JP2015045771A - Digital camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To illuminate while emphasizing a main subject.SOLUTION: A digital camera 2 includes an imaging unit 12 that photographs subject light, an illumination unit 18 that emits illumination light illuminating the entire area in a photographic angle of view, a detection unit 4 that detects a main subject included in image data that is output from the imaging unit, and an illumination control unit 20 that adjusts the illumination light so that a predetermined area including the main subject becomes brighter than other areas than the predetermined area in the photographic angle of view.

Description

  The present invention relates to a digital camera that emits illumination light to photograph a subject.

  2. Description of the Related Art Conventionally, there has been known a moving image capturing apparatus that can adjust the light emission amount of an illumination device according to a change in brightness of a subject (see Patent Document 1).

JP 2005-354155 A

  However, in the above-described moving image pickup apparatus, since it is not possible to perform spot irradiation on a part of the area included in the shooting angle of view, it is impossible to emphasize and illuminate only the main subject.

  An object of the present invention is to provide a digital camera capable of highlighting and illuminating a main subject.

  The digital camera of the present invention includes an imaging unit that captures subject light, an illumination unit that emits illumination light that illuminates the entire area within the shooting angle of view, and a main subject included in image data output from the imaging unit. A detection unit for detecting, and an illumination control unit for adjusting the illumination light so that a predetermined region including the main subject is brighter than other regions other than the predetermined region within the shooting angle of view. It is characterized by.

  According to the digital camera of the present invention, the main subject can be emphasized and illuminated.

1 is a block diagram showing a configuration of a digital camera according to a first embodiment. It is a figure which shows the illumination part of the digital camera which concerns on 1st Embodiment. It is a figure which shows the area | region illuminated by the illumination part of the digital camera which concerns on 1st Embodiment. It is a flowchart which shows the moving image shooting process in the digital camera which concerns on 1st Embodiment. It is a block diagram which shows the structure of the digital camera which concerns on 2nd Embodiment. It is a figure which shows the structure of the slit of the digital camera which concerns on 2nd Embodiment. It is a figure which shows the structure of the slit of the digital camera which concerns on 2nd Embodiment. It is a flowchart which shows the moving image shooting process in the digital camera which concerns on 2nd Embodiment. It is a figure which shows the state which has arrange | positioned several LED in the front surface of the digital camera which concerns on embodiment.

  Hereinafter, a digital camera according to the first embodiment will be described with reference to the drawings. FIG. 1 is a block diagram showing a system configuration of the digital camera 2 according to the first embodiment. As illustrated in FIG. 1, the digital camera 2 includes a CPU 4. The CPU 4 includes an operation unit 10, an image sensor 12 that images subject light and generates an image signal, and an image based on the image signal from the image sensor 12. An LCD display unit 14 to be displayed, an illumination control unit 20 for controlling lighting and extinguishing of the illumination unit 18 and an emission amount of illumination light emitted from the illumination unit 18, a face recognition unit 22 for recognizing a human face from image data, and A memory card 24 for storing image data is connected.

  Here, the operation unit 10 includes a power switch (not shown) for turning on / off the power of the electronic camera 2, a moving image shooting button (not shown), and the like. The image sensor 12 is configured by a CMOS image sensor or the like. Here, the illumination unit 18 is disposed at a predetermined position on the front surface of the digital camera 2.

  FIG. 2 is a diagram of the illumination unit 18 viewed from the front (subject side). As shown in FIG. 2, the illumination unit 18 includes an LED 19a, an LED 19b, an LED 19c, an LED 19d, an LED 19e, and an LED 19f as light sources. Here, a case where six LEDs are arranged in the rectangular illumination unit 18 will be described as an example, but the shape of the illumination unit 18 and the number and positions of the LEDs arranged in the illumination unit 18 will be described. It is not limited to examples.

  Here, as shown in FIG. 3, the LED 19 a illuminates a region A displayed at the upper right of the LCD display unit 14 within the shooting angle of view. The LED 19b illuminates a region B displayed on the upper part of the LCD display unit 14 within the shooting angle of view, and the LED 19c illuminates a region C displayed on the upper left of the LCD display unit 14. Similarly, the LED 19d illuminates a region D displayed at the lower right of the LCD display unit 14, the LED 19e illuminates a region E displayed at the middle and lower part of the LCD display unit 14, and the LED 19f is illuminated by the LCD display unit 14. The area F displayed at the lower left of the screen is illuminated. In addition, the circle shown with a broken line has shown the illumination range illuminated with the illumination light inject | emitted from each LED, and it is within an imaging | photography angle of view by emitting illumination light from all LED contained in the illumination part 18. FIG. The entire area involved can be illuminated.

  Next, with reference to FIG. 4, the moving image shooting process in the digital camera 2 according to the first embodiment will be described. First, when the power is turned on, the CPU 4 starts imaging by the imaging device 12 and displays a through image on the LCD display unit 14 based on the imaging signal read from the imaging device 12 at a predetermined frame rate.

  The CPU 4 performs an exposure control operation (AE) and a focus adjustment operation (AF) when starting imaging. That is, the exposure control operation is performed based on the image pickup signal output from the image pickup device 12, and the shutter speed and the aperture value are determined so that proper exposure can be obtained. For example, when performing the exposure control operation by the multi-division photometry method, the subject area within the shooting angle of view is divided into a plurality of division areas, and a photometric value is detected for each division area. Then, the photometric value for each divided area is processed to determine the optimum exposure value, and the shutter speed and aperture value are determined. Further, the CPU 4 obtains a defocus amount by focus detection processing by pupil division using the focus detection signal read from the image sensor 12, and performs focusing of a photographing lens (not shown). Here, it is assumed that a focus detection pixel based on a pupil division phase difference method is incorporated in the CMOS image sensor constituting the imaging device 12.

  Next, when the moving image shooting button is operated, the CPU 4 starts moving image shooting processing (step S1). First, the illumination control unit 20 turns on all the LEDs included in the illumination unit 18 (step S2), and emits illumination light from all the LEDs. Thereby, illumination light is emitted toward the area corresponding to each LED, and the entire area included in the shooting angle of view is illuminated.

  Next, the CPU 4 starts continuous acquisition of image data based on the imaging signal output from the imaging element 12 in a state where the entire area included in the shooting angle of view is illuminated (step S3).

  Next, the CPU 4 performs a process of detecting a human face from the image data by the face recognition unit 22 (step S4). Here, when a human face is not detected from the image data, the CPU 4 continues to acquire the image data continuously in a state where the entire area included in the shooting angle of view is illuminated.

  On the other hand, when a person's face is detected from the image data, the CPU 4 limits the area illuminated by the illumination light to the area where the person's face exists (step S5), and the ISO set in the digital camera 2 The sensitivity is increased (step S6), and an exposure control operation (AE) and a focus adjustment operation (AF) are performed (step S7).

  That is, the CPU 4 specifies an area where the human face exists based on the position where the human face is detected from the image data. Next, the illumination control unit 20 maintains the light emission amount while turning on the LED that illuminates the area where the person's face exists, and turns off the LED that illuminates the area where the person's face does not exist ( Step S5).

  For example, when a person's face exists in the area A shown in FIG. 3, the illumination control unit 20 maintains the light emission amount while turning on only the LED 19a, and turns off the other LEDs. In addition, when a person's face exists in the area A and the area F illustrated in FIG. 3, the illumination control unit 20 maintains the light emission amount with the LEDs 19 a and 19 f on and turns off the other LEDs. Thereby, illumination light is emitted (hereinafter referred to as spot irradiation) limited to an area where a human face exists within the shooting angle of view.

  Further, the CPU 4 performs a process for increasing the ISO sensitivity set in the digital camera 2 (step S6). Here, the degree of increase in ISO sensitivity is determined so that the face portion of the person does not become overexposed and the portions other than the face of the person do not become blackened.

  Further, the CPU 4 performs an exposure control operation (AE) and also performs a focus adjustment operation (AF) so that the focus of the photographing lens matches the position of the person's face (step S7). When a plurality of human faces are detected, the focus is set on the face position designated by the operator.

  According to the digital camera 2 according to the first embodiment, when a human face is detected from the image data, the light emission amount is maintained while only the LEDs that illuminate the area where the human face exists are lit. In addition, since the LED that illuminates the area where no human face exists is turned off, the human face can be emphasized and illuminated.

  Next, processing of the digital camera according to the second embodiment will be described. The digital camera according to the second embodiment is provided with a single light source lamp in place of the plurality of LEDs of the first embodiment. Further, as shown in the block diagram of the digital camera 200 shown in FIG. 5, the slit control unit 34 is provided, and the slits arranged on the front surface of the light source lamp 30 are controlled by the slit control unit 34 so that the opening position and width of the slits are controlled. The range illuminated by the illumination light can be adjusted. Therefore, in the second embodiment, a detailed description of the same configuration as that of the first embodiment is omitted, and only different portions will be described. Further, the same components as those in the first embodiment will be described with the same reference numerals.

  6 and 7 are diagrams illustrating slits provided on the front surface of the light source lamp 30 of the digital camera 200 according to the second embodiment. As the slit, as shown in FIG. 6, a horizontal slit 32a forming a rectangular opening 33a extending in the left-right direction, or as shown in FIG. 7, a vertical opening forming a rectangular opening 36a extending in the up-down direction. A slit 32b is used.

  Here, as shown in FIG. 6, the horizontal slit 32 a blocks the upper slit 33 b that blocks the illumination light emitted to the upper portion within the shooting angle of view, and the illumination light emitted to the lower portion within the shooting angle of view. A lower slit 33c is provided. In this case, the CPU 4 uses the slit control unit 34 to move at least one of the upper slit 33b and the lower slit 33c in either the vertical direction, and adjusts the vertical position and width of the opening 33a.

  Further, as shown in FIG. 7, the vertical slit 32b is a left slit 36b that blocks illumination light emitted to the left side within the shooting field angle, and a right that blocks illumination light emitted to the right side within the shooting field angle. A slit 36c is provided. In this case, the CPU 4 uses the slit control unit 34 to move at least one of the left slit 36b and the right slit 36c in either the left or right direction, and adjusts the position and width of the opening 36a in the left / right direction.

  Next, with reference to FIG. 8, a moving image shooting process in the digital camera 200 according to the second embodiment will be described. When the moving image shooting button is operated in a state where the through image is displayed on the LCD display unit 14, the CPU 4 starts moving image shooting processing (step S11).

  First, the CPU 4 turns on the light source lamp 30 (step S12), and emits illumination light from the light source lamp 30. At this time, the width of the opening of the slit is adjusted to the maximum width. For this reason, the illumination light emitted from the light source lamp 30 is irradiated without being blocked by the slit, and the entire region included in the shooting angle of view is illuminated by the illumination light.

  Next, the CPU 4 starts continuous acquisition of image data based on the imaging signal output from the imaging element 12 in a state where the entire region included in the shooting angle of view is illuminated (step S13).

  Next, the CPU 4 performs a process of detecting a human face from the image data by the face recognition unit 22 (step S14). Here, when a human face is not detected from the image data, the CPU 4 continues to acquire the image data continuously in a state where the entire area included in the shooting angle of view is illuminated.

  On the other hand, when a person's face is detected from the image data, the CPU 4 limits the area illuminated by the illumination light to the area where the person's face exists (step S15), and the ISO set in the digital camera 2 The sensitivity is increased (step S16), and an exposure control operation (AE) and a focus adjustment operation (AF) are performed (step S17).

  That is, the CPU 4 specifies an area where the human face exists based on the position where the human face is detected from the image data. Next, the CPU 4 causes the slit controller 34 to move at least one of the upper slit 33b and the lower slit 33c in either the upper or lower direction, or to move at least one of the left slit 36b or the right slit 36c in either the left or right direction. The position and width of the opening 33a or the opening 36a are adjusted so that the illumination range illuminated by the illumination light is limited to a predetermined area including the face of the person (step S15).

  Further, the CPU 4 performs a process of increasing the ISO sensitivity set in the digital camera 2 (step S16). Here, the degree of increase in ISO sensitivity is determined so that the face portion of the person does not become overexposed and the portions other than the face of the person do not become blackened.

  Further, the CPU 4 performs an exposure control operation (AE) and also performs a focus adjustment operation (AF) so that the focus of the photographing lens matches the position of the person's face (step S17).

  According to the digital camera 200 according to the second embodiment, when a human face is detected from the image data, the range illuminated by the illumination light by the slit is limited to a predetermined range including the human face. Therefore, the person's face can be emphasized and illuminated.

  In the first embodiment described above, when a human face is detected from the image data, the illumination control unit 20 reduces the light emission amount of the LED that illuminates the area where the human face does not exist. May be. For example, when a human face exists at a position corresponding to the area A shown in FIG. 3, the CPU 4 maintains the light emission amount of the illumination light emitted from the LED 19a as it is and emits the illumination light emitted from the other LEDs. Reduce the amount.

  Next, the CPU 4 performs an exposure control operation (AE) and a focus adjustment operation (AF). For example, the optimum exposure value is determined so that the area where the person's face exists has an appropriate brightness, and the focus adjustment is performed so that the focus of the photographing lens matches the position of the person's face. As a result, when a moving image is captured while spot irradiating an area where a person's face exists, the portion of the person's face is not overexposed and the portion other than the person's face is prevented from being blacked out. it can.

  Further, in the first embodiment described above, the case where the illumination unit 18 having the plurality of LEDs 19a to 19f is provided on the front surface of the digital camera 2 has been described as an example. However, as illustrated in FIG. You may make it equip LED19a-19f in the predetermined position of the front surface of the digital camera 2, respectively.

  In the second embodiment described above, the horizontal slit 32a shown in FIG. 6 and the vertical slit 32b shown in FIG. 7 may be provided together. In this case, the CPU 4 causes the slit controller 34 to move at least one of the upper slit 33b and the lower slit 33c in either the upper or lower direction, and to move at least one of the left slit 36b or the right slit 36c in either the left or right direction. By moving it, the position and size of the opening can be freely adjusted.

  Further, in the above-described second embodiment, instead of the slit and the slit control unit 34, a direction control unit that can freely change the direction of the light source lamp 30, and a hood that covers the front periphery of the light source lamp 30, A hood adjustment unit that adjusts the angle of the hood (wide angle, narrow angle) may be provided. When a person's face is detected from the image data, the direction control unit adjusts the direction of the light source lamp 30 to the direction in which the person's face exists, and the hood adjustment unit adjusts the angle of the hood, thereby illuminating with illumination light. The range is limited to a range where a human face exists. Thereby, similarly to the case described in the first embodiment, it is possible to spot-irradiate an area where a human face exists.

  In this case, instead of the hood, the light source lamp 30 is provided with a light shielding portion that can adjust the amount of light passing by changing the opening diameter, and the opening diameter of the light shielding portion is changed. The irradiation range may be adjusted.

  Further, at the time of moving image shooting in each of the above-described embodiments, the face recognition process may be continuously performed by the face recognition unit 22, and the spot irradiation region may be changed in accordance with the change in the position of the person's face. Thereby, when a person moves, the person's face can be tracked and illuminated.

  In each of the above-described embodiments, a main subject recognition unit that recognizes a main subject from image data may be provided instead of the face recognition unit 22. In this case, the main subject recognition unit recognizes the main subject from the image data using a known main subject recognition technique at the time of moving image shooting. Therefore, moving image shooting can be performed while performing spot irradiation of illumination light on the main subject.

DESCRIPTION OF SYMBOLS 2,200 ... Digital camera, 4 ... CPU, 12 ... Image sensor, 14 ... LCD display part, 18 ... Illumination part, 19a-19f ... LED, 20 ... Illumination control part, 22 ... Face recognition part, 30 ... Light source lamp, 34 ... Slit controller

Claims (6)

An imaging unit for imaging subject light;
An illumination unit that emits illumination light that illuminates the entire area within the field of view;
A detection unit for detecting a main subject included in the image data output from the imaging unit;
A digital camera comprising: an illumination control unit that adjusts the illumination light so that a predetermined area including the main subject is brighter than other areas other than the predetermined area within the shooting angle of view; . The illumination unit includes a plurality of light sources,
The illumination control unit maintains a light emission amount of illumination light emitted from a light source that illuminates the predetermined area, and stops emission of illumination light from a light source that illuminates the other area,
Furthermore, a sensitivity control unit that increases the imaging sensitivity of the imaging unit by a predetermined amount;
The digital camera according to claim 1, further comprising an exposure control unit that determines an exposure value in a state where the photographing sensitivity is increased. The illumination unit includes a plurality of light sources,
The illumination control unit maintains a light emission amount of illumination light emitted from a light source that illuminates the predetermined region, and reduces a light emission amount of illumination light emitted from a light source that illuminates the other region,
The digital camera according to claim 1, further comprising an exposure control unit that determines an exposure value in a state where the light emission amount of the illumination light is reduced. The illumination unit includes a single light source,
The illumination control unit limits an illumination range of illumination light emitted from the light source to the predetermined region from the entire region within the shooting angle of view,
Furthermore, a sensitivity control unit that increases the imaging sensitivity of the imaging unit by a predetermined amount;
The digital camera according to claim 1, further comprising an exposure control unit that determines an exposure value in a state where the photographing sensitivity is increased.   The illumination control unit changes a light emission amount of the illumination light or an illumination range by the illumination light according to a change in a position of the main subject included in the image data. The digital camera according to any one of the above.   The digital camera according to claim 1, wherein the detection unit has a face recognition function.

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