JP4902512B2 - Imaging apparatus, control method thereof, and program - Google Patents

Description

  The present invention relates to a technique for embedding digital watermark data in image data captured by an imaging apparatus such as a digital camera.

  Digital cameras have been remarkably improved in performance, size, and weight, and have been widely used in the workplaces such as magazines and newspapers to replace film cameras.

  On the other hand, since it is easy to tamper with digital data so that no trace remains, reliability as evidence of the captured digital image may be a problem. This kind of problem is unlikely to occur if shooting within the range of hobbies by general users, but it is a major problem for shooting that is necessary for business or legal purposes, such as recorded photographs of construction sites and accident sites. It becomes.

  Another problem is that the rights of the copyright holder of the image are not sufficiently protected because copying and distribution are easy.

  Therefore, there is a great expectation for a digital camera that can enhance the evidence ability of the photographed digital image and protect the copyright.

For this purpose, a technique called “digital watermark” has begun to be used. Even if image processing (filtering processing such as blurring processing or sharpness processing) or image format conversion (conversion from JPEG to bitmap, etc.) is applied to digital image data in which predetermined data is embedded by digital watermarking, after processing and conversion The digital watermark data in the image data is not lost. Due to such a property, copyright information is embedded in image data by digital watermark. The copyright information embedded in the electronic watermark can be read out even after the image data is processed and converted, and the copyright can be claimed.
JP 2000-216985 A

  However, conventionally, digital watermark data is embedded in the entire image data representing an image of one frame. Therefore, when a part of the image data in which the digital watermark data is embedded is deleted, there is a possibility that the embedded data cannot be read and reproduced.

  For example, in a digital camera, dust (foreign matter) adhering to an optical element such as an optical low-pass filter disposed in front of the image sensor always appears as a black dot on the image data until the optical element is cleaned. The dust image portion reflected on the image data may be corrected to image data that does not include dust by replacing it with data of surrounding pixels of the same color. When the digital watermark data is embedded in the dust image portion, the digital watermark data is lost by correcting the dust image portion, and the embedded data may not be read.

  In addition, when a person who is a subject is photographed using a flash, the black eye part of the eye may appear red in rare cases. This is called a red-eye photograph, and is a phenomenon in which the red color of blood on the retina is reflected in the photograph when the flash is taken with the pupil open. When it becomes a red-eye photograph, the red-eye part may be corrected with a color close to the original color. Also in this case, if the digital watermark data is embedded in the eye portion, the digital watermark data may be lost by correcting the red-eye portion, and the embedded data may not be read.

  Incidentally, Japanese Patent Laid-Open No. 2000-216985 (Patent Document 1) proposes a method of embedding digital watermark data by designating a plurality of positions. However, in this method, it is cumbersome to specify a plurality of positions, and it is not possible to specify the embedding position of the digital watermark data so as to avoid it after confirming the presence of the above-mentioned dust on the display device of the digital camera. Have difficulty.

  Therefore, the present invention has been made in view of the above-described problems, and an object thereof is to prevent embedded digital watermark data from being lost due to image processing or the like.

  In order to solve the above-described problems and achieve the object, an imaging apparatus according to the present invention includes an imaging unit that photoelectrically converts a subject image to generate an image signal, and among the image signals generated by the imaging unit. Detecting means for detecting a correction region that is a region that may be corrected as a region in which a shadow of a foreign substance attached to an optical element disposed in front of the imaging unit is reflected by subsequent image processing; and A watermark information embedding unit for embedding digital watermark information in an image signal, and a correction area detected by the detection unit is excluded from an area to be embedded with the digital watermark information, and the digital watermark information is embedded in the image signal. Control means for controlling the watermark information embedding means.

  According to another aspect of the present invention, there is provided a control method for an image pickup apparatus, the image pickup means for photoelectrically converting a subject image to generate an image signal, and the image pickup by the subsequent image processing of the image signal generated by the image pickup means. Detecting means for detecting a correction region that is a region that may be corrected as a region in which a shadow of a foreign substance attached to an optical element disposed in front of the means is reflected; and a watermark for embedding digital watermark information in the image signal And an information embedding unit for controlling the imaging apparatus, wherein the correction area detected by the detection unit is excluded from an area to be embedded with the digital watermark information, and the digital watermark information is added to the image signal. A control step of controlling the watermark information embedding unit so as to be embedded is provided.

  According to the present invention, it is possible to prevent embedded digital watermark data from being lost due to image processing or the like.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram illustrating a configuration of a digital camera as an imaging apparatus according to an embodiment of the present invention.

  In FIG. 1, reference numeral 100 denotes a digital camera. 10 is a photographing lens, 12 is a shutter having a diaphragm function, 14 is an image sensor that photoelectrically converts a subject image formed by the photographing lens 10 to generate an image signal, and 16 is an analog image signal output from the image sensor 14. Is an A / D converter for converting the signal into a digital signal. Reference numeral 14 a denotes an optical element such as an optical low-pass filter disposed in front of the image sensor 14. Foreign matters such as dust adhering to the surface of the optical element 14a appear in the image obtained by the imaging element 14. Further, in the present embodiment, the structure in which the photographing lens 10 is fixed to the digital camera 100 is shown, but the digital camera 100 may be a single-lens reflex type camera in which the photographing lens 10 can be replaced. Particularly, in the case of a single-lens reflex camera, foreign matter such as dust is likely to enter the camera body when the lens is exchanged. Therefore, countermeasures when foreign matter such as dust adheres to the optical element 14a is an important issue.

  A timing generation circuit 18 supplies a clock signal and a control signal to the image sensor 14, the A / D converter 16, and the D / A converter 26, and is controlled by the memory control circuit 22 and the system control circuit 50.

  An image processing circuit 20 performs predetermined pixel interpolation processing and color conversion processing on the data from the A / D converter 16 or the data from the memory control circuit 22.

  The image processing circuit 20 performs predetermined calculation processing using the captured image data, and the system control circuit 50 controls the exposure control unit 40 and the distance measurement control unit 42 based on the obtained calculation result. TTL (through-the-lens) AF (autofocus) processing, AE (automatic exposure) processing, and EF (flash pre-emission) processing are performed.

  Further, the image processing circuit 20 performs predetermined arithmetic processing using captured image data, and also performs TTL AWB (auto white balance) processing based on the obtained arithmetic result.

  A memory control circuit 22 controls the A / D converter 16, the timing generation circuit 18, the image processing circuit 20, the image display memory 24, the D / A converter 26, the memory 30, and the compression / decompression circuit 32.

  Data from the A / D converter 16 passes through the image processing circuit 20 and the memory control circuit 22, or data from the A / D converter 16 passes directly through the memory control circuit 22 to the image display memory 24 or the memory 30. Is written to.

  Reference numeral 24 denotes an image display memory, 26 denotes a D / A converter, 28 denotes an image display unit including a TFT LCD, and the image data for display written in the image display memory 24 passes through the D / A converter 26. Displayed by the image display unit 28.

  If the image data captured using the image display unit 28 is sequentially displayed, the electronic viewfinder function can be realized.

  The image display unit 28 can arbitrarily turn on / off the display according to an instruction from the system control circuit 50. When the display is turned off, the power consumption of the digital camera 100 can be significantly reduced. I can do it.

  Reference numeral 30 denotes a memory for storing captured still images and moving images, and has a storage capacity sufficient to store a predetermined number of still images and a moving image for a predetermined time. Thereby, even in the case of continuous shooting or panoramic shooting in which a plurality of still images are continuously shot, it is possible to write a large amount of images to the memory 30 at high speed.

  The memory 30 can also be used as a work area for the system control circuit 50.

  Reference numeral 32 denotes a compression / decompression circuit that compresses and decompresses image data by adaptive discrete cosine transform (ADCT) or the like, reads an image stored in the memory 30, performs compression processing or decompression processing, and stores the processed data in the memory 30. Write to.

  Reference numeral 40 denotes an exposure control unit that controls the shutter 12 having an aperture function, and has a flash light control function in cooperation with the flash 48.

  Reference numeral 42 denotes a distance measurement control unit that controls focusing of the photographing lens 10, reference numeral 44 denotes a zoom control unit that controls zooming of the photographing lens 10, and reference numeral 46 denotes a barrier control unit that controls the operation of the protection unit 102 serving as a barrier.

  A flash 48 has an AF auxiliary light projecting function and a flash light control function.

  The exposure control unit 40 and the distance measurement control unit 42 are controlled using the TTL method. Based on the calculation result obtained by calculating the captured image data by the image processing circuit 20, the system control circuit 50 performs the exposure control unit 40 and the distance measurement. The controller 42 is controlled.

  A system control circuit 50 controls the entire digital camera 100, and a memory 52 stores constants, variables, programs, and the like for operation of the system control circuit 50.

  Reference numeral 54 denotes a display unit such as a liquid crystal display device or a speaker that displays an operation state, a message, and the like using characters, images, sounds, and the like in accordance with execution of a program in the system control circuit 50. The display unit 54 is installed at a single or a plurality of positions near the operation unit of the digital camera 100 so that the display unit 54 can be visually recognized.

  In addition, the display unit 54 is partially installed in the optical viewfinder 104.

  Among the display contents of the display unit 54, what is displayed on the LCD or the like includes single shot / continuous shooting display, self-timer display, compression rate display, number of recorded pixels, number of recorded pixels, number of remaining images that can be captured, shutter There are speed display, aperture value display, exposure compensation display, and so on. In addition, flash display, red-eye reduction display, macro shooting display, buzzer setting display, clock battery level display, battery level display, error display, information display with multiple digits, display / removal status display of recording medium 200, communication I / F operation display, date / time display, etc.

  Further, among the display contents of the display unit 54, what is displayed in the optical viewfinder 104 includes in-focus display, camera shake warning display, flash charge display, shutter speed display, aperture value display, exposure correction display, and the like.

  Reference numeral 56 denotes an electrically erasable / recordable nonvolatile memory such as an EEPROM.

  Reference numerals 60, 62, 64, 66, 68, and 70 denote operation units for inputting various operation instructions of the system control circuit 50. A single unit such as a switch, dial, touch panel, pointing by line-of-sight detection, a voice recognition device, or the like Consists of multiple combinations.

  Here, a specific description of these operation units will be given.

  Reference numeral 60 denotes a mode dial switch, which can switch and set various function modes such as power-off, automatic shooting mode, shooting mode, panoramic shooting mode, playback mode, multi-screen playback / erase mode, and PC connection mode.

  Reference numeral 62 denotes a shutter switch SW1, which is turned ON during the operation of a shutter button (not shown), and performs AF (auto focus) processing, AE (auto exposure) processing, AWB (auto white balance) processing, EF (flash pre-flash) processing, and the like. Instruct to start operation.

  Reference numeral 64 denotes a shutter switch SW2, which is turned on when an operation of a shutter button (not shown) is completed, and exposure processing and image processing for writing a signal read from the image sensor 14 to the memory 30 via the A / D converter 16 and the memory control circuit 22. Instructs the start of a series of processing operations such as development processing using arithmetic operations in the circuit 20 and the memory control circuit 22, reading out image data from the memory 30, compression in the compression / decompression circuit 32, and writing into the recording medium 200 To do.

  Reference numeral 66 denotes an image display ON / OFF switch that can set ON / OFF of the image display unit 28. With this function, when photographing using the optical viewfinder 104, it is possible to save power by cutting off the current supply to the image display unit 28 including a TFT LCD or the like.

  Reference numeral 68 denotes a quick review ON / OFF switch, which sets a quick review function for automatically reproducing image data taken immediately after photographing.

  Reference numeral 70 denotes an operation unit composed of various buttons, a touch panel, and the like. A menu button, a set button, a macro button, a multi-screen playback page break button, a flash setting button, a single shooting / continuous shooting / self-timer switching button, menu movement + (plus) Button, menu movement-(minus) button, menu item movement + (plus) button, menu item movement-(minus) button, playback image movement + (plus) button, playback image movement-(minus) button, shooting image quality selection button , Exposure compensation button, date / time setting button, and the like.

  A power control unit 80 includes a battery detection circuit, a DC-DC converter, a switch circuit that switches a block to be energized, and the like. Then, the presence / absence of a battery, the type of battery, the remaining battery level are detected, the DC-DC converter is controlled based on the detection result and the instruction of the system control circuit 50, and the necessary voltage is recorded for a necessary period. To each part including

  Reference numeral 82 denotes a connector, 84 denotes a connector, 86 denotes a primary battery such as an alkaline battery or lithium battery, a secondary battery such as a NiCd battery, NiMH battery, or Li-ion battery, an AC adapter, or the like.

  Reference numeral 90 denotes an interface with a recording medium such as a memory card or hard disk, and reference numeral 92 denotes a connector for connecting to a recording medium such as a memory card or hard disk. The interface and the connector may be configured using a PCMCIA card, a CF (Compact Flash (registered trademark)) card, or the like based on a standard.

  Further, when the interface 90 and the connector 92 are configured using a PCMCIA card, a CF (Compact Flash (registered trademark)) card, or the like, a LAN card, a modem card, a USB card, an IEEE 1394 card, a P1284 card, etc. By connecting various communication cards such as a SCSI card and a PHS, image data and management information attached to the image data can be transmitted to and from other computers and peripheral devices such as a printer.

  A protection unit 102 is a barrier that prevents the imaging unit from being soiled or damaged by covering the imaging unit including the photographing lens 10 of the digital camera 100.

  Reference numeral 104 denotes an optical viewfinder, which can perform photographing using only the optical viewfinder without using the electronic viewfinder function of the image display unit 28. In the optical viewfinder 104, some functions of the display unit 54, for example, a focus display, a camera shake warning display, a flash charge display, a shutter speed display, an aperture value display, an exposure correction display, and the like are installed.

  A communication unit 110 has various communication functions such as RS232C, USB, IEEE1394, P1284, SCSI, modem, LAN, and wireless communication. Image transmission can be performed by using this communication unit.

  Reference numeral 112 denotes a connector for connecting the digital camera 100 to another device by the communication unit 110 or an antenna in the case of wireless communication.

  Reference numeral 200 denotes a recording medium such as a memory card or a hard disk.

  The recording medium 200 includes a recording unit 202 composed of a semiconductor memory, a magnetic disk, or the like, an interface 204 with the digital camera 100, and a connector 206 for connecting with the digital camera 100.

  A watermark information embedding unit 94 embeds digital watermark data in image data.

  Reference numeral 95 denotes a dust position detection unit. By inputting image data, the position, size, and darkness of dust with respect to the image are detected. When dust is detected by the dust position detection unit 95, image data obtained by photographing a subject having a substantially uniform brightness, such as a white wall, where dust is conspicuous is input. A pixel having a luminance lower than a predetermined luminance is detected from the image data, and the pixel is determined as a dust pixel.

  Reference numeral 96 denotes a face position detection unit. By inputting image data, the position of the face, its size, the position of the eyes, and its size with respect to the image are detected. Various techniques are known for detecting a face from an image. For example, there is a method using learning represented by a neural network. In addition, there is a technique for identifying parts having physical shape features such as eyes, nose, mouth, and facial contour from image data using template matching. In addition, there is a technique that detects a feature amount of image data such as skin color or eye shape and uses statistical analysis (for example, Japanese Patent Laid-Open Nos. 10-232934 and 2000-48184). reference). The face position detection unit 96 detects the face position, its size, the eye position, and its size by any one of these methods.

  Reference numeral 97 denotes a watermark information embedding position determination unit that determines a position in which digital watermark information is embedded based on position information of an area predicted to be corrected later by image processing.

  In the digital camera 100, it is assumed that a photographer's name, copyright information, and the like are stored in advance in the nonvolatile memory 56 as data embedded in an image as a digital watermark. In addition, data to be embedded as a digital watermark may include shooting time information, GPS information, and the like. The data to be embedded as the electronic watermark is created by a personal computer, transmitted to the digital camera 100 via the interface 90 and the communication unit 110, and then stored in the nonvolatile memory 56.

  Next, the dust detection operation in the digital camera 100 will be described.

  First, the photographing mode is selected using the operation member 70, and the dust position acquisition photographing for obtaining the dust position attached to the surface of the optical element 14a disposed in front of the image sensor 14 is selected.

  FIG. 2 shows a menu for selecting a shooting mode. The menu is displayed on the display unit 54, the item is moved by the menu item moving button, and the shooting mode is selected by pressing the set button. This menu shows that normal shooting and dust position acquisition shooting can be selected. It should be noted that in this dust position acquisition shooting, a subject having a substantially uniform brightness, such as a white wall, is shot.

  FIG. 3 is a flowchart showing a sequence for performing dust position acquisition photographing.

  When dust position acquisition shooting is selected, the digital camera enters a dust position acquisition shooting mode. When a shutter button (not shown) is pressed (step S101), the digital camera operates the shutter 12 having an aperture function to perform shooting with the aperture stopped (step S102). The reason for shooting with the shutter aperture is to clearly capture the dust. The image data captured by the image sensor 14 is converted into digital data by the A / D converter 16 (step S103) and temporarily stored in the memory 30 (step S104). The image data temporarily stored in the memory 30 is input to the dust position detection unit 95, and the dust position is calculated (step S105). In the operation of calculating the dust position, the luminance value of each pixel in the image data is compared with a predetermined threshold value, and a pixel darker than the threshold value is determined as a pixel in which dust is reflected. Then, the position and size of the dust on the screen are calculated from the position of the pixel in which the dust is reflected.

  The calculated dust position data is data having information such as dust size and dust density in addition to position information. As shown in FIG. 4, the position information is expressed in absolute coordinates with the upper left corner of the image as the origin. As another way of holding the position information, it may be expressed by a difference from the position of the previous dust. The size information expresses the size necessary for correcting dust, and is set to a size (circle region having a radius R) that hides the entire dust as shown in FIG. The darkness information is expressed in a plurality of stages. These pieces of information are calculated for a plurality of detected dusts and are collected as information. FIG. 6 shows the collected dust position detection data. The dust position detection data thus obtained is stored in the nonvolatile memory 56 by the system control circuit 50 (step S106). Note that the unit of numerical values of coordinates and radius in FIG. 6 is a pixel, and the unit of darkness is a stage of luminance value.

  Next, using the operation member 70, information embedding by digital watermark is selected. FIG. 7 shows a menu for selecting information embedding. The menu is displayed on the display unit 54, the item is moved by the menu item moving button, and information embedding is selected by pressing the set button. In this menu, it is shown that the case where information is embedded or not can be selected.

  FIG. 8 is a flowchart for recording digital watermark information in image data obtained by imaging and storing the image data.

  When a shutter button (not shown) is pressed (step S201), the digital camera 100 captures a normal image that is not a dust detection image (step S202). Image data captured by the image sensor 14 is converted into digital data by the A / D converter 16 (step S203) and temporarily stored in the memory 30 (step S204). Next, dust position detection data stored in advance is read from the nonvolatile memory 56 and input to the watermark information embedding position determination unit 97. At the same time, in addition to dust position detection data, the lens aperture state at the time of shooting a normal image is input. This is because the reflection position of the digital watermark information is changed according to the state of the diaphragm at the time of photographing because the reflection of dust in the image data changes depending on the state of the diaphragm. Using the dust position detection data and the aperture value, the watermark information embedding position determining unit 97 determines the embedding position of the digital watermark information (step S205). The image data primarily stored in the memory 30 is read into the watermark information embedding unit 94, and the digital watermark information is embedded in the position determined in step S205 with respect to the normal photographed image data and stored in the memory 30 (step S206). ). Then, the image data in which the digital watermark information is embedded is read from the memory 30, and the image is compressed by the compression / decompression circuit 32 (step S207) and stored in the recording medium 200 (step S208).

  FIG. 9 is a flowchart showing a method for the watermark information embedding position determination unit 97 to select dust information to be excluded from positions where electronic watermark information is embedded using the aperture value.

  First, the aperture value at the time of shooting an image to be embedded with the digital watermark is input to the watermark information embedding position determining unit 97 (step S301). If the image was taken with a large aperture value at the time of shooting, the dust attached to the optical element 14a was clearly reflected, and if the image was shot with a small aperture value close to the full aperture, large dust Only is reflected. Therefore, the input aperture value is compared with a predetermined threshold value (step S302). If the aperture value is smaller than the threshold value (the aperture is open), the amount of dust reflected is reduced, and it is determined that only large dust is excluded from the watermark embedding position (step S303). In other words, the digital watermark is not embedded at a position where large dust exists. If the aperture value is larger than the threshold (the aperture is narrowed down), even small dust is reflected, so that it is determined to include even the smallest dust positions to be excluded (step S304). That is, an electronic watermark is not embedded at a position where not only large dust but also small dust exists.

  In the above-described embodiment, when the watermark information embedding position determination unit 97 selects dust information to be excluded from the digital watermark information embedding position using the aperture value, the threshold information is set using one threshold value. The radius was determined. However, the present invention is not limited to this, and the radius of dust to be excluded may be determined using a plurality of threshold values.

  In addition, the color density may be taken into consideration instead of the radius of dust to be excluded. Since darker dust is more conspicuous, when the aperture value at the time of shooting is small, the position of dark dust is excluded from the watermark information embedding position, and when the aperture value of shooting is large, the watermark information up to the lighter dust position You may make it exclude from an embedding position.

  Further, the spatial frequency component around the dust position may be taken into consideration. If the surrounding spatial frequency component is low, the image is monotonous and dust tends to stand out.Therefore, the location of the dust is excluded from the watermark information embedding position, and if the surrounding spatial frequency component is high, the image is complicated and the dust stands out. Since it is difficult, the position of the dust may not be excluded from the watermark information embedding position.

  Further, the pupil position of the lens may be used instead of the aperture value. Since the area where dust is reflected changes depending on the pupil position of the lens, the correction area where dust should be corrected can be determined by using the pupil position information, and the correction area where dust should be corrected can be determined by removing the correction area. The information embedding position by the watermark can be determined.

  As described above, according to the above-described embodiment, the digital watermark is embedded in a portion other than the portion that may be corrected as a region in which the shadow of the foreign object is reflected in the image processing after shooting. It is possible to prevent the digital watermark information from being lost.

(Other embodiments)
The object of the above embodiment can also be achieved by the following method. That is, a storage medium (or recording medium) in which a program code of software that realizes the functions of the above-described embodiments is recorded is supplied to the system or apparatus. Then, the computer (or CPU or MPU) of the system or apparatus reads and executes the program code stored in the storage medium. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention. Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but the present invention includes the following cases. That is, based on the instruction of the program code, an operating system (OS) running on the computer performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

  Furthermore, the following cases are also included in the present invention. That is, the program code read from the storage medium is written in a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer. Thereafter, based on the instruction of the program code, the CPU or the like provided in the function expansion card or function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

  When the present invention is applied to the above storage medium, the storage medium stores program codes corresponding to the procedure described above.

It is a figure which shows the structure of the digital camera as an imaging device in one Embodiment of this invention. It is a figure which shows the example of a display of a photography mode selection menu. It is a flowchart which shows operation | movement of dust position acquisition imaging | photography. It is a figure explaining dust position information. It is a figure explaining dust position information. It is a figure which shows the example of the collected dust position information. It is a figure which shows the example of a display of the menu which selects information embedding. It is a flowchart which shows the operation | movement which embeds digital watermark information in the imaged image data. It is a flowchart explaining the operation | movement of a watermark information embedding position determination part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Shooting lens 12 Shutter 14 Image pick-up element 16 A / D converter 18 Timing generation circuit 20 Image processing circuit 22 Memory control circuit 24 Image display memory 26 D / A converter 28 Image display part 30 Memory 32 Image compression / decompression circuit 40 Exposure Control unit 42 Distance control unit 44 Zoom control unit 46 Barrier control unit 48 Flash 50 System control circuit 52 Memory 54 Display unit 56 Non-volatile memory 60 Mode dial switch 62 Shutter switch SW1
64 Shutter switch SW2
66 Image display ON / OFF switch 68 Quick review ON / OFF switch 70 Operation unit 80 Power supply control unit 82 Connector 84 Connector 86 Power supply unit 90 Interface 92 Connector 94 Watermark information embedding unit 95 Dust position detection unit 96 Face position detection unit 97 Watermark information Embedding position determination unit 98 Recording medium attachment / detachment detection unit 100 Digital camera 102 Protection unit 104 Optical viewfinder 110 Communication unit 112 Connector (or antenna)
200 Recording Medium 202 Recording Unit 204 Interface 206 Connector

Claims (6)

Imaging means for photoelectrically converting a subject image to generate an image signal;
Of the image signal generated by the imaging unit, a region that may be corrected as a region in which a shadow of a foreign object attached to an optical element disposed in front of the imaging unit is reflected by subsequent image processing Detecting means for detecting a correction area,
Watermark information embedding means for embedding digital watermark information in the image signal;
Control means for controlling the watermark information embedding means so as to embed the digital watermark information in the image signal by excluding the correction area detected by the detection means from the area to be embedded with the digital watermark information;
An imaging apparatus comprising:   The imaging apparatus according to claim 1, wherein the detection unit detects the correction area based on a shadow size of the foreign matter.   The imaging apparatus according to claim 1, wherein the detection unit detects the correction area based on a shadow density of the foreign matter.   The imaging apparatus according to claim 1, wherein the detection unit detects the correction area based on a spatial frequency of a subject around the shadow of the foreign object. An imaging unit that photoelectrically converts a subject image to generate an image signal, and a foreign object attached to an optical element disposed in front of the imaging unit by subsequent image processing of the image signal generated by the imaging unit A method for controlling an imaging apparatus comprising: a detection unit that detects a correction region that is a region that may be corrected as a region in which a shadow of the image is reflected; and a watermark information embedding unit that embeds digital watermark information in the image signal Because
A control step of controlling the watermark information embedding unit so as to embed the digital watermark information in the image signal by excluding the correction region detected by the detection unit from the region to be embedded with the digital watermark information. A control method for an imaging apparatus.   A program for causing a computer to execute the control method according to claim 5.

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