JP2008011264A - Imaging apparatus, its control method, program, and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a hit rate when a main subject is automatically selected from a picture. <P>SOLUTION: An imaging apparatus comprises an imaging element which photoelectrically converts a subject image, a face detector which detects the face of a person being a subject from an image signal obtained by the imaging element, a photographic mode setting unit which sets a photographic mode, and a main subject discriminating unit which discriminates the main subject from the face of the person detected by the face detector and changes standards for discriminating the main subject from the face of the person detected by the face detector according to the photographic mode set by the photographic mode setting unit. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for selecting a main subject from a screen when capturing a still image or a moving image.

  2. Description of the Related Art Conventionally, an imaging apparatus that automatically determines a main subject in order to adjust the focus and exposure to the main subject is known. As a technique for automatically discriminating a main subject as described above, a technique using face recognition has been proposed.

  For example, Patent Document 1 proposes a camera that focuses on a person determined to be a main subject when a plurality of persons are detected. As a criterion for determining the main subject, a short distance, a large face area, close to the center of the screen, and the like are adopted.

Patent Document 2 proposes a digital camera that can select feature parts in a predetermined order according to an instruction from a user. In this technique, it is possible to select a plurality of faces existing on the screen in the order of closeness or descending order by a user operation.
JP 2002-512255 A JP 2004-320287 A

  Conventionally, as described above, it has a function of detecting a face on the screen and discriminating a face having a short distance or a large face as a main subject. This is because a close face or a large face is highly likely to be a main subject.

  However, a close face or a large face is not always the main subject. In particular, when photographing a child, a subject with a small face becomes the main subject. If a subject with a large face is always selected as the main subject, the child cannot be selected as the main subject when an adult and a child are included in the screen. In a shooting mode for shooting a child (hereinafter referred to as a “kids mode”), it is a big problem that the child cannot be selected as a main subject.

  Therefore, the present invention has been made in view of the above-described problems, and an object of the present invention is to improve the hit rate when the main subject is automatically selected from the screen.

  In order to solve the above-described problems and achieve the object, an imaging apparatus according to the present invention includes an imaging device that photoelectrically converts a subject image, and an image signal obtained by the imaging device that identifies a human face that is a subject. A face detection unit for detection, a shooting mode setting unit for setting a shooting mode, a main subject is determined from the face of the person detected by the face detection unit, and the main object is determined according to the shooting mode set by the shooting mode setting unit. And a main subject determining means for changing a reference for determining a main subject from the face of the person detected by the face detecting means.

  The image pickup apparatus control method according to the present invention is a method for controlling an image pickup apparatus including an image pickup device that performs photoelectric conversion on a subject image, and is based on an image signal obtained by the image pickup device. A face detection step for detecting the image, a shooting mode setting step for setting a shooting mode, a main subject from the face of the person detected in the face detection step, and a shooting mode set in the shooting mode setting step. And a main subject determination step of changing a reference for determining a main subject from the face of the person detected in the face detection step.

  A program according to the present invention causes a computer to execute the above control method.

  A storage medium according to the present invention stores the above program.

  According to the present invention, it is possible to improve the hit rate when the main subject is automatically selected from the screen.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a diagram showing a block configuration of a digital camera which is a first embodiment of the imaging apparatus of the present invention.

  In FIG. 1, reference numeral 100 denotes a digital camera.

  Reference numeral 10 denotes a photographing lens, and reference numeral 12 denotes a shutter having an aperture function.

  An image sensor 14 converts an optical image into an electrical signal, and an A / D converter 16 converts an analog output signal of the image sensor 14 into a digital signal.

  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. I do. As a 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.

  The data of the A / D converter 16 is written into the image display memory 24 or the memory 30 via the image processing circuit 20 and the memory control circuit 22 or the data of the A / D converter 16 is directly passed through the memory control circuit 22. It is.

  Reference numeral 24 denotes an image display memory, 26 denotes a D / A converter, 28 denotes an image display unit composed of a TFT, an LCD, and the like. Display image data written in the image display memory 24 passes through the D / A converter 26. Are 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 is installed in a single or a plurality of positions near the operation unit of the digital camera 100 so as to be visually recognized, and is configured by, for example, a combination of an LCD, an LED, a sound generation element, and the like.

  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 is, for example, single shot / continuous shooting display, self-timer display, compression rate display, recording pixel number display, recording number display, remaining image number display There is. There are also shutter speed display, aperture value display, exposure compensation display, flash display, red-eye reduction display, macro shooting display, buzzer setting display, clock battery level display, battery level display, and error display. In addition, there are information display with a multi-digit number, attachment / detachment state display of the recording media 200 and 210, communication I / F operation display, date / time display, display showing the connection state with an external computer, and the like.

  Among the display contents of the display unit 54, the following are displayed in the optical viewfinder 104. For example, in-focus display, shooting preparation completion display, camera shake warning display, flash charge display, flash charge completion display, shutter speed display, aperture value display, exposure correction display, recording medium writing operation display, and the like.

  Furthermore, among the display contents of the display unit 54, the following are displayed on the LED or the like. For example, in-focus display, shooting preparation completion display, camera shake warning display, flash charge display, flash charge completion display, recording medium writing operation display, macro shooting setting notification display, secondary battery charge state display, and the like.

  And what is displayed on a lamp etc. among the display contents of the display part 54 includes a self-timer notification lamp, for example. This self-timer notification lamp may be used in common with AF auxiliary light.

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

  Reference numerals 60, 62, 64, 66, and 70 are operation units for inputting various operation instructions of the system control circuit 50. One or a plurality of operation units such as a switch, a dial, a touch panel, pointing by line-of-sight detection, a voice recognition device, and the like. Composed of a combination.

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

  Reference numeral 60 denotes a mode dial switch which can be switched between an automatic shooting mode, a program shooting mode, a shutter speed priority shooting mode, an aperture priority shooting mode, and a manual shooting mode. Furthermore, it is possible to switch and set various shooting modes such as a depth of focus priority (depth) shooting mode, a portrait shooting mode, a landscape shooting mode, a close-up shooting mode, a sports shooting mode, a night view shooting mode, and a panoramic shooting mode.

  Reference numeral 62 denotes a shutter switch SW1, which is turned on when a shutter button (not shown) is being operated (half-pressed), and performs AF (autofocus) processing, AE (automatic exposure) processing, AWB (auto white balance) processing, and EF (flash pre-flash). ) Instruct the start of operations such as processing.

  Reference numeral 64 denotes a shutter switch SW2, which is turned on when a shutter button (not shown) has been operated (fully pressed), and instructs the start of a series of processes including exposure processing, development processing, and recording processing. The exposure process is a process of 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. The development process is a process for making the image data visible by using an operation in the image processing circuit 20 or the memory control circuit 22. The recording process is a process of reading image data from the memory 30, compressing it by the compression / decompression circuit 32, and writing it to the recording medium 200 or 210.

  Reference numeral 66 denotes a playback mode switch which can set various function modes such as a playback mode, a multi-screen playback / erase mode, and a PC (personal computer) connection mode.

  Reference numeral 68 denotes an attitude mode switch. The attitude of the digital camera 100 is detected by the camera attitude detection unit 106, and the detected camera attitude is recorded on the recording medium as an image attitude flag together with an image of the detected camera attitude at the time of shooting. To do. At the time of reproduction, ON / OFF of an attitude mode for performing an operation of switching an image display method according to the read image attitude flag is set.

  An operation unit 70 includes various buttons, a touch panel, and the like, and includes 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, and the like. Menu move + (plus) button, menu move-(minus) button, playback image move + (plus) button, playback image move-(minus) button, shooting image quality selection button, exposure compensation button, date / time setting button Etc. are also included. In addition, a selection / switch button for setting selection and switching of various functions when performing shooting and playback in panorama mode and the like, and a determination for setting and executing various functions when performing shooting and playback in panorama mode and the like. / Execute button etc. are also included. Further, an image display ON / OFF switch for setting ON / OFF of the image display unit 28 and a quick review ON / OFF switch for setting a quick review function for automatically reproducing image data taken immediately after photographing are also included. Further, a compression mode switch that is a switch for selecting a compression rate of JPEG compression or for selecting a CCD RAW mode in which a signal of an image sensor is directly digitized and recorded on a recording medium is also included.

  Reference numeral 72 denotes a power switch, which can be switched between power-on and power-off modes.

  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, and 86 denotes a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, NiMH battery, or Li ion battery, an AC adapter, or the like.

  Reference numerals 90 and 94 denote interfaces with recording media such as memory cards and hard disks, and reference numerals 92 and 96 denote connectors for connecting to recording media such as memory cards and hard disks. Reference numeral 98 denotes a recording medium attachment / detachment detection unit that detects whether or not the recording medium 200 or 210 is attached to the connectors 92 and / or 96.

  In the present embodiment, it is assumed that there are two systems of interfaces and connectors for attaching a recording medium. Of course, the interface and the connector for attaching the recording medium may have a single or a plurality of systems and any number of systems. Moreover, it is good also as a structure provided with combining the interface and connector of a different standard.

  The interface and connector may be configured using a PCMCIA card, a CF (Compact Flash (registered trademark)) card, or the like that conforms to a standard.

  Furthermore, when the interfaces 90 and 94 and the connectors 92 and 96 are configured using a PCMCIA card, a CF card or the like that conforms to the standard, the following is possible. That is, various communication cards such as a LAN card, a modem card, a USB card, an IEEE 1394 card, a P1284 card, a SCSI card, and a communication card such as a PHS are connected. Thereby, image data and management information attached to the image data can be transferred to and from other computers and peripheral devices such as a printer.

  Reference numeral 104 denotes an optical viewfinder, which can take an image 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.

  Reference numeral 106 denotes a camera posture detection unit, which can detect either the horizontal position shooting or the vertical position shooting by detecting the posture of the digital camera 100.

  A communication unit 110 has various communication functions such as RS232C, USB, IEEE1394, P1284, SCSI, modem, LAN, and wireless communication.

  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.

  Reference numeral 210 denotes a recording medium such as a memory card or a hard disk.

  The recording medium 210 includes a recording unit 212 composed of a semiconductor memory, a magnetic disk, and the like, an interface 214 with the digital camera 100, and a connector 216 for connecting with the digital camera 100.

  Next, FIGS. 2 and 3 are flowcharts of the main routine of the digital camera 100 according to the first embodiment.

  The operation of the digital camera 100 will be described with reference to FIGS.

  Upon power-on such as battery replacement, the system control circuit 50 initializes flags, control variables, and the like (step S101), and initializes the image display of the image display unit 28 to an OFF state (step S102).

  The system control circuit 50 determines the set position of the power switch 72. If the power switch 72 is set to power OFF (step S103), the system control circuit 50 executes an end process (step S104), and then returns to step S103. In the termination process, the display of each display unit is changed to a termination state, the barrier of the protection unit is closed to protect the imaging unit, and necessary parameters, setting values, and setting modes including flags and control variables are set in the nonvolatile memory 56. To record. Further, an unnecessary power source of each part of the digital camera 100 including the image display unit 28 is shut off by the power source control unit 80.

  If the power switch 72 is set to ON (step S103), the system control circuit 50 determines the setting position of the mode dial 60, and if the mode dial 60 is set to the shooting mode (step S105). The process proceeds to step S107.

  If the mode dial 60 has been set to another mode (step S105), the system control circuit 50 executes processing corresponding to the selected mode (step S106), and returns to step S103 when the processing is completed. .

  The system control circuit 50 determines whether or not there is a problem with the operation of the digital camera 100 in terms of the remaining capacity and operation status of the power source 86 configured by a battery or the like by the power source control unit 80 (step S107). If there is a problem, the display unit 54 is used to display a predetermined warning by image or sound (step S109), and then the process returns to step S103.

  If there is no problem with the power supply 86 (step S107), the system control circuit 50 determines whether or not the recording medium 200 or 210 is loaded, and acquires management information for image data recorded on the recording medium 200 or 210. Do. Then, it is determined whether or not the operation state of the recording medium 200 or 210 has a problem in the operation of the digital camera 100, particularly the recording / reproducing operation of the image data with respect to the recording medium (step S108). If there is a problem with the recording medium, the display unit 54 is used to display a predetermined warning by image or sound (step S109), and then the process returns to step S103. If there is no problem in the recording medium, the process proceeds to step S110.

  In step S108, the system control circuit 50 also acquires the final shooting number Nmax of the image data recorded on the recording medium 200 or 210.

  The final shooting number Nmax is read from the recording medium 200 or 210 via the connector 92 or 96 and the interface 90 or 94 and stored in the internal memory or the memory 52 of the system control circuit 50.

  In step S <b> 110, the system control circuit 50 displays various setting states of the digital camera 100 using images and sounds using the display unit 54. If the image display of the image display unit 28 is ON, the image display unit 28 is also used to display various setting states of the digital camera 100 using images and sounds.

  Next, the process proceeds to step S121 in FIG. 3, and if the shutter switch SW1 is not pressed, the process returns to step S103.

  If the shutter switch SW1 is pressed (step S121), the process proceeds to step S122.

  The system control circuit 50 performs a distance measurement process to focus the photographing lens 10 on the subject, performs a photometry process, and determines an aperture value and a shutter time (step S122). In the photometric process, the flash is set if necessary.

  Details of the distance measurement / photometry processing step S122 will be described later with reference to FIG.

  If the distance measurement / photometry processing step S122 is completed and the shutter switch SW2 is not pressed (step S123) and the shutter switch SW1 is also released (step S124), the process returns to step S103.

  If the shutter switch SW2 is pressed (step S123), the process proceeds to step S125.

  In preparation for shooting, the system control circuit 50 manages files and folders, such as determining a storage file name and creating a new folder (step S125).

  The system control circuit 50 executes photographing processing including exposure processing and development processing (step S126). In the exposure process, an image taken in the memory 30 via the image sensor 14, the A / D converter 16, the image processing circuit 20, the memory control circuit 22, or directly from the A / D converter via the memory control circuit 22. This is a process of writing data. The development process is a process of reading the image data written in the memory 30 and converting the image data into visible image data by using the memory control circuit 22 and, if necessary, the image processing circuit 20.

  Details of the photographing processing step S126 will be described later with reference to FIG.

  When the photographing process step S126 is completed, a quick review display is performed (step S127). The quick review display is an operation for displaying a photographed image on the image display unit 28 for a predetermined time immediately after photographing.

  When the quick review display step S127 is completed, the system control circuit 50 reads the captured image data written in the memory 30, and performs various image processing using the memory control circuit 22 and, if necessary, the image processing circuit 20. Do. In addition, image compression processing corresponding to the mode set using the compression / decompression circuit 32 is performed. Thereafter, a recording process for writing image data to the recording medium 200 or 210 is executed via the interface 90 or 94 and the connector 92 or 96 (step S128).

  When the image display unit 28 is ON, a display such as “BUSY” that clearly indicates that the writing operation is being performed while the image data is being written to the recording medium 200 or 210 is displayed on the image display unit 28. To do.

  Further, the display unit 54 also displays a recording medium writing operation display such as blinking the LED.

  When the recording process is finished (step S128), the process returns to step S103.

  FIG. 4 is a detailed flowchart showing the distance measurement / photometry processing in step S122 of FIG.

  First, in step S201, the system control circuit 50 reads out a charge signal from the image sensor 14 and reads captured image data into the image processing circuit 20 via the A / D converter 16 (step S201). Using the sequentially read image data, the image processing circuit 20 is a predetermined used for TTL (through-the-lens) AE (automatic exposure) processing, EF (flash pre-flash) processing, and AF (autofocus) processing. The operation is performed.

  In each processing here, a specific portion of the total number of photographed pixels is extracted by extracting a necessary portion according to necessity and used for calculation. As a result, in each of the TTL method AE, EF, AWB, and AF processes, it is possible to perform an optimal calculation for each different mode such as the center weight mode, the average mode, and the evaluation mode.

  Using this read image data, the image processing circuit 20 performs face recognition processing (processing for detecting a face in the image) (step S202).

  It should be noted that various techniques are known as techniques for detecting a face performed by the image processing circuit 20. 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). In the present embodiment, face identification processing is performed by detecting a pair of eyes (both eyes), nose, mouth, and face outline, and determining a person's face from their relative positions.

  Next, in step S203, the number of faces recognized in step S202 is stored in a variable FaceNum in the internal memory of the system control circuit 50 or the memory 52.

  The system control circuit 50 sets an AF area (step S204). This is a process for setting which face of a plurality of faces recognized from the image data is to be focused. Details of the AF area setting process will be described later with reference to FIG.

  Using the calculation result in the image processing circuit 20, the system control circuit 50 determines whether or not the exposure is appropriate (step S205).

  If the exposure is not appropriate (step S205), the system control circuit 50 performs AE control using the exposure control unit 40 (step S206), and proceeds to step S207.

  Using the measurement data obtained by the AE control, the system control circuit 50 determines whether or not the flash is necessary (step S207). If the flash is necessary, the flash flag is set and the flash is charged (step S209). ) Proceed to step S208.

  If no flash is required (step S207), the process proceeds to step S208.

  In step S208, the system control circuit 50 reads the charge signal from the image sensor 14, reads the captured image data into the image processing circuit 20 via the A / D converter 16, and returns to step S205.

  If it is determined in step S205 that the exposure is appropriate, the measurement data and / or setting parameters are stored in the internal memory of the system control circuit 50 or the memory 52.

  Using the calculation result in the image processing circuit 20 and the measurement data obtained by the AE control, the system control circuit 50 uses the image processing circuit 20 until the white balance (AWB) is determined to be appropriate (step S210). AWB control is performed (step S211).

  If it is determined that the white balance (AWB) is appropriate (step S210), the measurement data and / or setting parameters are stored in the internal memory or the memory 52 of the system control circuit 50.

  Using the measurement data obtained by the AE control and the AWB control, the system control circuit 50 performs the AF control using the distance measurement control unit 42 until the distance measurement (AF) is determined to be in focus (step S212). (Step S213).

  If it is determined that the distance measurement (AF) is in focus (step S212), the measurement data and / or setting parameters are stored in the internal memory or the memory 52 of the system control circuit 50, and the distance measurement / photometry processing routine (step of FIG. 3). S122) is terminated.

  FIG. 5 is a detailed flowchart showing the photographing process in step S126 of FIG.

  First, in steps S301 and S302, the system control circuit 50 opens the shutter 12 having an aperture function according to the aperture value by the exposure control unit 40 in accordance with the photometric data stored in the internal memory or the memory 52. The image sensor 14 is exposed.

  It is determined whether or not the flash 48 is necessary based on the flash flag (step S303), and if necessary, the flash is emitted (step S304).

  The system control circuit 50 waits for the end of exposure of the image sensor 14 according to the photometric data (step S305), closes the shutter 12 (step S306), and reads out the charge signal from the image sensor 14. Then, the data of the photographed image is written in the memory 30 via the A / D converter 16, the image processing circuit 20, the memory control circuit 22, or directly from the A / D converter 16 via the memory control circuit 22 (step). S307).

  When the series of processing is finished, the photographing processing routine (step S126 in FIG. 3) is finished.

  FIG. 6 is a detailed flowchart showing the AF area setting process in step S204 of FIG.

  First, the system control circuit 50 determines the AF area selection mode stored in the nonvolatile memory 56 or the like (step S1001). If the AF area is set to be arbitrarily selectable by the user, the area set by the user is set as the AF area (step S1002), and the AF area setting processing routine (step S204 in FIG. 4) is terminated. To do.

  When the AF area is automatically set (step S1001), it is determined whether the variable FaceNum in the internal memory of the system control circuit 50 or the memory 52 is 1 or more (step S1003). The variable FaceNum is the number of faces detected as a result of the face recognition process in step S202 of FIG. 4, and is set in step S203.

  When the variable FaceNum is 0 (step S1003), normal AF area setting is performed without using the result of the face recognition process (step S1004). An AF area is set by central one-point AF, AiAF (automatic selection from a plurality of AF frames), or the like. After setting the AF area (step S1004), the AF area setting processing routine (step S204 in FIG. 4) is terminated.

  When the variable FaceNum in the internal memory of the system control circuit 50 or the memory 52 is 1 or more (step S1003), the following processing is performed. That is, the system control circuit 50 determines the current shooting mode from the setting position of the mode dial 60, the value of a variable in the internal memory of the system control circuit 50 or the memory 52, and the like (step S1005).

  If the shooting mode is other than the kids mode (a mode for shooting a child beautifully) (step S1005), the process proceeds to step S1006. Then, the system control circuit 50 determines the largest face among the FaceNum faces detected in the face detection processing step S202 (step S1006). Then, the process proceeds to step S1007. The size of the face in this case is the size of the face on the image sensor (the size of the face projected on the image sensor), and the face size increases as the distance becomes shorter. Therefore, an effect similar to the process of determining a face at a short distance can be expected.

  The system control circuit 50 sets the AF area corresponding to the face having the largest size on the image sensor determined in step S1006 as the AF area to be adopted (step S1007), and the AF area setting processing routine (step S204 in FIG. 4). ) Ends.

  When the shooting mode is the kids mode (step S1005), the system control circuit 50 acquires distance information to each FaceNum face detected in step S202 of FIG. 4 (step S1008). Then, the actual face size (actual face size of the person who is the subject) is calculated from the obtained distance information and the face size on the image sensor (step S1009).

  After calculating the actual sizes of all the faces detected in step S202 (step S1009), the system control circuit 50 determines the face with the smallest actual size (step S1010). Then, the AF area corresponding to the face having the smallest actual size is set as the AF area to be adopted (step S1011).

  In steps S1008 to S1011, the purpose is not to select the closest face but to select the face of a child. Therefore, the actual face size is obtained in consideration of distance information, and the actual size is small. Select a face.

  After setting the AF area corresponding to the face having the smallest actual size as the AF area to be adopted (step S1011), the AF area setting processing routine (step S204 in FIG. 4) is ended.

  As described above, in this embodiment, a subject with a large face and a subject at a short distance are selected as main subjects in the mode other than the kids mode, and a subject with the smallest actual face size is selected as the main subject in the kids mode. . Therefore, even when an adult and a child coexist on the screen, the child can be selected in the kids mode. In other words, it is possible to focus on the face of the child, which is the main subject, or to adjust the exposure.

(Second Embodiment)
The operation of the second embodiment of the present invention will be described with reference to FIGS. 2 to 5 and FIG.

  The configuration of the digital camera of the second embodiment is the same as that of the first embodiment shown in FIG.

  The flowcharts of the main routine of the digital camera 100 of the second embodiment are as shown in FIGS. 2 and 3, and are the same as described in the first embodiment.

  A detailed flowchart of the distance measurement / photometry processing in step S122 of FIG. 3 is as shown in FIG. 4 and as described in the first embodiment.

  A detailed flowchart of the photographing process in step S126 of FIG. 3 is as shown in FIG. 5, as described in the first embodiment.

  FIG. 7 is a detailed flowchart of the AF area setting process in step S204 of FIG. 4 in the second embodiment.

  The system control circuit 50 determines the AF area selection mode stored in the nonvolatile memory 56 or the like (step S1101). If the AF area is set to be arbitrarily selectable by the user, the area set by the user is set as the AF area (step S1102), and the AF area setting processing routine is terminated.

  When the AF area is automatically set (step S1101), it is determined whether the variable FaceNum in the internal memory of the system control circuit 50 or the memory 52 is 1 or more (step S1103). The variable FaceNum is the number of faces detected as a result of the face recognition process in step S202 of FIG. 4, and is set in step S203.

  If the variable FaceNum is 0, normal AF area setting is performed without using the result of the face recognition process (step S1104). An AF area is set by central one-point AF, AiAF (automatic selection from a plurality of AF frames), or the like. After setting the AF area (step S1104), the AF area setting processing routine is terminated.

  When the variable FaceNum in the internal memory of the system control circuit 50 or the memory 52 is 1 or more (step S1103), the following processing is performed. That is, the system control circuit 50 determines the current shooting mode from the setting position of the mode dial 60, the value of a variable in the internal memory of the system control circuit 50 or the memory 52, etc. (step S1105).

  When the shooting mode is other than the kids mode (step S1105), the system control circuit 50 determines the largest face among the FaceNum faces detected in the face detection process (step S202 in FIG. 4) (step S1106). ), And proceeds to step S1107.

  In this case, the size of the face is the size of the face on the image sensor, and the size of the face increases as the distance decreases. Therefore, an effect similar to the process of determining a face at a short distance can be expected.

  The system control circuit 50 sets the AF area corresponding to the face having the largest size on the image sensor determined in step S1106 as the AF area to be adopted (step S1107), and ends the AF area setting processing routine.

  If the shooting mode is the kids mode (step S1105), the system control circuit 50 acquires distance information to each FaceNum face detected in step S202 (step S1108). Then, the actual face size (actual face size of the person who is the subject) is calculated from the obtained distance information and the face size on the image sensor (step S1109).

  After calculating the actual sizes of all the faces detected in step S202 (step S1109), the FaceNum faces are classified into a child face and other faces (step S1110). For classification, for example, faces whose actual size is a predetermined value or less may be grouped as child faces.

  When the child face group is created (step S1110), the face closest to the child face group is determined (step S1111), and the AF area corresponding to the determined child face closest to the AF is adopted. The area is set (step S1112). In step S1111, the distance information acquired in step S1108 may be used. Alternatively, the largest child face may be selected instead of the distance.

  When step S1112 is completed, the AF area setting processing routine is ended.

  As described above, in the present embodiment, a subject with a large face and a subject at a short distance are selected as main subjects except in the kids mode. The closest face is selected as the main subject. Therefore, even when an adult and a child coexist on the screen, it is possible to select a child in the kids mode, and even when there are multiple children, a short distance or a large face (image pickup device) that is likely to be a main subject. Top size) Children can be selected.

  In the above embodiment, the following can be used as the recording media 200 and 210. That is, not only a memory card such as a PCMCIA card or compact flash (registered trademark), a hard disk, but also a micro DAT, a magneto-optical disk, an optical disk such as a CD-R or CD-RW, a phase change optical disk such as a DVD, etc. .

  Further, the recording media 200 and 210 may be a composite medium in which a memory card and a hard disk are integrated, or may be configured to be partly removable from the composite medium.

  In the above embodiment, the recording media 200 and 210 have been described as being separated from the digital camera 100 and arbitrarily connectable, but any or all of the recording media may be fixed to the digital camera 100. Good.

  Further, the digital camera 100 may be configured such that any one or a plurality of recording media 200 or 210 can be connected.

  In the above embodiment, the recording medium 200 and 210 are mounted on the digital camera 100. However, the recording medium may have a single or a plurality of combinations.

  Note that the present invention may be applied to a system composed of a plurality of devices or an apparatus composed of a single device.

  In the present invention, the above-described embodiments or the technical elements may be combined as necessary.

  Further, the present invention may be applied to all or a part of the structure of the claims or the embodiment to form one device or to be combined with another device. It may be an element constituting the apparatus.

(Other embodiments)
The object of each embodiment is also 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) or the like 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 into 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, a 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 block configuration of the digital camera of the 1st Embodiment of this invention. It is a flowchart of the main routine of the digital camera of 1st Embodiment. It is a flowchart of the main routine of the digital camera of 1st Embodiment. It is a flowchart of the distance measurement and photometry processing routine in the 1st Embodiment of this invention. It is a flowchart of the imaging | photography process routine in the 1st Embodiment of this invention. 4 is a flowchart of an AF area setting process routine according to the first embodiment of the present invention. 12 is a flowchart of an AF area setting process routine according to the second embodiment of the present invention.

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 circuit 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 playback mode switch 68 attitude mode switch 70 operation unit 72 power switch 80 power control unit 82 connector 84 connector 86 power source unit 90 interface 92 connector 94 interface 96 connector 98 recording medium attachment / detachment detection unit 100 image processing apparatus 102 barrier 104 optical viewfinder 106 camera Attitude detection unit 110 Communication unit 112 Connector (or antenna)
200 Recording Medium 202 Recording Unit 204 Interface 206 Connector 210 Recording Medium 212 Recording Unit 214 Interface 216 Connector

Claims (10)

An image sensor that photoelectrically converts a subject image;
Face detection means for detecting the face of a person as a subject from the image signal obtained by the image sensor;
A shooting mode setting means for setting a shooting mode;
The main subject is discriminated from the face of the person detected by the face detecting means, and the main subject is discriminated from the face of the person detected by the face detecting means according to the shooting mode set by the shooting mode setting means. A main subject discrimination means for changing a reference to be performed,
An imaging apparatus comprising:   The imaging apparatus according to claim 1, wherein the main subject determination unit determines a main subject based on a size of a face projected on the image sensor.   Based on the distance detection means for detecting the distance to the face detected by the face detection means, the distance to the face detected by the distance detection means, and the size of the face projected on the image sensor The imaging apparatus according to claim 1, further comprising a calculation unit that calculates a size of an actual face of the person.   The imaging apparatus according to claim 3, wherein the main subject determination unit determines a main subject based on an actual face size of the person calculated by the calculation unit.   5. The main subject determination unit determines a subject whose actual face of a person calculated by the calculation unit is the smallest or a subject that can be regarded as a child as a main subject. Imaging device.   The imaging apparatus according to claim 1, further comprising a focus detection unit configured to detect a focus of the subject image using a focus detection frame corresponding to a main subject determined by the main subject determination unit.   The imaging apparatus according to claim 1, wherein the shooting mode includes a child shooting mode. A method for controlling an imaging device including an imaging device that photoelectrically converts a subject image,
A face detection step of detecting a face of a person who is a subject from an image signal obtained by the imaging device;
A shooting mode setting process for setting a shooting mode;
The main subject is determined from the face of the person detected in the face detection step, and the main subject is determined from the face of the person detected in the face detection step according to the shooting mode set in the shooting mode setting step. A main subject discrimination process for changing a reference to be performed,
An image pickup apparatus control method comprising:   A program for causing a computer to execute the control method according to claim 8.   A computer-readable storage medium storing the program according to claim 9.

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