JP2008098739A - Imaging apparatus, image processing method used for imaging apparatus, and program for causing computer to execute the image processing method - Google Patents

Abstract

An object of the present invention is to quickly perform appropriate photographing according to a photographer's preference when photographing a human face.
In an imaging apparatus including a display unit that displays an image captured by an imaging element, a face detection circuit that detects a human face included in the captured image, and a detected face. An HI control circuit 180 that extracts a corresponding face image from an image captured by the image sensor 120 and an HI control circuit 180 that displays the face image extracted by the face image extraction unit on the display unit 300 are provided. In addition, a switch 211 that selects a face image displayed on the display unit 300 is provided, and a focal length that has a predetermined composition ratio in an image in which the face of the subject corresponding to the selected face image is captured by the image sensor 120. The appropriate focal length is calculated, and the calculated appropriate focal length is displayed on the display unit 300.
[Selection] Figure 1

Description

  The present invention relates to an imaging apparatus such as a digital still camera, and more particularly to an imaging apparatus suitable for photographing a person's face as a subject, an imaging method, a processing method therefor, and a program for causing a computer to execute the method.

  2. Description of the Related Art Conventionally, as an imaging device that captures a person's face as a subject, an image captured using an imaging element such as a CCD (Charge Coupled Devices) is converted into an electrical signal, and the converted electrical signal is stored as digital data in a storage medium. There is a digital still camera to memorize.

  As for the digital still camera, many techniques have been proposed for detecting a predetermined image portion from digital data corresponding to a captured image (captured image) while improving the processing capability of hardware. In addition, various techniques for accurately detecting a human face portion from digital data corresponding to a photographed image have been proposed, and a technique for detecting a plurality of face portions from digital data corresponding to a photographed image has been proposed.

For example, the size and position of a human face part included in the input image are obtained based on the skin color part and the facial feature amount included in the input image, and the face is determined according to the size and position of the face part. There has been proposed an imaging apparatus that controls the zoom lens so that the size of the area becomes the size of a bust shot (for example, see Patent Document 1). Note that the bust shot is to photograph a portion (including a face) above the person's chest when photographing a person.
Japanese Patent Laid-Open No. 06-217187 (FIG. 4)

  In the above-described conventional technology, when photographing a human face part included in the photographing range displayed on the liquid crystal display (LCD) of the digital still camera, an appropriate zoom can be performed on the face part. Appropriate bust shot can be performed.

  By the way, when a plurality of persons are photographed with a digital still camera, the zoom lens is adjusted so that the plurality of persons fall within the photographing range. For example, when each person is photographed from a plurality of persons after the photographing, an appropriate bust shot can be performed using the above-described conventional technique.

  However, when photographing a human face, there are a composition suitable for a bust shot and a composition unsuitable for a bust shot depending on the orientation and background of the face of the person to be photographed. For example, after shooting as described above, when selecting and shooting an individual with a photographer's favorite composition from multiple persons, use the zoom function to check the composition with the shooting range as the size of the bust shot. There is a need to. For this reason, the photographing time becomes long, and appropriate photographing according to the photographer's preference cannot be performed quickly.

  In other words, it is not possible to quickly perform appropriate shooting according to the photographer's preference when shooting an individual with a photographer's favorite composition from a plurality of persons included in the shooting range. was there.

  Therefore, an object of the present invention is to quickly perform appropriate photographing according to a photographer's preference when photographing a human face.

  The present invention has been made to solve the above problems, and a first aspect of the present invention is an image pickup apparatus including a display means for displaying an image picked up by the image pickup means, and is picked up by the image pickup means. Face detection means for detecting a human face included in the image, face image extraction means for extracting a face image corresponding to the face detected by the face detection means from the image captured by the imaging means, and the face image extraction An image pickup apparatus, a display control means for displaying the face image extracted by the means on the display means, an image processing method used in the image pickup apparatus, and a program for causing a computer to execute the image processing method . As a result, the image captured by the imaging unit is displayed on the display unit, and when a human face is included in the image captured by the imaging unit, a face image corresponding to the face is captured by the imaging unit. This brings about the effect that the image is taken out and displayed on the display means.

  In the first aspect, at least a part of the display unit includes a captured image display area and a face image display area, and the display control unit converts the image captured by the imaging unit into the captured image. While displaying in the display area, the face image extracted by the face image extracting means can be displayed in the face image display area. Thereby, the effect | action that the image imaged by the imaging means and the face image taken out by the face image extraction means can be displayed on the predetermined area | region of a display means is brought about.

  In the first aspect, the image processing apparatus further includes a face image selection unit that selects a face image displayed on the display unit, and the display control unit indicates that the face image is selected by the face image selection unit. Can be displayed on the display means. Thereby, in order to make it easy to recognize the face image selected by the face image selection means, the effect that the face image is selected can be displayed on the display means.

  In the first aspect, the photographing condition setting means for setting photographing conditions for the face of the subject corresponding to the face image selected by the face image selecting means based on the face image extracted by the face image extracting means. Can be provided. Thereby, when photographing the face of the subject corresponding to the face image selected by the face image selecting means, the photographing condition can be easily set.

  In the first aspect, the display control unit can convert the face image extracted by the face image extraction unit into a predetermined size and display the converted image on the display unit. This brings about the effect that the face image extracted by the face image extracting means is displayed on the display means with a predetermined size.

  In the first aspect, when the face detection unit detects a plurality of faces by the face detection unit, the face detection unit extracts a plurality of face images corresponding to the plurality of detected faces by the imaging unit. Taking out from the captured image, the display control means can cause the display means to display a plurality of face images taken out by the face image taking means. Thereby, when a plurality of human faces are included in the image picked up by the image pickup means, the face image corresponding to the plurality of faces can be displayed on the display means.

  In the first aspect, at least a part of the display means is provided with a face image display area, and the display control means outputs a plurality of face images extracted by the face image extraction means according to a predetermined condition. A list can be displayed side by side in the face image display area. Thus, when a plurality of human faces are included in the image captured by the imaging unit, the face images corresponding to the plurality of faces are displayed in a list in a face image display area according to a predetermined condition. It brings about the effect of being able to

  According to a second aspect of the present invention, there is provided an image pickup apparatus comprising a display means for displaying an image picked up by the image pickup means, and a face detection means for detecting a human face included in the image picked up by the image pickup means. A face image extracting unit that extracts a face image corresponding to the face detected by the face detecting unit from an image captured by the imaging unit, and a face image extracted by the face image extracting unit is displayed on the display unit. A face image display control means to be operated, a face image selection means for selecting a face image displayed on the display means, and a face of a subject corresponding to the face image selected by the face image selection means is imaged by the imaging means. An appropriate focal length, which is a focal length having a predetermined composition ratio in the obtained image, is based on the current focal length and the size of the face image extracted by the face image extracting means. And a focal length display control means for displaying on the display means an appropriate focal length calculated by the focal distance calculation means. And a program for causing a computer to execute the image processing method. Thus, when a human face is included in the image captured by the imaging unit, the face image corresponding to the face is extracted from the image captured by the imaging unit and displayed, and the displayed face image is displayed. When selected, an appropriate focal length, which is a focal length having a predetermined composition ratio in an image captured by the imaging unit, of the subject corresponding to the selected face image is calculated, and the calculated appropriate This brings about an effect that the focal length can be displayed.

  In the second aspect, at least a part of the display unit is provided with a focal length display area for displaying a current focal length, and the focal length display control unit is calculated by the focal length calculation unit. An appropriate focal length can be displayed in the focal length display area. This brings about the effect that the calculated proper focal length can be displayed in the focal length display area.

  Further, in this second aspect, the focal length calculation means has a focal point that has a predetermined composition ratio in the image of the face of the subject corresponding to the face image selected by the face image selection means. A focal length range indicating a certain range of distance is calculated based on the calculated appropriate focal length, and the focal length display control means displays the focal length range calculated by the focal length calculation means as the focal length display. It can be displayed in the area. As a result, based on the appropriate focal length, the focal length range indicating the fixed range of the focal length that has a predetermined composition ratio in the image captured by the imaging unit of the face of the subject corresponding to the selected face image is calculated. And the calculated focal length range can be displayed in the focal length display area.

  In the second aspect, the focal length display region is a rod-shaped region in which one end portion indicates the telephoto side and the other end portion indicates the wide-angle side. In the distance display area, the current focal length is displayed by displaying the position according to the current focal length value in a color different from that of other portions, and the focal length range calculated by the focal length calculation means is displayed. The focal length range can be displayed by displaying a portion corresponding to the value in a color different from that of the other portions. As a result, in the focal length display area, which is a rod-shaped area where one end indicates the telephoto side and the other end indicates the wide-angle side, the position corresponding to the current focal length value is a different color from the other parts. The current focal length can be displayed by displaying the current focal length, and the focal length range can be displayed by displaying the portion corresponding to the calculated focal length range value in a different color from the other portions. Bring.

  Further, in the second aspect, the apparatus further comprises gender discrimination means for discriminating the gender of the person related to the face based on the face image corresponding to the face detected by the face detection means, and the focal length calculation means includes The proper focal length calculated above can be corrected according to the determined gender. This brings about an effect that an appropriate focal length can be corrected according to the sex determined based on the face image corresponding to the detected face.

  In addition, in the second aspect, the camera further includes a shooting mode setting unit that sets a shooting mode that is a shooting condition for shooting the subject, and the focal length calculation unit is configured to perform the above-described shooting mode according to the set shooting mode. The calculated proper focal length can be corrected. This brings about an effect that an appropriate focal length can be corrected according to the set photographing mode.

  According to a third aspect of the present invention, a human face included in an image captured by the imaging unit is detected in an imaging apparatus including a display unit that displays an image captured by the imaging unit and a zoom lens. A face detection means for extracting the face image corresponding to the face detected by the face detection means from the image captured by the imaging means, and the face image extracted by the face image extraction means described above. The face image display control means to be displayed on the display means, the face image selection means for selecting the face image displayed in the display area, and the face of the subject corresponding to the face image selected by the face image selection means An appropriate focal length, which is a focal length having a predetermined composition ratio in an image picked up by the image pickup means, is a current focal length and a face image extracted by the face image extraction means. An imaging apparatus comprising: a focal length calculation unit that calculates based on a size; and a zoom lens control unit that controls the zoom lens based on an appropriate focal length calculated by the focal length calculation unit. An image processing method used in an imaging apparatus and a program for causing a computer to execute the image processing method. Thus, when a human face is included in the image captured by the imaging unit, the face image corresponding to the face is extracted from the image captured by the imaging unit and displayed, and the displayed face image is displayed. When selected, an appropriate focal length, which is a focal length having a predetermined composition ratio in an image captured by the imaging unit, of the subject corresponding to the selected face image is calculated, and the calculated appropriate The zoom lens can be controlled based on the focal length.

  In the third aspect, when the face detecting unit detects a plurality of faces by the face detecting unit, the face detecting unit extracts a plurality of face images corresponding to the detected plurality of faces by the imaging unit. The plurality of face images extracted from the captured image and displayed by the face image extraction unit are displayed on the display unit, and among the plurality of faces corresponding to the plurality of face images displayed on the display unit Display control means for displaying on the display means that a face image corresponding to a face within the same depth of field as the focus position of the zoom lens controlled by the zoom lens control means is in focus. can do. Thereby, when a plurality of faces are detected, a plurality of face images extracted from the image captured by the imaging unit are displayed, and among the plurality of faces corresponding to the plurality of displayed face images For the face image corresponding to the face within the same depth of field as the focus position of the zoom lens controlled in step (b), it is displayed that the in-focus state is displayed.

  According to the present invention, when photographing a human face, it is possible to achieve an excellent effect that it is possible to quickly perform appropriate photographing according to the photographing situation and the photographer's preference.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram illustrating a functional configuration example of an imaging apparatus 100 according to an embodiment of the present invention.

  The imaging apparatus 100 includes an optical system 110, an imaging element 120, a camera signal processing circuit 130, a buffer memory 140, an image processing circuit 150, a camera control circuit 160, a lens driver 170, an HI control circuit 180, Motors 190 and 191, an exposure driving part 200, an operation unit 210, and a display unit 300 are provided. The imaging apparatus 100 is, for example, a digital still camera that records still images or a digital video camera that records moving images.

  Note that the imaging apparatus 100 is provided with a plurality of shooting modes. The shooting mode is a shooting condition when shooting a subject. Shooting modes include, for example, a normal mode used for normal shooting, a portrait mode used for taking a person as a subject, a landscape mode used for shooting a landscape, and a dark place. There is a night view mode. In the present embodiment, the face detection mode will be described in detail. In the imaging apparatus 100, the face detection mode and other shooting modes can be set simultaneously.

  The optical system 110 is an optical system of the imaging apparatus 100 including a plurality of lenses including a zoom lens and a focus lens.

  The image sensor 120 photoelectrically converts an image photographed through the optical system 110 into an image signal (electric signal) and outputs the photoelectrically converted image signal to the camera signal processing circuit 130. As the imaging element 120, for example, there is a CCD (Charge Coupled Device) that captures an image of a predetermined subject.

  The camera signal processing circuit 130 performs appropriate signal processing on the image signal photoelectrically converted by the image sensor 120 and outputs the image signal to the buffer memory 140. The camera signal processing circuit 130 performs signal communication necessary for camera control with the camera control circuit 160.

  The buffer memory 140 is a buffer memory that temporarily stores the image signal output from the camera signal processing circuit 130 and outputs the stored image signal to the image processing circuit 150.

  The image processing circuit 150 performs conversion for outputting an image signal input from the camera signal processing circuit 130 via the buffer memory 140 to the display unit 300 or an external device.

  The camera control circuit 160 is a control circuit that controls the entire imaging apparatus 100. In addition, the camera control circuit 160 performs signal communication with the lens driver 170 and controls the exposure driving part 200 in order to control each lens constituting the optical system 110.

  The lens driver 170 is a lens driver that controls motors 190 and 191 attached to a predetermined lens constituting the optical system 110 in accordance with an instruction from the camera control circuit 160.

  A HI (Human Interface) control circuit 180 controls the image processing circuit 150 based on operation information input from the operation unit 210 and various information input from the camera control circuit 160.

  Motors 190 and 191 are motors that are attached to predetermined lenses constituting the optical system 110 and move the position of each lens based on the control of the lens driver 170.

  The exposure driving part 200 is a part that controls the total amount of light entering the image sensor 120 based on the control of the camera control circuit 160.

  The operation unit 210 is an operation unit that inputs various types of operation information from the user, and outputs the input operation information to the HI control circuit 180. The operation unit 210 is provided with a switch 211 for face selection. As the switch 211, for example, up / down arrow keys and up / down / left / right cross keys are conceivable.

  FIG. 2 is a diagram illustrating an example of an image display displayed on the display unit 300.

  The display unit 300 is a display unit that displays various image information output from the image processing circuit 150 based on the control of the HI control circuit 180. For example, a liquid crystal display (LCD) or an electronic viewfinder (EVF) is used as the display unit. In the normal shooting mode, the image captured by the image sensor 120 is displayed on the display unit 300 as it is. On the other hand, when the face detection mode is set, the display unit 300 is provided with a captured image display area 310 and a face selection display area 320 as shown in FIG.

  A focal length display bar 311 is displayed in the captured image display area 310. In the focal length display bar 311, the current focal length 312 and the appropriate focal length 313 are displayed. The focal length display bar 311 is a zoom bar used when operating the zoom lens, and indicates the range of the focal length that the imaging apparatus 100 can shoot. The current focal length 312 is a display showing the current focal length. The proper focal length 313 is a display indicating the range of the proper focal length when the selected face is photographed when the face detection mode is set.

  That is, the focal length display bar 311 is a rod-like focal length display region in which one end portion indicates the telephoto side and the other end portion indicates the wide angle side. In addition, the current focal length 312 is displayed by displaying the position corresponding to the current focal length value in the focal length display bar 311 in a different color from the other portions. Further, the appropriate focal length 313 is displayed by displaying the portion corresponding to the value of the appropriate focal length range in a different color from the other portions. However, in FIGS. 2, 4, and 5, the appropriate focal length 313 is indicated by hatching. The focal length is a value indicating the distance from the entire lens constituting the optical system 110 to the image sensor 120.

  In the face selection display area 320, human face images included in the captured image display area 310 are displayed side by side in a predetermined size.

  For example, FIG. 2 shows an example in which each person's face is displayed in the photographed image display area 310 in the case of photographing with four family members of a younger brother H1, a father H2, a mother H3, and an older sister H4. In this case, the face image H1a of the younger brother H1 is displayed in the first display area 321, the face image H2a of the father H2 is displayed in the second display area 322, and the face image of the mother H3 is displayed in the third display area 323. H3a is displayed, and the face image H4a of the sister H4 is displayed in the fourth display area 324. This arrangement order may be based on the size of the detected face, or may be arranged in the order of accuracy of the detected face image.

  Next, the camera signal processing circuit 130 will be described in more detail.

  FIG. 3 is a block diagram illustrating a functional configuration example of the camera signal processing circuit 130.

  The camera signal processing circuit 130 includes an I / F (interface) circuit 131, a detection circuit 132, a camera image signal processing circuit 133, a face detection circuit 134, a memory I / F circuit 135, and an I / F circuit 136. A bus 137 and a bus 138.

  The I / F circuit 131 is an I / F circuit that, when an image signal converted by the image sensor 120 is input, outputs the input image signal to the memory I / F circuit 135 via the bus 137.

  The detection circuit 132 performs detection processing for acquiring various types of information necessary for camera control from the image signal input to the memory I / F circuit 135, and sends the acquired various types of information to the camera control circuit 160 using the I / F circuit 136. It is a detection circuit which outputs via. The information acquired by the detection circuit 132 is information necessary for control of image brightness, contrast information, color discrimination, etc., and white balance, hue matching, AE, AF, and the like.

  The camera image signal processing circuit 133 performs camera image processing such as linear matrix processing, white balance processing, and γ correction processing on the image signal input to the memory I / F circuit 135.

  The camera control circuit 160 shown in FIG. 1 performs camera control calculation processing based on various information acquired by the detection processing of the detection circuit 132, and sets the control parameters determined by this camera control calculation processing to the I / F circuit 136. To the camera image signal processing circuit 133. The camera image signal processing circuit 133 performs camera image processing based on the control parameters output from the camera control circuit 160.

  The face detection circuit 134 is a face detection circuit that detects a human face included in an image signal subjected to camera image processing by the camera image signal processing circuit 133. If a human face is detected, face detection information, which is information indicating that a human face has been detected, is output to the camera control circuit 160 via the I / F circuit 136. As an example of face detection, there is face detection based on a skin color portion included in a photographed image, a feature amount of a human face, or the like. The face detection information includes the coordinate position of the detected face image area, the area information of the detected face image (the center coordinates of the face image, the size of the face image in the horizontal and vertical directions, etc.), A numerical value indicating the orientation, the size of the face, the accuracy of the detected face image, and the like are included.

  When the image signal converted by the image sensor 120 is input via the I / F circuit 131, the memory I / F circuit 135 receives the input image signal as a detection circuit 132, a camera image signal processing circuit 133, and a face detection circuit 134. And a memory I / F circuit that outputs data via the bus 137 at the same time. Also, the camera image signal processing circuit 133 outputs an image signal subjected to camera image processing to the buffer memory 140.

  The I / F circuit 136 is an I / F circuit for transmitting / receiving various types of information to / from the camera control circuit 160.

  Next, a method for displaying a human face image included in a captured image displayed in the captured image display area 310 of the display unit 300 in each of the display areas 321 to 324 of the face selection display area 320 will be described.

  4A is a diagram illustrating an example of image display displayed in the captured image display area 310 and the face selection display area 320 of the display unit 300, as in FIG. 2, and FIG. It is a figure which shows the face image of father H2 contained in the image display area 310. FIG.

  Here, as shown in FIG. 4B, the face image of the father H2 displayed in the captured image display area 310 of the display unit 300 is extracted, and the extracted face image of the father H2 is displayed in the face selection display area 320. A case where the face image H2a to be displayed in the second display area 322 is generated will be described.

  When a human face image displayed in the captured image display area 310 is extracted, the face detection information output by the face detection circuit 134 is referred to. Here, the area information of the face image included in the face detection information is used.

  First, based on the area information included in the face detection information, area calculation is performed to extract the face image of father H2 displayed in the captured image display area 310. Specifically, as shown in FIG. 4B, the center coordinates 401 (Xo, Yo) of the face image of the father H2, the value X1 indicating the size of the face image in the horizontal direction, and the size in the vertical direction are set. The indicated value Y1 is used.

  The face image area H2b indicated by X1 × Y1 is a rectangular area to the extent that most of the face image is included, as shown in FIGS. 4 (a) and 4 (b). However, in order to display the entire face in the face selection display area 320, the face image area to be extracted needs to be an area including the entire face. That is, the extracted face image area H2c is larger than the face image area H2b included in the face image area information.

Since the face image area H2c extracted in this manner is an area including the entire face, the area calculation is performed based on the face image area H2b (X1 × Y1) included in the face image area information. An example of this calculation, may be set a predetermined ratio B, and using (Equation 1) below, calculation will be described for obtaining the value X1 ₁ showing the horizontal size of the area taken. Further, for the values Y1 ₁ showing the vertical size of the area to take out, then ask the similarly calculated using the following (Equation 2).
X1 ₁ = B · X1 (Formula 1)
Y1 ₁ = B · Y1 (Formula 2)

The face image of the father H2 with the coordinates 401 (Xo, Yo) as the center is taken as the captured image display area so as to be the image area H2c of the value X1 ₁ × Y1 ₁ obtained using (Expression 1) and (Expression 2). The image is extracted from the image displayed at 310.

Subsequently, the extracted face image of the father H2 (image region H2c) is resized so that the value indicating the horizontal size is within Xs and the value indicating the vertical size is within Ys. Specifically, as for the horizontal size, the value indicating the horizontal size of the display area of the face image display area 320 and the face image value X11 _{1 of} the father H2 extracted using (Equation 3). C1 which is a ratio to Xs is calculated and the vertical size is obtained by using (Equation 4), the value Y11 _{1 of the} extracted face image of the father H2 and the display area of the face selection display area 320 C2 which is a ratio with the value Ys indicating the size in the vertical direction is calculated.
X1 ₁ / Xs = C1 (Formula 3)
Y1 ₁ / Ys = C2 (Formula 4)

Subsequently, the value C1 obtained by using (Expression 3) and (Expression 4) is compared with the value C2, and the larger value among the values C1 and C2 is determined as C3. Subsequently, using the determined C3 and the following (Equation 5), a value Xs1 indicating the horizontal size of the display area of the face image displayed in the display area of the face selection display area 320 is calculated.
Xs1 = 1 / C3 × X1 ₁ (Formula 5)

Also, using the determined C3 and the following (Equation 6), a value Ys1 indicating the vertical size of the display area of the face image displayed in the display area of the face selection display area 320 is calculated.
Ys1 = 1 / C3 × Y1 ₁ (Formula 6)

For example, when the extracted face image value X1 ₁ is larger than Xs, or when Y1 ₁ is larger than Ys, the image area H2c of X1 ₁ × Y1 ₁ is extracted so as to be within Xs × Ys. Reduce the face image. On the other hand, smaller than the value X1 ₁ of the extracted face image is Xs, and, if Y1 ₁ is smaller than Ys may be used as the size of the extracted face image, X1 ₁ × Y1 ₁ The image area H2c may be enlarged so as to be within the range of Xs × Ys.

A part of the extracted image area (for example, X1 ₁ × Y1 ₁ ) may include a part of another person's face image, but in this embodiment, another person included in the extracted image area. The display of a part of the face image of is omitted. When only the face part image can be extracted, only the face part image may be extracted and the extracted face part image may be used.

  Subsequently, the face image reduced or the like is displayed in any one of the display areas 321 to 324 of the face selection display area 320 so as to be within the range of the display area of Xs × Ys. The display position when a plurality of face images are displayed in the display areas 321 to 324 of the face selection display area 320 is determined based on the size of the face included in the face detection information, the accuracy of the face image, and the like. Alternatively, they may be arranged in the order of processing.

  Each of these processes is performed on a plurality of detected face images.

  After all the face images of the plurality of detected face images have been displayed in the display areas 321 to 324 of the face selection display area 320, the non-select button 331 is displayed in the fifth display area 330 of the face selection display area 320. Is displayed.

  Note that the number and size of each display area of the face selection display area 320 may be modified according to the number of detected face images. Also, when the number of display areas in the face selection display area 320 is fixed and more face images are detected, the face images cannot be arranged and displayed in a predetermined order in each display area. You may make it display a face image by scroll operation. Further, when the number of face images to be displayed is small, the non-selection button 331 may be sequentially displayed in a display area where no face image is displayed.

  Next, when each image shown in FIG. 2 is displayed on the display unit 300, from among the faces of the younger brother H1, father H2, mother H3, and sister H4 displayed in the captured image display area 310, A case where the face of a person who is a subject to be photographed is selected will be described.

  As shown in FIG. 2, the faces of the younger brother H1, the father H2, the mother H3, and the older sister H4 displayed in the captured image display area 310 are displayed in the display areas 321 to 324 in the face selection display area 320. ing. In such a state, the user uses the switch 211 of the operation unit 210 to select any of the faces displayed in the display areas 321 to 324 of the face selection display area 320.

  For example, when the face image of the father H2 is selected, the display is shaded in the second display area 322 in which the face image H2a of the father H2 is displayed. In the present embodiment, as shown in FIG. 2, the area where the selected face image (selected face image) is displayed is displayed with diagonal lines, but the other area and the selected area are displayed in different colors. The selected face image may be enlarged so as to be a predetermined size (for example, 1.5 times) so that the selected face image can be easily seen and can be distinguished from other regions. It may be. Moreover, you may enable it to identify another area | region and the selected area | region with another display method. Further, the selected face image is displayed so that it can be identified, and the image portion corresponding to the selected face image among the images displayed in the captured image display area 310 can be identified by shading display or the like. May be.

  When a face displayed in the face selection display area 320 is selected, an appropriate focal length 313 indicating an appropriate focal length range when the selected face is imaged is a focal point of the captured image display area 310. It is displayed on the distance display bar 311. That is, the appropriate focal length 313 displayed on the focal length display bar 311 is a constant focal length that is a predetermined component ratio in an image of the face of the subject corresponding to the selected face image captured by the image sensor 120. Indicates the range.

  When the zoom button (not shown) or the like of the operation unit 210 is operated so that the current focal length 312 falls within the range of the appropriate focal length 313 displayed on the focal length display bar 311, the selected face is displayed. It is possible to take a picture so as to have an appropriate size.

  Next, a focal length calculation method for displaying an appropriate focal length 313 on the focal length display bar 311 will be described with reference to FIG. Note that the calculation method described below is a calculation method using the property that the focal length and the display size displayed in the captured image display area 310 are proportional.

First, when a value indicating an appropriate face size in the horizontal direction with respect to the captured image display area 310 is X and a value indicating the horizontal size of the captured image display area 310 is Xa, The appropriate ratio A is obtained using (Expression 7) shown.
X / Xa = A (Formula 7)

Subsequently, based on the value X1 indicating the size of the image area included in the face detection information and the value indicating the horizontal size of the captured image display area 310 based on Xa, the following (Equation 8) is used. The current ratio A1 is obtained.
X1 / Xa = A1 (Formula 8)

Subsequently, when the value indicating the current focal length is set to Z1, based on the appropriate ratio A obtained above and the current ratio A1, an appropriate focal length is obtained using (Equation 9) shown below. Find Z.
Z = Z1 × A / A1 (Formula 9)

  Note that the appropriate focal length Z obtained above is given a predetermined width as the focal length information so that photographing according to the photographer's preference can be performed. For example, when the value of the predetermined width is set to 0.5 times in the horizontal direction and the vertical direction, and the appropriate focal length Z is 2.0, the proper focal length is 1.75. A value of ˜2.25 is an appropriate focal length range (focal length range). In addition, when the predetermined width is set to 20% and the appropriate focal length Z is 2.0, a value of 1.8 to 2.2 is appropriate as an appropriate focal length. This is the focal length range.

  Subsequently, the obtained focal length range is displayed on the focal length display bar 311 as an appropriate focal length 313. In FIGS. 2, 4, and 5, an appropriate focal length 313 is indicated by hatching.

  FIG. 5A shows the captured image display area 310 when the current focal length 312 is set to the lowest value (wide end side) of the range indicated by the appropriate focal length 313 displayed on the focal length display bar 311. It is a figure which shows the example of a display.

  FIG. 5B shows the captured image display area 310 when the current focal length 312 is adjusted to the maximum value (tele end side) of the range indicated by the appropriate focal length 313 displayed on the focal length display bar 311. It is a figure which shows the example of a display.

  As shown in FIG. 5, when the current focal length 312 is set within the range of the appropriate focal length 313 displayed on the focal length display bar 311, the selected human face is set to an appropriate size. Can be displayed. As a result, the selected human face can be photographed with an appropriate size.

  The appropriate focal length 313 of the focal length display bar 311 is continuously displayed until a predetermined time elapses or until a predetermined operation is performed.

  In each display area of the face selection display area 320, human faces detected from images displayed in the captured image display area 310 of the display unit 300 are sequentially displayed. However, instead of sequentially displaying the human faces detected in this way, each face displayed in each display area of the face selection display area 320 until a predetermined time elapses or a predetermined operation is performed. You may make it display until it is performed.

  Next, the operation of the imaging apparatus 100 according to the embodiment of the present invention will be described with reference to the drawings. Each operation shown below is an operation executed when the face detection mode is set in the imaging apparatus 100.

  Various methods for setting the imaging apparatus 100 to the face detection mode are conceivable. For example, the face detection mode may be entered by pressing a face detection button (not shown) provided on the operation unit 210. Further, the face detection mode may be set from the menu display on the display unit 300, or the face detection mode may be automatically set when a human face is included in the captured image. .

  FIG. 6 is a flowchart showing a processing procedure for displaying the detected face image by the HI control circuit 180.

  First, it is determined whether face detection information is input from the camera control circuit 160 (step S900).

  If face detection information is not input from the camera control circuit 160 (step S900), the image processing circuit 150 is controlled so that the display unit 300 displays that no face is detected. For example, the non-selection button 331 is displayed in each display area of the face selection display area 320 of the photographed image display area 310 (step S904).

  On the other hand, as shown in FIG. 2, when a face is included in the image displayed in the captured image display area 310, face detection information is input from the camera control circuit 160 (step S900).

  When face detection information is input from the camera control circuit 160 (step S900), using (Equation 1) and (Equation 2), a face image area extracted from an image displayed in the captured image display area 310 Is obtained by calculation (step S901).

  Subsequently, the face image of the area calculated in step S901 is extracted from the image displayed in the captured image display area 310, and the size of the extracted face image is the display area of the face selection display area 320. Image processing such as reduction is performed on the extracted face image using (Equation 3) to (Equation 6) so as to fall within the range (step S902).

  Subsequently, the face image subjected to image processing such as reduction in step S902 is displayed in any one of the display areas 321 to 324 in the face selection display area 320 (step S903).

  Subsequently, for all face images of the plurality of detected face images, after the display in the display areas 321 to 324 of the face selection display area 320 is completed, the face selection display area 320 in which no face image is displayed is displayed. A non-selection button 331 is displayed in the display area (step S904).

  FIG. 7 is a flowchart showing a face selection processing procedure by the HI control circuit 180.

  First, it is determined whether or not a face image is displayed in each of the display areas 321 to 324 of the face selection display area 320 (step S910).

  If no face image is displayed in each of the display areas 321 to 324 of the face selection display area 320 (step S910), the face selection process ends.

  On the other hand, if a face image is displayed in each of the display areas 321 to 324 of the face selection display area 320 (step S910), the switch 211 is pressed based on the operation information from the operation unit 210, and the face selection display area 320 is displayed. It is determined whether any of the faces displayed in the display areas 321 to 324 has been selected (step S911).

  If none of the faces displayed in the display areas 321 to 324 of the face selection display area 320 has been selected (step S911), the face selection process ends.

  If any of the faces displayed in the display areas 321 to 324 of the face selection display area 320 is selected (step S911), for example, the display area where the selected face image is displayed is, for example, shaded. It is displayed (step S912).

  Subsequently, selected face information that is information relating to the selected face image is output to the camera control circuit 160 (step S913).

  When the non-selection button 331 of the face selection display area 320 is selected in step S911, for example, the display area where the non-selection button 331 is displayed is shaded, for example (step S912), and the non-selection button Non-selection information, which is information indicating that 331 has been selected, is output to the camera control circuit 160 (step S913).

  FIG. 8 is a flowchart showing a face detection processing procedure performed by the camera control circuit 160.

  It is determined whether face detection information is input from the face detection circuit 134 (step S920). If face detection information is not input from the face detection circuit 134, the process proceeds to step S922.

  On the other hand, if face detection information is input from the face detection circuit 134 (step S920), face detection information based on the input face detection information is output to the HI control circuit 180 (step S921).

  Subsequently, it is determined whether or not the selected face information is input from the HI control circuit 180 (step S922). If the selected face information is not input from the HI control circuit 180, the face detection process ends.

  On the other hand, if the selected face information is input from the HI control circuit 180 (step S922), the face image corresponding to the selected selected face information is used using (Expression 7) to (Expression 9). An appropriate focal length Z is calculated, and a predetermined range of values based on the calculated appropriate focal length Z is obtained (step S923).

  Subsequently, focal length information, which is information including the appropriate focal length Z obtained in step S923 and a predetermined range of values, is output to the HI control circuit 180 (step S924).

  FIG. 9 is a flowchart showing a processing procedure for displaying an appropriate focal length by the HI control circuit 180.

  It is determined whether any of the faces displayed in the display areas 321 to 324 of the face selection display area 320 is selected (step S930), and any of the faces displayed in the display areas 321 to 324 is determined. If NO is selected, the process of displaying an appropriate focal length is terminated.

  On the other hand, if any of the faces displayed in the display areas 321 to 324 is selected (step S930), it is determined whether focal length information is input from the camera control circuit 160 (step S931). .

  If the focal length information is not input from the camera control circuit 160 (step S931), the proper focal length display processing is terminated.

  If the focal length information is input from the camera control circuit 160 (step S931), the range included in the input focal length information is displayed on the focal length display bar 311 as an appropriate focal length 313 (step S932).

  FIG. 10 is a flowchart showing a zoom-up processing procedure by the camera control circuit 160.

  Each processing procedure shown in steps S940 to S944 is the same as each processing procedure in steps S920 to S924 shown in FIG.

  In step S944, after the focal length information is output to the HI control circuit 180, the focal length information is output to the lens driver 170 (step S945).

  When the focal length information is input to the lens driver 170, a predetermined lens that configures the optical system 110 so that the lens driver 170 has an appropriate focal length included in the focal length information based on the input focal length information. The motors 190 and 191 attached to the are controlled.

  Note that, after the focal length information is output to the lens driver 170 in step S945, the camera position is set so that the face of the subject corresponding to the selected face image is “centered on the screen. May be displayed on the display unit 300, and the control of the motors 190 and 191 may be started after the person's face becomes the center of the screen.

  In the present embodiment, when the current focal length 312 falls within the proper focal length 313 displayed on the focal length display bar 311, the face of the subject corresponding to the selected face image is displayed. The camera control process may be executed so as to obtain a photographing condition that allows proper photographing, and the photographing condition may be set. This camera control process is a control process that enables the face of the subject corresponding to the selected face image to be imaged under appropriate conditions, so that an appropriate exposure state for the face is obtained. Exposure control processing, lens control processing to control the lens so that the face is in focus, white balance processing to make the face have an appropriate skin color, color control processing to control hue, focus control, There are processes such as focal length control. These control processes can be executed and set based on the face detection information detected by the face detection circuit 134.

  Further, based on the face detection information detected by the face detection circuit 134, the distance between the person corresponding to the face detected by the face detection circuit 134 and the imaging apparatus 100 can be estimated.

  Furthermore, based on the estimated distance, among the plurality of faces corresponding to the plurality of face images displayed on the display unit 300, the same focus position of the zoom lens controlled to have an appropriate focal length The face 300 corresponding to the face within the depth of field may be displayed on the display unit 300 as being in focus. For example, among the face images displayed in the captured image display area 310, a face image corresponding to a face within the same depth of field as the focus position of the zoom lens controlled to have an appropriate focal length. Is shaded.

  Next, an example of correcting an appropriate focal length range according to sex will be described.

  When the face detection circuit 134 detects a human face included in an image signal subjected to camera image processing by the camera image signal processing circuit 133, the detected face feature is extracted and based on the extracted face feature To determine gender. Then, the face detection circuit 134 outputs face detection information including the determined gender to the camera control circuit 160.

  When calculating the appropriate focal length Z, the camera control circuit 160 determines the appropriate ratio A obtained by using (Equation 7) based on the gender included in the face detection information from the face detection circuit 134 according to the gender. to correct. For example, when taking a picture of a woman, it is considered that a beautiful picture can be taken if the face is taken to be relatively small. For this reason, a value A2 that is larger than the value of the appropriate ratio A is used as the value of the appropriate ratio.

  Next, an example of correcting an appropriate focal length according to the shooting mode will be described.

  For example, when the landscape & portrait mode is set in the image capturing apparatus 100, it is often desirable to capture the background as well as the person. Therefore, the face screen ratio (composition ratio) may be set to be smaller than normal. desirable.

  Therefore, when calculating the appropriate focal length Z, the camera control circuit 160 uses a value A3 that is larger than the value of the appropriate ratio A as the value of the appropriate ratio, as in the case of photographing a woman. In addition, for an appropriate focal length range, for example, a width of about 1.0 times that is a larger value than usual may be used in order to widen the range of selection by the photographer.

  As described above, according to the embodiment of the present invention, when a human face is photographed in the face detection mode, the human face image included in the photographed image display area 310 of the display unit 300 is selected as the face selection mode. Since they are displayed side by side in a predetermined size in the display area 320, the size of the bust shot of the person the photographer wants to photograph can be easily confirmed before photographing. Thereby, it is possible to quickly perform appropriate photographing according to the photographing situation and the photographer's preference. Further, it is possible to efficiently capture the face intended by the photographer. In addition, since the photographer can easily check the size of the bust shot of the person he wants to shoot before shooting, it is possible to prevent unintentional shooting by the photographer and to effectively use a storage area for storing digital data. Can be used.

  In addition, when there are a plurality of human faces included in the captured image display area 310 of the display unit 300, a plurality of face images are displayed side by side in a predetermined size in the face selection display area 320. Can be easily confirmed before shooting. As a result, when searching for the face of the person to be imaged from the images included in the captured image display area 310 of the display unit 300, the face of the person to be imaged is quickly referred to the face selection display area 320. Since it is possible to search, shooting can be performed quickly.

  When shooting a human face with the face detection mode set, if there is no composition that the photographer wants to shoot in the face images displayed in a predetermined size in the face selection display area 320 The face image is not selected using the non-select button 331. Thereby, it is possible to quickly perform appropriate photographing according to the photographing situation and the photographer's preference.

  In addition, in order to be able to distinguish the area of the face image selected from the face images displayed in the face selection display area 320 from other areas, the person who the photographer wants to shoot is displayed with face selection. Shooting can be performed while confirming the selected face image in the region 320. Thereby, imaging can be performed quickly.

  By the way, when photographing a human face, the composition is often changed according to the photographer's preference and background. For example, when shooting at a famous tourist attraction, it is often the case that a relatively large number of backgrounds are taken in.

  However, in the above-described conventional technology, when photographing a human face part included in the photographing range displayed on the display unit of the imaging device, the face part is appropriately zoomed to determine the face part. However, it was not possible to make changes appropriately and quickly according to the photographer's preference and background.

  That is, when photographing a person included in the photographing range, there has been a problem that appropriate photographing according to the photographer's preference and background cannot be performed quickly.

  On the other hand, according to the present embodiment, the focal length range in which the face of the subject person corresponding to the selected face image can be photographed with an appropriate size is set as the appropriate focal length 313. Since it is displayed on the distance display bar 311, the photographer can easily visually confirm the range of the focal length. This makes it possible to quickly and easily perform appropriate shooting according to the photographer's preference.

  The embodiment of the present invention is an example for embodying the present invention and has a corresponding relationship with the invention-specific matters in the claims as shown below, but is not limited thereto. However, various modifications can be made without departing from the scope of the present invention.

  That is, in claim 1, 8 or 14, the imaging means corresponds to the imaging element 120, for example. A display unit corresponds to the display unit 300, for example. A face detection unit corresponds to the face detection circuit 134, for example.

  In claim 1, 6, 8, 14 or 15, the face image extracting means corresponds to the HI control circuit 180, for example.

  In Claims 1 to 3, 5 to 8, 14 or 15, the display control means corresponds to the HI control circuit 180, for example.

  The photographed image display area corresponds to the photographed image display area 310, for example.

  In claim 2 or 14, the face image display area corresponds to, for example, the face selection display area 320.

  In Claim 3 or 8, the face image selection means corresponds to the switch 211, for example.

  In claim 4, the photographing condition setting means corresponds to the camera control circuit 160, for example.

  The focal length calculation means corresponds to the camera control circuit 160, for example.

  In claims 8 to 11, the focal length display control means corresponds to the HI control circuit 180, for example.

  In claim 9 or 11, the focal length display area corresponds to, for example, the focal length display bar 311.

  In claim 12, the gender determining means corresponds to the camera control circuit 160, for example.

  In claim 13, the photographing mode setting means corresponds to the operation unit 210, for example.

  In claim 14, the zoom lens corresponds to, for example, a zoom lens constituting the optical system 110. The zoom lens control means corresponds to the lens driver 170, for example.

  In claim 16 or claim 17, the face detection procedure corresponds to, for example, step S920. The face image extraction procedure corresponds to, for example, step S902. The display control procedure corresponds to step S903, for example.

  The processing procedure described in the embodiment of the present invention may be regarded as a method having a series of these procedures, and a program for causing a computer to execute these series of procedures or a recording medium storing the program May be taken as

It is a block diagram which shows the function structural example of the imaging device 100 in embodiment of this invention. 6 is a diagram showing an example of image display displayed on the display unit 300. FIG. 3 is a block diagram illustrating a functional configuration example of a camera signal processing circuit 130. FIG. FIG. 6 is a diagram showing an image display displayed in a captured image display area 310 and a face selection display area 320 of the display unit 300 and a face image of father H2 included in the captured image display area 310. It is a figure which shows the example of a display of the picked-up image display area 310 at the time of aligning the present focal distance 312 to the wide end side or tele end side of the range which the appropriate focal distance 313 displayed on the focal distance display bar 311 shows. . 6 is a flowchart showing a processing procedure for displaying a detected face image by an HI control circuit 180. 7 is a flowchart showing a face selection processing procedure by the HI control circuit 180. 6 is a flowchart illustrating a face detection processing procedure performed by a camera control circuit 160; 5 is a flowchart showing a processing procedure of an appropriate focal length display by an HI control circuit 180. 5 is a flowchart showing a zoom-up processing procedure performed by a camera control circuit 160.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Image pick-up device 110 Optical system 120 Image pick-up element 130 Camera signal processing circuit 131 I / F circuit 132 Detection circuit 133 Camera image signal processing circuit 134 Face detection circuit 135 Memory I / F circuit 136 I / F circuit 137, 138 Bus 140 Buffer memory 150 Image processing circuit 160 Camera control circuit 170 Lens driver 180 HI control circuit 190, 191 Motor 200 Exposure drive part 210 Operation part 211 Switch 300 Display part 310 Photographed image display area 311 Focal length display bar 312 Current focal length 313 Appropriate focal point Distance 320 Face selection display area 331 Non-selection button

Claims (17)

In an imaging apparatus including a display unit that displays an image captured by the imaging unit,
Face detection means for detecting a human face included in the image picked up by the image pickup means;
A face image extracting unit that extracts a face image corresponding to the face detected by the face detecting unit from an image captured by the imaging unit;
An image pickup apparatus comprising: a display control unit that causes the display unit to display the face image extracted by the face image extraction unit. At least a part of the display means is provided with a captured image display area and a face image display area,
The display control means displays an image picked up by the image pickup means in the photographed image display area and displays a face image extracted by the face image extraction means in the face image display area. Item 2. The imaging device according to Item 1. A face image selecting means for selecting the face image displayed on the display means;
The imaging apparatus according to claim 1, wherein the display control unit causes the display unit to display that the face image is selected by the face image selection unit.   The photographing condition setting means for setting the photographing condition for the face of the subject corresponding to the face image selected by the face image selecting means based on the face image extracted by the face image extracting means. Item 4. The imaging device according to Item 3.   The imaging apparatus according to claim 1, wherein the display control unit converts the face image extracted by the face image extraction unit into a predetermined size and displays the converted image on the display unit. The face image extraction means, when a plurality of faces are detected by the face detection means, extracts a plurality of face images corresponding to the detected plurality of faces from the image captured by the imaging means,
The imaging apparatus according to claim 5, wherein the display control unit causes the display unit to display a plurality of face images extracted by the face image extraction unit. At least a part of the display means is provided with a face image display area,
The imaging apparatus according to claim 6, wherein the display control unit displays a plurality of face images extracted by the face image extraction unit in a list in the face image display area according to a predetermined condition. In an imaging apparatus including a display unit that displays an image captured by the imaging unit,
Face detection means for detecting a human face included in the image picked up by the image pickup means;
A face image extracting unit that extracts a face image corresponding to the face detected by the face detecting unit from an image captured by the imaging unit;
Face image display control means for causing the display means to display the face image extracted by the face image extraction means;
Face image selection means for selecting a face image displayed on the display means;
An appropriate focal length, which is a focal length at which a face of a subject corresponding to the face image selected by the face image selection unit is captured by the imaging unit, has a predetermined composition ratio is set to a current focal length and the face image. A focal length calculating means for calculating based on the size of the face image extracted by the extracting means;
An imaging apparatus comprising: a focal length display control unit configured to display an appropriate focal length calculated by the focal length calculation unit on the display unit. At least a part of the display means is provided with a focal length display area for displaying the current focal length,
9. The imaging apparatus according to claim 8, wherein the focal distance display control means displays an appropriate focal distance calculated by the focal distance calculation means in the focal distance display area. The focal length calculation unit is a focal length indicating a certain range of a focal length in which an image of the face of the subject corresponding to the face image selected by the face image selection unit is captured by the imaging unit and having a predetermined composition ratio. A range is calculated based on the calculated appropriate focal length,
The imaging apparatus according to claim 9, wherein the focal length display control unit displays the focal length range calculated by the focal length calculation unit in the focal length display area. The focal length display area is a rod-shaped area where one end indicates the telephoto side and the other end indicates the wide-angle side,
The focal length display control means displays the current focal length by displaying a position corresponding to the value of the current focal length in a color different from other parts in the focal length display area and the focal length. 11. The imaging apparatus according to claim 10, wherein the focal length range is displayed by displaying a portion corresponding to the value of the focal length range calculated by the calculation means in a color different from that of the other portions. Gender discrimination means for discriminating the gender of a person related to the face based on a face image corresponding to the face detected by the face detection means;
The imaging apparatus according to claim 8, wherein the focal length calculation unit corrects the calculated proper focal length according to the determined gender. It further comprises a shooting mode setting means for setting a shooting mode which is a shooting condition for shooting the subject,
9. The imaging apparatus according to claim 8, wherein the focal length calculation unit corrects the calculated proper focal length in accordance with the set shooting mode. In an imaging apparatus including a display unit that displays an image captured by the imaging unit and a zoom lens,
Face detection means for detecting a human face included in the image picked up by the image pickup means;
A face image extracting unit that extracts a face image corresponding to the face detected by the face detecting unit from an image captured by the imaging unit;
Face image display control means for causing the display means to display the face image extracted by the face image extraction means;
Face image selection means for selecting a face image displayed in the display area;
An appropriate focal length, which is a focal length at which a face of a subject corresponding to the face image selected by the face image selection unit is captured by the imaging unit, has a predetermined composition ratio is set to a current focal length and the face image. A focal length calculating means for calculating based on the size of the face image extracted by the extracting means;
An image pickup apparatus comprising: a zoom lens control unit that controls the zoom lens based on an appropriate focal length calculated by the focal length calculation unit. The face image extraction means, when a plurality of faces are detected by the face detection means, extracts a plurality of face images corresponding to the detected plurality of faces from the image captured by the imaging means,
A plurality of face images extracted by the face image extracting means are displayed on the display means and controlled by the zoom lens control means among a plurality of faces corresponding to the plurality of face images displayed on the display means. And a display control means for displaying on the display means that the face image corresponding to the face within the same depth of field as the focus position of the zoom lens is in focus. The imaging device according to claim 14. In an image processing method used for an imaging apparatus including a display unit that displays an image captured by an imaging unit,
A face detection procedure for detecting a human face included in an image captured by the imaging means;
A face image extraction procedure for extracting a face image corresponding to the face detected in the face detection procedure from an image captured by the imaging means;
A display control procedure for causing the display means to display the face image extracted in the face image extraction procedure. In an imaging apparatus including a display unit that displays an image captured by the imaging unit,
A face detection procedure for detecting a human face included in an image captured by the imaging means;
A face image extraction procedure for extracting a face image corresponding to the face detected in the face detection procedure from an image captured by the imaging means;
A program for causing a computer to execute a display control procedure for causing the display means to display the face image extracted in the face image extraction procedure.

Images