JP2010050730A - Imaging apparatus and defect correction apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten time required for correcting a defect occurring in an image. <P>SOLUTION: An imaging apparatus includes: an imaging device which converts light into signal charges; a storage means for storing information indicating the defect of the imaging device as defect information; a division means for dividing the image to be generated based on the signal charges from the imaging device into a plurality of areas; an information acquisition means for acquiring information in the image in the areas divided by the division means as area information; and a defect correction means for specifying an area where a defective pixel is generated among the plurality of areas based on the defect information, and correcting an output signal from the defective pixel based on the area information obtained from the specified area. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an imaging apparatus and a defect correction apparatus.

  2. Description of the Related Art Digital cameras that acquire still images and moving images by using an image sensor such as a CCD (Charge Coupled Device) and a CMOS (Complementary Metal-Oxide Semiconductor) are widely used. 2. Description of the Related Art In recent years, digital cameras that can perform fine processing and acquire high-pixel images have been provided due to advances in semiconductor processes.

In an image acquired by a digital camera, due to a local defect of the semiconductor in the image sensor described above, a pixel that can only obtain an output value that is out of specification, a pixel that does not obtain any output, or a pixel whose output value is always saturated, etc. Defective pixels may occur. In view of this, a technique for correcting a defect occurring in an image (hereinafter, defect correction) has been proposed. Here, a pixel that outputs an abnormal signal is referred to as a “defective pixel”, and a display defect that occurs in an image due to a signal from the pixel when imaged is referred to as a “defective pixel”. There is a case.
JP 2006-174497 A

  However, such defect correction is generally performed uniformly regardless of the relative position between the subject in the image and the defective pixel, the scene mode set at the time of shooting, etc. Therefore, when defect correction is performed on an image with a high pixel, there is a problem that the load of defect correction is large and time is required for defect correction.

  The present invention has been invented in order to solve the above-described problems, and an object thereof is to provide an imaging apparatus and a defect correction apparatus capable of shortening the time required for defect correction.

  An image pickup apparatus according to a first aspect of the present invention is based on an image pickup element that converts light into a signal charge, storage means that stores information indicating a defective pixel of the image pickup element as defect information, and the signal charge from the image pickup element. A dividing unit that divides a generated image into a plurality of regions, an information acquisition unit that acquires information in the image in the region divided by the dividing unit as region information, and a defect occurs in the plurality of regions. And a defect correcting means for specifying an area based on the defect information and correcting an output signal from the defective pixel based on the area information obtained from the specified area. .

  In a second aspect based on the first aspect, the area information is based on at least one of information indicating a focus state in the image in the area and information indicating a luminance change amount in the image in the area. It is characterized by becoming.

  According to a third invention, in the first or second invention, importance determination means for determining the importance of correction for the defect occurring in the region based on at least the region information acquired from the region, In addition, the defect correction means corrects an output signal from the defective pixel using a correction content that matches the importance of the correction determined by the importance determination means.

  According to a fourth invention, in any one of the first to third inventions, the defect information includes position information indicating a position of a defective pixel in the imaging element.

  In a fifth aspect based on any one of the first to third aspects, the defect information includes, in addition to the position information, information indicating the degree of the defect, information indicating the size of the defect, or the defect. It is characterized by comprising at least one piece of information indicating the importance of the part where the occurrence occurs.

  According to a sixth aspect of the present invention, there is provided a defect correction apparatus that divides an image generated based on a signal charge from an image sensor that converts light into a signal charge into a plurality of regions, and a region divided by the dividing unit. Information acquisition means for acquiring information in the image as region information; and a region where a defect occurs among the plurality of regions is specified based on information indicating a defect of the image sensor, and at least from the specified region And defect correcting means for correcting an output signal from the defective pixel based on the obtained area information.

  According to the present invention, the processing time required for defect correction can be shortened.

  FIG. 1 is a diagram showing a configuration of a digital camera embodying the present invention. The digital camera 10 includes a CPU 11, a ROM 12, a RAM 13, and the like. The CPU 11 executes the control program 14 stored in the ROM 12 to comprehensively control each unit of the digital camera 10. In addition to the control program 14, the ROM 12 stores data such as defect information 51 described later. The RAM 13 temporarily stores an operator generated when the digital camera 10 is controlled.

  The imaging optical system 15 includes a plurality of lenses including a photographing lens, a zoom lens, a focus lens, and the like. For example, a CCD or a CMOS is used as the image sensor 16. The image sensor 16 acquires an image signal by converting the light beam transmitted through the imaging optical system 15 into a signal charge (photoelectric conversion). Below, the case where CCD is used as the image pick-up element 16 is demonstrated.

  As shown in FIG. 2, in the imaging device 16, photoelectric conversion units 21 made of, for example, photodiodes are arranged in a matrix on the upper surface of a semiconductor substrate 22. In addition to the photoelectric conversion unit 21, the semiconductor substrate 22 includes a transistor, a gate unit, a vertical transfer unit, a horizontal transfer unit, an output amplifier, and the like (not shown).

  On the upper surface of the semiconductor substrate 22 on which the photoelectric conversion portions 21 are arranged, a light shielding film layer 23 is formed, and a color filter layer 24 and a microlens layer 25 are formed. In the color filter layer 24, red (R), green (G), and blue (B) color filters are arranged according to a known Bayer array. The light transmitted through the color filter layer 24 is color-separated into red (R), green (G), and blue (B) color lights, and then irradiated to the photoelectric conversion units 21. Accordingly, each photoelectric conversion unit 21 accumulates signal charges based on any one of the color-separated color lights. The accumulated signal charges are transferred to the horizontal transfer unit by the vertical transfer unit, and then transferred to the output amplifier by the horizontal transfer unit. The output amplifier converts the transferred signal charge into a voltage (electric signal) and outputs it. In addition, since the accumulation amount of the signal charge is proportional to the luminance value of light, the voltage value output from the imaging element 16 indicates the luminance value.

  Although not shown in the cross-sectional view of the image sensor 16 shown in FIG. 2, a plurality of focus detectors 31 are provided on the light receiving surface of the image sensor 16 to detect the focus state with respect to the subject at the time of shooting. The focus detection unit 31 is provided in the imaging element 16 so as to correspond to each of a plurality of areas obtained by dividing an image acquired by imaging.

  Returning to FIG. 1, the electrical signal output from the image sensor 16 is output to the A / D converter 35. The A / D converter 35 A / D converts the electrical signal output from the image sensor 16. The electric signal is digitized by A / D conversion by the A / D converter 35. The digitized electrical signals are collected for each frame and recorded in the buffer memory 36. Thereby, image data is generated. As described above, since the image signal output from the image sensor 16 is an image signal obtained via the color filter layer 24, the acquired image data is RAW image data. Reference numeral 37 denotes a bus, and each part of the digital camera 10 is electrically connected via the bus 37.

  The defect correction unit 41 corrects pixel defects that occur in the image. Although it is ideal that the image sensor 16 is normal, in reality, a small number of pixels in which abnormality occurs in the transistors, photoelectric conversion units 21, wirings, and the like disposed in the pixels occur. The output signal from the defective pixel causes a defect in the image. The defect correction unit 41 performs defect correction on the obtained image.

  The defect correcting unit 41 has functions of an image dividing unit 45, an information acquiring unit 46, and an importance determining unit 47. The image dividing unit 45 divides an image obtained by photographing into a total of 16 areas, each of which is divided into 4 parts in length and width. Note that the number of image divisions need not be limited to this, and may be set as appropriate. Each of the plurality of divided areas is an area composed of a plurality of pixels.

  The information acquisition unit 46 acquires information in an image (hereinafter referred to as region information) in a plurality of divided regions. The area information includes at least one of a focus evaluation value obtained from the focus detection unit 31 described above or a luminance change amount (hereinafter referred to as an edge amount) in each area. In the present embodiment, a case will be described in which both the focus evaluation value and the edge amount are acquired as region information.

  The focus evaluation value is obtained based on the detection value output from the focus detection unit 31 described above. As described above, the focus detection unit 31 is disposed in the imaging element 16 so as to correspond to each of the plurality of divided areas. The information acquisition unit 46 obtains a focus evaluation value using the detection value from the focus detection unit 31. In addition, when there are a plurality of focus detection units 31 in the divided area, it is possible to use an average value of focus evaluation values obtained from the detection values.

  The edge amount is obtained by performing an edge detection process on each of the plurality of regions described above. Here, as the edge detection process, for example, a process using a filter for edge detection such as a Laplacian filter can be cited. The information acquisition unit 46 performs edge detection processing on each of the plurality of regions, thereby obtaining the edge amount in each region.

  The importance determination unit 47 determines the importance of defect correction for a defective pixel. The ROM 12 stores information (hereinafter referred to as defect information) 51 regarding defects of the image sensor 16. The importance level determination unit 47 reads out the defect information 51 stored in the ROM 12 and specifies an area where a defective pixel is generated among a plurality of areas obtained by dividing the image. After specifying the area where the defective pixel is generated, the importance level determination unit 47 refers to the area information of the specified area and determines the importance level of the defect correction. The defect information 51 includes information indicating the position of the defect of the image sensor 16. As described above, pixel defects include abnormalities in the photoelectric conversion unit 21, transistors, wirings, and the like. Therefore, the defect pixel position includes the position (address) of the defective pixel described above.

  The image processing unit 55 performs image processing such as Bayer interpolation, contour compensation, gamma correction, and white balance adjustment on the image data that has been subjected to defect correction by the defect correction unit 41. Since these image processes are well known, the details thereof are omitted here. Further, the image processing unit 55 generates thumbnail image data or compressed image data in a compression format such as the JPEG method from the image processed image data.

  The LCD 56 displays an image obtained by photographing, a through image captured by the image sensor 16 when not photographing, and the like. In addition to this, the LCD 56 displays a menu image for setting the shooting conditions and the like in the digital camera 10. The LCD 56 is controlled by a display control unit 57. The operation unit 58 includes a release button, a cross key, and the like.

  A storage medium 59 such as a memory card is detachable from the digital camera 10. When the storage medium 59 is attached to the digital camera 10, they are electrically connected via the media controller 60. With this connection, the CPU 11 can perform a process of recording the acquired image data in the storage medium 59 and a process of reading out the image data stored in the storage medium 59. When recording the acquired image data in the storage medium 59, the CPU 11 stores an image file in which information such as the shooting conditions and the type of the digital camera is collected in addition to the above-described thumbnail image data and compressed image data. After the generation, it is recorded in the storage medium 59 via the media controller 60.

  Next, the flow of defect correction processing will be described based on the flowchart of FIG.

  Step S101: Processing for acquiring an image. An image is acquired by executing the processing of step S101, and a detection value for detecting the focus state is acquired from each of the focus detection units 31 provided in the image sensor 16.

  Step S102: This is a process for determining whether there is defect information. The CPU 11 refers to the ROM 12. As described above, since the defect information 51 is information indicating a defect of the image sensor 16, if the image sensor 16 having a defective pixel is incorporated in the digital camera 10, the defect information 51 is stored in the ROM 12 at the time of manufacture. Is done. In this case, the determination process in step S102 is Yes, and the process proceeds to step S103. On the other hand, if no defect has occurred, that is, if the normal image sensor 16 is incorporated in the digital camera 10, the defect information 51 is not stored in the ROM 12. In this case, the determination in step S102 is No, and the defect correction ends.

  Step S103: a process of dividing the acquired image into a plurality of regions. The defect correction unit 41 divides the obtained image into a total of 16 regions, each divided into 4 parts.

  Step S104: This is a process of acquiring a focus evaluation value for each of the plurality of divided areas. As described above, since the detection value is acquired from each of the focus detection units 31 provided in the image sensor 16 when the process of step S101 is performed, the defect correction unit 41 acquires the detected value. Is used to obtain a focus evaluation value in each of the plurality of divided areas. The obtained focus evaluation values are stored in the RAM 13 in association with the target areas.

  Step S105: This is a process of acquiring the edge amount for each of the plurality of divided areas. The defect correction unit 41 obtains the edge amount of each region by performing edge detection processing for each of the plurality of divided regions. The obtained edge amount is stored in the RAM 13 in association with the target area.

  Step S106: This is a process for identifying a region where a defect occurs in the image. The ROM 12 stores defect information 51 in advance. The defect correction unit 41 reads the defect information 51 from the ROM 12. The defect information 51 is information indicating a defect of the image sensor 16. By using the defect information 51, the defect correction unit 41 can specify a region where a defect occurs in the image from a plurality of regions.

  Step S107: This is a process for determining the importance of defect correction in the area specified based on the focus evaluation value and the edge amount. By performing the process of step S107, the importance of defect correction is determined for a region where a defect occurs among a plurality of regions obtained by dividing an image. For example, a flag “1” indicating an importance level is attached to a region having a high importance level. Further, a flag “2” indicating importance is attached to a region having a medium importance, and a flag “3” indicating importance is attached to a region having a low importance. Note that the processing in step S107 is also executed by the defect correction unit 41. Details of the processing in step S107 will be described later.

  Step S108: This is a process for performing defect correction according to importance. In step S107, since the importance of defect correction is determined for a region where a defect occurs in the image, defect correction in accordance with the importance of defect correction is performed on the output signal from the defective pixel. . A plurality of different defect correction programs (not shown) are stored in advance in the ROM 12, and defect correction is executed after selecting a defect correction program according to the importance of defect correction from among these defect correction programs. .

  Hereinafter, the processing content of step S107 is demonstrated using the flowchart of FIG.

  Step S201: This is a process for determining whether or not the focus evaluation value of an area where a defect occurs in an image is larger than a threshold value. The defect correction unit 41 reads a focus evaluation value corresponding to a region where a defect occurs in the image from the RAM 13, and compares this focus evaluation value with a preset threshold value. This threshold value is a value obtained by conducting experiments and evaluations in advance. When it is determined that the focus evaluation value of the area where the defect occurs is larger than the threshold value (when the process of step S201 is Yes), the process proceeds to step S202. On the other hand, when it is determined that the focus evaluation value of the area where the defect occurs is smaller than the threshold value (when the process of step S201 is No), the process proceeds to step S205.

  Step S202: This is a process for determining whether or not the edge amount of the area where the defect occurs is larger than the threshold value. The defect correction unit 41 generates defective pixels. The edge amount corresponding to the region is read from the RAM 13, and this focus evaluation value is compared with a preset threshold value. This threshold value is a value obtained by conducting experiments and evaluations in advance. When it is determined that the edge amount of the area where the defect occurs is larger than the threshold (when the process of step S202 is Yes), the process proceeds to step S203. On the other hand, when it is determined that the edge amount of the area where the defect occurs is smaller than the threshold value (when the process of step S202 is No), the process proceeds to step S211.

  Step S203: This is a process for setting the flag “1” as the importance in defect correction. The area where the process of step S203 is executed is an area where the main subject is in focus. In such an area, since the importance of defect correction becomes high, “1” is set as a flag indicating the importance for such an area. When a defective pixel is generated in the area where the flag “1” is set, the defect correction processing content is that the obtained image data is RAW image data, and therefore the same color arranged at the periphery of the defective pixel. Processing contents such as performing a direction determination using a difference between pixel values of pixels (in this case, an output signal from the pixel, and a luminance value in this case), and interpolating the pixel values of defective pixels based on the result of the direction determination. It is done.

  On the other hand, when the result of step S202 is No, the process proceeds to step S204.

  Step S204: This is a process of setting the flag “2” as the importance in defect correction. The area where the process of step S204 is executed is an area where the main subject is not captured although it is in focus. For such an area, the flag “2” is set as the importance of defect correction. When a defective pixel is generated in the area set to the flag “2”, the defect correction processing content for the defective pixel is, for example, an average of pixel values of pixels of the same color adjacent to the defective pixel. The processing content is as follows.

  Further, if the result of step S201 is No, the process proceeds to step S205.

  Step S205: This is a process of setting the flag “3” as the importance in defect correction. The area where the process of step S205 is executed is an area where the focus is not in focus and the main subject is not reflected. In such an area, since the importance of defect correction is low, the flag “3” is set as the importance of defect correction. When a defective pixel is generated in the region set to the flag “3”, the defect correction processing content for the defective pixel is, for example, any pixel value of a pixel of the same color adjacent to the defective pixel. Examples of processing contents are values.

Hereinafter, a case of an image obtained by photographing a person with a mountain as a background will be described. As shown in FIG. 5A, in the image PI acquired by photographing, image defects DP1, DP2, and DP3 due to defective pixels occur. As shown in FIG. 5B, when the image PI is divided into a total of 16 areas a _{1 to} a ₁₆ by dividing the image PI into 4 parts vertically and horizontally, for example, areas a ₆ and a in which defects DP 1, DP 2 and DP 3 are generated. _9, a ₁₂ is identified, respectively. For example defect DP1, since a pixel corresponding to the face of the subject, the region a ₆ defects DP1 is generated focus evaluation value, the edge amount becomes high. The flag “1” is set as the importance of defect correction for the area a ₆ .

On the other hand, since the area a ₉ where the defect DP2 occurs and the area a ₁₂ where the defect DP3 occurs are areas corresponding to the background, the importance of defect correction with respect to these areas a ₉ and a ₁₂ is a subject area. Lower than A flag “2” is set for these areas. Incidentally, in addition to defect DP1, DP2, DP3 is generated, for example, if the defective area a _10, a ₁₄ occurs, these regions a _10, a ₁₄ from that corresponding to the part of the body of the subject, these The flag “2” is set as the importance of defect correction for the areas a ₁₀ and a ₁₄ , and “3” is set as the importance of defect correction for the areas a ₉ and a ₁₂ corresponding to the background.

  For example, a fine defect correction is performed on an area in which the flag “1” is set as the importance. On the other hand, a defect correction that is simpler than the defect correction for the area for which the flag “1” is set is applied to the area for which the flag “2” or “3” is set as the importance. That is, defect correction in accordance with the importance in defect correction is executed for the corresponding area. Thus, defect correction based on information in the image can be appropriately executed without performing uniform defect correction. In addition, since the correction for the defective pixel is not performed by uniform processing, the time required for the defect correction can be shortened.

  In the present embodiment, the defect information 51 is described using information indicating the position of the defective pixel of the image sensor 16, but in addition to the information indicating the position of the defective pixel of the image sensor 16, the image sensor 16. At least one of information indicating the degree of defect, information indicating the size of the defect of the image sensor 16, and information indicating the importance of the part where the defect occurs may be used as defect information. When the defect information includes any one of the above-described information in addition to the information indicating the position of the photoelectric conversion unit 21 that is a defect, the importance determination unit 47 uses the region information and the defect information to detect the defect. Determine the importance of defect correction for a pixel.

  The information indicating the degree of defect of the image sensor 16 includes the following information. For example, defective pixels of the image sensor 16 have symptoms such as no output value is obtained, the output value is always saturated, or an output is obtained but the output level is different from the normal output level. Information indicating the degree of defect of the image sensor 16 is information indicating the type of defect and the degree of defect.

  Moreover, the following information is mentioned as information which shows the magnitude | size of the defect of the image pick-up element 16. FIG. As described above, the defective pixel of the image sensor 16 is an abnormality of the photoelectric conversion unit 21 or the transistor. In addition, these defects do not always occur in a single part, and a plurality of adjacent parts may be concentrated in a predetermined region. Information indicating the size of the defect of the image sensor 16 is information indicating the number and density of defective pixels.

  The information indicating the importance level of the part where the defect occurs includes information indicating the importance level for each of the divided areas when the light receiving surface of the image sensor 16 is divided into a plurality of areas.

In general, shooting is performed after the position of the main subject is set to the center of the shooting range. As shown in FIG. 6, for example, among the plurality of regions f _{1 to} f ₁₆ obtained by virtually dividing the light receiving surface 16 a of the image sensor 16, the central regions f ₆ , f ₇ , f ₁₀ , and f _{11 are used.} Is set to “1”, and the peripheral areas f ₁ , f ₂ , f ₃ , f ₄ , f ₅ , f ₈ , f ₉ , f ₁₂ , f ₁₃ , f ₁₄ , f ₁₅ , f ₁₆ Set importance to "2". Note that the number of regions obtained by virtually dividing the light receiving surface need not be limited to the above. Also, the importance level for each area need not be limited to the above. For example, the importance level may be changed in accordance with the shooting mode.

When the importance of the image sensor 16 with respect to a site where a defect occurs is included in the defect information, the importance of defect correction for each region in the image is determined as follows. For example, in the case of an image in which the subject is located at the center, the edge amount and the focus evaluation value obtained from the center region in the image are high. In addition, since the importance of defects with respect to the central regions f ₆ , f ₇ , f ₁₀ , and f ₁₁ on the light receiving surface 16a of the image sensor 16 is high, defects are generated for defective pixels that occur in the central region of the image. The importance of correction increases. On the other hand, the edge amount and focus evaluation value obtained from the peripheral area in the image are low, and the peripheral areas f ₁ , f ₂ , f ₃ , f ₄ , f ₅ , f ₈ on the light receiving surface 16a of the image sensor 16 are reduced. , F ₉ , f ₁₂ , f ₁₃ , f ₁₄ , f ₁₅ , f ₁₆ are low in importance, so that the importance of defect correction is low for defects generated in the peripheral area of the image.

  However, at present, the position of the subject in the image is not necessarily located at the center of the image. In such a case, the final defect correction is performed in consideration of both the importance of the plurality of regions obtained by dividing the light receiving surface of the image sensor 16 and the region information including the focus evaluation value and the edge amount in each region. What is necessary is just to determine the importance of. In this case, the importance of defect correction may be determined by giving priority to the area information including the focus evaluation value and the edge amount over the defect information.

  In the present embodiment, the defect correction unit 41 is provided separately from the CPU 11 and the image processing unit 55, but the present invention is not limited to this, and the CPU 11 and the image processing unit 55 include the defect correction unit 41 of the present embodiment. It is also possible to provide a function.

  In the present embodiment, the focus detection unit 31 is provided in the image sensor 16. However, the present invention is not limited to this. For example, a focus detection sensor may be provided separately from the image sensor. In this case, for example, a half mirror may be provided on the optical axis of the imaging optical system, and light reflected by the half mirror may be received by the focus detection sensor. According to this, it is possible to obtain the focus evaluation value by using the output value from the focus detection sensor without providing the focus detection unit in the image sensor.

  In the present embodiment, the defect information 51 indicating the defect of the image sensor 16 manufactured by the semiconductor process is stored in the ROM 12 in advance. However, the present invention is not limited to this, and is acquired by, for example, photographing by the user. It is also possible to detect the position of the defective pixel and the degree of the defect from the image, and store the information of the detected defective pixel in the RAM 13 as defect information. In general, defective pixels of the image sensor 16 often occur during manufacturing or when the lifetime of the image sensor 16 is exceeded, so that the image sensor 16 is defective during the process of using the digital camera 10 by the user. It is rare to occur. However, if information on defective pixels detected from an image acquired by shooting by a user can be stored as defect information, it can be determined whether or not the useful life of the image sensor has been exceeded in the digital camera. If it can be displayed, the user can also recognize it. In such a case, when a defective pixel is newly generated, the defect information stored in the RAM 13 may be updated.

  In the present embodiment, the correction content in the defect correction is changed according to the importance of the defect correction. However, the present invention is not limited to this. For example, the same defect correction processing is used, and the number of pixels used at the time of defect correction It is also possible to change the pixel range and the like according to the importance of defect correction.

  In this embodiment, defect correction for defects in an image is executed based on defect information and area information. In addition to this, defect correction is performed in consideration of a shooting mode set when shooting is performed. It is also possible to execute. In general, a digital camera can be set to one of a plurality of shooting modes such as a landscape shooting mode and a night shooting mode, and is based on defect information and area information regardless of the set shooting mode. Thus, when performing defect correction for defects in an image, defect correction may not be performed properly. For this reason, in addition to defect information and area information, it is possible to perform appropriate defect correction by taking into account the shooting mode set at the time of shooting when performing defect correction.

  In the present embodiment, a digital camera has been described. However, the present invention is applied to a defect correction apparatus and an image processing apparatus having the function of the defect correction unit 41 of the present embodiment in addition to the digital camera. It is also possible. FIG. 7 is a diagram illustrating an example of a defect correction apparatus. The defect correction apparatus 71 has a function of a defect correction unit in the digital camera of this embodiment. That is, when an image is input, image division (reference numeral 75 in the figure), information acquisition (reference numeral 76 in the figure), region specification (reference numeral 77 in the figure) are performed on the input image (hereinafter, input image) PI. ), Determination of importance (reference numeral 78 in the figure), and defect correction (reference numeral 79 in the figure) are executed, and an image (output image PI ′) after defect correction is output. Note that the above-described image division corresponds to step S102 of this embodiment, and information acquisition corresponds to step S103 and step S104 of this embodiment, respectively. Further, region specification corresponds to step S105 of this embodiment, importance determination corresponds to step S106 of this embodiment, and defect correction corresponds to step S107 of this embodiment. Details of these processes are omitted. In this case as well, defect information 80 is required as in the present embodiment. Even when the defect information 80 is stored in the defect correction device 71 in advance, the defect correction device 71 is input when the image PI is input. It may be in the form of being input to.

It is a functional block diagram which shows the structure of a digital camera. It is sectional drawing of an image pick-up element. It is a flowchart which shows the flow of the process at the time of defect correction | amendment. It is a flowchart which shows the flow of the process which determines the importance of defect correction. FIG. 5A is a diagram illustrating an example of an image obtained at the time of shooting, and FIG. 5B is a diagram illustrating a region including a defective pixel when the image is divided. It is a figure which shows the importance of the defect correction | amendment with respect to the photoelectric conversion part used as a defect as defect information. It is a figure which shows an example of a structure of a defect correction apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Digital camera, 16 ... Image sensor, 21 ... Photoelectric conversion part, 31 ... Focus detection part, 41 ... Defect correction part, 45 ... Image division part, 46 ... Information acquisition part, 47 ... Importance determination part, 51 ... Defect Information 71 ... Defect correction device

Claims (6)

An image sensor that converts light into signal charge;
Storage means for storing information indicating defects of the image sensor as defect information;
A dividing unit that divides an image generated based on the signal charges from the image sensor into a plurality of regions;
Information acquisition means for acquiring information in the image in the area divided by the dividing means as area information;
A defect correction that specifies a region where a defective pixel occurs among the plurality of regions based on the defect information and corrects an output signal from the defective pixel based on the region information obtained from the specified region. Means,
An imaging apparatus comprising: The imaging device according to claim 1,
The imaging apparatus according to claim 1, wherein the area information includes at least one of information indicating a focus state in the image in the area and information indicating a luminance change amount in the image in the area. The imaging device according to claim 1 or 2,
Importance determination means for determining importance of correction for the defect occurring in the region based on at least the region information acquired from the region, further comprising:
The imaging apparatus according to claim 1, wherein the defect correcting unit corrects an output signal from the defective pixel using a correction content according to the importance of the correction determined by the importance determining unit. In the imaging device according to any one of claims 1 to 3,
The image pickup apparatus, wherein the defect information includes position information indicating a position of a defect in the image pickup device. The imaging apparatus according to claim 4,
In addition to the position information, the defect information includes at least one piece of information indicating the degree of the defect, information indicating the size of the defect, or information indicating the importance of the part where the defect occurs. An imaging apparatus characterized by the above. A dividing unit that divides an image generated based on a signal charge from an image sensor that converts light into a signal charge into a plurality of regions;
Information acquisition means for acquiring information in the image in each of the areas divided by the dividing means as area information;
An area in which a defect element is generated among the plurality of areas is specified based on information indicating a defect of the imaging element, and output from the defective pixel based on at least the area information obtained from the specified area Defect correcting means for correcting the signal;
A defect correction apparatus comprising:

Images