WO2011118134A1

WO2011118134A1 - Imaging device, image compositing method, and image compositing program

Info

Publication number: WO2011118134A1
Application number: PCT/JP2011/001227
Authority: WO
Inventors: 萩原強
Original assignee: パナソニック株式会社
Priority date: 2010-03-26
Filing date: 2011-03-02
Publication date: 2011-09-29
Also published as: JP2011205546A

Abstract

Disclosed is an imaging device which can minimize position offset of a subject, generate a composite image that is acceptable to a user, and also provide a composite image having exposure conditions that are acceptable to a user. In the imaging device, an imaging unit (103) alternately repeats overexposure and underexposure for each image, sets a different exposure value for each image, and captures a plurality of images. A memory (107) sequentially stores the images captured by the imaging unit (103). A dynamic range expanding and compositing processor (108) sequentially composites the images stored in the memory (107). A display unit (110) displays a composite image composited by the dynamic range expanding and compositing processor (108).

Description

Image capturing apparatus, image composition method, and image composition program

The present invention relates to a photographing apparatus, an image composition method, and an image composition program, and more particularly, to a photographing apparatus, an image composition method, and an image composition program that photograph and compose a plurality of images while changing exposure.

2. Description of the Related Art Conventionally, there is known a photographing apparatus that realizes expansion of a dynamic range and preferable gradation expression by combining a plurality of images with different photographing conditions (for example, Patent Document 1).

The imaging device of Patent Literature 1 includes a photometric unit that performs photometry of an object scene, a determination unit that determines a shooting condition that covers a range from a minimum value to a maximum value of a photometric value by the photometric unit by a plurality of shootings, And an imaging unit that generates a plurality of images by capturing the subject image a plurality of times in accordance with the imaging conditions. Then, n images taken by the photographing unit are recorded in the recording unit, and the recorded n images are appropriately combined. Thus, in Patent Document 1, it is possible to generate an image with an expanded dynamic range and preferable gradation expression.

Japanese Unexamined Patent Publication No. 2009-27622

However, in Patent Document 1, there is a problem that it is difficult to generate a composite image that can satisfy the user's satisfaction because the subject is misaligned when the interval between the shooting timings of the images to be combined is long. . Moreover, in patent document 1, when there are few variations of the exposure conditions in n images, there exists a problem that it is difficult to provide the composite image of the exposure conditions which can obtain a user's consent.

An object of the present invention is to provide a composite image with an exposure condition that can minimize the positional deviation of the subject, generate a composite image that satisfies the user's satisfaction, and can satisfy the user's satisfaction. It is to provide a photographing apparatus, an image composition method and an image composition program.

The imaging device of the present invention alternately repeats overexposure and underexposure for each image, sets a different variable exposure value for each image, and shoots a plurality of images, and shoots by the imaging unit A configuration is provided that includes storage means for sequentially storing images, combining means for sequentially combining the images stored in the storage means, and display means for displaying the combined image combined by the combining means.

The image composition method of the present invention is an image composition method in a photographing device that composes captured images, and alternately repeats overexposure and underexposure for each image and sets different variable exposure values for each image. The method includes a step of photographing a plurality of images, a step of sequentially storing the photographed images, and a step of sequentially synthesizing the stored images.

The image composition program according to the present invention includes a step of photographing a plurality of images by alternately repeating overexposure and underexposure for each image and setting different variable exposure values for each image on the computer. The step of sequentially storing the images and the step of sequentially combining the stored images are executed.

According to the present invention, it is possible to generate a composite image that can minimize the positional deviation of the subject and obtain the user's satisfaction, and to provide a composite image with an exposure condition that can satisfy the user's satisfaction. Can do.

The block diagram which shows the structure of the imaging device which concerns on embodiment of this invention The flowchart which shows the image composition method which concerns on embodiment of this invention The figure which shows the exposure setting method at the time of the imaging | photography by the continuous shooting which concerns on embodiment of this invention

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

(Embodiment)
FIG. 1 is a block diagram showing a configuration of a photographing apparatus 100 according to an embodiment of the present invention.

The photographing apparatus 100 includes an appropriate exposure determination unit 101, an exposure correction unit 102, a photographing unit 103, a pre-exposure correction value determination unit 104, a camera image capture control unit 105, a memory 106, a memory 107, and a dynamic It is mainly composed of a range expansion synthesis processing unit 108, a memory 109, and a display unit 110. In addition, the camera unit 150 that is an imaging unit includes an appropriate exposure determination unit 101, an exposure correction unit 102, and an imaging unit 103. Each configuration will be described in detail below.

The appropriate exposure determination unit 101 determines an appropriate exposure value and outputs the determined appropriate exposure value to the exposure correction unit 102.

The exposure correction unit 102 sets the exposure correction value input from the camera image capture control unit 105. Further, the exposure correction unit 102 sequentially changes the exposure at the time of shooting by continuous shooting in the shooting unit 103 for each image based on the set exposure correction value and the appropriate exposure value input from the appropriate exposure determination unit 101. Take control.

The imaging unit 103 repeats overexposure and underexposure alternately for each image according to the control of the exposure correction unit 102, and sets different exposure values for each image, thereby sequentially changing the exposure value to obtain a plurality of images. Take a picture. Further, the photographing unit 103 outputs the photographed image to the camera image capture control unit 105. Here, the overexposure means exposure that is equal to or higher than the appropriate exposure. Underexposure means exposure below the proper exposure.

The pre-exposure correction value determination unit 104 determines exposure correction values for the number of continuous shots. Then, the pre-exposure correction value determination unit 104 outputs the determined exposure correction value to the camera image capture control unit 105.

The camera image capture control unit 105 acquires the exposure correction value from the pre-exposure correction value determination unit 104 and outputs it to the exposure correction unit 102. The camera image capture control unit 105 captures an image captured by the capturing unit 103 and outputs the captured image to the memory 106 and the memory 107. At this time, the camera image capture control unit 105 captures an image photographed with appropriate exposure as preview image data 1g and outputs it to the memory 106.

The memory 106 stores the image input from the camera image capture control unit 105 as preview image data 1g.

The memory 107 sequentially stores a plurality of images input from the camera image capture control unit 105 as a dynamic range expansion composite image group 1i. The dynamic range expanding and synthesizing image group 1i stored in the memory 107 is managed in order of photographing time.

The dynamic range expansion / combination processing unit 108 performs a dynamic range expansion / combination process in which two images stored in the memory 107 are sequentially combined in time order. Then, the dynamic range expansion synthesis processing unit 108 outputs the composite image after the dynamic range expansion synthesis processing to the memory 109.

The memory 109 stores a plurality of composite images input from the dynamic range expansion composite processing unit 108 as a dynamic range expansion composite image group 1l.

The display unit 110 displays the image of the preview image data 1g stored in the memory 106 as a preview image. The display unit 110 displays each composite image of the dynamic range expanded composite image group 11 stored in the memory 109.

This completes the description of the configuration of the photographing apparatus 100.

Next, an image composition method in the photographing apparatus 100 will be described with reference to FIG. FIG. 2 is a flowchart showing an image composition method.

First, the pre-exposure correction value determination unit 104 determines the maximum exposure value for overexposure and the maximum exposure value for underexposure (step ST201). Further, the appropriate exposure determining unit 101 determines an appropriate exposure.

Further, the pre-exposure correction value determining unit 104 determines exposure correction values for the number of shots (N (N is an arbitrary natural number equal to or greater than 1) +1) based on the maximum exposure value determined in step ST201 ( Step ST202).

Next, the exposure correction unit 102 controls the exposure at the time of continuous shooting in the photographing unit 103 based on the exposure correction value and the appropriate exposure value determined in step ST202. The photographing unit 103 sets an exposure value according to the control of the exposure correction unit 102, and performs continuous shooting for the number of shots (step ST203).

Next, the dynamic range expansion / combination processing unit 108 performs N times of dynamic range expansion / combination processing for combining two images according to the order of time taken (step ST204).

This completes the description of the image composition method in the photographing apparatus 100.

Next, an exposure setting method for continuous shooting will be described with reference to FIG. FIG. 3 is a diagram illustrating an exposure setting method for continuous shooting.

In FIG. 3, the number of shots by continuous shooting is six. In FIG. 3, the average exposure value 3c is assumed to be 0 EV (Exposure Value). Further, in FIG. 3, in the range between the maximum overexposure value 3a (+2 EV) and the maximum underexposure value 3b (−2 EV) (range of −2 EV to +2 EV), the exposure is performed in steps of two thirds. Set the value to correct the exposure. Then, odd-numbered captured images are overexposed, even-numbered captured images are underexposed, and overexposure and underexposure are alternately repeated. Here, the average exposure value 3 c is a proper exposure value determined by the proper exposure determination unit 101. The maximum exposure value 3a and the maximum exposure value 3b are set in the exposure correction unit 102.

Also, when determining the exposure value of the first image to the (N + 1) th image during continuous shooting, the odd number of images at the top of the first image has the maximum exposure value of the first image. The exposure value is set to 3a, and thereafter, the exposure value is decreased so as to approach the average exposure value 3c as the number of the third and fifth images increases. Similarly, the exposure number of the second sheet is set to the maximum exposure value 3b of the underexposure, and the average exposure value 3c is increased as the number of sheets increases from the fourth sheet to the sixth sheet. Increase the exposure value to get closer. As a result, the first exposure value to the (N + 1) th exposure value during continuous shooting are set repeatedly alternately between the over exposure value and the under exposure value, while changing the zigzag. As the number increases, the average exposure value 3c approaches. In FIG. 3, the odd-numbered sheets are set to the over side and the even-numbered sheets are set to the under side. However, the present invention is not limited to this, and the odd-numbered sheets may be set to the under side and the even-numbered sheets are set to the over side.

Specifically, in FIG. 3, the maximum exposure value 3a for overexposure is + 2EV, and the maximum exposure value 3b for underexposure is −2EV. The odd number is the first, the third and the fifth, the exposure value of the first sheet is +2 EV, the exposure value of the third sheet is +4/3 EV, the exposure value of the fifth sheet is +2/3 EV, As the number increases, the average exposure value 3c is decreased. That is, the difference between the average exposure value 3c and the exposure value set in the photographing unit 103 increases as the image is photographed at a timing closer to the photographing start timing at the time of continuous shooting.

On the other hand, the even number is the second sheet, the fourth sheet, and the sixth sheet, the exposure value of the second sheet is −2 EV, the exposure value of the fourth sheet is −4/3 EV, and the exposure value of the sixth sheet is − It becomes 2/3 EV, and it increases so as to approach the average exposure value 3c as the number of sheets increases. That is, the difference between the average exposure value 3c and the exposure value set in the photographing unit 103 increases as the image is photographed at a timing closer to the photographing start timing at the time of continuous shooting.

As a result, the change in the exposure value of the first to sixth sheets during continuous shooting is “+2 EV”, “−2 EV”, “+4/3 EV”, “−4/3 EV”, “+2/3 EV”, “ -2 / 3EV ". That is, the zigzag change in which the overexposure exposure value and the underexposure exposure value are alternately set approaches the average exposure value 3c.

Further, the pre-exposure correction value determination unit 104 stores the exposure value set in the composite image shooting unit 103 selected by the user, determines the exposure correction value based on the stored exposure value, and uses the determined exposure correction value. Alternatively, an exposure value of a newly continuously shot image may be set. For example, the pre-exposure correction value determination unit 104 may change the exposure value set in the photographing unit 103 with a fixed correction amount other than 2/3 EV, or may shoot with a different correction amount for each continuously shot image. The exposure value set in the unit 103 may be changed.

As described above, according to the present embodiment, two images that are successively photographed and having different exposure conditions are combined, so that the positional deviation of the subject can be minimized, and the combination that satisfies the user can be obtained. An image can be generated. In addition, according to the present embodiment, since the exposure conditions are made different in all the images, variations of the exposure conditions can be increased, and a composite image of the exposure conditions that can satisfy the user can be provided.

In FIG. 3 of the present embodiment, the exposure value to be set is set to the EV value. However, the present invention is not limited to this, and for example, the exposure is set by a unique exposure correction parameter defined in the camera unit 150. Also good. That is, in the present embodiment, any parameter that can set different exposure values equal to or greater than the number of shots can be used. Further, in FIG. 3 of the present embodiment, an exposure value is set such that the difference from the average exposure value 3c is set for an image shot at a timing closer to the shooting start timing at the time of continuous shooting. However, the present invention is not limited to this. Instead, an exposure value may be set such that the difference between the average exposure value 3c and the image captured at a timing closer to the imaging start timing at the time of continuous shooting is smaller. In addition, an arbitrary exposure value may be set for each continuously shot image. In the present embodiment, the imaging device includes a camera-equipped communication terminal device such as a camera-equipped mobile phone.

The disclosure of the specification, drawings and abstract contained in the Japanese application of Japanese Patent Application No. 2010-72718 filed on March 26, 2010 is incorporated herein by reference.

The photographing apparatus, the image composition method, and the image composition program according to the present invention are particularly suitable for photographing and combining a plurality of images while changing the exposure.

DESCRIPTION OF SYMBOLS 100 Image pick-up apparatus 101 Proper exposure determination part 102 Exposure correction part 103 Image | photographing part 104 Preexposure correction value determination part 105 Camera image taking-in control part 106,107,109 Memory 108 Dynamic range expansion synthesis process part 110 Display part 150 Camera part

Claims

An imaging unit that alternately repeats overexposure and underexposure for each image and sets a different variable exposure value for each image, and shoots a plurality of images,
Storage means for sequentially storing images taken by the photographing means;
Combining means for sequentially combining the images stored in the storage means;
Display means for displaying a composite image synthesized by the synthesis means;
An imaging apparatus comprising:
The photographing apparatus according to claim 1, wherein the photographing unit sets the variable exposure value such that the difference from the appropriate exposure value increases as the image is photographed at a timing closer to the timing at which the photographing of the plurality of images is started.
The photographing apparatus according to claim 1, wherein the photographing unit sets the variable exposure value such that a difference from the appropriate exposure value is smaller as the image is photographed at a timing closer to the timing at which the photographing of the plurality of images is started.
The photographing apparatus according to claim 1, wherein the photographing unit sets the variable exposure value of the plurality of images to be newly photographed based on the variable exposure value of the composite image selected in the past.
2. The photographing apparatus according to claim 1, wherein the photographing unit photographs the plurality of images by continuous shooting.
An image composition method in a photographing apparatus for compositing captured images,
Repeating overexposure and underexposure alternately for each image, setting a different variable exposure value for each image, and taking a plurality of images,
Sequentially storing the captured images;
Sequentially combining the stored images;
An image composition method comprising:
On the computer,
Repeating overexposure and underexposure alternately for each image, setting a different variable exposure value for each image, and taking a plurality of images,
Sequentially storing the captured images;
Sequentially combining the stored images;
An image compositing program that executes