus area comprises:
calculating a movement distance of the lens for focusing on sub-ROIs included in the first pair, the second pair, and the third pair;
determining a pair having the largest difference in lens movement distance among the first pair, the second pair, and the third pair; and
and determining, as a focus region, one sub-ROI of a pair having the largest difference in movement distance of the lenses. 15. The method of claim 14,
Determining the focus area comprises:
displaying a UI indicating a pair having the largest difference in moving distances of the lenses;
receiving a user input for selecting one of the pairs having the largest difference in the moving distances of the lenses; and
and determining the selected sub-region of interest as a focus region. delete 13. The method of claim 12,
Determining the focus area comprises:
A control method, characterized in that one of a group having the closest distance to the subject, a group having the highest reliability, and a group having the most sub-ROIs is determined as a focus area. 13. The method of claim 12,
Determining the focus area comprises:
A control method, characterized in that grouping only the sub-ROIs in which the reliability of the sub-ROI is greater than a preset reliability. 12. The method of claim 11,
The moving distance of the lens,
The control method, characterized in that the information determined from the disparity information calculated by a phase difference detection method (Phase Auto Focus) with respect to the position of the lens. 12. The method of claim 11,
Calculating the disparity information comprises:
A control method, characterized in that an image is sensed using two phase detection pixels corresponding to each of the plurality of sub-ROIs, and disparity information is calculated by cross-correlating the two images. .

Images