JP5256847B2 - Imaging device - Google Patents

Description

The present invention relates to an imaging device.

  An image processing apparatus is known that extracts a background region from an image by extracting a region that is highly likely to be a background based on the luminance distribution of the image and determining the color gamut of this region (Patent Document 1). ).

JP 2002-368882 A

However, when image analysis is performed using the luminance distribution of the image, there is a problem that accurate luminance cannot be obtained for the peripheral portion of the image depending on the characteristics of the optical system, and accurate image analysis cannot be performed.

The problem to be Solved by the Invention is to provide a imaging device that can perform accurate image analysis.

  The present invention solves the above problems by the following means. In addition, although the code | symbol corresponding to drawing which shows embodiment of this invention is attached | subjected and demonstrated, this code | symbol is only for making an understanding of invention easy, and is not the meaning which limits invention.

An imaging apparatus according to the present invention includes: a first imaging unit that captures an image by an imaging optical system; a second imaging unit that is different from the first imaging unit that acquires first image information and second image information; Corresponding to the background based on the first image information corrected by the correction means and the correction means for correcting the luminance for the first image information and not correcting the luminance for the second image information First processing means for extracting an area, second processing means for extracting an area corresponding to a face from color information included in the second image information, using the extraction result of the first processing means, and the second A focus adjustment control means for determining an area for detecting a focus adjustment state by tracking an area corresponding to the face extracted by a processing means, and controlling a focus adjustment state of the imaging optical system. Features.

In the above invention, the focus adjustment control unit sets an image of the region extracted by the second processing unit as a reference image, sets a predetermined peripheral region including the reference image and wider than the reference image, and the second imaging The third image information obtained by the means after a predetermined time from the second image information and the reference image are compared based on the color information and the luminance, and the reference image is included in the third image information. When there is matching image information, the position information of the matching image information can be obtained.

In the above invention, the focus adjustment control unit determines a focus detection area based on the position information obtained by the focus detection unit, and the imaging optics based on the determined focus adjustment state of the focus detection area. A defocus amount of the system can be obtained, and the imaging optical system can be moved to a focus position based on the defocus amount.

An imaging apparatus according to the present invention corrects luminance for the first image information, imaging means for acquiring first image information and second image information by capturing an image by an imaging optical system, Correction means that does not correct the luminance of the second image information, first processing means that extracts a region corresponding to a background based on the first image information corrected by the correction means, and the first processing A second processing unit that extracts a region corresponding to a face from the second image information using the extraction result of the unit; and a focus adjustment state of the imaging optical system using the extraction result of the second processing unit. And a focus adjustment control means for controlling.

In the above invention, the focus adjustment control unit is configured to adjust the focus adjustment state of the imaging optical system after the first image information is acquired by the imaging unit and before the second image information is acquired by the imaging unit. Can be configured to control.

Further, in the above invention, the focus adjustment control means can be configured to determine an area for detecting a focus adjustment state by tracking an area corresponding to the face extracted by the second processing means. .

  According to the above invention, the accuracy of image analysis can be improved.

In the following, an embodiment in which the above invention is applied to a single-lens reflex digital camera will be described with reference to the drawings. However, the above-described invention can also be applied to a silver salt film camera, a compact camera, and other imaging devices.

FIG. 1 is a block diagram showing a single-lens reflex digital camera 1 according to the present embodiment. The illustration and description of a general configuration of the camera other than the configuration related to the image analysis apparatus and the imaging apparatus of the invention are partially omitted. To do.

The single-lens reflex digital camera 1 of this embodiment (hereinafter simply referred to as the camera 1) includes a camera body 100 and a lens barrel 200, and the camera body 100 and the lens barrel 200 are detachably coupled.

The lens barrel 200 incorporates a photographing optical system including a lens group 210 including a focus lens 211 and a zoom lens 212, an aperture device 220, and the like.

The focus lens 211 is provided so as to be movable along the optical axis L <b> 1, and its position is adjusted by the focus lens driving motor 230 while its position is detected by the focus lens encoder 260. Then, the position information of the focus lens 211 detected by the focus lens encoder 260 is transmitted to the lens drive control unit 165 described later via the lens control unit 250. The focus lens drive motor 230 is driven by a drive signal transmitted from the lens drive control unit 165 via the lens control unit 250 in accordance with a drive amount and a drive speed calculated based on a focus detection result to be described later. . Further, the focus lens drive motor 230 is driven by a drive signal transmitted from the lens control unit 250 at a position corresponding to the focal length of the zoom lens 212 described later.

  The zoom lens 212 is provided so as to be movable along the optical axis L <b> 1, and its position is adjusted by the zoom lens driving motor 270 while its position is detected by the zoom lens encoder 280. The position of the zoom lens 212 is adjusted by operating a zoom button provided on the operation unit 150. Then, the position information of the zoom lens 212 detected by the zoom lens encoder 280 is transmitted to the lens control unit 250.

The aperture device 220 is adjustable in its aperture diameter around the optical axis L1 in order to limit the amount of light beam that passes through the photographing optical system and reaches the image sensor 110. The aperture diameter is adjusted by the aperture device 220 by, for example, transmitting a signal corresponding to the aperture value calculated in the automatic exposure mode from the camera control unit 170 to the aperture drive unit 240 via the lens control unit 250. . The aperture diameter is adjusted by a manual operation by the operation unit 150 provided in the camera body 100, and a signal corresponding to the set aperture value is transmitted from the camera control unit 170 to the aperture drive unit 240 via the lens control unit 250. This is also done by sending it.

The lens barrel 200 is provided with a lens control unit 250. The lens control unit 250 includes a microprocessor and peripheral components such as a memory, and is electrically connected to the camera control unit 170. The lens control unit 250 receives information such as a defocus amount and an aperture control signal from the camera control unit 170, and a camera. The lens information is transmitted to the controller 170.

On the other hand, the camera body 100 includes a mirror system 120 for guiding the light flux from the subject to the image sensor 110, the finder 135, the photometric sensor 137, and the focus detection module 161. The mirror system 120 includes a quick return mirror 121 that rotates by a predetermined angle between the observation position and the photographing position of the subject around the rotation axis 123, and the quick return mirror 121 that is pivotally supported by the quick return mirror 121. And a sub mirror 122 that rotates in accordance with the rotation. In FIG. 1, a state where the mirror system 120 is at the observation position of the subject is indicated by a solid line, and a state where the mirror system 120 is at the photographing position of the subject is indicated by a two-dot chain line.

The mirror system 120 is inserted on the optical path of the optical axis L1 in the state where the subject is in the observation position, while rotating so as to retract from the optical path of the optical axis L1 in the state where the subject is in the photographing position.

The quick return mirror 121 is composed of a half mirror, and in a state where the subject is at the observation position, the quick return mirror 121 reflects a part of the light flux (optical axes L2 and L3) from the subject (optical axis L1). Then, the light is guided to the finder 135 and the photometric sensor 137, and a part of the light beam (optical axis L4) is transmitted and guided to the sub mirror 122. On the other hand, the sub mirror 122 is configured by a total reflection mirror, and guides the light beam (optical axis L4) transmitted through the quick return mirror 121 to the focus detection module 161.

Therefore, when the mirror system 120 is at the observation position, the light flux (optical axis L1) from the subject is guided to the finder 135, the photometric sensor 137, and the focus detection module 161, and the subject is observed by the photographer and exposure calculation is performed. And the focus adjustment state of the focus lens 211 is detected. Then, when the photographer fully presses the release button, the mirror system 120 rotates to the photographing position, and all the luminous flux (optical axis L1) from the subject is guided to the image sensor 110, and the photographed image data is stored in a memory (not shown). To do.

  The focus detection module 161 is a focus detection element for executing automatic focusing control by a phase difference detection method using subject light, and the imaging surface of the imaging element 110 of the light beam (optical axis L4) reflected by the sub-mirror 122. It is fixed at an optically equivalent position.

FIG. 2 is a diagram illustrating a configuration example of the focus detection module 161 illustrated in FIG.

The focus detection module 161 of this example includes a condenser lens 161a, a diaphragm mask 161b having a pair of apertures, a pair of re-imaging lenses 161c, and a pair of line sensors 161d. The focus adjustment state is detected by obtaining a phase shift of a pair of image signals obtained by receiving a pair of light fluxes passing through the region by a line sensor 161d by a known correlation calculation.

As shown in FIG. 2, when the subject P is imaged on the equivalent surface (scheduled imaging surface) 161e of the image sensor 110, the focused state is obtained. However, the focus lens 211 moves in the direction of the optical axis L1, and the result is as follows. If the image point shifts from the equivalent surface 161e toward the subject (referred to as a front pin) or shifts toward the camera body 100 (referred to as a rear pin), a focus shift state occurs.

When the imaging point of the subject P is shifted from the equivalent surface 161e toward the subject, the interval W between the pair of image signals detected by the pair of line sensors 161d becomes shorter than the interval W in the focused state, and vice versa. If the imaging point of the subject image P is shifted to the camera body 100 side, the interval W between the pair of image signals detected by the pair of line sensors 161d becomes longer than the interval W in the focused state.

That is, in the in-focus state, the image signals detected by the pair of line sensors 161d overlap with the center of the line sensor, but in the out-of-focus state, each image signal is shifted from the center of the line sensor, that is, the phase difference is increased. Therefore, focusing is performed by moving the focus lens 211 by an amount corresponding to the phase difference (deviation amount).

Returning to FIG. 1, the AF-CCD control unit 162 controls the gain and accumulation time of the line sensor 161 d of the focus detection module 161 in the autofocus mode, and stores information on the focus detection area selected as the focus detection position. A pair of image signals received from the camera control unit 170 and detected by the pair of line sensors 161 d corresponding to the focus detection area are read and output to the defocus calculation unit 163.

The defocus calculation unit 163 converts the shift amount of the pair of image signals sent from the AF-CCD control unit 162 into a defocus amount ΔW, and outputs this to the lens drive amount calculation unit 164.

The lens drive amount calculation unit 164 calculates a lens drive amount Δd corresponding to the defocus amount ΔW based on the defocus amount ΔW sent from the defocus calculation unit 163, and supplies this to the lens drive control unit 165. Output.

The lens drive control unit 165 sends a drive command to the lens drive motor 230 based on the lens drive amount Δd sent from the lens drive amount calculation unit 164, and moves the focus lens 211 by the lens drive amount Δd.

The image sensor 110 is provided on the camera body 100 on the optical axis L1 of the light beam from the subject and at a position that is a planned focal plane of the photographing optical system including the lens group 210, and a shutter 111 is provided on the front surface thereof. ing. The imaging element 110 is a two-dimensional array of a plurality of photoelectric conversion elements, and can be configured by a two-dimensional CCD image sensor, a MOS sensor, a CID, or the like. The electrical image signal photoelectrically converted by the image sensor 110 is subjected to image processing by the camera control unit 170 and then stored in a memory (not shown). Note that the memory for storing the photographed image can be constituted by a built-in memory or a card-type memory.

On the other hand, the light flux from the subject reflected by the quick return mirror 121 forms an image on a focusing screen 131 disposed on a surface optically equivalent to the image sensor 110, and the photographer passes through the pentaprism 133 and the eyepiece 134. Led to the eyeball. At this time, the transmissive liquid crystal display 132 superimposes and displays a focus detection area mark on the subject image on the focusing screen 131 and relates to shooting such as the shutter speed, aperture value, and number of shots in an area outside the subject image. Display information. Thereby, in the shooting preparation state, the subject, its background, shooting related information, and the like can be observed through the finder 135.

The operation unit 150 is a shutter release button, a zoom button, and an input switch for the photographer to set various operation modes of the camera 1, and switches between automatic exposure mode / manual exposure mode, auto focus mode / manual focus mode, Even in the auto focus mode, switching between the one-shot mode / continuous mode can be performed.

In addition, the shutter release button is turned on when the shutter release button is fully pressed, but in addition to this, when the button is pressed halfway in the auto focus mode, the focusing operation of the focus lens is turned on, and when the button is released, it is turned off. . A single / continuous shooting setting button is also included, and a predetermined number of images can be taken per second when the release button is fully pressed in the continuous shooting mode.

The zoom button also includes a W button that zooms to the wide-angle side and a T button that zooms to the telephoto side. When the W button is pressed, the zoom lens drive motor 270 is driven to shorten the focal length of the zoom lens 212. When the T button is pressed, the zoom lens driving motor 270 is driven so as to increase the focal length of the zoom lens 212. Various modes set by the operation unit 150 are transmitted to the camera control unit 170.

The camera body 100 is provided with a camera control unit 170. The camera control unit 170 includes a microprocessor and peripheral components such as a memory, and is electrically connected to the lens control unit 250. The camera control unit 170 receives lens information from the lens control unit 250. Information such as an aperture control signal is transmitted. The camera control unit 170 reads out image information from the image sensor 110 as described above, performs predetermined information processing as necessary, and outputs the information to a memory (not shown). The camera control unit 170 controls the entire camera 1 such as correction of captured image information and detection of a focus adjustment state and an aperture adjustment state of the lens barrel 200.

In the vicinity of the eyepiece lens 134, a photometric lens 136 and a photometric sensor 137 are provided to receive part of the subject light imaged on the focusing screen 131.

The photometric sensor 137 of this example is composed of a two-dimensional color CCD image sensor or the like, and outputs a photometric signal corresponding to the luminance of the received light flux to the camera control unit 170 for each predetermined pixel group, and an image sensor for photographing. An exposure value of 110 is calculated. A photometric signal for each pixel or predetermined pixel group by the photometric sensor 137 is output to the camera control unit 170 and used for analysis and recognition of a shooting scene, and the position of a focus adjustment target based on luminance and color. Is used for various image analysis processes. Hereinafter, the image analysis processing of the camera 1 of this example will be described.

  3A to 3E are front views showing the photometric sensor 137 and are diagrams for explaining an image analysis example of the camera 1 of this example. The photometric sensor 137 of this example is a two-dimensional color CCD image sensor having i × j light receiving portions (pixels) 137a with i rows in the horizontal direction and j columns in the vertical direction. ] [1], the light receiving part 137a of i rows and j columns is referred to as a light receiving part [i] [j].

  FIG. 4A is a flowchart showing an operation example of the camera 1 of this example, and FIG. 4B is a flowchart showing a subroutine of step S7 in FIG. 4A.

  In the camera 1 of this example, a process of extracting the background area of the subject from the image information captured by the photometric sensor 137 and a process of extracting the face area of the subject (person) from the image information captured by the photometric sensor 137 are performed. Run. Hereinafter, as shown in FIG. 3A, a case where a scene with a person 137 </ b> A on the center left side, a tree 137 </ b> B on the center right side, and a road 137 </ b> C in front is taken as an example.

  First, when the main power supply of the camera 1 is turned on, images by the photographing optical system 210 are acquired at predetermined intervals using the photometric sensor 137 (step S1).

The luminance information of the image acquired in step S1 is sent to the camera control unit 170, and the camera control unit 170 executes light amount correction processing based on the optical characteristics of the photographing optical system 210 based on the luminance information (step S2).

  Here, the luminance output of the light receiving unit [i] [j] of the image acquired in step S1 is Vy [i] [j], and the output of each RGB color of the light receiving unit [i] [j] is Vr [i]. [J], Vg [i] [j], Vb [i] [j], and the constants for calculating the luminance value by synthesizing the RGB outputs of each light receiving unit are Rmix, Gmix, and Bmix, respectively. The luminance output Vy [i] [j] before the correction process is expressed by the following formula 1.

<< Formula 1 >>
Vy [i] [j] =
Rmix × Vr [i] [j] + Gmix × Vg [i] [j] + Bmix × Vb [i] [j]
In the light amount correction process of step S2, the luminance output Vy [i] [j] of the above equation 1 is corrected based on the following equation 2. As a result, the light amount is corrected for a wide-angle lens or the like that may cause a decrease in the light amount in the peripheral portion, and the background area extraction accuracy in the subsequent step S3 is improved.

In Equation 2, VyZ [i] [j] is a luminance output after correction, and Kadj [i] [j] is a coefficient for performing light amount correction on each light receiving unit 137a. The corrected luminance output VyZ [i] [j] is shown in FIG. 3B.

<< Formula 2 >>
VyZ [i] [j] = Vy [i] [j] × Kadj [i] [j]
When the luminance output of each light receiving unit 137a is corrected in step S2, for each column of the corrected luminance output VyZ [i] [j] (FIG. 3B), the background region is calculated based on the following equations 3 and 4. Make a decision.

<< Formula 3 >>
| Log ₂ (VyZ [i] [j]) − log ₂ (VyZ [i] [1]) | <B
<< Formula 4 >>
M1 [i] [j-1] ≠ 0
In Equation 3 above, B is a determination threshold obtained in advance by experiments, log ₂ (VyZ [i] [j]) is the logarithm of the luminance output VyZ [i] [j] with _{2 as} the base, and log ₂ (VyZ [ i] [1]) is a logarithm of the luminance output VyZ [i] [1] with 2 as the base, and all units are steps used in an APEX (Additive System of Photographic Exposure) operation or the like.

In Equation 4, M1 is a flag for determining whether or not it is a background region. The initial value of M1 [i] [1] is 1, and the initial value of M1 [i] [j] that satisfies j ≠ 1 is 0. It is.

  Here, it can be said that there is a high possibility that the object field area corresponding to the light receiving unit 137a in the uppermost row [i] [1] of the photometric sensor 137 is the background region, and thus the light receiving in the uppermost row [i] [1]. For the luminance output VyZ [i] [1] of the unit 137a, the luminance region within the determination threshold B is set as the luminance region of the background region. Then, the determination flag M1 [i] of the light receiving unit 137a that satisfies the above expression 3 when j is assigned to j of the luminance output VyZ [i] [j] in order from the smallest j as j = 2, 3, 4,. [J] is replaced with an initial value 0 to 1.

  When the calculation is completed up to the lowest row of the photometric sensor 137, the light receiving unit 137a having M1 [i] [j] = 1 is extracted. The extracted background region 137D is shown in FIG. 3C. The information of the background region 137D extracted in this way can be used as information that determines, for example, selection of a focus detection area and exposure control.

  Next, the face area of the person 137A is extracted from the captured image of the scene. That is, in step S4, images by the photographing optical system 210 are acquired at predetermined intervals using the photometric sensor 137 as in step S1.

In step S5, the focus adjustment state in the predetermined focus detection area is detected by the focus detection module 161, and the defocus calculation unit 163, the lens drive amount calculation unit 164, the lens drive control unit 165, the lens control unit 250, and the focus lens drive. The focus lens 211 is driven to the in-focus position by the procedure described above via the motor 230, and the shooting distance is detected by detecting the position by the focus lens encoder 260.

  In step S6, a face area is extracted. Here, the face area is extracted on the assumption that the face area of the person 137A exists in an area other than the background area (see FIG. 3C) extracted in step S3, but the entire image acquired in step S4 is extracted. The following processing can also be executed.

  First, the hue H is calculated for the image of the region excluding the background region 137D extracted in step S3. The hue H is an output of R (red) when the RGB output of each light receiving unit 137a of the photometric sensor 137 is R, G, B, the maximum value is MAX, and the minimum value is MIN. In this case, hue H = 60 × (GB) / (MAX−MIN). Similarly, when MAX is an output of G (green), hue H = 120 + 60 × (BR) / ( MAX−MIN), and when MAX is an output of B (blue), hue H = 240 + 60 × (RG) / (MAX−MIN).

  Next, when the hue of the light receiving unit [i] [j] is H [i] [j] and the constant for setting the hue range of the human skin is Hloconst, Hhiconst (Hloconst, Hhiconst is 0 to 30 °, for example) Then, the light receiving part [i] [j] satisfying the following formula 5 is extracted. FIG. 3D shows regions 137F1 and 137F2 extracted as face region candidates satisfying Expression 5.

<< Formula 5 >>
Hloconst <H [i] [j] <Hhiconst
Next, the camera control unit 170 obtains the number Fwidth (number of pixels) of the light receiving units 137a of the photometric sensor 137 corresponding to the face width by the following formula 6. In Equation 6, Ftyp is a constant corresponding to the actual human face width, f is the focal length of the photographing optical system 210, D is the photographing distance in the predetermined focus detection area detected in step S5, and p is a photometric sensor. The pitch of 130 light receiving portions 137a.

≪Formula 6≫
Fwidth = (Ftyp × f) / (D × p)
The above formula 6 is a relational expression in which the image magnification is not changed while the light beam passes from the quick return mirror 121 through the photometric lens 136, but the magnification is also used in an optical system in which the image magnification is changed. The number of light receiving portions Fwidth can be obtained by taking into consideration a relational expression (for example, the pitch p is set to an appropriate value).

Next, the number of light receiving portions Fwidth obtained by the above equation 6 is compared with the number of light receiving portions of the face area candidates 137F1 and 137F2 extracted by the above equation 5, and if they match, the region is determined as a face region. As for the two face area candidates 137F1 and 137F2 shown in FIG. 3D, only one face area candidate 137F1 matches the number of light receiving portions Fwidth, so that this area 137F1 is set as a face area detection result as shown in FIG. 3E.

  As described above, the face region 137F1 is extracted. However, since the hue is more important than the luminance in the image analysis process, the light amount correction performed in step S2 is not performed. Therefore, the calculation load is reduced.

  The information on the face area 137F1 extracted in step S6 is used for focus detection in the next step S7, for example. Here, it is assumed that a process of focusing on the extracted face area 137 while tracking the position of the face area 137 is executed.

  That is, first, the subject area set in step S71 of FIG. 4A, for example, the image of the face area 137F1 extracted in step S6 is extracted to generate a template image. Next, in step S72, a predetermined area around the face area 137F1 that is wider than this is set, and image information corresponding to the peripheral area after a predetermined time has elapsed is generated based on the output signal of the photometric sensor 137. Compare with the generated template image. The image information used in this comparison is the color information and the luminance value detected by the photometric sensor 137, and the degree of matching between the template image and the surrounding image is evaluated as the similarity and the other matches the surrounding area. Whether or not there is an area to be evaluated is evaluated as reliability.

In step S73, matching processing between the image of the peripheral area and the template image is executed. When matching is performed, the process proceeds to step S74, and the two-dimensional coordinates of the matching area among the images of the peripheral area are calculated and obtained. If there is no matching, the process returns to step S71 and the above processing is repeated.

  When matching with the template image and the two-dimensional coordinates of the area are obtained, the camera control unit 170 holds the matching information and the coordinate information. Further, as a result of the matching processing, the camera control unit 170 also holds the similarity and reliability between the template image and the peripheral image.

  Next, a focus detection area for focus detection is determined based on the two-dimensional coordinates of the matched areas in step S75, and the focus adjustment state in this focus detection area is detected by the focus detection module 161. In step S76, the focus lens 211 is moved to the in-focus position by the above-described procedure via the defocus calculation unit 163, the lens drive amount calculation unit 164, the lens drive control unit 165, the lens control unit 250, and the focus lens drive motor 230. Drive to.

  In step S77, the in-focus state is determined. If the in-focus state is within the predetermined threshold, the process proceeds to step 8 in FIG. 4A. If the in-focus state is out of the predetermined threshold, the process returns to step S71 and the above processing is repeated.

  Returning to FIG. 4A, when the release button is pressed in step S8, the quick return mirror 121 is rotated to the retracted position and the shutter 111 is opened, and the image of the subject that has passed through the photographing optical system 210 is captured by the image sensor 110 (step). S9). The above processing continues until the main power is turned off (step S10).

  As described above, according to the camera 1 of the present embodiment, the light amount correction process is executed in the image analysis process that extracts the background area mainly based on the luminance information, whereas the face area is mainly based on the color information. In the image analysis process for extracting the light amount, the light amount correction process is not executed, so that the calculation load can be reduced.

It is a block diagram which shows the camera which concerns on embodiment of invention. It is a figure which shows the focus detection module of FIG. FIG. 3 is a diagram (part 1) for explaining an image analysis example of the camera of FIG. 1; FIG. 3 is a second diagram for explaining an image analysis example of the camera of FIG. 1; FIG. 4 is a third diagram illustrating an image analysis example of the camera in FIG. 1. FIG. 4 is a diagram (part 4) for explaining an image analysis example of the camera of FIG. 1; FIG. 6 is a diagram (No. 5) for describing an image analysis example of the camera of FIG. 1; 3 is a flowchart illustrating an operation example of the camera of FIG. 1. It is a flowchart which shows the subroutine of FIG.4A step S7.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Single-lens reflex digital camera 100 ... Camera body 110 ... Image pick-up element 136 ... Photometry lens 137 ... Photometry sensor 161 ... Focus detection module 170 ... Camera control part 200 ... Lens barrel 210 ... Lens group 211 ... Focus lens 212 ... Zoom lens 220 ... Aperture device 230 ... Focus lens drive motor 240 ... Aperture drive device 250 ... Lens control unit 260 ... Focus lens encoder

Claims (7)

First imaging means for capturing an image by the imaging optical system;
A second imaging means different from the first imaging means for obtaining the first image information and the second image information;
Correction means for correcting the luminance of the first image information and not correcting the luminance of the second image information;
First processing means for extracting a region corresponding to a background based on the first image information corrected by the correction means;
Second processing means for extracting a region corresponding to a face from color information included in the second image information using an extraction result obtained by the first processing means;
A focus adjustment control means for determining an area for detecting a focus adjustment state by tracking an area corresponding to the face extracted by the second processing means, and for controlling a focus adjustment state of the imaging optical system; An imaging apparatus comprising: The focus adjustment control means includes:
An image of the region extracted by the second processing means is set as a reference image;
Set a predetermined peripheral area including the reference image and wider than this,
Comparing the third image information acquired by the second imaging means after a predetermined time from the second image information and the reference image based on the color information and the luminance;
The imaging apparatus according to claim 1, wherein when there is image information that matches the reference image in the third image information, position information of the matching image information is obtained. The focus adjustment control means includes:
Determine a focus detection area based on the position information obtained by the focus detection means, obtain a defocus amount of the imaging optical system based on the focus adjustment state of the determined focus detection area,
The imaging apparatus according to claim 1, wherein the imaging optical system is moved to a focus position based on the defocus amount. Imaging means for acquiring first image information and second image information by capturing an image by an imaging optical system;
Correction means for correcting the luminance of the first image information and not correcting the luminance of the second image information;
First processing means for extracting a region corresponding to a background based on the first image information corrected by the correction means;
Second processing means for extracting a region corresponding to a face from the second image information using the extraction result obtained by the first processing means;
An imaging apparatus comprising: a focus adjustment control unit that controls a focus adjustment state of the imaging optical system using an extraction result obtained by the second processing unit. The focus adjustment control unit controls a focus adjustment state of the imaging optical system after the first image information is acquired by the imaging unit and before the second image information is acquired by the imaging unit. Item 5. The imaging device according to Item 4. The imaging apparatus according to claim 5, wherein the focus adjustment control unit determines an area for detecting a focus adjustment state by tracking a region corresponding to the face extracted by the second processing unit. 7. The correction unit according to claim 4, wherein the correction unit corrects a light amount decrease in a peripheral portion of the image with respect to the first image information and does not correct a light amount decrease in a peripheral portion of the image with respect to the second image information. The imaging device according to one item.

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