JP2016032180A - Imaging apparatus, control method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acquire an image in which influences of blurring of subjects are suppressed, in the state where a plurality of subjects are focused.SOLUTION: An imaging apparatus is configured to acquire a first image for generating an image focusing the plurality of subjects by continuously performing imaging with different lens positions of a focus lens. The imaging apparatus includes: evaluation value acquisition means for acquiring a first evaluation value based on a second image acquired for setting the lens position and a second evaluation value based on a first image acquired on the basis of the first evaluation value; determination means for determining whether a difference between the first evaluation value and the second evaluation value based on the first image and the second image which are acquired with the same lens position is greater than a first value; and first control means by which, in the case where it is determined that the difference is greater than the first value, control is performed in such a manner that a pixel region corresponding to the subject that is focused at a maximum, in the second image is not used when generating the image focusing the plurality of subjects.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an imaging apparatus that continuously images a subject by changing the lens position of a focus lens, and a control method and program thereof.

  2. Description of the Related Art Conventionally, there is an image pickup apparatus that includes a photographing lens including a focus lens and performs so-called focus bracket photographing in which a subject is continuously photographed by changing the lens position of the focus lens.

  Patent Document 1 proposes a camera that performs focus bracket shooting by automatically setting the focus position and the number of shots based on the subject distance from the camera to the subject and the aperture value.

JP 2004-333924 A

  It is known to synthesize a plurality of images acquired by the above-described focus bracket shooting to acquire an image in which a plurality of subjects are focused (hereinafter referred to as an omnifocal image).

  However, Patent Document 1 does not mention a case where an image in which a subject is blurred by focus bracket shooting is acquired. In this case, if an omnifocal image is generated using an image in which the subject is blurred, an unnatural omnifocal image in which the subject is blurred is obtained.

  An object of the present invention is to acquire an image in which a plurality of subjects are in focus and the influence of subject blurring is suppressed.

  In order to achieve the above object, an imaging apparatus according to an embodiment of the present invention is configured to generate a first image for focusing on a plurality of subjects by continuously imaging the subject with different focus lens positions. An imaging device that acquires the first image, the first evaluation value based on the second image acquired to set the lens position of the focus lens, and the first evaluation value acquired based on the first evaluation value. Evaluation value acquisition means for acquiring a second evaluation value based on one image, the first evaluation value based on the first image and the second image acquired at the same lens position, and the first A difference between the first evaluation value and the second evaluation value is determined by the determination unit that determines whether or not the difference between the first evaluation value and the second evaluation value is greater than the first value. If it is determined that the value is larger than the value of the second Control is performed so that the pixel area corresponding to the most focused subject in the second image for which the evaluation value has been acquired is not used as a pixel area when generating an image focused on the plurality of subjects. And a first control means.

  According to the present invention, it is possible to acquire an image in which a plurality of subjects are in focus and the influence of subject blurring is suppressed.

1 is a block diagram illustrating a configuration of a digital camera 100 that is an embodiment of an imaging apparatus embodying the present invention. It is a figure which illustrates omnifocal image acquired with the digital camera 100 which is embodiment of the imaging device which implemented this invention, and various conditions at the time of producing | generating the said omnifocal image. It is a flowchart explaining the focus bracket process of the digital camera 100 which is embodiment of the imaging device which implemented this invention. In the digital camera 100, which is an embodiment of an imaging apparatus that implements the present invention, an omnifocal image acquired when the subject moves during focus bracket shooting, and various types of images when generating the omnifocal image. It is a figure explaining conditions exemplarily. It is a flowchart explaining the synthetic | combination process of the digital camera 100 which is embodiment of the imaging device which implemented this invention. It is a flowchart explaining the compensation image setting process of the digital camera 100 which is embodiment of the imaging device which implemented this invention.

  A basic configuration of a digital camera (hereinafter simply referred to as a camera) 100 as an imaging apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram illustrating the configuration of a camera 100 that is an embodiment of an imaging apparatus embodying the present invention.

  The imaging lens group 101 is an imaging lens group including a zoom lens 102, a focus lens 103, an anti-vibration lens 104, and a diaphragm 105. The zoom lens 102 is an imaging lens that optically changes the angle of view by adjusting the focal length.

  The focus lens 103 is an imaging lens that adjusts the focal position. In the present embodiment, the focus position can be changed by operating the lens position of the focus lens 103 in the optical axis direction. Then, by continuously imaging the subject while changing the lens position of the focus lens 103, it is possible to acquire a plurality of images in a state where each is focused on a different position. Details of this will be described later.

  The anti-vibration lens 104 is an imaging lens that corrects image blur caused by various factors such as camera shake. The diaphragm 105 is a light amount adjustment member that adjusts the amount of light incident on the image sensor 106 described later. In this embodiment, the diaphragm 105 is provided with a mechanical shutter (not shown), and the time (exposure time) for exposing the image sensor 106 to light can be controlled by controlling the driving of the shutter. it can. In the case where a plurality of imaging lenses are not provided, a configuration in which functions such as zooming, focusing, and image stabilization included in each imaging lens described above are realized by one imaging lens may be used.

  In the following description, a so-called lens-integrated camera 100 in which a camera body and a lens barrel including an imaging lens group 101 are integrally provided will be described. Note that a so-called interchangeable lens type camera 100 in which the camera body and the lens barrel are separately provided may be adopted.

  The image sensor 106 is a charge storage type image sensor composed of a solid-state image sensor such as a CCD or a CMOS that can generate an image by accumulating charges, and pixels for imaging are two-dimensionally arranged. It is an imaging means. When an optical image of the subject that has passed through the imaging lens group 101 is formed on the image sensor 106, an analog electrical signal (analog image data) corresponding to the optical image of the subject is output. Note that an AFE (Analog Front End) (not shown) is connected to the image sensor 106, and it is possible to adjust an analog gain amount with respect to the acquired analog image data, and to correct aberration of the lens and perform sampling. The analog image data output from the AFE is converted into a digital electric signal (digital image data) by an A / D conversion unit (not shown) and output to the image processing unit 107. In the following description, digital image data is referred to as “image” unless otherwise specified.

  The image processing unit 107 is an image processing unit that performs image processing such as pixel interpolation processing and color conversion processing on the acquired image. The image processing unit 107 is also a photometric calculation unit that calculates the luminance value (luminance information) of the subject based on the acquired image. A method for calculating the luminance value of the subject will be described later. Furthermore, the image processing unit 107 can adjust the digital gain amount of the acquired image. Digital image data subjected to various processes by the image processing unit 107 is recorded in the memory 108.

  The memory 108 is a storage means that can be electrically erased and stored, and is, for example, an EEPROM represented by a flash memory or the like. The memory 108 stores various data used in the present embodiment. For example, a program executed in the camera 100, operation constants, various exposure conditions, calculation formulas and threshold values used in processing in the camera 100, predetermined values, and the like are stored in the memory 108 in advance. Further, the memory 108 is also used as an image display memory (video memory), a work area of each part of the camera 100, and a recording buffer of the recording memory 111 described later.

  The program executed in the camera 100 is a program for instructing an operation similar to the flow shown in FIGS. 3, 5, and 6 described later. Further, the memory 108 has a recording area for image data constituted by a recording element such as a RAM (Random Access Memory). The RAM has a storage capacity capable of recording a predetermined number of still images, a moving image for a predetermined time, and audio data, and can record acquired images.

  The display unit 109 is a display unit constituted by a TFT type LCD (Thin Film Transistor Driven Liquid Crystal Display) or the like. An image read from the memory 108 by a system control unit (hereinafter simply referred to as a CPU) 119 described later is converted into analog image data (hereinafter referred to as a display image) for display by a D / A conversion unit (not shown). And displayed on the display unit 109.

  Note that so-called live view display can be performed by sequentially displaying the display image on the display unit 109. Moreover, the structure which performs the said live view display with an electronic view finder (not shown) may be sufficient.

  The compression / decompression processing unit 110 is a processing unit that compresses / decompresses an image recorded in the memory 108 according to an image format. The recording memory 111 is a non-volatile recording medium such as a memory card or a hard disk capable of recording image data compressed and expanded by the compression / decompression processing unit 110. In the present embodiment, a recording memory 111 that can be inserted into and removed from the camera 100 is used. However, an optical disk such as a DVD-RW disk or a magnetic disk such as a hard disk may be used. . Further, the recording memory 111 may be built in the camera 100 in advance.

  The aperture driving unit 112 is a driving unit that drives the aperture 105 and a shutter (not shown) based on the set aperture value and exposure time. The aperture value and the exposure time are set (calculated) by the CPU 119 described later based on the luminance value of the subject calculated by the image processing unit 107. That is, automatic exposure (AE) control in the present embodiment is performed by driving the diaphragm 105 and the shutter by the diaphragm driving unit 112 in accordance with an instruction from the CPU 119. Note that the AE control of the present embodiment includes adjusting the gain amount in the image processing unit 107.

  The anti-vibration lens driving unit 113 is a drive control unit that calculates the amount of shake applied to the camera 100 based on information from the angular velocity sensor 125 and the gyro sensor 126 and drives the anti-vibration lens 104 so as to cancel the shake. The calculation of the amount of shake applied to the camera 100 may be calculated by the CPU 119. The zoom lens driving unit 115 is a driving unit that drives the zoom lens 102 in accordance with a zoom operation instruction from the user.

  The focus lens driving unit 114 is a lens driving unit that drives the focus lens 103. The lens position of the focus lens 103 can be moved by driving the focus lens driving unit 114 in accordance with an instruction from the CPU 119 described later.

  In the present embodiment, the focus lens driving unit 114 is driven based on an evaluation value (contrast evaluation value) for focus detection acquired by an evaluation value acquisition unit 120 described later, and the lens position of the focus lens 103 is moved. By this operation, the lens position of the focus lens 103 can be set to a state in which a predetermined subject is focused. This operation is referred to as AF (Auto Focus) control. Instead of the so-called contrast detection AF control described above, a so-called phase difference detection AF control may be performed.

  The operation unit 116 is an operation unit for inputting various instructions and settings by the user. The operation unit 116 includes a group of input devices such as switches, buttons, and dials. The operation unit 116 includes a release switch 117 and a menu operation button 118.

  When the release switch 117 is set to the SW1 state (for example, half-pressed state) by a user operation, a preparatory operation (imaging preparation) before imaging the subject is instructed. Note that imaging preparation refers to photometric calculation, AF control, and exposure control (including AE control).

  In addition, when the release switch 117 is set to the SW2 state (for example, fully pressed) by a user operation, an instruction to start imaging of the subject (main imaging) is instructed. Note that the imaging start of the subject refers to the start of exposure in the image sensor 106.

  Further, the user can set a shooting mode for shooting a subject by operating a menu operation button (mode selection means) 118. The settable shooting modes include at least a mode for performing focus bracket shooting.

  Further, the user can set the number of times of imaging (hereinafter referred to as the number of imaging) in one focus bracket process (described later) by operating the menu operation button 118.

  A system control unit (CPU) 119 is a control unit that comprehensively controls the overall operation of the camera 100. The CPU 119 can control the entire camera 100 by instructing each unit of the camera 100 to perform an operation in accordance with a user operation instruction. Note that the CPU 119 can execute a program stored in the memory 108 and control the operation and processing of the camera 100 according to the processing of the program. For example, a program for performing control of the image sensor 106, exposure control, AF control, zoom control, and the like is executed. Further, the CPU 119 is provided with an evaluation value acquisition unit 120, a distance calculation unit 121, a synthesis determination unit 122, a focus bracket control unit 123, and a synthesis unit 124. The details will be described below.

  The evaluation value acquisition unit 120 is an evaluation value acquisition unit for acquiring an evaluation value for focus detection (hereinafter referred to as a contrast evaluation value) based on the acquired contrast information of the image. In the present embodiment, the evaluation value acquisition unit 120 acquires information on the transition of the contrast evaluation value in one screen based on an image (second image) acquired at a predetermined interval while driving the focus lens 103. Hereinafter, an operation for acquiring information related to the transition of the contrast evaluation value will be referred to as a focus scan, and the details will be described.

  Note that the transition of the contrast evaluation value described above is represented by, for example, a graph as illustrated in the lower part of FIG. In this graph, the contrast evaluation value is the largest at the position where the subject is in focus. Therefore, by performing imaging at the lens position of the focus lens 103 where the contrast evaluation value is the largest, it is possible to acquire a composite image (first image) in a state where the subject is in focus. In the present embodiment, the above-described synthesis image is referred to as a synthesized image (first image). In addition, the lens position of the focus lens 103 that performs imaging for acquiring a composite image will be described as a focus position.

  In the present embodiment, the contrast evaluation value is calculated based on the contrast information of the acquired image. However, the present invention is not limited to this. For example, the contrast evaluation value may be calculated without acquiring (developing) the signal output from the image sensor 106 as an image.

  Based on the contrast evaluation value acquired by the evaluation value acquisition unit 120, the distance calculation unit 121 is information regarding the distance to the subject (hereinafter referred to as the subject distance) to be a target to be focused (focus target) in focus bracket shooting. Is a calculating means for calculating. In addition, the structure which calculates the information regarding a to-be-photographed object distance using the information regarding detection results, such as a face detection and a human body detection, may be sufficient.

  The distance calculation unit 121 is also a means for setting a region for focus bracket shooting (hereinafter referred to as a subject region) based on information about the calculated subject distance. In the present embodiment, focus bracket shooting is performed using a region from a position where a subject close to the camera 100 is present to a position where a subject at infinity is present among a plurality of subjects detected as in-focus objects as a subject area. To do. Then, by performing focus bracket shooting based on the subject area, it is possible to acquire a plurality of composite images having different in-focus positions.

  In the present embodiment, information on the distance from the image sensor 106 to the subject is the subject distance, but the present invention is not limited to this. For example, the configuration may be such that information on the distance from the imaging lens group 101 to the subject is the subject distance. Further, the subject distance may be calculated by a known method other than the above-described method such as a phase difference method using a distance measuring sensor.

  Whether the combination determination unit 122 is an image suitable for generating image data (hereinafter referred to as an omnifocal image) in a state where the combined image is focused on a plurality of subjects based on the acquired contrast evaluation value. It is a determination means for determining whether or not. The combination determination unit 122 is also a control unit (first control unit) that sets an image to be used when generating an omnifocal image from among the combined images based on the determination result. In the present embodiment, a pixel region in which a combined image determined to be an image that is not suitable for generating an omnifocal image by the synthesis determination unit 122 is a predetermined area when generating an omnifocal image. The pixel area is controlled so as not to be used. Details of this will be described later.

  Further, the composition determination unit 122 sets a compensation image for compensating the pixel region corresponding to the most focused subject in the composite image determined not to be an image suitable for generating an omnifocal image. It is also a compensation image setting means. Details of this will be described later.

  The focus bracket control unit 123 is a control unit that sets shooting conditions for performing focus bracket shooting based on information such as the acquired contrast evaluation value and subject distance. The imaging conditions in the present embodiment are the exposure amount, the number of times of imaging, and the focus position described above when performing focus bracket shooting.

  Note that the exposure amount in this embodiment is a value that changes based on exposure conditions such as the aperture value, shutter speed, and gain amount. Accordingly, the focus bracket control unit 123 is also an exposure control unit that sets the exposure amount when performing the focus bracket photographing by controlling the operations of the focus lens 103, the aperture 105, and the shutter.

  The synthesizing unit 124 is a synthesizing unit that reads a plurality of synthesized images acquired by the focus bracket process from the memory 108 and synthesizes the plurality of synthesized images to generate an omnifocal image. Specifically, the synthesizing unit 124 extracts a predetermined pixel area from each of the acquired plurality of synthesized images based on the determination result of the synthesizing determination unit 122, and generates an omnifocal image by synthesizing. Here, the pixel area to be extracted differs for each synthesized image. Details of this will be described later. A series of processes from the calculation of the subject distance to the acquisition of the omnifocal image described above will be described as a focus bracket process in the present embodiment. The focus bracket process will be described later. The basic configuration of the camera 100 has been described above.

  Details of the focus bracket process will be described below with reference to FIGS. FIG. 2 is a diagram illustratively illustrating an omnifocal image acquired by the camera 100 that is an embodiment of an imaging apparatus that implements the present invention, and various conditions for generating the omnifocal image. FIG. 2A is a diagram for exemplarily explaining the entire burnt edge image to be acquired and the subject included in the angle of view of the omnifocal image. In the present embodiment, a case in which a person 1, a person 2, and a tree are present within the angle of view will be described as an example. FIG. 2B is a diagram for exemplarily explaining the relationship between the subject distance of the subject existing within the angle of view and the contrast evaluation value, in which the upper part is the subject distance and the lower part is the contrast evaluation value. Is shown. As shown in FIG. 2B, the subject distances for the respective subjects are about 1 m (L1) for the person 1, about 5 m for the person 2, and about 30 m (L3) for the tree. That is, in this embodiment, the subject closest to the camera 100 is the person 1 and the subject farthest from the camera 100 is a tree. Note that even if the aperture value is the same, the depth of field changes according to the subject distance, so the horizontal axis in FIG. 2B indicates the subject distance converted to logarithm.

  Hereinafter, the focus bracketing process in the case of imaging at the angle of view shown in FIG. 2 will be exemplarily described with reference to FIG. FIG. 3 is a flowchart for explaining the focus bracketing process of the camera 100 which is an embodiment of the imaging apparatus embodying the present invention. In the present embodiment, a case will be described in which a mode for performing focus bracket shooting is set in advance by the user operating the menu operation button 118. In addition, information and image data acquired in each step described below are appropriately recorded in the memory 108 and read out from the memory 108.

  The focus bracket process is started in response to the release switch 117 being set to the SW1 state (half-pressed) by the user. In step S101, the CPU 119 performs imaging while changing the lens position of the focus lens 103 at a predetermined interval. Then, the CPU 119 acquires a plurality of focus detection images (second images) by the imaging. Information on the predetermined interval described above is recorded in the memory 108 in advance. Further, the predetermined interval for changing the lens position of the focus lens 103 may be any as long as it can acquire information on the transition of the contrast evaluation value within the angle of view.

  The focus detection image (second image) described above is an image acquired to set a focus position in the focus bracket process. Details of this will be described later.

  In step S101, the image processing unit (photometric calculation means) 107 performs photometric calculation based on the acquired focus detection image, and calculates the luminance value (luminance information) of the subject. Specifically, in this embodiment, one screen of the acquired focus detection image is divided into a plurality of blocks, and an average luminance value is calculated for each of these blocks. Then, a representative luminance value calculated by integrating the average luminance values of all blocks is calculated. Furthermore, the luminance value of the subject used for various processes to be described later is calculated by averaging the representative luminance values calculated for each focus detection image.

  Note that the photometric calculation method is not limited to this, and the luminance value may be calculated by another known method. For example, in the present embodiment, the luminance value of the subject is calculated by averaging the representative luminance values calculated for each focus detection image, but the present invention is not limited to this. A configuration may be adopted in which a predetermined focus detection image as a representative is set and the representative luminance value of the focus detection image is set as the luminance value of the subject.

  Next, in step S102, the evaluation value acquisition unit 120 performs the above-described focus scan based on the acquired plurality of focus detection images (second images), and relates to the transition of the contrast evaluation value within the angle of view. Get information. Then, the evaluation value acquisition unit 120 acquires the largest (becomes a peak value) contrast evaluation value for each region exceeding a predetermined threshold value in the transition of the contrast evaluation value acquired by the focus scan. Note that any value may be set as the above-described threshold. In the present embodiment, the contrast evaluation value serving as the peak value of each region is set as the first contrast evaluation value (first evaluation value) α (n) of the subject to be focused in the focus bracket process ( n is a natural number). Then, the lens position of the focus lens 103 that has acquired the first evaluation value is set as the focus position. A method for setting the focus position will be described later.

  The first evaluation value α (n) is assigned a number in order from the closest side of the camera 100 to the infinity side, and imaging is performed along the number. For example, as illustrated in FIG. 2B, a person 1, a person 2, and a tree whose contrast evaluation values are larger than a threshold are subjects to be focused. Accordingly, the first evaluation values α (1), α (2), and α (3) are set in order from the closest side of the camera 100 to the subject to be focused. Then, the subject is imaged in the order of person 1, person 2, and tree.

  Next, in step S103, the distance calculation unit 121 calculates information related to the subject distance for each subject based on the information related to the first evaluation value α (n) acquired in advance. In the present embodiment, the subject distance of the person 1 is L1, the subject distance of the person 2 is L2, and the subject distance of the tree is L3.

  In step S103, the distance calculation unit 121 sets an area (subject area) for focus bracket shooting. In the present embodiment, as illustrated in FIG. 2B, an area from the person 1 to the tree (L3-L1 area) is set as the subject area.

  Next, in step S104, the focus bracket control unit 123 sets an imaging condition at the time of focus bracket shooting based on the previously calculated information on the luminance value and the subject distance of the subject. Specifically, the focus bracket control unit 123 sets an exposure amount (aperture value, shutter speed, gain amount) that can acquire an image that is in appropriate brightness and focused on the subject. . In the present embodiment, the same aperture value is set in one focus bracket process. Here, even if the aperture value is the same, the depth of field varies depending on the subject distance, so it is necessary to set an aperture value that can be focused on a plurality of subjects to be imaged. Furthermore, when the aperture value is large (the aperture diameter is small), the resolution of the image is lowered due to the light diffraction phenomenon, so it is necessary to set an aperture that does not reduce the resolution as much as possible.

  Further, the focus bracket control unit 123 sets the number of times of imaging and the focus position in one focus bracket process based on the set aperture value and information on the subject distance. The number of times of imaging and the focus position set here are set so as to cover the entire subject area set previously. That is, the focus position and the number of imaging are set so that the subject to be focused is included within at least one depth of field of the plurality of images to be acquired. The exposure amount, the number of imaging operations, and the focus position described above are the imaging conditions of this embodiment. Note that the aperture value, the number of times of imaging, and the focus position in the focus bracket process may be set in any way as long as an omnifocal image focused on the entire subject area can be generated. In the following description, the focus bracketing process is performed when the number of times of imaging is set to 3 and the focus position is set so that the entire region of the subject area can be covered (focused) by 3 times of imaging. Will be exemplarily described.

  Next, in step S <b> 105, the CPU 119 drives the diaphragm 105 via the diaphragm driver 112 based on the information regarding the previously calculated diaphragm value.

  Next, in step S106, the CPU 119 determines whether or not the release switch 117 is in the SW2 state. The process of step S106 is repeated until the release switch 117 is changed to the SW2 state.

  Next, in step S107, the focus bracket control unit 123 performs imaging based on the previously set information regarding the imaging conditions, and acquires a composite image (n) used when generating an omnifocal image (n is a natural number). ). Note that, as described above, in the present embodiment, a composite image (second image) is acquired in order from the closest side of the camera 100 toward the infinity side based on the set imaging condition.

  In this embodiment, every time a synthesized image is acquired, the processes in steps S107 to S112 are repeated. For example, when the number of times of imaging is set to 3, the combined images (1) to (3) are sequentially acquired by repeating the processing of steps S107 to S112 three times. In addition, according to the set imaging frequency, the structure which acquires all the synthesized images previously may be sufficient. In this case, after all the synthesized images are acquired, the processes of steps S108 to S111 described later are executed.

  Next, in step S108, the evaluation value acquisition unit 120 acquires a contrast evaluation value (second evaluation value) β (n) based on the acquired contrast information of the combined image (n) (n is a natural number). .

  In the present embodiment, as shown in FIG. 4A, the second evaluation value β at the same lens position of the focus lens 103 as the first evaluation value α (n) with respect to the optical axis direction of the camera 100. (N) is acquired. This is because the synthesized image (n) is obtained at the lens position of the focus lens 103 from which the first evaluation value α (n) has been obtained.

  Note that FIG. 4 shows an omnifocal image acquired when the subject moves during focus bracket shooting, and the omnifocal image generated in the camera 100 which is an embodiment of the imaging apparatus embodying the present invention. It is a figure explaining various conditions at the time of doing. FIG. 4A is a diagram illustrating an example of the relationship between the subject distance and the contrast evaluation value in a state where the person 2 is shaken by the person 2 moving from the initial position at which imaging starts. The value β (n) is indicated by a point, and the first evaluation value α (n) is indicated by a broken line. FIG. 4B is a diagram exemplarily illustrating an omnifocal image generated by combining a plurality of combined images acquired under the conditions illustrated in FIG.

  In the present embodiment, the second evaluation value β (n) is acquired based only on the contrast information of the composite image (n) acquired previously. That is, the second evaluation value β (n) is acquired without performing a focus scan. Therefore, as illustrated in FIG. 4A, the second evaluation value β (n) is acquired as a contrast evaluation value for each set focus position.

  Here, the magnitude of the second evaluation value β (n) varies depending on the focus state of the subject in the synthesized image (n) from which the second evaluation value β (n) has been acquired. For example, the second evaluation value increases as the subject is focused more clearly in the combined image.

  In this embodiment, the same lens position as that of the focus lens 103 capable of acquiring the first evaluation value α (n) is set as the focus position. Therefore, the first evaluation value and the second evaluation value can be acquired at the same lens position. On the other hand, in the case of a configuration in which a position different from the lens position of the focus lens 103 capable of acquiring the first evaluation value α (n) is set as the focus position, the first evaluation value and the second evaluation value are Are acquired at different lens positions. That is, the relationship between the lens position of the focus lens 103 that can acquire the first evaluation value α (n) and the lens position of the focus lens 103 that can acquire the second evaluation value β (n) depends on the focus position to be set. Change.

  As described above, the second evaluation value β (n) is based on the contrast information of the composite image acquired based on at least the first evaluation value α (n) regardless of the lens position of the focus lens 103. Is the value obtained.

  Note that numbers are assigned to the acquired second evaluation values in order from the closest side of the camera 100 to the infinity side in the same manner as the first evaluation value described above. For example, in the present embodiment, person 1, person 2, and tree are set as the subjects to be focused on, so the second evaluation values corresponding to these subjects are β (1) and β (2), respectively. , Β (3).

  Next, in step S109, the combination determination unit 122 compares the first evaluation value α (n) acquired previously with the second evaluation value β (n), and acquires the combined image (n) acquired. Is suitable for generating an omnifocal image. The details will be described below.

  When focus bracket shooting is performed, a plurality of images with different in-focus states are acquired by continuously imaging a subject by changing the lens position of the focus lens 103. Therefore, the period from when the user gives an imaging instruction to when the actual imaging is performed changes according to the imaging order of the subject to be focused. In particular, for a subject whose order of imaging is slow, the period from when the user gives an imaging instruction until when the imaging is actually performed becomes long.

  Here, in the present embodiment, a plurality of synthesized images are acquired so that different synthesized subjects are focused on each synthesized image. And in this embodiment, it is the structure which produces | generates one omnifocal image by extracting the pixel area | region which has focused in each to-be-combined image, and synthesize | combining each pixel area | region. In other words, the synthesized image of the present embodiment has a different subject in focus for each image.

  Therefore, when a subject to be focused is blurred in a certain synthesized image, an omnifocal image generated using the synthesized image is an image in which the subject to be focused is blurred. End up. In the present embodiment, an image in which the subject is blurred and an unclear image in which the subject is deformed into an irregular shape are collectively referred to as an image in which the subject is blurred.

  For example, as illustrated in FIG. 4A, the person 2 is moved during the focus bracket shooting, so that the person 2 is blurred in the composite image (2) acquired to focus on the person 2. The image may become unclear. Therefore, even if an omnifocal image is generated using the pixel region in focus in the combined image (2), as shown in FIG. 4B, an unnatural image in which the person 2 is blurred turn into.

  Therefore, in the present embodiment, it is determined whether or not the difference between the first evaluation value α (n) and the second evaluation value β (n) is larger than a predetermined threshold value (first value). Then, it is determined whether or not the pixel region in which the combined image (n) is in focus is suitable for generating an omnifocal image. Then, in accordance with the result of the determination, a composite image and a pixel area used for composition when generating an omnifocal image are set.

  Returning to FIG. 3, in step S <b> 109, the composition determination unit 122 calculates a value (hereinafter referred to as a movement ratio) calculated by dividing the second evaluation value β (n) by the first evaluation value α (n). It is determined whether or not it is larger than a predetermined ratio (first value) γ. The movement ratio is a value indicating the difference between the position of the subject when the imaging is instructed and the position of the actually captured subject. The predetermined ratio γ described above is a value stored in the memory 108 in advance. The predetermined ratio γ may be any value as long as it can be determined whether or not the synthesized image is an image suitable for generating an omnifocal image.

  Here, the comparison between the first evaluation value α (n) and the second evaluation value β (n) is performed using contrast evaluation values calculated based on the same subject. For example, the second evaluation value β (1) acquired based on the synthesized image (1) is used for comparison with the first evaluation value α (1) regarding the person 1. Further, the second evaluation value β (3) acquired based on the synthesized image (3) is used for the comparison with the first evaluation value α (3) regarding the tree.

  In addition, it is not the method of calculating | requiring the movement ratio mentioned above, but whether the difference of 1st evaluation value (alpha) (n) and 2nd evaluation value (beta) (n) is larger than predetermined value (2nd value). It is also possible to adopt a configuration that determines the above.

  Next, when it is determined that the calculated movement ratio is not greater than the predetermined ratio γ (NO in step S109) (β (n) / α (n) ≦ γ), in step S110, the combination determination unit (first Control unit) 123 sets the composite flag (n) of the composite image (n) to be valid. That is, the composition determination unit 122 determines that the subject to be focused is not blurred in the composite image (n). Then, the combination determination unit 122 sets the combined image (n) as an image used when generating an omnifocal image.

  Furthermore, the composition determination unit 122 sets the pixel area focused in (n) of the composition image set for composition as the pixel area used for composition when generating the omnifocal image. For example, when the synthesis flag (1) of the synthesized image (1) is set to be valid, the pixel region that is most focused on the synthesized image (1) is used for synthesis when generating the omnifocal image. Set to pixel area.

  Next, when it is determined that the movement ratio is larger than the above-described predetermined ratio γ (β (n) / α (n)> γ) (YES in step S109), the composition determination unit 122 acquires in step S111. The composite flag (n) of the composite image (n) thus set is set to invalid.

  Next, in step S112, the focus bracket control unit 123 determines whether or not the number of times that imaging has already been completed has reached the set number of imaging. If it is determined in step S112 that the number of times of imaging has not reached the set number of times of imaging, the process returns to step S107, and the processes of steps S107 to S112 described above are repeated. For example, when the set number of times of imaging is 3 and imaging for acquiring the synthesized image (1) and the synthesized image (2) has been completed so far, the synthesized image (3) is obtained. In order to do so, the processes of steps S107 to S112 described above are repeated.

  If it is determined that the number of times of imaging has reached the set number of times of imaging (YES in step S112), the synthesis determination unit 122 performs a synthesis process in step S113. Details of the synthesis process will be described later. When the compositing process ends, the focus bracket process ends. The above is the focus bracket process of the present embodiment.

  Hereinafter, the composition processing of this embodiment will be described with reference to FIG. FIG. 5 is a flowchart for describing the composition processing of the camera 100 which is an embodiment of the imaging apparatus embodying the present invention. In step S201, the composition determination unit 122 determines whether the composition flag of the composite image (1) is set to be valid. Here, as described above, the composite image (1) is an image acquired to focus on the subject closest to the camera 100 (for example, the person 1 in FIG. 2B).

  If it is determined that the combination flag of the image to be combined (1) is set valid (YES in step S201), the process proceeds to step S204. On the other hand, if it is determined that the composite flag of the composite image (1) is set to invalid (NO in step S201), the process proceeds to step S202.

  Next, in step S202, the composition determination unit (second control unit) 123 performs control for causing the display unit 109 to display a warning display indicating that the focus bracket process is to be stopped. Next, in step S203, the composition determination unit 122 determines whether to stop the focus bracket process. The warning display is a display for asking the user whether or not to cancel the focus bracket process.

  The composite image (1) is an image that is first acquired from an imaging instruction by the user in one focus bracket process. That is, the synthesized image (1) is an image acquired by the first imaging after the imaging instruction by the user.

  As described above, the synthesized image (1) is an image acquired in the shortest time from the user's imaging instruction as compared with other synthesized images. Therefore, the synthesized image (1) is an image in which the subject is less likely to be shaken compared to other synthesized images.

  When the subject is blurred in the synthesized image (1) (the synthesis flag is set to invalid), the subject is also blurred in the synthesized image acquired after the synthesized image (1). There is a high probability of being.

  Therefore, in the present embodiment, a warning is displayed on the display unit 109 when the composite flag of the composite image (1) is set to invalid. Then, based on the user's operation on the warning display, it is determined whether or not to stop the current focus bracket process. With this configuration, it is possible to suppress unnecessary use of the focus bracket process in order to generate an omnifocal image with a high probability that the subject intended by the user is blurred.

  When canceling the focus bracket process, the current composition process is terminated and the next focus bracket process is started. If the focus bracket process is not canceled, the process proceeds to step S204.

  Next, in step S204, the focus bracket control unit 123 sets the count number of processes completed so far to 1 (Count = 1). In step S205, the focus bracket control unit 123 sets the value of the variable n to n = Count + 1 (n is a natural number). For example, in the process immediately after the process of step S204 is completed, the count is set to 1 (Count = 1), so n is set to 2 (n = 2).

  Next, in step S206, the composition determination unit 122 determines whether the composition flag of the composite image (n) is set to be valid. If it is determined that the composite flag of the composite image (n) is set to be valid (YES in step S206), the process proceeds to step S208. On the other hand, if it is determined that the composite flag of the composite image (n) is set to invalid (NO in step S206), the process proceeds to step S207.

  Next, in step S207, the synthesis determination unit (compensation image setting unit) 123 sets a compensation image for extracting a pixel region used for synthesis, instead of the synthesized image (n) in which the synthesis flag is set to invalid. Hereinafter, the details of the compensation image setting process for setting the compensation image described above will be described with reference to FIG. FIG. 6 is a flowchart for explaining a compensation image setting process of the camera 100 which is an embodiment of the imaging apparatus embodying the present invention.

  In the present embodiment, a pixel area in a focused state is extracted for each of a plurality of acquired combined images, and an omnifocal image is generated by combining the extracted pixel areas. In this case, the pixel area to be extracted is different for each composite image. Then, one omnifocal image is generated by combining different pixel regions.

  In the present embodiment, when the composite flag (n) of the composite image (n) is set to be invalid, the pixel region corresponding to the subject in focus in the composite image (n) is the omnifocal. It is not used as a pixel area when generating an image. For example, it is assumed that the synthesis flag (2) of the synthesized image (2) is set to invalid. In this case, the pixel area (2) corresponding to the person 2 who is the most focused subject in the synthesized image (2) (for example, the area surrounded by the dotted line shown in FIG. 4B) It is not used as a pixel area when generating a focus image.

  Therefore, it is necessary to set a pixel region that compensates for the pixel region (2) as a pixel region used when generating an omnifocal image. Therefore, when the composite flag (n) of the composite image (n) is set to invalid, it is necessary to generate an omnifocal image using the pixel area of the composite image other than the composite image (n). is there.

  Therefore, in this embodiment, when the composite flag of the composite image (n) is set to invalid, the composite image other than the composite image (n) is used as a compensation image used when generating the omnifocal image. Set. And among the pixel areas of the compensation image, the same pixel area as the focused pixel area in the synthesized image (n) is used for generating the omnifocal image. That is, instead of the pixel region that was scheduled to be extracted from the synthesized image (n) when the omnifocal image is generated, a compensation image that extracts a pixel region at the same position as the pixel region is set.

  In the present embodiment, a synthesized image corresponding to a focus position within a predetermined threshold (third value) is set as a corrected image with reference to the focus position of the synthesized image in which the synthesis flag is set to invalid. The details will be described below.

  When the compensation image setting process is started, the focus bracket control unit 123 sets a predetermined threshold (third value) for selecting a compensation image in step S301. As described above, the predetermined threshold value is a threshold value based on the focus position of the synthesized image (n) in which the synthesis flag (n) is set to invalid. Since the predetermined threshold value is a value related to the focus position, it changes according to the aperture value set during focus bracket shooting.

  For example, when the aperture value at the time of focus bracket shooting is the aperture value F5.6 (first aperture value), the above-described predetermined threshold is set more than when the aperture value is F11 (second aperture value). Enlarge. This is because the depth of field at the time of imaging becomes deeper as the aperture value is larger (the aperture diameter is smaller).

  As described above, a composite image whose corresponding focus position is within the above-described threshold is set as a compensation image. With this configuration, it is possible to set a composite image with a small subject blur in the pixel region to be compensated as a compensation image. That is, a composite image with a small subject blur can be set as a compensation image.

  Next, in step S302, the focus bracket control unit 123 determines whether or not the focus position of the combined image (1) is within a predetermined threshold. In one focus bracket process, the shorter the period from the user's instruction to start imaging until the actual imaging starts, the lower the probability that the subject will blur in the combined image. In particular, in one focus bracket process, the composite image (1) acquired by the first imaging has a lower probability of subject blurring than other composite images.

  Therefore, in the process of step S302, it is determined whether or not the focus position when the composite image (1) is captured is within a predetermined threshold value set previously.

  If it is determined in step S302 that the focus position when the composite image (1) is captured is within a predetermined threshold, the focus bracket control unit 123 in step S303 captures the composite image (1). It is set as a compensation image for the composite image (n). With this configuration, it is possible to set a composite image in which the subject is difficult to shake as a compensation image.

  Next, in step S304, the focus bracket control unit 123 determines whether or not an image corresponding to the synthesized image (n−1) other than the synthesized image (1) is obtained among the obtained synthesized images. To do. That is, it is determined whether or not a composite image other than the composite image (1) has been acquired before the composite image (n) is acquired.

  If it is determined in step S304 that the combined image (n−1) is acquired (in addition to the combined image (1)), the process proceeds to step S305. If it is determined in step S304 that the combined image (n-1) has not been acquired (other than the combined image (1)), the process proceeds to step S303.

  Next, in step S305, the focus bracket control unit 123 determines a synthesized image whose focus position is within a predetermined threshold in the obtained synthesized images (1) to (n-1). If it is determined in the process of step S305 that there is a composite image having a focus position within a predetermined threshold among the composite images (1) to (n-1), the process proceeds to step S306. If it is determined in step S305 that there is no synthesized image having a focus position within a predetermined threshold among the synthesized images (1) to (n-1), the process proceeds to step S303. .

  Next, in step S306, the focus bracket control unit 123, among the acquired composite images (n−1), the corresponding focus position is within a predetermined threshold and the image that is captured (acquired) is the earliest. To the compensation image. For example, when the composite flag (3) of the composite image (3) is set to invalid and only the focus position of the composite image (2) is within a predetermined threshold, the composite image ( 2) is set as a compensation image. When the setting of the compensation image is completed in the process of step S303 or step S306, the compensation image setting process is terminated.

  Here, when it is determined NO in the process of step S304 or the process of step S305, there is no composite image acquired by capturing an image at a focus position within a predetermined threshold. In this case, the synthesized image (1) is set as the compensation image. By setting the combined image (1) as the compensation image, it is possible to set the combined image with as little subject blur as possible as the compensation image. That is, in the present embodiment, at least a composite image acquired by imaging before the composite image (n) in which the composite flag (n) is set to be invalid is set as a compensation image.

  Note that the compensation image setting method of the present embodiment is not limited to the above-described method. For example, the composition image (1) may always be set as the compensation image. Further, one of the synthesized images (the synthesized image (n−1) or the synthesized image (n + 1)) acquired before and after the synthesized image (n) in which the synthesis flag is set to be invalid is used as a compensation image. The configuration may be set.

  Returning to FIG. 5, in step S208, the focus bracket control unit 123 adds 1 to the count set in step S205 (Count = Count + 1). In step S209, the focus bracket control unit 123 determines whether or not the number of counts up to now has reached the set number of times of imaging.

  If it is determined that the count has not reached the number of times of imaging (NO in step S209), the process returns to step S205, and the processes in steps S205 to S209 are repeated for the remaining composite images.

  If it is determined that the count number has reached the number of times of imaging (YES in step S209), in step S210, the combining unit 124 combines pixels from the combined image and the compensation image in which the combining flag is set to be valid. Extract regions. Then, the combining unit 124 combines the extracted image areas to generate an omnifocal image. Finally, the generated omnifocal image is recorded in the memory 108, and the image composition process ends. The generated omnifocal image may be displayed on the display unit 109 for review. The above is the image composition processing of the present embodiment.

  As described above, in the present embodiment, the focus is determined by determining whether or not the difference between the first evaluation value α (n) and the second evaluation value β (n) is larger than a predetermined threshold value. It is determined whether or not the image acquired by bracket shooting is an image suitable for generating an omnifocal image. Then, a composite image for synthesis for generating an omnifocal image is set according to the result of the determination.

  With this configuration, even when an image in which the subject is shaken by focus bracket shooting is acquired, an omnifocal image in which the shake of the subject is suppressed can be generated. Therefore, the camera 100 of the present embodiment can acquire an image in which a plurality of subjects are in focus and the influence of subject blurring is suppressed.

  In addition, when it is determined that the acquired composite image is not an image suitable for generating an omnifocal image, compensation is performed to compensate the pixel region corresponding to the subject that is most focused on the composite image. Set the image. Then, the pixel area extracted from the compensation image is set as the pixel area when generating the omnifocal image. Here, the composite image set as the compensation image uses at least an image with a small subject blur. With the configuration described above, an omnifocal image in which blurring of the subject is suppressed can be generated even if an image in which the subject is blurred in focus bracket shooting is acquired.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to this embodiment, A various deformation | transformation and change are possible within the range of the summary. For example, when there are many images in which the combination flag is set to invalid among all the acquired images to be combined, it is difficult to acquire an image in a state in which the subject intended by the user is properly focused. Therefore, it may be configured to determine whether or not to generate an omnifocal image according to the proportion of images in which the combination flag is set to be effective among all the combined images acquired by focus bracket shooting. . For example, if more than half of the acquired images to be combined are set to invalid, the focus bracket processing currently being processed is canceled for the user, and the process proceeds to the next processing. Is displayed on the display unit 109.

  With this configuration, it is possible to shift to the next focus bracketing process without generating an omnifocal image with a low probability of focusing on the subject intended by the user. That is, it is possible to proceed to the next process without generating an omnifocal image with a small effect. Therefore, it is possible to suppress wasted time for generating an omnifocal image with a small effect.

  In the present embodiment, the focus bracket photographing is performed with the same aperture value in one focus bracket process, but the present invention is not limited to this. For example, as long as the aperture value covers the entire subject area, the configuration may be such that imaging is performed by changing the aperture value during one focus bracketing process. For example, in the first imaging, a composite image that is focused on a relatively wide area is acquired by setting an aperture value on the small aperture side and imaging. In other cases of imaging, the aperture value on the open side is set for imaging. With this configuration, when the subject is blurred in the synthesized image other than the synthesized image (1), the synthesized image (1) focused on a wide area is set as the compensation image. Can do. In this case, it is possible to acquire an omnifocal image in a state in which a wide area within the angle of view is focused while suppressing blurring of the subject.

  In addition, when the composite flag of the acquired composite image is set to invalid, the composite image is acquired by focusing on the subject focused on the composite image. May be. In this case, even if the subject is blurred in the acquired synthesized image, it is possible to newly acquire the synthesized image in a state where the subject is not blurred. Therefore, it is possible to generate an omnifocal image in which blurring of the subject is suppressed.

  Further, in the above-described embodiment, it is assumed that the subject is moved during focus bracket shooting, and thus a composite image in which the subject is blurred is acquired. However, the present invention is not limited to this. For example, even when an image in which the subject is shaken due to the influence of the shake applied to the camera 100 is acquired, an image in which the influence of the shake of the subject is suppressed by executing the focus bracketing process and the image combining process described above. Can be generated. Here, the amount of blur applied to the camera 100 is detected based on outputs from the angular velocity sensor 125 and the gyro sensor 126.

  Note that the user may operate the menu operation button 118 to select a mode for executing the focus bracketing process and the image composition process described above. That is, the configuration shown in FIGS. 3, 5, and 6 may be executed in accordance with the mode set by the user.

  In the above-described embodiment, the configuration is such that the control unit and the processing unit provided in the camera 100 operate in cooperation with each other to control the operation of the camera 100. However, the configuration is not limited thereto. It is not something. Even if the program according to the flow of FIG. 3, FIG. 5, or FIG. 6 is stored in the memory 108 in advance, and the CPU 119 executes the program, the operation of the camera 100 is controlled. Good.

  Moreover, as long as it has the function of a program, it does not ask | require the form of programs, such as an object code, the program run by an interpreter, and the script data supplied to OS. The recording medium for supplying the program may be, for example, a magnetic recording medium such as a hard disk or a magnetic tape, or an optical / magneto-optical recording medium.

(Other embodiments)
The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various recording media. Then, the computer (or CPU, MPU, etc.) of the system or apparatus reads out and executes the program.

100 Digital camera (imaging device)
103 Focus lens 119 System controller (CPU)
120 evaluation value acquisition unit (evaluation value acquisition means)
122 Synthesis determination unit (determination means, first control means)

Claims (15)

An imaging apparatus that acquires a first image for generating an image focused on a plurality of subjects by continuously imaging subjects with different lens positions of a focus lens,
A first evaluation value based on the second image acquired to set the lens position of the focus lens, and a second evaluation value based on the first image acquired based on the first evaluation value; Evaluation value acquisition means for acquiring
It is determined whether the difference between the first evaluation value and the second evaluation value based on the first image and the second image acquired at the same lens position is larger than the first value. A determination means;
When the determination means determines that the difference between the first evaluation value and the second evaluation value is greater than the first value, the second evaluation value acquired from the second evaluation value First control means for controlling so as not to use a pixel area corresponding to the most focused subject in the image as a pixel area when generating an image focused on the plurality of subjects. An imaging apparatus characterized by that.   The evaluation value acquisition means acquires the first evaluation value based on the contrast information of the second image, and acquires the second evaluation value based on the contrast information of the first image. The imaging apparatus according to claim 1, wherein the imaging apparatus is characterized.   When the determination unit determines that the difference between the first evaluation value and the second evaluation value is not larger than the first value, the first control unit performs the second evaluation. Controlling to use a pixel area corresponding to the most focused subject in the first image from which the value is acquired as a pixel area when generating an image focused on the plurality of subjects. The imaging apparatus according to claim 1, wherein the imaging apparatus is characterized.   The determination means determines whether or not a value obtained by dividing the second evaluation value acquired by the evaluation value acquisition means by the first evaluation value is larger than a predetermined ratio. The imaging device according to any one of 1 to 3.   The said determination means determines whether the difference of the said 1st evaluation value and the said 2nd evaluation value is larger than a 2nd value. The imaging device described in 1.   When the determination means determines that the difference between the first evaluation value and the second evaluation value is not greater than the first value, the first evaluation value acquired from the first evaluation value 6. The imaging apparatus according to claim 1, further comprising: a combining unit configured to generate an image focused on the plurality of subjects by combining pixel regions of the image.   The imaging apparatus according to claim 6, wherein the synthesizing unit uses a different pixel area for each of the first images for synthesis.   The first image obtained by acquiring the second evaluation value when the determination unit determines that the difference between the first evaluation value and the second evaluation value is larger than the first value. And a compensation image setting means for setting a compensation image for compensating a pixel region corresponding to the most focused subject in the first image different from the first image. Item 8. The imaging device according to any one of Items 1 to 7.   9. The compensation image setting unit according to claim 8, wherein, among the acquired first images, the image having the earliest image capturing order is set as the compensation image in one continuous image capturing. Imaging device.   The compensation image setting means is an image in which the lens position of the focus lens is within a predetermined range based on the lens position of the focus lens from which the second evaluation value is acquired, among the acquired first images. The imaging apparatus according to claim 8 or 9, wherein is set to the compensation image. A second control unit that performs control to display on the display unit a warning display to the effect that generation of an image focused on the plurality of subjects is stopped;
The second control means determines that the second evaluation value acquired based on the first acquired image among the acquired first images is different from the first evaluation value by the determination means. The imaging apparatus according to any one of claims 1 to 10, wherein when it is determined that the value is larger than the first value, the warning is displayed on the display unit. An imaging device that acquires a first image by continuously imaging a subject with different lens positions of a focus lens in order to generate an image focused on a plurality of subjects,
The first evaluation value acquired based on the second image acquired to set the lens position of the focus lens and the first acquired by imaging at the lens position of the focus lens based on the first evaluation value. Evaluation value acquisition means for acquiring a second evaluation value based on the image of
Determining means for determining whether or not a difference between the first evaluation value and the second evaluation value acquired based on the first evaluation value is larger than the first value;
When the determination means determines that the difference between the first evaluation value and the second evaluation value is larger than the first value, the most focused subject in the second image An image pickup apparatus comprising: a first control unit configured to control a pixel area so as not to be used as a pixel area when generating an image focused on the plurality of subjects. A method of controlling an imaging apparatus that acquires a composite image for generating an image focused on a plurality of subjects by continuously imaging subjects with different lens positions of a focus lens,
A first evaluation value based on the second image acquired to set the lens position of the focus lens, and a second evaluation value based on the first image acquired based on the first evaluation value; , Obtaining an evaluation value, and
It is determined whether the difference between the first evaluation value and the second evaluation value based on the first image and the second image acquired at the same lens position is larger than the first value. A determination process;
When it is determined by the determination step that the difference between the first evaluation value and the second evaluation value is larger than the first value, the second evaluation value is acquired. A first control step for controlling not to use a pixel region corresponding to a subject that is most in focus in the image as a pixel region when generating an image focused on the plurality of subjects. And a method of controlling the imaging apparatus. A method for controlling an imaging apparatus that acquires a first image by continuously imaging a subject with different lens positions of a focus lens in order to generate an image focused on a plurality of subjects,
The first evaluation value acquired based on the second image acquired to set the lens position of the focus lens and the first acquired by imaging at the lens position of the focus lens based on the first evaluation value. A second evaluation value based on the image of the evaluation value acquisition step of acquiring,
A determination step of determining whether or not a difference between the first evaluation value and the second evaluation value acquired based on the first evaluation value is larger than the first value;
If it is determined in the determination step that the difference between the first evaluation value and the second evaluation value is larger than the first value, the most focused subject in the second image is determined. And a first control step for controlling the pixel area not to be used as a pixel area when generating an image focused on the plurality of subjects.   15. A computer-readable program for causing a computer to execute the control method for an imaging apparatus according to claim 13 or 14.

Images