JP2001285762A - Image printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image printer capable of printing the clear image of an object by accurately extracting the area of the object even when the conditions of illumination and a background, etc., are changed. SOLUTION: A projector 1 projects projection pattern light 1a to a human body P. First and second cameras 3A and 3B pickup the image of reflected light 1b reflected on the side of the human body P and a processing part 4 prepares a luminance image and a distance image on the basis of video signals from the first and second cameras 3A and 3B. An image extraction part 7 extracts the image area of the human body P from the luminance image on the basis of the distance image and prepares printing data. A printing part 10 performs printing based on the printing data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image printing apparatus for imaging and printing a subject such as a person, and more particularly, to accurately extract a subject area even when conditions such as illumination and background change. The present invention relates to an image printing apparatus capable of printing a clear image of a subject.

[0002]

2. Description of the Related Art In recent years, a photographic printing apparatus as an image printing apparatus for taking an image of a person and printing it as one sticker composed of a plurality of photographs has been known as a very popular apparatus.

As such a conventional image printing apparatus, for example, Japanese Patent Application Laid-Open No. 10-336577 and Japanese Patent Application Laid-Open
There is one disclosed in Japanese Patent Application Laid-Open No. 0-243387.

An image printing apparatus disclosed in Japanese Patent Application Laid-Open No. H10-336577 has a camera section for capturing an image of a person, a current image storage section for storing a current image obtained by the camera section, and a background image stored in advance. A background image storage section for storing, a difference processing section for obtaining an absolute value of a difference of each pixel between the current image and the background image to form a difference image, and extracting a portion of the difference image having a predetermined value or more as a person area A person region extracting unit, a luminance distribution creating unit that creates a luminance distribution of only pixels included in the person region in the current image, a correction coefficient creating unit that determines a correction coefficient from the luminance distribution, and a person region using the correction coefficient. An image correction unit that corrects the current image so that the range of the luminance value of the image (person image) is maximized, a frame image storage unit that stores the frame image, and the current image and the frame image corrected by the image correction unit Synthesize A combining unit for forming a One of the composite image, and a printing unit for printing a plurality of synthesized images on one seal. This eliminates the necessity of installing a banner, enclosure, or the like for maintaining the background at a constant luminance, and can reduce the installation area of the device. In addition, the range of the luminance value of the person image can be enlarged to sharpen the person image.

The image printing apparatus disclosed in Japanese Patent Application Laid-Open No. H10-24387 is installed in a predetermined relative positional relationship with an infrared irradiating apparatus that irradiates an infrared ray to a person, and detects only infrared rays among reflected light from the person. A first digital camera for imaging, and a normal second digital camera for imaging reflected light from a person, and a storage unit for storing various types of background information,
The outline of the person is extracted based on the imaging information from the first digital camera, the person image is extracted from the image captured by the second digital camera using the outline of the person, and the person image and the background information selected from the storage unit are extracted. And a control unit for synthesizing and outputting the result to a printer. This eliminates the necessity of installing a banner, enclosure, or the like for maintaining the background at a constant luminance, and can reduce the installation area of the device. In addition, the amount of reflected light from infrared rays from a person is larger than that from a background,
By discriminating the imaging information from the digital camera based on an appropriate threshold value, the outline of the person can be identified, and the background combined with the person image can be freely changed.

[0006]

However, according to the conventional image printing apparatus, it is assumed that a stored background image and a background image obtained by imaging a person have substantially the same luminance. Therefore, when the luminances of the two are different, accurate extraction of the person area cannot be performed, and therefore, there is a problem that a clear image of the person cannot be obtained. For example, when the sun changes, the shadow of a person from the flash falls on the background, or when a person passes behind the person,
It cannot be extracted exactly.

Accordingly, an object of the present invention is to provide an image processing apparatus capable of accurately extracting an area of a subject even when conditions such as illumination and background change, thereby printing a clear image of the subject. A printing device is provided.

[0008]

In order to achieve the above object, the present invention provides an image pickup means for picking up an image of a background and a subject as an image pickup object to obtain a luminance image, and a measuring means for measuring a distance to the image pickup object. Extracting means for extracting a subject image from the luminance image based on the distance, forming means for forming print data based on the subject image, and printing means for performing printing based on the print data. An image printing apparatus is provided. According to the above configuration, the subject image can be accurately extracted by extracting the subject image from the brightness image based on the distance.

[0009]

FIG. 1 shows an image printing apparatus according to a first embodiment of the present invention. The image printing apparatus includes a projector 1 that projects a projection pattern light 1a coded with respect to intensity onto a person P as a subject, a half mirror 2 provided on an optical path of the projection pattern light 1a, and a projector 1
A first camera 3A that is provided coaxially with the optical axis of the first mirror 3 and captures the reflected light 1b reflected by the half mirror 2, and a direction different from the optical axis direction of the projector 1 by reflecting the reflected light 1b reflected by the person P side. A second camera 3B for capturing images from the first and second cameras 3B
A processing unit 4 for acquiring a distance image and a luminance image based on imaging signals from the cameras 3A and 3B, a distance image memory 5 for storing a distance image, a luminance image memory 6 for storing a luminance image, The image processing apparatus includes an image extracting unit 7 that inputs a luminance image and extracts a human image from the luminance image to form print data, and a printing unit 10 that prints print data output from the image extracting unit 7. The processing unit 4, the distance image memory 5, the luminance image memory 6, and the image extracting unit 7
The image control unit 8 extracts an image of the person P captured by the first camera 3A and the second camera 3B and performs print control.

The light projector 1 is configured to project a projection pattern light 1a composed of laser light in an invisible region of ultraviolet light or infrared light.

FIG. 2 shows a first camera 3A and a second camera 3B. The first camera 3A and the second camera 3B have a zoom function and a focusing function. The first camera 3A and the second camera 3B divide the reflected light 1b from the person P in two directions, and the prism 30 divides the reflected light 1b in one direction. Invisible region cutoff filter 31 that blocks components in the invisible region and transmits components in the visible region of reflected light 1b
A distance image CCD camera 32 for imaging the reflected light 1b transmitted through the invisible region cutoff filter 31; and an invisible region transmission filter that blocks the visible region component of the reflected light 1b and transmits only the invisible region component. 33, and a luminance image CCD camera 34 for imaging the reflected light 1b transmitted through the invisible region transmission filter 33.

The processing unit 4 inputs an imaging pattern obtained by imaging the reflected light 1b of the projection pattern light 1a projected from the light projector 1 by the distance image CCD camera 32 of the first camera 3A. This imaging pattern is compared with the projection pattern (slit pattern) in the processing unit 4 to compare the intensity difference. The comparison of the intensity difference is, for example,
This is performed by decomposing the slit pattern and the imaging pattern into cells of several pixels and comparing the average intensities of the cells. When the intensity difference is equal to or greater than the threshold value and has a new intensity, a re-encoding unit (not shown) generates and assigns a new-intensity code to re-encode the cell. . When the strength is not a new strength, a code of the corresponding strength is assigned to re-code the cell.

The image extraction unit 7 includes a distance image acquisition unit 12A
And a brightness area extraction unit 12B. Range image acquisition unit 1
2A, a threshold value processing unit 13 that determines a distance value in each pixel of the distance image based on the threshold value and extracts the distance value as a binary distance image, and a threshold value that stores a threshold value used for determining the distance. A value information memory 14 and an interpolation processing unit 1 for performing an interpolation process for removing noise included in acquiring a distance image
5 is provided. When the binary distance image acquired by the distance image acquiring unit 12A is input, the luminance area extracting unit 12B extracts a luminance image area having a pixel value of 1 from the luminance image stored in the luminance image memory 6 and prints the image. Printing unit 1 as data
0 is output.

Next, the operation of the image printing apparatus according to the present embodiment will be described with reference to the drawings.

In the following operation, a distance image of the person P is obtained based on the pattern projection method. First, the operator adjusts the camera angle so that the person P falls within the image-capable range of the first camera 3A and the second camera 3B, and projects the projection pattern light 1a from the projector 1 onto the person P. The first and second cameras 3A and 3B image the reflected light 1b reflected on the person P side and output an image signal to the processing unit 4. The processing unit 4 obtains a distance image and a luminance image by performing image processing on imaging signals from the first camera 3A and the second camera 3B. The procedure for measuring the distance by the pattern projection method will be described below.

FIG. 3 shows a distance measuring method based on the pattern projection method. The projector 1 projects the vertical stripe pattern light as the projection pattern light 1a onto the person P, and images the person P with the first camera 3A and the second camera 3B. The processing unit 4 extracts a stripe pattern from an imaging pattern input from an imaging signal from the range image CCD camera 32 of the first camera 3A, divides each stripe into cells of several pixels, and performs recoding (not shown). The code of each cell is detected using the code re-coded by the unit, and the slit angle θ from the light projector 1 is calculated based on the detected code. The slit angle θ of the cell to which each pixel belongs and the second
From the x coordinate on the image captured on the image plane of the CCD camera 32 for distance image of the camera 3B, the focal length F and the base line length (distance) L, which are camera parameters, by the following equation (1). The distance Z to A is calculated. Z = (F × L) / (x + F × tan θ) (1)

FIG. 4 shows an example of a luminance image when a person P is imaged. In the figure, Pa is a person image,
B is a background image and C is a display device image. An image obtained by capturing the human image P, the background image B, and the display device image C with the CCD camera for luminance image of the first camera 3A is stored in the luminance image memory 6 as a luminance image. This luminance image is obtained by classifying the luminance of light entering the light receiving portion of the first camera 3A from the surface of the person P for each pixel.

FIG. 5 shows an example of a distance image when the person P is imaged. The processing unit 4 determines the distance based on the amount of deformation of the projection pattern based on capturing the reflected light 1b of the projection pattern light 8a projected on the background and the person P by the distance image CCD camera 32 of the second camera 3B. The images are classified into regions, and a distance image is formed by assigning a distance code to pixels in each of the classified regions. This distance image is
The distance from the light receiving section of the camera 3B to each point of the object is defined as each pixel value, and is arranged two-dimensionally. In the drawing, the person image Pa is located at the forefront in the paper direction, an area 19 corresponding to C shown in FIG. 4 is located behind the image Pa, an area 16 is located further behind, and an area 16 is located further behind. 17 is located, and the area 18 is located at the rearmost position. As a method of displaying these on the screen, for example, the brightness can be expressed by the magnitude of the brightness, and the brightness may be increased in the area on the near side of the paper and decreased in the depth direction of the paper.

FIG. 6 shows a person image Pa based on the distance image.
And an image in which the other background portion 20 is separated, wherein the pixel value of the portion of the human image Pa is 1 (white), and the other background portion 2
The pixel value of 0 is displayed as 0 (black). When noise or the like is superimposed when acquiring a distance image, a pixel that should be 1 in the distance image may become 0 in some cases. In the figure, a dot 21 having a pixel value of 0 due to noise is formed in the portion of the human image Pa.

FIG. 7 shows a distance image on which interpolation processing has been performed by the interpolation processing section 15. When a 0 pixel on which noise is superimposed in a portion of the human image Pa is surrounded by 1 pixel, By performing the interpolation process of converting the 0 pixel into 1 to generate binary image data in which a defective pixel due to noise or the like included in the portion of the human image Pa is interpolated.

FIG. 8 shows print data in which a part of the human image Pa is extracted and the others are formed as a background having a pixel value of 0. The luminance area extracting unit 12B performs the following processing on the luminance image stored in the luminance image memory 6. A region having a pixel value of 1 in the binary image data input from the interpolation processing unit 15 of the distance image acquisition unit 12A, that is, a region corresponding to the portion of the human image Pa is extracted, and the other portions are defined as a background having a pixel value of 0. The print data is formed. The printing unit 10 prints on paper based on the print data.

According to the image printing apparatus of the first embodiment, the projection pattern light 1a projected on the person P is captured by the first and second cameras 3A and 3B based on the distance image obtained. Since the image area of the person P is extracted from the luminance image, an image of only the person P can be printed. Further, since no special equipment or operation is required, usability can be improved. Also,
For example, in FIG. 4, the display device image C exists near the left of the person image Pa, but when the region of the display device image C is to be printed together with the person image Pa, the region 19 of the distance image shown in FIG. By setting the threshold value stored in the threshold information memory 14 so that is selected together with the person image Pa, the person image Pa and the display device image C are set.
Can be formed. In addition, since the projection pattern is re-coded based on the imaging pattern input from the first camera 3A provided coaxially with the optical axis of the light projector 1, even if the reflectance of the surface of the imaging target is different, it is accurate. The distance can be measured.

FIG. 9 shows an image printing apparatus according to a second embodiment of the present invention. The second embodiment is different from the first embodiment in that a correction unit 9 that corrects the luminance value of the entire image based on the information of the human image extracted by the image extraction unit 7 is added. The portion for extracting only the person region from the luminance image is the same as in the first embodiment.

The correction unit 9 receives a human image from the luminance region extraction unit 12B and calculates a correction coefficient from the luminance distribution of the person region, and a correction coefficient calculated by the correction coefficient calculation unit 90. And an overall image correction unit 91 for correcting the luminance value of the overall image stored in the luminance image memory 6 based on the luminance.

FIG. 10 shows the luminance distribution of the extracted human image (FIG. 8). The horizontal axis represents the luminance value of each pixel, and the vertical axis represents the number of pixels of each luminance. The correction coefficient calculation unit 90 determines that the integrated value from the luminance value (0) is a% of the total number of pixels in the extraction area as a correction coefficient, and that the integrated value from the maximum luminance value (255) is a% Is calculated as Imax. The luminance value Imin is set to 0, and the luminance value Imax is set to 255.
By performing such a conversion, the contrast of the person region in the image is corrected.

The whole image correction section 91 converts the luminance value I of each pixel in the entire image into a corrected luminance value I 'using a correction formula such as the following equation (2). I ′ = [255 (I−Imin)} / {(Imax−Imin)} (2) That is, when the correction value I ′ becomes 0 or less, 0, 25
If the value is 5 or more, the correction value is output as 255.

FIG. 11 shows an example of the result of the correction processing. 2A shows the luminance distribution before the correction processing, FIG. 2B shows the luminance distribution after the correction processing, 60 denotes the luminance distribution in the entire area of the entire image, and 61 denotes the luminance distribution in the area of the person P. is there. The luminance distribution of the entire image (FIG. 4) before the correction processing is shown in FIG.
As shown in (b), the band 62 of the luminance value of the region of the person P is narrow, but as a result of performing the correction processing according to the above embodiment, as shown in FIG. 62
Can be widened, and an image of the person P with high contrast can be obtained.

FIG. 12 shows an image printing apparatus according to a third embodiment of the present invention. This third embodiment is similar to the first embodiment.
In the embodiment, the correction unit 9 that corrects the luminance value of the area of the person image based on the information of the extracted person image area
And a background memory 11a for storing desired background information in advance.
And a combining unit 11 that combines the human image corrected by the correcting unit 9 and the background image read from the background memory 11a to form print data. In addition,
The background information stored in the background memory 11a may be code information for specifying a single color, or may be an image.

The correction unit 9 calculates a correction coefficient as in the second embodiment, and corrects the luminance of the human image based on the correction coefficient calculated by the correction coefficient calculation unit 90. And an object image correction unit 92.

Next, the operation of the third embodiment will be described. The operation up to the operation of extracting the person image area from the luminance image is the same as in the first embodiment. After that, the correction coefficient calculation section 90 of the correction section 9 creates a luminance distribution of the region of the human image to obtain a correction coefficient. The object image correction unit 92 corrects the luminance value of the person area based on the correction coefficient obtained by the correction coefficient calculation unit 90. The combining unit 11 combines the corrected person image and the background information read from the background memory 11a to form print data. The printing unit 10 prints the image synthesized by the synthesizing unit 11 on paper.

According to the third embodiment, the background image combined with the portrait image can be changed freely.

FIG. 13 shows an image printing apparatus according to a fourth embodiment of the present invention. This fourth embodiment is similar to the first embodiment.
In the embodiment, the camera control unit 1 that controls the second camera 3B based on the information of the extracted person image area
00 is added.

The camera control unit 100 stores a control coefficient calculation unit 101 for calculating the position and the size of the human image in the whole image from the luminance region extraction unit 12B of the image control unit 8 as control coefficients, and the distance image memory 5 stores. Position detection unit 102 that calculates the position of the center of gravity of person P based on the position information
And the zoom of the second camera 3B based on the control coefficient calculated by the control coefficient calculation unit 101 and the center of gravity of the person P detected by the position detection unit 102 such that the person image is located substantially at the center of the entire image. And a signal control unit 103 that outputs a control signal for controlling the imaging direction.

Next, the operation of the fourth embodiment will be described. The operation up to the operation of extracting the person image area from the luminance image is the same as in the first embodiment. Thereafter, similarly to the second embodiment, the control coefficient calculation unit 101 forms a luminance distribution of the human image extracted by the luminance region extracting unit 12B, and changes camera parameters in accordance with the luminance distribution. Calculate the numerical value. For example, the position detection unit 102 calculates the center of gravity of the person P from the distance information, and calculates the amount of movement of the second camera 3B in the imaging direction such that the center of gravity of the person P is at the center of the image. The signal control unit 103 controls a direction parameter. The printing unit 10 prints the person image acquired from the second camera 3B.

According to the fourth embodiment, since a person image can be positioned at the center of the whole image, it is possible to image a person in a preferable image pickup state.

FIG. 14 shows an image printing apparatus according to a fifth embodiment of the present invention. This fifth embodiment is similar to the first embodiment.
In the third embodiment, a display unit 110 for performing display based on the extracted information on the person image area is added.

The display unit 110 calculates a center of gravity of the person P based on the distance information stored in the distance image memory 5, and a position detection unit 111 based on the position information detected by the position detection unit 111. A display control unit 112 for displaying information indicating a direction to be moved on the display 113.

Next, the operation of the fifth embodiment will be described. The operation up to the operation of extracting the person image area from the luminance image is the same as in the first embodiment. Then, the position detector 1
11 calculates the position of the center of gravity of the person image Pa in the entire image from the distance information, and selects an instruction such that the position of the center of gravity of the person image Pa is at the center of the entire image. Display control unit 112
Sends a display phrase to the display 113 and gives an instruction to the person P. The printing unit 10 prints a person image newly acquired from the second camera 3B.

According to the fifth embodiment, as in the fourth embodiment, it is possible to image a person in a suitable imaging state.

As a method of acquiring a distance image, for example, stereo image processing using the principle of triangulation may be used, or a phase distribution measurement method may be used. Further, it is desirable that each pixel of the luminance image and the distance image correspond to each other on a one-to-one basis, but it may be one-to-many.

[0041]

As described above, according to the image printing apparatus of the present invention, since the subject image is extracted from the luminance image based on the distance, the subject of the subject is changed even if the conditions such as the lighting conditions and the background change. The region can be accurately extracted, and thereby a clear image of the subject can be printed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an image communication device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of first and second cameras according to the embodiment of the present invention.

FIG. 3 is a view for explaining a distance measuring method by a projection pattern method according to the embodiment of the present invention;

FIG. 4 is a diagram obtained by imaging the person and the background according to the first embodiment;

FIG. 5 is a view showing a distance image according to the first embodiment;

FIG. 6 is a view showing an image obtained by separating a human part based on a distance image according to the first embodiment;

FIG. 7 is a view showing a distance image obtained by performing an interpolation process according to the first embodiment;

FIG. 8 is a diagram showing a print image obtained by extracting a part of a person according to the first embodiment;

FIG. 9 illustrates a configuration of an image printing apparatus according to a second embodiment of the present invention.

FIG. 10 is a view for explaining calculation of a correction coefficient by a correction coefficient calculation unit according to the second embodiment.

FIGS. 11A and 11B are diagrams illustrating an effect of the image printing apparatus according to the second embodiment, in which FIG. 11A is a luminance distribution before correction processing, and FIG. 11B is a luminance distribution after correction processing.

FIG. 12 is a diagram illustrating a configuration of an image printing apparatus according to a third embodiment of the present invention.

FIG. 13 is a diagram illustrating a configuration of an image printing apparatus according to a fourth embodiment of the present invention.

FIG. 14 is a diagram illustrating a configuration of an image printing apparatus according to a fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Projector 1a Projection pattern light 1b Reflected light 2 Half mirror 3A camera 3B camera 4 Processing unit 5 Distance image memory 6 Luminance image memory 7 Image extraction unit 8 Image control unit 9 Correction unit 10 Printing unit 11 Synthesis unit 11a Background memory 12A Distance image Acquisition unit 12B Luminance area extraction unit 13 Threshold processing unit 14 Threshold information memory 15 Interpolation processing unit 16 Area 17 Area 18 Area 19 Area 20 Background part 21 Dots 30 Prism 31 Invisible area cutoff filter 32 CCD camera for distance image 33 Invisible area transmission filter 34 CCD camera for luminance image 90 Correction coefficient calculation unit 91 Overall image correction unit 92 Object image correction unit 100 Camera control unit 101 Control coefficient calculation unit 102 Position detection unit 103 Signal control unit 110 Display unit 110 It is. 111 Position detection unit 112 Display control unit 113 Display P Person Pa Person image

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/232 H04N 5/232 Z 5C023 5/243 5/243 5C052 5/272 5/272 5C054 7/18 7/18 U 5C076 // G01B 11/00 G01B 11/00 B 11/24 G01C 3/06 A G01C 3/06 H04N 5/20 H04N 5/20 G01B 11/24 K F term (reference) 2F065 AA07 AA17 AA53 CC16 DD11 DD12 EE00 FF05 FF09 GG04 HH06 HH07 JJ03 JJ05 JJ26 LL00 LL06 LL26 LL46 PP01 QQ00 QQ24 QQ34 QQ43 SS13 2F112 AA09 CA08 CA12 DA15 FA08 FA09 FA32 FA45 2H104 AA19 BC48 5C021 PA53 APA PAA PA PA AB66 AC01 AC27 AC31 AC42 AC51 AC54 AC69 5C023 AA16 AA37 BA02 BA08 BA11 CA03 CA08 DA04 5C052 AA11 AA17 AB04 DD02 EE02 EE03 FA01 FA03 FA04 FB01 FB05 FC08 FD02 FD09 FD14 FE04 FE06 5C054 AA01 AA05 CC05 CF06 CG03 EA01 ED13 EJ04 FC14 FC15 FF02 GA05 GB01 GB04 GB14 GD03 HA14 5C076 AA01 AA11 AA19 AA40 BA02 BA06 CA02 CA11

Claims (11)

[Claims] An imaging unit that captures a background and a subject as an imaging target to obtain a luminance image; a measuring unit that measures a distance to the imaging target; and extracts a subject image from the luminance image based on the distance. An image printing apparatus comprising: an extracting unit that performs printing, a forming unit that forms print data based on the subject image, and a printing unit that performs printing based on the print data. 2. The apparatus according to claim 1, wherein said forming means includes a storage means for storing background information, and a synthesizing means for synthesizing said background information and said subject image to form said print data. Image printing device. 3. The image forming apparatus according to claim 1, wherein the forming unit corrects a luminance value of the entire luminance image based on a luminance distribution of the subject image, and forms the print data based on the corrected luminance image. The image printing apparatus according to claim 1, wherein the image printing apparatus has a configuration. 4. The image processing apparatus according to claim 1, wherein the forming unit includes a storage unit configured to store background information, a correction unit configured to correct a luminance value of the subject image based on a luminance distribution of the subject image, and a correction unit configured to correct the background information and the correction unit. The image printing apparatus according to claim 1, further comprising: a synthesizing unit configured to synthesize the subject image thus formed to form the print data. 5. An image printing apparatus according to claim 2, wherein said storage means stores said background information as code information specifying a color. 6. An image pickup device comprising: an image pickup device for picking up an image of an object to be picked up; and a changing unit for changing an image pickup direction of the image pickup device. 2. The image printing apparatus according to claim 1, further comprising control means for controlling said changing means so that a subject image is located in a predetermined area of said luminance image. 7. A determination means for determining whether or not the subject image is located in a predetermined area of the luminance image based on the distance and the subject image, and a determination result of the determination means And display means for displaying the print data based on the luminance image obtained by the imaging means when the determination means determines that the print data is located in the predetermined area. The image printing apparatus according to claim 1. 8. An image printing apparatus according to claim 1, wherein said measuring means measures a plurality of distances to a plurality of points on said imaging target to acquire a distance image. 9. A distance area extracting means for extracting a distance area within a predetermined distance range from the distance image, and a luminance image area corresponding to the distance area is extracted from the luminance image as the subject image. The image printing apparatus according to claim 7, further comprising a luminance image area extracting unit. 10. The image printing apparatus according to claim 8, wherein said distance area extracting means extracts a luminance image area corresponding to said blank area when a blank area exists in said distance area. 11. The image printing apparatus according to claim 1, wherein said imaging means captures said background and a plurality of said subjects as said imaging targets, and said extraction means extracts a plurality of said subject images.