JP2008182368A - Imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging device capable of appropriately adjusting the white balance of a picked-up image, thereby obtaining a picked-up image with a natural tone when flash light is emitted. <P>SOLUTION: When a flash device preliminarily emits light (S1), a subject is imaged and a picked-up image is generated (S2). A control unit detects a face area included in the generated picked-up image (S3) and then detects an area of eyes included in the face area (S4). Then the control unit detects an eye's white area included in the detected in the eye area (S5) and then detects color information on the eye's white area (S6) to compute an adjustment value of white balance based upon the detected color information (S7). Then the control unit makes the flash light primarily emit light (S8) to capture a subject and after a picked-up image is generated (S9), the calculated white balance adjustment value is used to adjust the white balance so that the eye's white area in the picked-up image is white (S10). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging apparatus, and more particularly to a white balance adjustment technique.

  In a conventional imaging device such as a digital camera, the skin area color information detected from the facial area in the captured image is compared with the skin color information recorded in advance, and as a result of this comparison, the skin in the captured image There is known a technique for adjusting the white balance of a captured image so that the color information of the image and the recorded skin color information substantially coincide. As such an imaging device, for example, an imaging device disclosed in Patent Document 1 is known.

  In general, the color of human skin varies depending on, for example, the race. In the above-described imaging apparatus, white balance adjustment of a captured image is performed based on skin color. Therefore, white balance adjustment may not be appropriately performed due to a difference in skin color due to a difference in race or the like. Therefore, there is a problem that the captured image has an unnatural color, and the same problem occurs in the captured image captured when the flash is emitted.

In Patent Document 2 and Patent Document 3, imaging is performed by calculating a white balance adjustment value by performing a predetermined calculation on the entire image data, and adjusting the white balance by auto white balance processing using the adjustment value. An apparatus is disclosed. However, since these imaging devices perform white balance adjustment without using reference color information in the captured image, there are cases where appropriate white balance adjustment cannot be performed, and the above problem cannot be solved. Patent Document 4 discloses an imaging apparatus that adjusts white balance based on differences in filter sensitivities of color filters. Since this imaging apparatus also performs white balance adjustment without using reference color information in the captured image, the above problem cannot be solved.
JP 2003-30647 A JP 2005-184508 A JP 2006-145629 A JP 2006-129449 A

  The present invention has been made to solve the above-described problems, and can appropriately adjust the white balance of a captured image, and can obtain a captured image with a natural color when a flash is emitted. An object is to provide an imaging device.

  In order to achieve the above object, the invention of claim 1 has an image pickup device that receives light from a subject and converts it into an electrical signal, picks up the subject and obtains a picked-up image, and a flash at the time of image pickup A flash unit that has a pre-emission function for obtaining a light emission amount, irradiates light on a subject, a recording unit that records a captured image captured by the imaging unit, and a captured image captured by the imaging unit And display means for displaying various messages, a shutter button operated by the user, an operation means having an operation button for giving an instruction to the apparatus, and color information based on a color temperature or the like of an arbitrary area in the captured image Color information detection means for detecting white balance adjustment values for calculating white balance adjustment values so that a white subject appears white in the captured image And a white balance adjustment unit that adjusts the white balance of the captured image using the white balance adjustment value obtained by the white balance adjustment value calculation unit, and a control unit that controls each unit of the apparatus. In the apparatus, a face area detecting means for detecting a face area included in the captured image, an eye area detecting means for detecting an eye area included in the face area detected by the face area detecting means, and the eye area White eye area detecting means for detecting a white eye area included in the eye area detected by the detecting means, and the control means is detected by the white eye area detecting means when the flash means is pre-flashed. The color information of the white-eye area in the captured image obtained from the imaging means is detected using the color information detection means, and the detected color information As a reference, the white balance adjustment value calculation means calculates the white balance adjustment value, and the flash balance means uses the white balance adjustment value calculated by the white balance adjustment value calculation means when main flashing is performed. Thus, the white balance adjustment means adjusts the white balance of the captured image so that the white-eye region in the captured image in the subsequent imaging is reflected in white.

  According to the second aspect of the present invention, there is provided an imaging unit that captures an image of a subject to obtain a captured image, a flash unit that has a pre-light emission function and irradiates the subject with light, and detects color information of an arbitrary area in the captured image. Color information detection means, white balance adjustment value calculation means for calculating a white balance adjustment value such that a white subject appears white in the captured image, and white balance adjustment obtained by the white balance adjustment value calculation means A facial area detection unit that detects a facial area included in a captured image in an imaging apparatus including a white balance adjustment unit that adjusts a white balance of a captured image using values and a control unit that controls each unit of the apparatus An eye area detecting means for detecting an eye area included in the face area detected by the face area detecting means, and the eye area detecting hand White eye area detecting means for detecting a white eye area included in the eye area detected by the control unit, and the control means detects the white eye area detecting means detected when the flash means pre-emits. Color information of a white-eye region in a captured image obtained from the imaging unit is detected using the color information detection unit, and the white balance adjustment value calculation unit calculates the white balance adjustment value based on the detected color information. When the flash unit performs a main light emission, the white balance adjustment unit uses the white balance adjustment value calculated by the white balance adjustment value calculation unit. The white balance of the captured image is adjusted so that the white eye region appears white.

  According to a third aspect of the present invention, in the imaging apparatus according to the second aspect, a recording unit for recording a captured image captured by the imaging unit, a captured image captured by the imaging unit, and various messages are displayed. Display means for doing this.

  According to the present invention, when the flash unit pre-flashes, the white balance adjustment value is calculated based on the color information of the white eye area in the captured image, and when the flash unit performs the main flash, the calculated white balance is calculated. The white balance of the captured image is adjusted using the adjustment value. Since the color of the white-eye region hardly varies depending on the race or the like, it is possible to appropriately adjust the white balance of the captured image when capturing with the flash means, and obtain a captured image with a natural hue be able to.

  Hereinafter, an imaging apparatus according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. 1A shows the front of the imaging device 1, FIG. 1B shows the back of the imaging device 1, and FIG. 2 shows the internal configuration of the imaging device 1. FIG. The imaging device 1 includes a flash device (flash unit) 11 that irradiates a subject with light so that imaging can be performed at night or indoors, an imaging unit (imaging unit) 12 for imaging the subject, and a captured image. And an LCD (display unit) 13 for displaying various messages, an operation unit 14 (operation unit) having buttons and the like for operating the imaging apparatus 1, and a memory (recording) for recording the captured image Means) 15 and a control unit (color information detecting means, white balance adjustment value calculating means, white balance adjusting means, control means, face area detecting means, eye area detecting means, white eye area detecting means) 16 for controlling each part of the apparatus, and Is provided.

  The flash device 11 has a pre-emission function for obtaining the flash emission amount during imaging. The operation unit 14 includes a shutter button 21 that is operated by the user, an operation button 22 that is operated by the user to give an instruction to the imaging apparatus 1, and a power button that switches the imaging apparatus 1 to an on / off state. 23.

  The imaging unit 12 is configured by a CCD (Charge Coupled Device), receives an image sensor 31 that receives light from a subject and converts it into an electrical signal, a lens 32 that focuses the light from the subject on the image sensor 31, and an image A shutter 33 that performs an open / close operation to control the amount of light incident on the element 31 and an analog front end unit 34 that performs an AD conversion process that converts an electrical signal transmitted from the image sensor 31 into a digital image signal. Have. The analog front end unit 34 further performs a process of transmitting a drive pulse to the image sensor 31, a CDS process for an electric signal output from the image sensor 31, and a gain adjustment process in order to drive the image sensor 31. Note that the image pickup device 31 is not limited to a CCD, and may be a CMOS (Complementary Metal Oxide Semiconductor).

  The control unit 16 functions as color information detection means, white balance adjustment value calculation means, white balance adjustment means, control means, face area detection means, eye area detection means, and white eye area detection means in the claims. The control unit 16 receives captured image data (hereinafter referred to as a captured image) that is a digital image signal from the imaging unit 12, and adjusts brightness / color difference signal processing, contour correction processing, and white balance for the captured image. Various image signal processing such as processing is performed, and the captured image after processing these image signals is output to the LCD 13, or the captured image and various data are recorded in the memory 15.

  Next, white balance adjustment processing in a captured image captured when the flash device 11 emits light will be described with reference to FIG. FIG. 3 shows the white balance adjustment processing procedure of the captured image when the flash device 11 emits light. Here, it is assumed that the pre-flash function of the flash device 11 is enabled.

  When the shutter button 21 is pressed by the user, the control unit 16 pre-flashes the flash device 11 (S1), the subject is imaged by the imaging unit 12, and a captured image is generated (S2). After detecting the face area of the subject included in the generated captured image (S3), the control unit 16 detects the eye area included in the detected face area (S4). In the process of S3, when a plurality of face areas are detected in the captured image, the control unit 16 detects only one arbitrary face area.

  After detecting the white eye region included in the eye region detected in S4 (S5), the control unit 16 detects color information of the detected white eye region (S6), and uses the detected color information as a reference. The white balance adjustment value is calculated (S7). Then, the control unit 16 causes the flash device 11 to emit light (S8), the subject is imaged by the imaging unit 12, and a captured image is generated (S9). Using the white balance adjustment value calculated in S7, the control unit 16 adjusts the white balance of the captured image so that the white eye region in the captured image appears white (S10). After performing this process, the control unit 16 records the captured image in the memory 15 and also records the white balance adjustment value calculated in S7 in the memory 15 (S11). The adjustment of the white balance of the captured image in the subsequent imaging using the flash device 11 can be performed using the white balance adjustment value recorded in the memory 15 in S11.

  Next, the detection processing of each area in S3 to S5 will be described with reference to FIG. FIG. 4 shows an example of a captured image captured by the imaging apparatus 1. In the captured image 4, reference numeral 41 indicates a subject, reference numeral 42 indicates a face area, reference numeral 43 indicates an eye area, and reference numeral 44 indicates a white eye area. As shown in FIG. 4, the control unit 16 can detect an accurate white eye region 44 by sequentially detecting the face region 42, the eye region 43, and the white eye region 44. Therefore, the color information of the white eye region 44 can be accurately detected, and the white balance of the captured image can be appropriately adjusted using this color information as a reference.

  As described above, according to the imaging device 1 according to the present embodiment, when the flash device 11 pre-flashes, the white balance adjustment value is calculated based on the color information of the white eye region in the captured image, and the flash device 11 When the apparatus 11 performs main light emission, the white balance of the captured image is adjusted using the calculated white balance adjustment value. Since the color of the white eye region hardly varies depending on the race or the like, when the subject is imaged using the flash device 11, the white balance adjustment value is determined based on the color information of the white eye region in the captured image. By calculating, it is possible to appropriately adjust the white balance of the captured image and obtain a captured image with a natural hue.

  In addition, since the imaging device 1 can record the white balance adjustment value calculated when the flash device 11 emits light in the memory 15, in the captured image in the next imaging using the flash device 11, Without performing the processes of S1 to S7 shown in FIG. 3, the white balance can be adjusted appropriately, a captured image with a natural hue can be obtained, and the white balance adjustment process of the captured image can be obtained. Can be done quickly.

  In the above example, the imaging apparatus 1 performs the white balance adjustment based on the color information of the white eye region. However, the white eye region cannot be detected because a person is not imaged as a subject. In this case, the control unit 16 determines the state of the reflected light from the subject and adjusts the white balance to an appropriate white balance, or the white balance in the case of performing imaging using the strobe light or the like in the memory 15 of the imaging device 1. The adjustment value is recorded, and the user performs processing for selecting appropriate white balance adjustment by operating the operation button, whereby a captured image with an appropriate hue can be obtained.

  In the above-described embodiment, an example in which the imaging apparatus 1 adjusts the white balance of a captured image with reference to a human white-eye area is not limited to this. For example, a white-eye area is included in the eye area. When an existing animal is photographed as a subject, the white balance may be adjusted based on an animal having a white eye region.

  In the imaging device 1 according to the above embodiment, the example in which the white balance adjustment value is calculated from the captured image captured when the flash device 11 pre-flashes is shown. However, the present invention is not limited thereto. The white balance adjustment value may be calculated when the apparatus 11 performs main light emission.

  In the imaging device 1 according to the above-described embodiment, the example in which the control unit 16 calculates the white balance adjustment value based on only the color information of the white-eye region is not limited thereto. Further, an arbitrary number of sensors (for example, illuminance detection sensors) that can detect the state of ambient light, etc. are further provided, and using the detection results detected by these sensors and the color information of the white eye region, The control unit may calculate a white balance adjustment value. In this case, further appropriate white balance adjustment can be performed, and a captured image with an appropriate hue can be obtained.

(A) And (b) is the front view and back view of an imaging device which concern on one Embodiment of this invention. The block diagram which shows the internal structure of the said imaging device. 6 is a flowchart showing white balance adjustment processing of a captured image when the flash device of the imaging apparatus emits light. Explanatory drawing which shows the white-eye area | region of the white balance adjustment process of the said imaging device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Imaging device 4 Captured image 11 Flash device (flash means)
12 Imaging unit (imaging means)
13 LCD (display means)
14 Operation part (operation means)
15 Memory (Recording means)
16 Control unit (color information detection means, white balance adjustment value calculation means, white balance adjustment means, control means, face area detection means, eye area detection means, white eye area detection means)
21 Shutter button 22 Operation button (operation means)
23 Power button 31 Image sensor 41 Subject 42 Face area 43 Eye area 44 White eye area

Claims (3)

An imaging device that receives light from a subject and converts the light into an electrical signal;
A flash unit that has a pre-emission function for obtaining a flash emission amount at the time of imaging;
A recording unit for recording a captured image captured by the imaging unit;
Display means for displaying captured images and various messages captured by the imaging means;
An operation unit having a shutter button operated by a user and an operation button for giving an instruction to the apparatus;
Color information detecting means for detecting color information based on a color temperature or the like of an arbitrary region in the captured image;
White balance adjustment value calculation means for calculating a white balance adjustment value so that a white subject appears white in the captured image;
White balance adjustment means for adjusting white balance of a captured image using the white balance adjustment value obtained by the white balance adjustment value calculation means;
In an imaging apparatus comprising a control means for controlling each part of the apparatus,
A face area detecting means for detecting a face area included in the captured image;
Eye area detecting means for detecting an eye area included in the face area detected by the face area detecting means;
White eye area detecting means for detecting a white eye area included in the eye area detected by the eye area detecting means;
The control means includes
When the flash unit pre-emits, the color information of the white eye region in the captured image obtained from the imaging unit detected by the white eye region detection unit is detected using the color information detection unit, and the detected color Using the information as a reference, the white balance adjustment value calculating means calculates the white balance adjustment value,
When the flash unit emits the main light, the white balance adjustment unit uses the white balance adjustment value calculated by the white balance adjustment value calculation unit, so that the white-eye region in the captured image in the next and subsequent imaging is white. An image pickup apparatus that adjusts the white balance of a picked-up image so as to appear in the image. Imaging means for capturing an image of a subject and obtaining a captured image;
A flash unit having a pre-flash function and irradiating the subject with light;
Color information detecting means for detecting color information of an arbitrary region in the captured image;
White balance adjustment value calculation means for calculating a white balance adjustment value so that a white subject appears white in the captured image;
White balance adjustment means for adjusting white balance of a captured image using the white balance adjustment value obtained by the white balance adjustment value calculation means;
In an imaging apparatus comprising a control means for controlling each part of the apparatus,
A face area detecting means for detecting a face area included in the captured image;
Eye area detecting means for detecting an eye area included in the face area detected by the face area detecting means;
White eye area detecting means for detecting a white eye area included in the eye area detected by the eye area detecting means;
The control means includes
When the flash unit pre-emits, the color information of the white eye region in the captured image obtained from the imaging unit detected by the white eye region detection unit is detected and detected using the color information detection unit. Based on color information, the white balance adjustment value calculating means calculates the white balance adjustment value,
When the flash unit performs main light emission, the white balance adjustment unit uses the white balance adjustment value calculated by the white balance adjustment value calculation unit, and the white-eye region in the captured image in the next and subsequent imaging is white. An image pickup apparatus that adjusts the white balance of a picked-up image so as to appear in the image. A recording unit for recording a captured image captured by the imaging unit;
The imaging apparatus according to claim 2, further comprising display means for displaying a captured image taken by the imaging means and various messages.

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