JP2006186637A - Image generating apparatus and method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image formed by excluding a moving subject from a background. <P>SOLUTION: An image generating apparatus includes an imaging section which successively picks up a plurality of images having the same imaging range, a subject image acquisition section which makes the imaging section pick up the images according to an instruction input and acquires a subject image including a specified subject, a background image generation section which generates the background image of the specified subject on the basis of the plurality of images that the imaging section picks up within a designated time range including timing when the subject image acquisition section receives the indication input, a subject region image extraction section which extracts the subject region image of a region of the designated subject from the subject image that the subject image acquisition section acquires, and a composite image generation section which generates a composite image by combining the subject region image that the subject region image extraction section extracts with the background image that the background image generation section generates. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image generation device, an image generation method, and a program. In particular, the present invention relates to an image generation apparatus that generates an image, an image generation method, and a program for the image generation apparatus.

There is a technique of extracting a subject from an image captured by an imaging device and replacing the background of the extracted subject using a separately prepared background image (see, for example, Patent Document 1).
JP 2001-036801 A

  In some cases, tourists or the like who are not imaging targets appear in the background of an image captured at a sightseeing spot or the like, resulting in an unintentional image for the photographer. In this case, by extracting the imaging target from the image and replacing the extracted background of the imaging target with a separately prepared background image, the photographer obtains a composite image in which tourists and the like are not reflected in the background be able to. However, if the season, weather, etc. when a separately prepared background image is captured are different from the season, weather, etc., when the photographer actually captured, the resulting composite image will be less realistic. There was a problem that it would end up.

  SUMMARY An advantage of some aspects of the invention is that it provides an image generation apparatus and an image generation method capable of solving the above-described problems. This object is achieved by a combination of features described in the independent claims. The dependent claims define further advantageous specific examples of the present invention.

  An image generation apparatus according to a first aspect of the present invention includes an imaging unit that continuously captures a plurality of images having the same imaging range, and an object image that includes a specific subject by causing the imaging unit to capture an image based on an instruction input. And a background image that generates a background image of a specific subject based on a plurality of images captured by the imaging unit in a predetermined time range including a timing at which the subject image acquisition unit receives an instruction input. A subject area image extracting unit that extracts a subject area image of a specific subject area from the subject image acquired by the subject image acquiring unit, and a background image generated by the background image generating unit; A combined image generation unit that combines the extracted subject area images to generate a combined image;

  The background image generation unit may generate a background image by averaging a plurality of images captured by the imaging unit. The imaging unit includes a plurality of light receiving units that receive light of different colors for each of the plurality of pixels, the light receiving unit includes a plurality of light receiving elements having different light receiving areas, and the background image generation unit includes the imaging unit A background image may be generated by averaging the amount of received light for each of the plurality of captured images.

  The background image generation unit may generate a background image using a plurality of images captured by the imaging unit in a time range having a different width for each partial region of the background image. The background image generation unit may generate a background image of a partial area farther away from the specific subject in the composite image using a larger number of images captured by the imaging unit in a wider time range. Good. The background image generation unit generates a background image of the first partial region located in the vicinity of the specific subject in the composite image using a plurality of images captured by the imaging unit in the first time range, and specifies the background image in the composite image A background image of the second partial area located farther from the subject than the first partial area may be generated using a plurality of images captured by the imaging unit in the second time range including the first time range. .

  An image generation method according to a second aspect of the present invention includes a step of continuously capturing a plurality of images having the same imaging range by an imaging unit, and causing the imaging unit to capture an image based on an instruction input, including a specific subject. Acquiring a subject image, generating a background image of a specific subject based on a plurality of images captured by an imaging unit in a predetermined time range including a timing at which an instruction input is received, and specifying from the subject image Extracting a subject area image of the subject area, and synthesizing the subject area image with the background image to generate a composite image.

  According to the third aspect of the present invention, there is provided a program for an image generation apparatus that generates an image, the image generation apparatus for continuously capturing a plurality of images having the same imaging range, and an instruction input A subject image acquisition unit that acquires a subject image including a specific subject, and a plurality of images captured by the imaging unit in a predetermined time range including a timing at which the subject image acquisition unit receives an instruction input. A background image generation unit that generates a background image of a specific subject based on the image; a subject region image extraction unit that extracts a subject region image of a specific subject region from the subject image acquired by the subject image acquisition unit; and a background The subject region image extracted by the subject region image extraction unit is combined with the background image generated by the image generation unit to function as a composite image generation unit that generates a composite image.

  Note that the above summary of the invention does not enumerate all the necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.

  According to the present invention, it is possible to provide an image in which a moving subject is removed from the background.

  Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the claimed invention, and all combinations of features described in the embodiments are inventions. It is not always essential to the solution.

  FIG. 1 shows an example of a usage environment of an image generation apparatus 300 according to an embodiment of the present invention. The imager uses the image generation apparatus 300 to image the imager himself with the mountain as a background. The imager uses the user terminal 310 to instruct the image generation apparatus 300 to capture an image. The image generation apparatus 300 continuously captures a subject in a fixed imaging range, and extracts an image of the photographer from an image taken by the photographer when instructed to capture by the photographer. In addition, the image generation apparatus 300 uses a plurality of images captured during a period including the time when the imaging is instructed, and a landscape background in which a flying airplane, a moving person other than the photographer, etc. are not captured Generate an image. Then, the image generation apparatus 300 transmits a composite image obtained by superimposing the image of the photographer on the background image to the user terminal 310. In addition, the image generation apparatus 300 stores the composite image in a directory associated with the user terminal 310 in a server connected to the Internet or the like, and the photographer acquires the composite image from the server after capturing the image. May be.

  Note that the user terminal 310 and the image generation apparatus 300 may transmit and receive information instructing imaging, a composite image, and the like via infrared communication, or a communication line such as a wireless LAN or the Internet. The user terminal 310 may be a portable information terminal such as a mobile phone.

  According to the image generation apparatus 300 according to the present embodiment, an image in which only the photographer and the landscape are captured can be obtained. Furthermore, since the photographer can obtain an image having a landscape at the time close to the time when the imaging is instructed, a more realistic image can be obtained.

  FIG. 2 shows an example of a block configuration of an image generation apparatus 300 according to an embodiment of the present invention. The image generation apparatus 300 includes an imaging unit 200, an instruction input reception unit 202, a subject image acquisition unit 204, a subject area image extraction unit 206, a background image acquisition unit 208, a background image generation unit 210, and a composite image generation unit 212. Of the components included in the image generating apparatus 300, only the imaging unit 200 is installed at a location where a subject can be captured, and an instruction input receiving unit 202, a subject image acquiring unit 204, a subject region image extracting unit 206, and a background image acquiring unit. 208, the background image generation unit 210, and the composite image generation unit 212 may be realized by a personal computer or the like provided in a place different from the imaging unit 200.

  Hereinafter, operations of components included in the image generation apparatus 300 will be described. The imaging unit 200 continuously captures a plurality of images having a fixed imaging direction and angle of view and having the same imaging range. Specifically, the imaging unit 200 receives light from the subject with an imaging device such as a CCD and images the subject. Further, the imaging unit 200 continuously captures the subject at predetermined time intervals. The imaging unit 200 may hold a predetermined number of images obtained by continuously capturing images.

  The instruction input receiving unit 202 receives an instruction input indicating that imaging is instructed from the user terminal 310, and transmits the instruction input to the subject image acquisition unit 204. The subject image acquisition unit 204 causes the imaging unit 200 to capture an image based on the instruction input, and acquires a subject image. Note that the subject image acquisition unit 204 may use, as a subject image, an image captured by the imaging unit 200 at a timing closest to the timing at which an instruction input is received. The subject area image extraction unit 206 selects a person or the like as a specific subject from the subjects captured in the subject image acquired by the subject image acquisition unit 204, and the subject area image of the selected specific subject area. To extract.

  The background image acquisition unit 208 generates a background image of a specific subject from a plurality of images captured by the imaging unit 200 in a predetermined time range including a timing at which the subject image acquisition unit 204 receives an instruction input. Select an image to use. Then, the background image generation unit 210 generates a background image of a specific subject based on the plurality of images selected by the background image acquisition unit 208. Specifically, the background image generation unit 210 generates a background image by averaging a plurality of images captured by the imaging unit 200 for each pixel.

  The composite image generation unit 212 generates a composite image by combining the subject region image extracted by the subject region image extraction unit 206 with the background image generated by the background image generation unit 210. The composite image generated by the composite image generation unit 212 is transmitted to the user terminal 310. Thereby, it is possible to obtain an image in which a person or the like moving in the background is not reflected in the background of the specific subject.

  FIG. 3 shows an example of the configuration of the pixel 230 included in the imaging unit 200. FIG. 3A shows an example of the arrangement of the pixels 230. The pixel 230 includes a light receiving portion (242a to c, hereinafter collectively referred to as 242) that receives light of each color. The light receiving unit 242 includes a light receiving element (244a to c, hereinafter collectively referred to as 244), a light receiving element (246a to c, hereinafter collectively referred to as 246), and a filter (240a to c, hereinafter collectively referred to as 240). Is provided.

  FIG. 3B illustrates an example of the configuration of the light receiving element 244a, the light receiving element 246a, and the filter 240a included in the light receiving unit 242a. The filter 240a transmits light in the red wavelength band among the light from the subject. The light receiving element 246a and the light receiving element 244a receive light transmitted through the filter 240a. The light receiving element 244a and the light receiving element 246a may be light receiving elements such as photodiodes. The light receiving element 246a has a larger light receiving area and higher sensitivity than the light receiving element 244a.

  The light receiving unit 242b and the light receiving unit 242c have the same components as the light receiving unit 242a. Then, the light receiving unit 242b and the light receiving unit 242c are identified by adding the symbols b and c to the end of the codes of the respective structural elements of the light receiving unit 242c. The operations of the light receiving element 244 and the light receiving element 246 included in each of the light receiving unit 242b and the light receiving unit 242c are the same as the operations of the light receiving element 244a and the light receiving element 246a, respectively, and thus the description thereof is omitted. The filter 240b included in the light receiving unit 242b and the filter 240c included in the light receiving unit 242c transmit light in the green and blue wavelength bands, respectively.

  The background image generation unit 210 generates a background image by averaging a plurality of images captured by the imaging unit 200 for each color. Specifically, the background image generation unit 210 averages the amount of received light for each of the plurality of light receiving elements 244 and for each of the plurality of light receiving elements 246 for the plurality of images captured by the imaging unit 200. To generate a background image. For this reason, the amount of light received for each color of each pixel constituting the background image can be obtained with a wide dynamic range, so that the image quality of the background image can be improved.

  FIG. 4 shows an example of selecting an image to be used for generating a composite image. FIG. 5 shows an example of a procedure for generating a composite image using the image selected in FIG. The subject image acquisition unit 204 sets the image captured at the time closest to the imaging instruction time, which is the time when the instruction input is received from the instruction input reception unit 202, as the subject image. In the example of FIG. 4, an image captured at time t50 is a subject image 50. Note that the subject image acquisition unit 204 may use, as the subject image, an image obtained by causing the imaging unit 200 to capture an image at the imaging instruction time when the imaging unit 200 can capture an image at the imaging instruction time.

  The subject region image extraction unit 206 extracts a specific subject from the subject image 50 acquired by the subject image acquisition unit 204, and generates a subject region image 102 in which the extracted region of the specific subject is reflected. Specifically, the subject area image extraction unit 206 extracts a subject 520 located at the center of the subject image 50 as a specific subject by edge extraction or the like. The subject area image extraction unit 206 extracts the contours of a plurality of subjects from the subject image 50 by edge extraction or the like, and performs pattern matching between the extracted contours of the plurality of subjects and a predetermined person pattern. 510 and the person 520 may be extracted, and the person 510 having the largest area may be determined as a specific subject. In addition, the subject area image extraction unit 206 extracts a subject having a color close to the color of human skin from the subject image 50, and faces the front by pattern matching between the extracted subject and a predetermined face pattern. The person 510 and the person 520 having the faces that are present may be extracted, and either the person 510 or the person 520 having the face facing the front may be used as the specific subject.

  Further, the subject area image extraction unit 206 may determine a plurality of persons located in the vicinity of the specific subject, and set the whole of the plurality of persons as the specific subject. For example, when the person 510 is extracted as a specific subject, the person 520 in contact with the person 510 is extracted, and the person 510 and the person 520 are determined as specific subjects. In addition, the subject area image extraction unit 206 transmits the contours of a plurality of subjects obtained by edge extraction or the like to the user terminal 310 to cause the photographer to select a subject from the plurality of subjects, and the photographer selects A specific subject may be determined by receiving information such as the position of the subject. Further, the subject area image extraction unit 206 transmits the subject image 50 to the user terminal 310, causes the photographer to select the position of a specific subject, and receives information such as the position of the subject selected by the photographer. A specific subject may be determined.

  In the example of FIG. 5, the subject area image extraction unit 206 determines the person 510 and the person 520 from the subject image 50 as specific subjects. Then, the subject area image extraction unit 206 extracts the areas of the person 510 and the person 520 in the subject image 50 by edge extraction or the like, and generates the subject area image 102 in which only the person 512 and the person 522 are shown.

  The background image acquisition unit 208 generates a background image of a specific subject from a plurality of images captured by the imaging unit 200 in a predetermined time range including a timing at which the subject image acquisition unit 204 receives an instruction input. Select an image to use. In the example of FIG. 4, the background image acquisition unit 208 selects images (1 to 100) captured in a time range (t1 to t100) including an imaging instruction time that is a timing at which an instruction input is received. Then, the background image generation unit 210 generates the background image 104 by averaging the images (1 to 100) selected by the background image acquisition unit 208. Only the subject that is stationary in the time range (t1 to t100) is captured in the background image 104 obtained by averaging the plurality of images.

  For example, since the mountain shown as the image 544 of the image 1 in FIG. 8 hardly changes during the time range (t1 to t100), the image 546 of the image 100 is substantially the same as the image 544. Therefore, the mountain appears as the image 548 in the background image 104 obtained by averaging the images (1 to 100). On the other hand, the position of the airplane shown as the image 534 of the image 1 changes with time in the time range (t1 to t100), and moves to the position of the image 536 in the image 100. Therefore, almost no image of the flying airplane remains in the background image 104. Further, the person image 524 does not move during the time range (t1 to t100), and is substantially the same as the person image 526 in the image 100. Therefore, the person image 528 appears in the background image 104. Further, the person shown as the image 514 of the image 1 has one arm up during the time range (t1 to t100), and is shown as the image 516 in which the one arm is raised in the image 100. In this case, the person shown as the image 514 of the image 1 appears in the background image 104 as an image 518 in which the moving one arm has almost disappeared. In the background image 104, a fence behind the moving one arm is shown.

  The composite image generation unit 212 generates the composite image 106 by combining the subject region image 102 with the background image 104. In the example of FIG. 8, the composite image 106 is an image in which only two people, a mountain that is a landscape, and a fence are captured, and a flying airplane is not captured.

  FIG. 6 shows an example of setting the partial area of the background image. When selecting an image for generating a background image of a specific subject, the background image acquisition unit 208 sets a plurality of partial areas for the image and generates a background image for each partial area. The image to be used may be selected for each partial area. In the example of FIG. 6, the image is divided into five partial areas (120, 130, 140, 150, 160) in order from the vicinity of the specific subject. Of the partial areas (120, 130, 140, 150, 160), the partial area 120 is located closest to the specific subject, and the partial area 130, the partial area 140, the partial area 150, and the partial area 160 are: It is located farther than the partial area 120 from a specific subject. The background image acquisition unit 208 sets a range in which all of the specific subjects extracted from the plurality of background images selected by the background image acquisition unit 208 fall as the range of the partial region 120 located in the vicinity of the specific subject. It may be set. Each partial region is preferably set to the same region in a plurality of images selected by the background image acquisition unit 208.

  FIG. 7 shows an example of selecting an image used to generate a background image. FIG. 8 shows an example of a procedure for generating a composite image from the image selected in FIG. In the example of FIG. 7, the background image acquisition unit 208 displays the images (41 to 60) captured in the time range (t41 to t60) including the imaging instruction time, which is the timing at which the instruction input is received, in the vicinity of the subject. It selects as an image used in order to produce | generate the background image of the area | region 120. FIG. Then, the background image generation unit 210 generates the background image 122 in the partial region 120 by averaging the images (41 to 60) selected by the background image acquisition unit 208.

  The background image acquisition unit 208 also uses the background image of the partial area 120 as an image used to generate a background image in the partial area (130, 140, 150, 160) farther from the specific subject than the partial area 120. Is selected from a larger number of images (1 to 100) captured by the imaging unit 200 in a time range wider than the time range (t41 to t60) in which the images used to generate the image are captured. The background image acquisition unit 208 also uses images (41 to 41) used to generate the background image of the partial region 120 as images used to generate the background images of the partial regions (130, 140, 150, 160). 60) is selected.

  In the example of FIG. 7, images (11 to 90) captured by the imaging unit 200 in the time range (t11 to t90) are selected as images for generating the background image of the partial region 150. Further, as an image for generating the background image of the partial region 160, a larger number of images (1 to 100) captured by the imaging unit 200 in a wider time range (t1 to t100) are selected. Then, the background image generation unit 210 generates the background image 152 of the partial area 150 using the images (11 to 90), and generates the background image 162 of the partial area 160 using the images (1 to 100). Then, the background image generation unit 210 generates the background image 110 by synthesizing the background images in each of the partial regions (120, 130, 140, 150, 160).

  Note that the subject region image extraction unit 206 extracts a specific subject from the subject image 50 using a method similar to the method described in FIG. 5, and the subject region image 102 in which the extracted region of the specific subject is reflected. Is generated. Then, the composite image generation unit 212 generates the composite image 108 by combining the subject region image 102 extracted by the subject region image extraction unit 206 with the background image 110 generated by the background image generation unit 210.

  The background image generation unit 210 uses images (41 to 60) obtained by capturing the background images of the partial regions (120, 130, 140, 150, and 160) in the time range (t41 to t60) including the imaging timing. Therefore, an image close to the background at the actual imaging timing is obtained as the background image 110. In addition, the background image generation unit 210 averages a larger number of images obtained by the imaging unit 200 in a wider time range of a background image of a partial region farther from a specific subject in the composite image. Therefore, an object moving at a position away from a specific subject on the image is not shown in the composite image 108, and only the landscape can be left in the composite image 108. In addition, the background image generation unit 210 has a smaller number of images captured by the imaging unit 200 in a shorter time range in the partial region 120 near the subject than in the other partial regions (130, 140, 150, 160). Since the background image 122 is generated by averaging the images, an interesting image with movement can be obtained. In the example of FIG. 8, the arm moved by the person remains in the composite image 108 as an afterimage, and an image with a feeling of dynamism is obtained.

  FIG. 9 shows an example of a hardware configuration of a computer 1500 according to the present embodiment. The computer 1500 includes a CPU peripheral unit including a CPU 1505, a RAM 1520, a graphic controller 1575, and a display device 1580 connected to each other by a host controller 1582, and a communication interface 1530 connected to the host controller 1582 by an input / output controller 1584. An input / output unit having a hard disk drive 1540 and a CD-ROM drive 1560, and a legacy input / output unit having a ROM 1510, a flexible disk drive 1550, and an input / output chip 1570 connected to the input / output controller 1584.

  The host controller 1582 connects the RAM 1520, the CPU 1505 that accesses the RAM 1520 at a high transfer rate, and the graphic controller 1575. The CPU 1505 operates based on programs stored in the ROM 1510 and the RAM 1520 and controls each unit. The graphic controller 1575 acquires image data generated by the CPU 1505 and the like on a frame buffer provided in the RAM 1520 and displays the image data on the display device 1580. Alternatively, the graphic controller 1575 may include a frame buffer that stores image data generated by the CPU 1505 or the like.

  The input / output controller 1584 connects the host controller 1582 to the hard disk drive 1540, the communication interface 1530, and the CD-ROM drive 1560, which are relatively high-speed input / output devices. The hard disk drive 1540 stores programs and data used by the CPU 1505 in the computer 1500. The communication interface 1530 communicates with the image generation apparatus 300 via a network, and provides a program and data to the image generation apparatus 300. The CD-ROM drive 1560 reads a program or data from the CD-ROM 1595 and provides it to the hard disk drive 1540 and the communication interface 1530 via the RAM 1520.

  The input / output controller 1584 is connected to the ROM 1510, the flexible disk drive 1550, and the relatively low-speed input / output device of the input / output chip 1570. The ROM 1510 stores a boot program executed when the computer 1500 is started up, a program depending on the hardware of the computer 1500, and the like. The flexible disk drive 1550 reads a program or data from the flexible disk 1590 and provides it to the hard disk drive 1540 and the communication interface 1530 via the RAM 1520. The input / output chip 1570 connects various input / output devices via a flexible disk drive 1550 and, for example, a parallel port, a serial port, a keyboard port, a mouse port, and the like.

  A program provided to the communication interface 1530 via the RAM 1520 is stored in a recording medium such as the flexible disk 1590, the CD-ROM 1595, or an IC card and provided by the user. The program is read from the recording medium, provided to the communication interface 1530 via the RAM 1520, and transmitted to the image generation apparatus 300 via the network. The program transmitted to the image generation apparatus 300 is installed and executed in the image generation apparatus 300.

  A program that is installed and executed in the image generation apparatus 300 includes the image generation apparatus 300, the imaging unit 200, the instruction input reception unit 202, the subject image acquisition unit 204, the subject region image extraction unit 206, the background image acquisition unit 208, and the background. It functions as the image generation unit 210 and the composite image generation unit 212.

  The program shown above may be stored in an external storage medium. As the storage medium, in addition to the flexible disk 1590 and the CD-ROM 1595, an optical recording medium such as a DVD or PD, a magneto-optical recording medium such as an MD, a tape medium, a semiconductor memory such as an IC card, or the like can be used. Further, a storage device such as a hard disk or a RAM provided in a server system connected to a dedicated communication network or the Internet may be used as a recording medium, and the program may be provided to the computer 1500 via the network.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

2 is a diagram illustrating an example of a usage environment of an image generation device 300. FIG. 2 is a diagram illustrating an example of a block configuration of an image generation apparatus 300. FIG. 3 is a diagram illustrating an example of a configuration of a pixel included in an imaging unit 200. FIG. It is a figure which shows the example which selects the image for producing | generating a background image. It is a figure which shows an example of the procedure which produces | generates a synthesized image. It is a figure which shows an example of a partial area | region. It is a figure which shows the other example which selects the image for producing | generating a background image. It is a figure which shows an example of the other procedure which produces | generates a synthesized image. 2 is a diagram illustrating an example of a hardware configuration of a computer 1500. FIG.

Explanation of symbols

200 Image pickup unit 202 Instruction input reception unit 204 Subject image acquisition unit 206 Subject region image extraction unit 208 Background image acquisition unit 210 Background image generation unit 212 Composite image generation unit 230 Pixel 240 Filter 242 Light reception unit 244 Light reception element 246 Light reception element 300 Image generation Device 310 User terminal

Claims (8)

An imaging unit that continuously captures a plurality of images having the same imaging range;
A subject image acquisition unit configured to cause the imaging unit to capture an image based on an instruction input and acquire a subject image including a specific subject;
A background image generation unit that generates a background image of the specific subject based on a plurality of images captured by the imaging unit in a predetermined time range including a timing at which the subject image acquisition unit receives an instruction input;
A subject region image extraction unit that extracts a subject region image of the specific subject region from the subject image acquired by the subject image acquisition unit;
An image generation apparatus comprising: a composite image generation unit configured to combine the subject region image extracted by the subject region image extraction unit with the background image generated by the background image generation unit to generate a composite image. The image generation apparatus according to claim 1, wherein the background image generation unit generates the background image by averaging a plurality of images captured by the imaging unit. The imaging unit has a plurality of light receiving units for receiving light of different colors for each of a plurality of pixels,
The light receiving unit includes a plurality of light receiving elements having different light receiving areas,
The image generation apparatus according to claim 2, wherein the background image generation unit generates the background image by averaging a light reception amount for each of the light receiving elements with respect to a plurality of images captured by the imaging unit. The image generation apparatus according to claim 2, wherein the background image generation unit generates the background image using a plurality of images captured by the imaging unit in a time range having a different width for each partial region of the background image. The background image generation unit uses a larger number of images captured by the imaging unit in a wider time range of a background image of a partial area farther from the specific subject in the composite image. The image generation apparatus according to claim 4, which generates the image generation apparatus. The background image generation unit generates a background image of a first partial region located in the vicinity of the specific subject in the composite image using a plurality of images captured by the imaging unit in a first time range; A plurality of background images of the second partial region located farther from the first partial region than the specific subject in the composite image are captured by the imaging unit in a second time range including the first time range. The image generation apparatus according to claim 5, wherein the image generation apparatus is generated using an image. A step of continuously capturing a plurality of images having the same imaging range by an imaging unit;
Acquiring the subject image including a specific subject by causing the imaging unit to capture an image based on an instruction input;
Generating a background image of the specific subject based on a plurality of images captured by the imaging unit in a predetermined time range including a timing at which an instruction input is received;
Extracting a subject area image of the specific subject area from the subject image;
Combining the subject area image with the background image to generate a composite image. A program for an image generation device for generating an image, wherein the image generation device is
An imaging unit that continuously captures a plurality of images having the same imaging range;
A subject image acquisition unit that causes the imaging unit to capture an image based on an instruction input and acquires a subject image including a specific subject;
A background image generation unit that generates a background image of the specific subject based on a plurality of images captured by the imaging unit in a predetermined time range including a timing at which the subject image acquisition unit receives an instruction input;
A subject region image extraction unit that extracts a subject region image of the specific subject region from the subject image acquired by the subject image acquisition unit;
A program that functions as a composite image generation unit that generates a composite image by combining the subject region image extracted by the subject region image extraction unit with the background image generated by the background image generation unit.

Images