JP5828722B2 - Imaging apparatus, control method therefor, program, and storage medium - Google Patents

Description

  The present invention relates to light emission control in flash photography.

  In conventional cameras, photographing is performed using a light emitting means such as a strobe (xenon (Xe) tube) in order to brighten a dark subject. One of the features of a xenon tube is that it can instantaneously emit intense light (a large amount of light). On the other hand, a technique has also been proposed in which the amount of light emitted from the light emitting means is controlled so that the face of a subject is detected and the exposure of the face is appropriate (see, for example, Patent Document 1).

JP 2009-081607 A

  However, with the conventional strobe lighting control, strong light (a large amount of light) is emitted instantaneously, so if you want to take a picture of a sleeping subject (for example, if you want to take a picture of a sleeping face of a baby or pet), wake up the subject. There is a possibility. In other words, the conventional flash emission control may be inappropriate for shooting a sleeping subject, and when shooting a sleeping subject, a different flash emission control is required.

  The present invention has been made in view of the above problems, and an object of the present invention is to determine whether or not the subject is sleeping and to appropriately control the light emission amount and the light emission time of the light emitting means so as not to raise the sleeping subject. Is to realize.

In order to solve the above-described problems and achieve the object, the imaging apparatus of the present invention has a first emission and a longer emission time from the start to the end of one emission and a lower emission intensity than the first emission. determining a light-emitting means for the second light emission is possible, and an imaging means for generating image data by imaging an optical image of an object, whether the photographic object from the image data generated by said image pickup means is sleeping When performing imaging with light emission by the sleeping face determination means and the light emitting means, when imaging a subject that has not been determined to be sleeping by the sleeping face determination means, the first emission is performed, and the sleeping face determination means when imaging a are determined to be subject to sleep by is characterized Rukoto to have a, a light emission control means for controlling said light emitting means to perform the second light.

  According to the present invention, it is possible to determine whether or not the subject is sleeping, and to appropriately control the light emission amount and the light emission time of the light emitting means so as not to wake up the sleeping subject.

1 is a block diagram illustrating a configuration of an imaging apparatus according to an embodiment. 6 is a flowchart illustrating an image capturing operation performed by the imaging apparatus according to the present embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described in detail. The embodiment described below is an example for realizing the present invention, and should be appropriately modified or changed according to the configuration and various conditions of the apparatus to which the present invention is applied. It is not limited to the embodiment. Moreover, you may comprise combining suitably one part of each embodiment mentioned later.

  Hereinafter, an example in which the imaging apparatus of the present invention is applied to a digital still camera will be described. However, the present invention is not limited to this, and the present invention may be applied to other electronic devices having a flash photographing function.

  <Apparatus Configuration> First, the main configuration of the imaging apparatus of the present embodiment will be described with reference to FIG.

  In FIG. 1, the imaging apparatus 100 according to the present embodiment is characterized by image capturing with strobe light emission. Reference numeral 10 denotes a photographing lens. Reference numeral 12 denotes a shutter having an aperture function. An image sensor 14 converts an optical image of a subject into an electric signal. Reference numeral 16 denotes an A / D converter that converts an analog signal output from 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. Further, the image processing circuit 20 performs predetermined calculation processing using image data generated by imaging, and supplies the calculation result to the system control circuit 50.

  Based on the calculation result, the system control circuit 50 controls the exposure control unit 40 and the focus adjustment unit 42 to perform TTL (through-the-lens) AF (autofocus) processing and AE (automatic exposure) processing. , EF (flash pre-emission) processing is realized. Further, the image processing circuit 20 also performs TTL AWB (auto white balance) processing using image data generated by imaging.

  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 output from the A / D converter 16 is supplied to the memory control circuit 22 via the image processing circuit 20 or directly to the memory control circuit 22, and thereby written in the image display memory 24 or the memory 30. It is.

  Reference numeral 24 denotes an image display memory. Reference numeral 26 denotes a D / A converter. An image display unit 28 includes a TFT-LCD or the like. The display image data written in the image display memory 24 is supplied to the image display unit 28 via the D / A converter 26, whereby an image is displayed on the image display unit 28. An electronic viewfinder function can be realized by sequentially displaying images related to imaging on the image display unit 28. In addition, a playback display function and various display functions can be used by using the image display unit 28. Further, 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 imaging apparatus 100 can be significantly reduced. it can.

  A memory 30 stores captured still images and moving images. The memory 30 has a storage capacity sufficient to store a predetermined number of still images and a moving image for a predetermined time. By using this memory 30, a large number of images can be stored at high speed even in continuous shooting or panoramic shooting in which a plurality of still images are continuously shot. The memory 30 can also be used as a work area for the system control circuit 50.

  A compression / decompression circuit 32 compresses or decompresses image data by adaptive discrete cosine transform (ADCT) or the like. The compression / decompression circuit 32 reads an image stored in the memory 30, performs a compression process or an expansion process, and writes the processed data to the memory 30.

  An exposure control unit 40 controls the shutter 12 having an aperture function, and can perform flash light control in cooperation with the flash 48. Reference numeral 42 denotes a focus adjustment unit that controls focusing of the photographing lens 10. The exposure control unit 40 and the focus adjustment unit 42 are controlled by the system control circuit 50 based on the calculation result obtained by the image processing circuit 20 calculating image data generated by imaging. Thereby, TTL exposure control and focus adjustment are realized. A zoom control unit 44 controls zooming of the photographing lens 10.

  A barrier control unit 46 controls the operation of the barrier (protection unit) 102.

  The strobe 48 includes an LED light source capable of performing minute long-second light emission and minute light emission, and emits light with light emission intensity and light emission time corresponding to a control signal from the system control circuit 50. In addition, the strobe 48 can control flash light emission of normal light emission intensity and light emission time during normal light emission, and minute long-second light emission having a light emission intensity smaller and longer than normal light emission. Similarly, during the pre-light emission, it is possible to control the light emission for dimming and the minute light emission at the normal time. Further, the strobe 48 has a function of projecting AF auxiliary light for brightly illuminating the subject and facilitating focusing. The strobe 48 may be single, or a plurality of light sources such as a xenon tube for flash light emission and an LED for minute long-second light emission may be provided, and each may be switched and controlled during the main light emission. Here, the minute long-second light emission and the minute light emission mean that, in image shooting with strobe light emission, the light emission time is changed without changing the total light emission amount (integrated amount), that is, when the light emission time is long, the light emission intensity is small ( When the light is weak and the light emission time is short, the amount of light emission is controlled so that the light intensity is high (strong). As a result, since the light emission time becomes longer, the subject is illuminated with light having a low light emission intensity, so that, for example, an image can be taken so as not to wake up when shooting a sleeping face of a baby or a pet.

  Reference numeral 50 denotes a system control circuit that controls the entire imaging apparatus 100. A memory 52 stores constants, variables, programs, and the like for the operation of the system control circuit 50. The memory 52 also stores a program diagram used in AE. The program diagram is a table that defines the relationship between the aperture value for the exposure value and the control value for the shutter speed.

  Reference numeral 54 denotes a display unit such as a liquid crystal display device, which displays an operation state, a message, and the like using characters, images, and the like in accordance with execution of a program by the system control circuit 50. The display unit 54 is installed in a single or a plurality of positions near the operation unit of the imaging apparatus 100 so that the display unit 54 can be visually recognized. The display unit 54 includes, for example, a combination of an LCD, an LED, and the like. A part of the display unit 54 is 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, shutter There are speed display, aperture value display, etc. In addition, exposure compensation display, 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, and attachment / detachment of the recording medium 200 There are status display, communication I / F operation display, date / time display, and the like. 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 non-volatile memory, such as an EEPROM.

  Reference numerals 60, 62, 64, and 66 are operation units for the user to instruct the system control circuit 50 to perform various operations. For example, a switch or a dial, a touch panel, pointing by line-of-sight detection, a voice recognition device, or a combination of one or more Consists of. More specifically, 60 is a mode dial switch, which is turned off, automatic exposure mode such as program AE mode, fully automatic mode, manual exposure mode, sleeping face shooting mode, panoramic shooting mode, playback mode, multi-screen playback / erase Each mode such as a mode and a PC connection mode can be switched.

  Reference numeral 62 denotes a shutter switch SW1, which is turned on during 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 the start of operation.

  A shutter switch SW2 64 is turned on when the operation of the shutter button is completed, and an exposure process of writing image data into the memory 30 via the A / D converter 16 and the memory control circuit 22 with the signal read from the image sensor 14 being performed. Start operation. Further, a series of development processes using operations in the image processing circuit 20 and the memory control circuit 22, a recording process in which the image data is read from the memory 30, compressed by the compression / decompression circuit 32, and written to the recording medium 200. The operation start of the process is instructed.

  An operation unit 66 includes various buttons and a touch panel. The operation unit 66 includes a menu button, a set button, a cross button, and the like.

  Reference numeral 80 denotes a power supply control unit, which includes a battery detection circuit, a DC-DC converter, a switch circuit that switches blocks to be energized, and the like. The power supply control unit 80 detects the presence / absence of a battery, the type of battery, and the remaining battery level, controls the DC-DC converter based on the detection result and the instruction of the system control circuit 50, and requires the necessary voltage. It is supplied to each part including the recording medium for a period. 82 and 84 are connectors. A power source 86 includes a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, a NiMH battery, or a Li battery, an AC adapter, or the like.

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

  In the present embodiment, it is assumed that there are two interfaces and connectors for attaching the recording medium. Of course, the interface and the connector for attaching the recording medium may have a single or a plurality of systems, 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 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 interfaces 90 and 94 and the connectors 92 and 96 are configured using a PCMCIA card, a CF (compact flash) card, or the like, a LAN card, a modem card, a USB card, an IEEE 1394 card, a P1284 card. By connecting various communication cards such as SCSI cards, PHS and other communication cards, image data and management information attached to the image data can be transferred to and from other computers and peripheral devices such as printers. I can do it.

  Reference numeral 102 denotes protection means that 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 imaging device 100.

  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.

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 imaging apparatus 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, and the like, an interface 204 with the imaging device 100, and a connector 206 that connects to the imaging device 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 imaging device 100, and a connector 216 that connects to the imaging device 100.

  <Description of Operation> With reference to FIG. 2, an image capturing operation by the image pickup apparatus of this embodiment will be described. 2 is realized by the system control circuit 50 expanding and executing the program recorded in the nonvolatile memory 56 in the work area of the volatile memory 52 such as a RAM.

  The system control circuit 50 performs various shooting preparation operations when the power supply 86 is turned on in the mode in which the mode dial 60 can shoot, and starts displaying a through image on the image display unit 28 when the shooting preparation is completed. Here, the through image is an image captured by the image sensor 14 that is displayed for composition confirmation before and after capturing a still image. In the through image display state, the data sequentially written to the image display memory 24 via the image sensor 14, the A / D converter 16, the image processing circuit 20, and the memory control circuit 22 are stored in the memory control circuit 22 and the D / A. The images are sequentially displayed on the image display unit 28 via the converter 26. Thereby, an electronic viewfinder (EVF) function is realized.

  Next, an image capturing operation in the through image display state will be described with reference to FIG.

  In FIG. 2, input image data (for example, a through image) is first subjected to face detection processing in the image processing circuit 20 (S201). The face detection process may be a known method. For example, from the input image data, the shape corresponding to the constituent elements of the face area of the subject such as the nose, mouth and eyes is extracted, and the area where the nose and mouth exist on the extension line passing through the middle of both eyes is detected. . Then, the size of the face is estimated from the size of both eyes and the distance between them, and the region surrounded by the estimated size region is defined as the face region with reference to the position corresponding to the center of the nose.

  If a face can be detected in step S201, the process proceeds to step S202, and the image processing circuit 20 determines whether or not the subject is in an eye-closed state for a certain period of time. When a plurality of faces are detected, only the face determined as the main face by the image processing circuit 20 from the size or position of the face of the subject may be targeted, or all detected faces may be targeted. Good. A known method may be used to determine whether or not the eyes are in a closed state. For example, the input image data is binarized, a black region corresponding to the pupil is extracted from the binarized image, and the open / closed state of the eye is determined based on the number of continuous pixels in the vertical direction of the black region. You may judge. Alternatively, the upper and lower eyelid edges may be detected, and the eye open / closed state may be determined from the distance between the upper and lower eyelid edges. Further, the facial feature data of the eyes meditated state is registered in advance in the non-volatile memory 56 as sleeping face registration means, and the face feature data detected by the image processing circuit 20 and the registered facial feature data of the eyes meditated state are registered. May be used to identify a face in an individual's eye-meditation state.

  If the same subject that has been in a closed state for more than a certain time is detected continuously until the shutter switch (SW1) 62 is pressed, it is determined that the subject is sleeping and 1 is assigned to the sleeping face determination FLAG (step) S203). When 1 is assigned to the sleeping face determination FLAG, a message indicating that the subject is sleeping may be displayed on the display unit 54. On the other hand, if the face cannot be detected in step S201, or if it is determined in step S202 that the subject has not meditated for a certain period of time, the system control circuit 50 substitutes 0 for the sleeping face determination FLAG (step S204).

  Next, in step S205, the system control circuit 50 determines whether or not the shutter switch (SW1) 62 has been pressed. If it has been pressed, the process proceeds to step S206, but if it has not been pressed, the process returns to step S201. .

  In step S206, the system control circuit 50 determines whether or not the shutter switch (SW2) 64 has been pressed. If the shutter switch (SW2) 64 has been pressed, the process proceeds to step S207. If not, the process returns to step S205.

  In step S207, the system control circuit 50 determines whether the sleeping face determination FLAG is 1. When the sleeping face determination FLAG is not 1 (that is, 0), the flash 48 is controlled to emit light for dimming as usual (flash pre-emission) (S209), and the subsequent main light emission is also performed with normal flash light emission. An image is taken (S211).

  On the other hand, if the sleeping face determination FLAG is 1 in S207, the flash 48 is controlled to emit a minute light for dimming (S208), and in the subsequent main light emission, an image is captured with a minute long-second light emission based on the dimming result (S210). ). In step S210, the minute long-second light emission is performed as long as the final total light emission amount is equal regardless of the light emission intensity of the strobe 48, and the subject is necessary by continuously emitting light during the exposure time. This is to compensate for the amount of light. However, here, if the minute light emission at the time of light emission for dimming does not reach the subject, the main light emission may be made non-light emission.

  If the sleeping face FLAG is 1 in step S207, the shutter sound of the sound generation element, the member operation sound, etc. may be turned off. Further, the system control circuit 50 may perform control so that AF auxiliary light is not emitted when the shutter switch (SW1) 62 is pressed.

  In the present embodiment, the subject is not limited to a person, but the same processing can be performed for an animal other than a person.

  As described above, according to the present embodiment, when photographing a sleeping face, it is possible to photograph a subject brightly with appropriate light emission control without taking time and effort.

  <Modification> In the above-described embodiment, when the sleeping face FLAG is 1 in step S207, the strobe 48 is controlled to emit a minute light for dimming (S208). An image was captured by light emission (S210). On the other hand, control may be performed so that an image is captured without light emission for light control and without light emission of main light emission. In this way, when photographing a sleeping face, it is possible to shoot without worrying about causing a subject more than in the above-described embodiment without taking time and effort. That is, it can be said that it is a photographing mode in which priority is given to not raising a subject.

  It should be noted that a mode in which strobe light emission control as in the above-described embodiment is performed may be a sleeping face photographing mode, and the user may arbitrarily set the mode. In this case, when the sleeping face photographing mode is set, it may be configured to display the user so as to be identifiable. Further, when there is a subject sleeping even within the shooting angle of view, the sleeping face shooting mode may be set.

  Further, the sleeping face photographing mode may be maintained even when the subject moves or the eyes are opened after the pre-light emission or while SW1 is on. Furthermore, the light emission intensity at the time of minute light emission may be changed depending on the distance to the subject, and the sleeping face photographing mode may not be set when the subject is farther than a predetermined distance.

  In addition, if the light emission time is too long when emitting light for a very long time, a good image cannot be captured due to the influence of camera shake, subject movement, and the like. For this reason, instead of increasing the light emission time, the exposure sensitivity may be compensated by increasing the photographing sensitivity or opening the aperture to reduce the light emission intensity. In this case, any configuration that controls at least one of the aperture and the imaging sensitivity may be used.

  [Other Embodiments] The present invention is also realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, etc.) of the system or apparatus reads and executes the program code. It is processing to do. In this case, the program and the storage medium storing the program constitute the present invention.

Claims (11)

A light emitting means capable of performing a first light emission and a second light emission having a longer light emission time from the start to the end of the first light emission than the first light emission and a lower light emission intensity ;
Imaging means for capturing an optical image of a subject to generate image data;
A sleeping face determining means for determining whether the subject is in sleeping from the image data generated by said image pickup means,
When imaging with light emission by the light emitting means, when imaging a subject that is not determined to be sleeping by the sleeping face determining means, the first light emission is performed and the sleeping face determining means is sleeping. imaging device when imaging the determined subject, wherein Rukoto to have a, a light emission control means for controlling said light emitting means to perform the second light. The first light emission is a flash emission of the light emitting means ,
The second emission, the imaging apparatus according to claim 1, characterized in that a long shutter onset light of the light emitting means.   The light emission control means controls the light emission intensity of the light emission means according to the distance to the subject when imaging a subject determined to be sleeping by the sleeping face determination means. Or the imaging device of 2. It said light emission control means, in the case of imaging a subject is determined that sleeping by the sleeping face determination unit, when the distance to the subject is the second distance emission does not reach the light emitting means The imaging apparatus according to claim 3 , wherein the light emitting unit is controlled so as not to perform the second light emission.   The imaging apparatus according to claim 1, wherein the light emitting unit includes an LED light source.   The sleeping face determination unit determines that the subject corresponding to the face is sleeping when the subject corresponding to the face detected from the image data generated by the imaging unit is in a state of being in a closed state for a certain time or more. The imaging device according to any one of claims 1 to 5, wherein It further has a registration means for registering sleeping face feature data in advance,
The sleeping face determination means determines whether or not the subject is sleeping by comparing the facial feature data detected from the image data generated by the imaging means with the sleeping face feature data registered in the registration means. The imaging apparatus according to claim 6 , wherein the determination is performed.   The light emission control means is a case where a plurality of faces are detected from the image data generated by the imaging means, and the sleeping face determination means determines that a subject corresponding to at least one face is sleeping. The imaging apparatus according to claim 6 or 7, wherein the light emitting unit is controlled to perform the second light emission. A light emitting means capable of performing a first light emission and a second light emission having a longer light emission time from the start to the end of the first light emission than the first light emission and a lower light emission intensity ;
An image pickup means for picking up an optical image of a subject and generating image data;
A sleeping face determination step of determining whether the subject is in sleeping from the image data generated by said image pickup means,
When imaging with light emission by the light emitting means, when imaging a subject that has not been determined to be sleeping in the sleeping face determination step, the first light emission is performed, and the subject is sleeping in the sleeping face determination step. control method when imaging the determined subject, wherein Rukoto to have a, a light emission control step of controlling the light emitting means to perform the second light. The program for functioning a computer as each means of the imaging device of any one of Claims 1 thru | or 8 . A computer-readable storage medium storing a program for causing a computer to function as each unit of the imaging apparatus according to any one of claims 1 to 8 .

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