JP2017143504A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging device for generating a focus assist signal with high accuracy that facilitates the focusing operation during a manual focus operation.SOLUTION: An imaging device includes a distance information calculation unit 5, a high frequency signal extraction unit 1, a focus assist signal generation unit 2, and a signal composing unit 3. The distance information calculation unit 5 calculates distance information of a video signal, and generates a focus range signal from current focus information and the distance information. The high frequency signal extraction unit 1 extracts a high frequency signal of the video signal. The focus assist signal generating unit 2 generates a focus assist signal representing an in-focus area by using the high frequency signal and the focus range signal. The signal composing unit 3 combines the focus assist signal with the video signal to generate a video signal with a focus assist signal.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to an imaging apparatus having a focus assist function for facilitating a user to focus during a manual focus operation.

  In recent years, the depth of field of a lens has become shallow as the resolution of 4K video and the like increases and the size of an image sensor increases. Thereby, focusing operation by manual focus operation is becoming more difficult than before.

  Japanese Patent Application Laid-Open No. 2004-228561 discloses an imaging apparatus that associates the color of the edge in order of the wavelength length according to the edge detection level at the time of manual focus operation. As a result, the color changes according to the degree of focus (degree of focus). Therefore, the user can visually determine the degree of focus.

JP2013-21757A

  In the imaging apparatus described in Patent Document 1, a large edge detection level is used as a guideline for focusing, and in order to easily distinguish the edge detection level visually, the color of the edge is determined according to the edge detection level. Are changed in the order of the wavelength length. However, if the edge detection level is used as a guideline for focusing, the influence of the pattern is greatly affected, so that an accurate focus assist signal may not be obtained. In other words, the edge detection level may be reversed between a slightly blurred edge-prone pattern and a focused edge-prone pattern, so the degree of focus can be determined only by the edge detection level. very difficult.

  The present disclosure has been made to solve such a problem. The present disclosure provides an imaging apparatus that can obtain an accurate focus assist signal by using an edge detection level and distance information.

  The imaging device according to the present disclosure includes a distance information calculation unit, a high-frequency signal extraction unit, a focus assist signal generation unit, and a signal synthesis unit. The distance information calculation unit calculates distance information of the video signal and generates a focusing range signal from the current focus information and distance information. The high frequency signal extraction unit extracts a high frequency signal of the video signal. The focus assist signal generation unit generates a focus assist signal representing the focus area using the high frequency signal and the focus range signal. The signal combining unit combines the focus assist signal with the video signal to generate a video signal with a focus assist signal.

  The imaging apparatus according to the present disclosure is effective for obtaining a focus assist signal with high accuracy.

1 is a block diagram illustrating a configuration of an imaging apparatus according to Embodiment 1 of the present disclosure. The block diagram which shows the image processing performed with the controller of the imaging device in Embodiment 1 of this indication Schematic diagram for explaining the operation of the distance information calculation unit of the imaging apparatus according to the first embodiment of the present disclosure. Schematic diagram for describing a process of generating a focus assist signal in which only in-focus is emphasized in the imaging apparatus according to Embodiment 1 of the present disclosure. Schematic diagram for explaining a process of generating a video signal with a focus assist signal in the imaging apparatus according to Embodiment 1 of the present disclosure. 2 is a block diagram illustrating a configuration related to image processing of an imaging device according to Embodiment 2 of the present disclosure Schematic diagram for explaining the operation of the distance information calculation unit in the case of calculating only representative points in the imaging apparatus according to Embodiment 2 of the present disclosure. FIG. 6 is a schematic diagram for explaining the operation of the interpolation unit in the case of calculating only representative points in the imaging apparatus according to Embodiment 2 of the present disclosure. FIG. 6 is a block diagram illustrating a configuration related to image processing of an imaging apparatus according to Embodiment 3 of the present disclosure. Schematic diagram for explaining an operation of determining an edge vicinity region in the imaging apparatus according to Embodiment 3 of the present disclosure. FIG. 7 is a schematic diagram for explaining an operation of calculating distance information only in the edge vicinity region in the imaging apparatus according to Embodiment 3 of the present disclosure. FIG. 7 is a schematic diagram for explaining an operation of interpolating a focusing range signal in a region other than the vicinity of an edge in the imaging apparatus according to the third embodiment of the present disclosure.

  Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

  The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(Embodiment 1)
The first embodiment will be described below with reference to FIGS.

[1-1. Constitution]
FIG. 1 is a block diagram illustrating a configuration of an imaging apparatus according to Embodiment 1 of the present disclosure.

  FIG. 1 is a block diagram illustrating a configuration of the imaging device 100 according to the first embodiment of the present disclosure. The imaging apparatus 100 includes a lens barrel 102 and a camera body 101. The lens barrel 102 includes an optical system (not shown) including a focus lens and a zoom lens, a diaphragm, and the like. The camera body 101 includes an image sensor 103, a controller 104, and a display unit 105.

  In the present embodiment, the imaging apparatus 100 will be described with a configuration in which the lens barrel 102 and the camera body 101 are integrated. However, the lens barrel 102 is configured by an interchangeable lens, and the interchangeable lens and the camera body are separated. A possible interchangeable lens imaging device may be used.

  The image sensor 103 captures a subject image incident through the lens barrel 102 and generates a video signal. The image sensor 103 is a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Devices) image sensor. The generated video signal is subjected to various image processing by the controller 104. Examples of the various types of image processing include gamma correction processing, white balance correction processing, scratch correction processing, YC (luminance / color difference) conversion processing, electronic zoom processing, and JPEG (Joint Photographic Experts Group) compression processing. However, it is not limited to these. The controller 104 controls the entire imaging apparatus 100 in addition to the image processing described above. The controller 104 may be configured with a hard-wired electronic circuit or a microcomputer using a program. The display unit 105 is disposed on the back surface of the camera body 101. The display unit 105 displays an image indicated by the display video signal processed by the controller 104. The display unit 105 can selectively display both moving images and still images. The display unit 105 can display setting conditions and the like of the entire imaging apparatus 100 in addition to images. The display unit 105 is a liquid crystal monitor or an organic EL (electro-luminescence) monitor.

  FIG. 2 is a block diagram illustrating image processing executed by the controller 104 of the imaging device 100 according to Embodiment 1 of the present disclosure. The imaging apparatus 100 includes a high-frequency signal extraction unit 1, a focus assist signal generation unit 2, a signal synthesis unit 3, a memory circuit unit 4, and a distance information calculation unit 5.

  The inputs to the configuration block shown in FIG. 2 are video signals at different focus positions and focus information related to the focus operation, which are input by the user operating an operation unit (not shown) of the lens barrel 102.

  The high frequency signal extraction unit 1 extracts a high frequency signal of the video signal.

  The distance information calculation unit 5 calculates distance information for each area of the video signal using a DFD (Depth From Defocus) technique. The DFD technology uses two or more video signals at different focus positions, focus information for each video signal, and lens blur information, and based on the difference in the blur method of the video signal, This is a technique for calculating distance information for each.

  The memory circuit unit 4 stores two or more video signals and focus information at different focus positions necessary for the distance information calculation unit 5 to calculate the distance information.

  The focus assist signal generation unit 2 uses the high frequency signal generated by the high frequency signal extraction unit 1 and the focus range signal generated by the distance information calculation unit 5 to generate a focus assist signal that emphasizes only the focus area. Generate.

  The signal synthesizer 3 synthesizes the focus assist signal in which only the in-focus generated by the focus assist signal generator 2 is emphasized with the original video signal.

  The video signal generated by the signal synthesis unit 3 is displayed on the display unit 105.

[1-2. Operation]
The operation of the imaging apparatus 100 configured as described above will be described. The imaging apparatus 100 outputs a video signal with a focus assist signal obtained by synthesizing a focus assist signal that emphasizes only the video signal in the focused area so that the focused video area of the video signal can be easily identified. For example, a red edge is synthesized only in the focused area of the video signal, and a video signal is output so that the focused video area can be seen at a glance. Hereinafter, each operation will be described in detail.

  A case where two dolls placed at different distances are photographed will be described. A doll having a square torso on the right side of the screen when the photographer views the screen of the display unit 105 is placed at a distance from the imaging device 100. A doll having an elliptical torso on the left side of the screen when the photographer views the screen of the display unit 105 is placed at a short distance from the imaging device 100. Consider a case where the focus is moved from a doll placed far from the imaging device 100 to a doll placed closer to the imaging device 100. In FIG. 3, a focused doll is indicated by a black line, and a focused doll is indicated by a thick gray line. In an image with a far focus position, the doll on the right side of the screen is in focus, and the doll on the left side of the screen is blurred. In the image with close focus, the doll on the right side of the screen is blurred and the doll on the left side of the screen is in focus. Currently, the image is close to the focus position.

  The process of generating a video signal with a focus assist signal at this time will be described with reference to FIGS.

  FIG. 3 is a schematic diagram for explaining the operation of the distance information calculation unit 5 of the imaging apparatus 100 according to Embodiment 1 of the present disclosure.

  The calculation of DFD requires two or more video signals at different focus positions, focus information for each video signal, and lens blur information. The video signal when the focus position is moved from a far place to a close place is always input to the memory circuit unit 4 and appropriately stored. When the DFD calculation is performed from the two images of the image with the far focus position stored in the memory circuit unit 4 and the image with the close current focus position and the lens blur information stored in advance, the distance information is obtained. Is calculated. In the distance information of FIG. 3, a region where a doll having an elliptical body on the left side of the screen is close to the imaging device 100, and a region where a doll having a square body on the right side of the screen is far from the imaging device 100. Represents the area. From the current focus information and distance information, it is possible to determine a region focused on the current video. The focused area is an area where the focus range signal is shown in black in the right block of FIG. 3 in FIG. In this way, the distance information calculation unit 5 outputs a focus range signal.

  FIG. 4 is a schematic diagram for explaining a process of generating a focus assist signal in which only in-focus is emphasized in the imaging apparatus 100 according to Embodiment 1 of the present disclosure. A focus assist signal generation operation in which only in-focus is emphasized will be described with reference to FIG.

  The high-frequency signal extraction unit 1 performs high-pass filter processing and extracts a high-frequency signal of the video signal.

  Since the current video signal is an image with a close focus position, the doll on the left side of the screen is in focus and the doll on the right side of the screen is out of focus. As the focus is adjusted, the high-frequency signal of the video increases, so when high-pass filter processing is performed on this video, a signal such as the edge portion of the doll on the left side of the screen is extracted as shown in the high-frequency signal (edge signal) of FIG. Get. However, because this high-frequency signal is also greatly affected by the pattern, the edge part of the doll on the right side of the screen is extracted as shown in the edge signal in FIG. 4 even if the pattern with strong contrast is slightly out of focus. Such a signal is also detected.

  The focus assist signal generation unit 2 uses the focus range signal from the distance information calculation unit 5 to extract the edge signal of only the focus range, and emphasizes only the in-focus. (FA signal) is generated. In FIG. 4, as a method for emphasizing, a signal in which a high-frequency signal portion in a focused area is displayed with a double line is generated.

  Note that the emphasis method is not limited to the double line, and may be converted into red or blue, and any emphasis method may be used if a high-frequency signal extracted using the focus range signal is used. Also good.

  FIG. 5 is a schematic diagram illustrating a process of generating a video signal with a focus assist signal in the imaging apparatus 100 according to Embodiment 1 of the present disclosure.

  As described above with reference to FIG. 4, since the focus assist signal in which only the in-focus is emphasized is generated, the video signal with the focus assist signal is generated by synthesizing with the original video signal.

  The synthesis method may be addition, replacement, or other methods.

[1-3. Effect]
As described above, in the present embodiment, the imaging apparatus 100 includes the distance information calculation unit 5, the high frequency signal extraction unit 1, the focus assist signal generation unit 2, and the signal synthesis unit 3. The distance information calculation unit 5 calculates distance information of the video signal and generates a focusing range signal from the current focus information and distance information. The high frequency signal extraction unit 1 extracts a high frequency signal of the video signal. The focus assist signal generation unit 2 generates a focus assist signal representing the focus area using the high frequency signal and the focus range signal. The signal combining unit 3 combines the focus assist signal with the video signal to generate a video signal with a focus assist signal.

  Thereby, it is possible to synthesize a focus assist signal in which only an in-focus area is emphasized. For this reason, an accurate focusing operation becomes possible.

  In the present embodiment, the imaging apparatus 100 generates a focus assist signal based on the high-frequency signal of the video signal.

  Thereby, the generated video signal with a focus assist signal becomes a high-definition video signal. For this reason, a focusing operation without a sense of incongruity becomes possible.

(Embodiment 2)
Embodiment 2 divides a video area into blocks, calculates distance information selectively only at representative points, and generates a focusing range signal adapted to the entire video by interpolation from distance information only at representative points. However, this is different from the first embodiment. Hereinafter, the second embodiment will be described with reference to FIGS. 6 to 8 focusing on the differences from the first embodiment.

[2-1. Constitution]
FIG. 6 is a block diagram illustrating a configuration related to image processing of the imaging apparatus 100 according to the second embodiment of the present disclosure. In FIG. 6, the same reference numerals are used for the same components as those in FIG.

  The imaging apparatus 100 according to Embodiment 2 further includes a position selection signal generation unit 6 and an interpolation unit 7.

  The position selection signal generation unit 6 divides the video area into blocks, and generates a distance calculation on / off (ON / OFF) signal so that only representative points are selectively calculated.

  The interpolation unit 7 performs interpolation so that the calculation result of the representative point is applied to the entire block obtained by dividing the video area.

[2-2. Operation]
The operation of the imaging apparatus 100 configured as described above will be described below.

  FIG. 7 is a schematic diagram for explaining the operation of the distance information calculation unit 5 when only the representative point is calculated in the imaging device 100 according to the second embodiment of the present disclosure.

  As in the first embodiment, a case where two dolls placed at different distances from the imaging device 100 are photographed will be described. A doll having a square torso on the right side of the screen is placed at a distance from the imaging device 100, and a doll having an elliptical body on the left side of the screen is placed at a distance from the imaging device 100. Consider a case where the focus is moved from a distant doll to a close doll.

  The process of generating a focusing range signal for the entire video signal in this case will be described with reference to FIGS.

  In FIG. 7, the video area is divided into 2 × 2 pixel blocks, and the upper left pixel is used as a representative point of the block. That is, in the 2 × 2 pixel block, only distance information for the upper left pixel is calculated. Further, as in the first embodiment, the current focus information is used to determine a region focused on the current video, and a focus range signal for only the upper left is output in a 2 × 2 block.

  FIG. 8 is a schematic diagram for explaining the operation of the interpolation unit 7 when only the representative points are calculated in the imaging apparatus according to the second embodiment of the present disclosure.

  From the focus range signal of the representative point, a focus range signal of the remaining pixel area of the block is generated by interpolation processing. In FIG. 8, the focus range signal of the representative point is output as it is as the focus range signal of the remaining pixel area of the block.

  The focus range signal of the entire video signal is used in the same manner as in the first embodiment in order to determine the in-focus area.

  Note that the region divided into blocks may not be a 2 × 2 pixel region, and may be a 4 × 4 pixel or an 8 × 4 pixel.

  The representative point of the area divided into blocks may not be the upper left pixel.

  Note that any interpolation method may be used. For example, the interpolation method may be calculated by linear interpolation processing from the in-focus range signals of the representative points in the vicinity.

  As for the order of interpolation processing, the focus range signal may be calculated based on the current focus information after the distance information of only the representative point is interpolated to calculate the distance information of the entire video signal.

  Since the high-frequency signal extraction unit 1, the focus assist signal generation unit 2, and the signal synthesis unit 3 are the same operations as those in the first embodiment, description thereof is omitted.

[2-3. Effect]
As described above, in the present embodiment, the imaging apparatus 100 may further include the position selection signal generation unit 6 and the interpolation unit 7. The position selection signal generation unit 6 divides the video area into blocks and generates a distance calculation on / off signal so as to calculate the representative points of the divided block areas. The interpolation unit 7 obtains a focusing range signal for the entire region in accordance with the signal output from the position selection signal generation unit.

  Thereby, the calculation amount which calculates distance information can be decreased. Therefore, power consumption of the circuit, circuit scale, or both can be reduced.

  Further, when the calculation amount is reduced, the calculation is completed earlier, and the video delay of the imaging apparatus 100 can be reduced.

(Embodiment 3)
In Embodiment 3, the edge vicinity region is determined from the video region, and the distance information is selectively calculated only in the edge vicinity region. In a region determined not to be an edge vicinity region, a video signal with a focus assist signal is generated using a focus range signal that is forcibly set as a non-focus range. These points are different from the first and second embodiments. Hereinafter, the third embodiment will be described with reference to FIGS. 9 to 12 with a focus on differences from the first and second embodiments.

[3-1. Constitution]
FIG. 9 is a block diagram illustrating a configuration related to image processing of the imaging apparatus 100 according to Embodiment 3 of the present disclosure. 9, the same reference numerals are used for the same configurations as those in FIGS. 2 and 6.

  The imaging apparatus 100 according to the third embodiment further includes an edge vicinity region determination unit 8 and an edge vicinity region outside interpolation unit 9 in addition to the configuration of the first embodiment shown in FIG.

  The edge vicinity area determination unit 8 determines an edge vicinity area of the video area, and generates edge vicinity area information so as to selectively calculate distance information only in the edge vicinity area. As a method of determining the edge vicinity region, a pixel whose amount of change in luminance level of a vertical or horizontal line of the pixel is a predetermined level or more may be set as the edge vicinity region.

  The edge vicinity region outside interpolation unit 9 forcibly defocuses the focus range signal in the region not near the edge.

[3-2. Operation]
The operation of the imaging apparatus 100 configured as described above will be described.

  Similar to the first embodiment, a case where two dolls placed at different distances are photographed will be described. A doll having a square torso on the right side of the screen is placed at a distance from the imaging device 100, and a doll having an elliptical body on the left side of the screen is placed at a distance from the imaging device 100. Consider the case where the focus is moved from a distant doll to a close doll.

  The process of generating the focusing range signal for the entire video signal in this case will be described with reference to FIGS.

  FIG. 10 is a schematic diagram for explaining an operation of determining an edge vicinity region in the imaging apparatus according to Embodiment 3 of the present disclosure.

  The edge vicinity region determination unit 8 performs high-pass filter processing on the video signal and extracts an edge signal. Since the high-pass filter process detects the amount of change in the video signal, the signal level changes at the edge portion of the video, and the signal level becomes substantially constant in a flat region other than the edge. The reason why the signal level is not completely constant in the flat region is that there is slight noise or uneven color. The edge vicinity region determination unit 8 also considers a noise component included in the video signal, and determines whether the region is an edge vicinity region by performing level determination of the edge signal.

  Note that the method for determining the edge vicinity region is not limited to the above. For example, a contraction process, an expansion process, or a noise removal process may be added to stabilize the determination result. Furthermore, a range within a predetermined pixel, for example, within 10 pixels, from the edge obtained by the above method may be set as the edge vicinity region.

  FIG. 11 is a schematic diagram for explaining an operation of calculating distance information only in the edge vicinity region in the imaging apparatus according to Embodiment 3 of the present disclosure.

  Based on the edge vicinity area information, distance information is calculated only for the edge vicinity area. Accordingly, in the distance information of only the edge vicinity area shown in FIG. 11, the area other than the edge vicinity area (gray part) is the area where the distance information is not calculated, and the edge vicinity part of the doll having the ellipse body on the left side of the screen is imaged. A region near the device 100 and a portion near the edge of the doll having a square torso on the right side of the screen are regions far from the imaging device 100. The focus range is determined from the distance information of only the edge vicinity region and the current focus information. As a result, an in-focus range signal only in the edge vicinity region is obtained. The entire image is discriminated into a black focused area, a white non-focused area, and a gray uncalculated area.

  FIG. 12 is a schematic diagram for explaining an operation of interpolating a focusing range signal outside the edge vicinity region in the imaging apparatus according to Embodiment 3 of the present disclosure. The focus range signal of the entire image displayed on the screen of the display unit 105 is output by forcibly outputting the focus range signal of the uncalculated area shown in gray, that is, the area outside the edge vicinity area, as the non-focus area. Get.

  The focus range signal of the entire video signal is used in the same manner as in the first embodiment to determine the in-focus area.

  Note that the order of interpolation of the focus range signal outside the edge vicinity region may be immediately after the distance information of the edge vicinity region is calculated.

  Since the high-frequency signal extraction unit 1, the focus assist signal generation unit 2, and the signal synthesis unit 3 perform the same operations as those in the first embodiment, description thereof is omitted.

[3-3. Effect]
As described above, in the present embodiment, the imaging apparatus 100 may further include the edge vicinity region determination unit 8 and the edge vicinity region outside interpolation unit 9. The edge vicinity area determination unit 8 determines an edge vicinity area of the video signal. The edge vicinity region outside interpolation unit 9 calculates distance information only for the edge vicinity region determined by the edge vicinity region determination unit, and interpolates the outside of the edge vicinity region as a non-focused range.

  Thereby, the calculation amount which calculates distance information can be decreased. Therefore, power consumption of the circuit, circuit scale, or both can be reduced.

  When the amount of calculation decreases, the calculation ends earlier, and the video delay of the imaging apparatus 100 can be reduced.

  Further, it is possible to prevent the focus range signal from being in a block shape, and it is possible to obtain a high-definition focus range signal. Therefore, it is possible to perform a focusing operation without a sense of incongruity.

(Other embodiments)
As described above, Embodiments 1 to 3 have been described as examples of the technology in the present disclosure. However, the technology in the present disclosure is not limited to this, and can also be applied to embodiments that have been changed, replaced, added, omitted, and the like. Moreover, it is also possible to combine each component demonstrated in the said Embodiment 1-3 and it can also be set as new embodiment.

  Other embodiments will be illustrated below.

  In the first to third embodiments, high-pass filter processing is used as an example of the high-frequency signal extraction unit. The high-frequency signal extraction unit is not limited to a high-pass filter, and may be any unit that extracts a high-frequency component of a video signal. Therefore, the high-frequency signal extraction unit is not limited to a high-pass filter. In addition to high-pass filter processing, noise removal processing, contraction, expansion processing, and the like may be added.

  In the first to third embodiments, a DFD (Depth From Defocus) technique is used as an example of the distance information calculation unit. However, the distance information calculation unit only needs to calculate the distance information of the video signal. Therefore, the distance information calculation unit is not limited to only processing using the DFD technique. For example, a so-called phase difference detection method may be used. That is, the light flux that has passed through the lens is divided and projected, and the in-focus range signal is obtained by the positional relationship between the two images generated by separately receiving the light that has passed through different paths (for example, the right side and the left side of the lens). Further, as a means for realizing the phase difference detection method, an image sensor having a configuration in which a photodiode for phase difference detection is embedded in the image sensor may be used.

  The above-described embodiments are for illustrating the technique in the present disclosure, and various modifications, replacements, additions, omissions, and the like can be made within the scope of the claims and their equivalents.

  The present disclosure is applicable to an imaging apparatus that performs a manual focus operation. Specifically, the present disclosure can be applied to digital cameras, movies, commercial video cameras, mobile phones with camera functions, smartphones, and the like.

DESCRIPTION OF SYMBOLS 1 High frequency signal extraction part 2 Focus assist signal generation part 3 Signal composition part 4 Memory circuit part 5 Distance information calculation part 6 Position selection signal generation part 7 Interpolation part 8 Edge vicinity area determination part 9 Edge vicinity area outside interpolation part 100 Imaging device 101 Camera body 102 Lens barrel 103 Image sensor 104 Controller 105 Display unit

Claims (4)

A distance information calculation unit that calculates distance information of the video signal and generates a focusing range signal from the current focus information and the distance information;
A high frequency signal extraction unit for extracting a high frequency signal of the video signal;
A focus assist signal generating unit that generates a focus assist signal representing an in-focus area using the high-frequency signal and the in-focus range signal;
A signal combining unit that combines the focus assist signal with the video signal to generate a video signal with a focus assist signal;
An imaging apparatus comprising: The imaging apparatus according to claim 1, wherein the distance information calculation unit calculates the distance information from the video signal captured at different focus positions and information on a current focus position. A position selection signal generator that divides a video area into blocks and generates a distance calculation on / off signal so as to calculate a representative point of the divided block area;
In accordance with a signal output by the position selection signal generation unit, an interpolation unit that interpolates the distance information to obtain a focusing range signal of the entire region;
The imaging apparatus according to claim 1, further comprising: An edge vicinity area determination unit that determines an edge vicinity area of the video signal;
Only the edge vicinity area determined by the edge vicinity area determination unit calculates the distance information, and interpolates outside the edge vicinity area as an out-of-focus area,
The imaging apparatus according to claim 1, further comprising: