JP2000050115A - Photographing method and photographing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a device compact, to reduce energy consumption and reduce a cost of the entire device by emitting light with the same color and uniform light quantity in the case of photographing by supplying small amount of energy to the background. SOLUTION: The light is emitted with the same color and the uniform light quantity in the case of photographing by supplying the small amount of energy to the background 12. An image of an object Ob is picked up with the background 12 by driving en electronic camera 11b at a state that the color of clothes is differentiated from the color of the background 12 by an image processing substrate 11a in the device. Next, a chroma key image is composited by the image processing substrate 11a, in this case, difference between the total image signal value obtained from the electronic camera 11b and an image signal value based on the color of the background 12 is calculated. In this case, the difference becomes zero regarding a part corresponding to the background 12. Therefore, segmentation of the object Ob is enabled by regarding an area in which the difference becomes zero when the chroma key image is composited as the background.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called chroma key image synthesizing technique for separating and processing an image signal component relating to a background and an image signal component relating to the subject, and particularly relates to a seal, a postcard, a calendar and an ID card. And a technology for forming an image of a person on an arbitrarily selected background in a license, a ticket, a commuter pass, or the like.

[0002]

2. Description of the Related Art After setting a background to, for example, a single color blue, and photographing a subject together with the background and converting it into an image signal, an image signal component relating to the background and an image signal component relating to the subject are separated. By doing so, a so-called chroma key image synthesizing technique is known, in which only a subject is cut out from an image and fitted into another background.

According to such a chroma key image synthesizing technique,
For example, the image of the southern island can be placed in the background of a person photographed in the studio in a natural state, so that an image as if the person was photographed on the southern island can be formed. ing.

In the chroma key image synthesizing method, the first problem is how to naturally extract only the subject from the background. In the chroma key image synthesizing technique, the wavelength component of the background light is obtained in advance, and any object having a wavelength component of light different from this is regarded as a subject. Therefore, if the subject is wearing clothes of the same color as the background, the clothes are also regarded as the background, and only the other subjects are cut out to form an unnatural image. .

On the other hand, if a shadow of an object is reflected on a part of the background, for example, the wavelength component of light in the shadow part is different from the wavelength component of the other part of the background. And may be considered. Therefore, the background needs to be strictly uniform in color, and the subject (especially clothes of a person, etc.) needs to be different in color from the background.

In the prior art, on the other hand, the background is, for example, a single color blue, which is irradiated with illumination light from a fluorescent lamp or the like, and a person is arranged before the photographing to perform photographing. However, it is difficult to make the reflected light from the background uniform due to the problem of the arrangement of the lighting lamps, and a shadow of a person may be reflected on the background. In such a case, if the chroma key image synthesis is performed, a part of the background may be erroneously recognized as the subject.

Therefore, the background is replaced with a translucent plate member, and a plurality of fluorescent lamps are used to irradiate the background with a plurality of fluorescent lamps so that the front surface of the background emits the same color, thereby facilitating the recognition of the background. Has been already developed.

[0008]

However, such a photographing apparatus has a background configuration including an irradiating apparatus, consumes a relatively large amount of energy for causing the background to emit light, increases the size of the entire apparatus, and This raises a problem that the cost increases.

Further, the background color should be permanently the same, but there is a problem in how to deal with the change in the emission color due to the aging of the fluorescent lamp. In addition, since the fluorescent lamp itself is cylindrical but the background is plate-shaped, there is a problem that even if a plurality of fluorescent lamps are used, it is difficult to make the luminance of the background exactly the same over the entire surface. . Another problem is how to distinguish between the background and the subject when the color of the background matches the color of the subject.

[0010] In addition, there is a problem of how to delete a shadow that may cause the background to be erroneously recognized as a part of the subject. In addition, depending on the position of the illumination lamp, a shadow of the subject may be formed on the subject, but this may cause a poor image of the subject. Therefore, there is a problem of how to remove the shadow.

The present invention has been made in view of the problems of the prior art, and provides a photographing method and a photographing apparatus capable of reducing the size of the photographing apparatus, reducing energy consumption, and reducing the cost of the entire apparatus. The purpose is to:

[0012]

In order to achieve the above object, a photographing method according to the present invention is a photographing method for photographing an image including a subject and a background, and the image is converted into an image signal based on the photographing. An imaging method wherein the image signal component on the background is further converted and the image signal component on the subject can be separated, and by supplying a small amount of energy to the background, And emits light with a uniform light amount.

[0013] A photographing method of the present invention includes the steps of: irradiating a subject with photographing light and reflecting or emitting light having a single special wavelength component from a background; Comparing the wavelength component of light from the background, and, if the wavelength components match, changing at least one of the wavelength component of the photographing light and the wavelength component of the light from the background; Photographing an image including the subject and the background by using an image.

A photographing method according to the present invention is a photographing method for photographing an image including a subject and a background, wherein the image is converted into an image signal based on the photographing, and further, an image signal component relating to the background, In a photographing method wherein an image signal component relating to the subject can be separated, a step of detecting a light characteristic value from the background at a predetermined timing; and detecting the light characteristic value based on the detected light characteristic value. And separating the image signal component of the subject from the image signal component of the subject.

The photographing apparatus of the present invention has a background, a plurality of light sources for illuminating the subject, and a photographing apparatus for photographing the subject and the background at the same time.
The shape of the background and the positions of the plurality of light sources are adjusted such that the shadow of the subject due to the illumination light from the plurality of light sources is formed at a position invisible when the photographing apparatus is viewed from the viewpoint. It is characterized by the following.

The photographing device of the present invention has a plurality of light sources for illuminating the subject and a photographing device for photographing the subject.
The plurality of light sources are characterized in that a shadow of the subject itself generated on the subject by illumination light from one light source is erased by illumination light from the other light source.

[0017]

According to the photographing method of the present invention, by supplying a small amount of energy to the background, light is emitted in the same color and with a uniform light amount at the time of photographing, so that the color of the photographed background becomes uniform. When synthesizing the chroma key image, the image signal component of the subject and the image signal component of the background can be reliably separated, whereby the quality of the synthesized image can be improved and energy can be saved.

According to the photographing method of the present invention, a step of irradiating a subject with photographing light and reflecting or emitting light having a single special wavelength component from a background is performed. Comparing the wavelength component of the light from the background, and if the wavelength components match, changing at least one of the wavelength component of the photographing light and the wavelength component of the light from the background, Photographing an image including the subject and the background using a photographing device, for example, if the clothes worn by the person who is the subject are the same color as the background, By changing the color or the characteristics of the illumination light of the subject, it is possible to reliably separate the signal component of the subject from the signal component of the background during the synthesis of the chroma key image. It is possible to improve the quality of the more composite images. When shooting using the shooting method of the present invention,
Even if the background and the clothes of the person have the same color, an image can be extracted by determining a threshold based on light information obtained from each other. According to this invention, it is possible to reliably detect a pattern that cannot be detected by the related art. The above-mentioned special wavelength component refers to, for example, a wavelength component of light emitted from a phosphor.

According to the photographing method of the present invention, a step of detecting a light characteristic value from the background at a predetermined timing; an image signal component relating to the background based on the detected light characteristic value; A step of separating the image signal component of the subject from the image signal component. Therefore, even when the light characteristic of the background deteriorates with time, the light characteristic value is detected at a predetermined timing (for example, at the time of starting the photographing device). hand,
By deriving the latest image signal component for the background based on this, it is possible to reliably separate the signal component of the subject from the signal component of the background during the synthesis of the chroma key image, thereby improving the quality of the synthesized image. it can.

According to the photographing apparatus of the present invention, the shadow of the subject projected on the background by the illumination light from the plurality of light sources is formed at a position invisible when the photographing apparatus is viewed from the viewpoint. As described above, since the shape of the background and the positions of the plurality of light sources are adjusted, the image quality of the photographed subject can be improved.

According to the photographing apparatus of the present invention, in the plurality of light sources, the shadow of the subject itself, which is generated on the subject due to the illumination light from one light source, is erased by the illumination light from the other light source. Therefore, the image quality of the photographed subject can be improved.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments. FIG. 1 is a perspective view of a photographing apparatus according to an embodiment of the present invention. In FIG. 1, a photographing device 10
Is a box-shaped photographing unit 11 and a background 1 opposed thereto.
And 2. The background 12 is in the form of a curtain suspended from a horizontal bar 13a extending horizontally from the upper end of the pillar 13, and has a high flexibility and is hardly damaged. The background 12 is not suspended from a pillar as in the present embodiment, but may be suspended from a ceiling or a wall if it is indoors, or may be attached to another structure. It may be. A light source 14 capable of irradiating highly directional light is disposed above the imaging unit 11, while a solar cell 15 is disposed above the background 12 (upper end of the column 13).

The background 11 has a so-called electroluminescence structure in which a large number of LEDs (not shown) supplied with power from a solar cell are arranged on the entire surface of the photographing unit 11, and the LED emits blue-green light. There are two types of blue-violet, which are arranged alternately. The subject O
A shielding member 17 (indicated by a dotted line) is arranged so as to shield the upper part and the side part between the photographing unit 11 and the background 12 so that the outside light does not accidentally hit b.

FIG. 2 is a schematic view of the photographing apparatus 10 as viewed from above. In the photographing unit 11 (FIG. 1), an image processing board (unit) 11a, an electronic camera 11b connected to the image processing board 11a, an illumination lamp 11c,
11d and a sensor 11 for detecting a light emission characteristic value of an LED
e and 11f, and a printer 11g. The light emitted from the background 12 is also transmitted to the image processing board 1 via the cable Cb.
1a is controlled. As shown in FIG.
The cable Cb is connected to the background 1 via the pillar 13 from the photographing unit 11.
2 has been reached. The sensors 11e, 11f
Although only two are shown, many sensors are arranged so that the entire surface of the background 12 can be detected.

The operation of this embodiment will be described with reference to FIGS. First, in a state where the object Ob is positioned in front of the background, the light source 14 is turned on by driving from the image processing substrate 11a, and the irradiation light of the solar cell 15 is emitted. Upon receiving such irradiation light, the solar cell 15 supplies a predetermined power and first emits a blue-green LED.

In this state, the sensors 11e and 11f
The light emission characteristics of the background 12 are detected. Such detection is performed at a predetermined timing, for example, each time shooting is started. More specifically, the chromaticity and lightness of the LED are converted into R, G, and B values, which are stored in the image processing board 11a. They are stored in the means. The R, G, and B values are used when synthesizing a chroma key image described later.

Next, the image processing board 11a is
Lights c and 11d to illuminate the subject Ob. Illumination light 1
Since 1c and 11d illuminate the subject Ob from the left and right,
The shadow S of the subject Ob occurring on the background 12 is formed at a position invisible from the electronic camera 11b. Further, since the surface of the background 12 is appropriately curved, the reflected light from the background 12 does not further form a shadow on the subject Ob.

By the way, since the skin color and the hair color of the object Ob are clearly different from the background color, they can be clearly separated when the chroma key image is synthesized. However, when the clothing C (FIG. 1) of the subject Ob has the same bluish green color as the background 12, there is a possibility that the subject Ob and the background 12 cannot be appropriately separated during the synthesis of the chroma key image. Therefore, the sensor 11
e, 11f detect the color of the clothes C and determine that the color is the same as the color of the background 12;
Turns off the blue-green LED of the background 12 and turns on the blue-violet LED instead.

Since the emission color of the background 12 is constant irrespective of the characteristics of the illumination light, the clothing C of the subject Ob is
In the case of having the same color as the above, it is conceivable to change the reflection color of the clothes C by changing the light emission characteristics of the illuminations 11c and 11d. If the light emission characteristics of the illumination lamps 11c and 11d are known, the original color can be reproduced at the time of image processing in a later process. Alternatively, one of the backgrounds having different emission colors may be knocked up and the other hung down, and when it is determined that the clothing of the subject has the same color as the background, one of the backgrounds may be hung down and the other is knocked up.

In this way, the image processing board 11a drives the electronic camera 11b and captures the image of the subject Ob together with the background 12, with the clothing color and the background color being different. Next, the image processing board 11a performs chroma key image synthesis, and at this time, takes the difference between the total image signal value obtained from the electronic camera 11a and the image signal value based on the color of the background 12. At this time, the difference is zero for the portion corresponding to the background. Therefore, when the chroma key image is synthesized, the region where the difference becomes zero is regarded as the background, and the object O
It becomes possible to cut out only b. Image processing board 11
In a, a cut-out subject Ob is inserted into an arbitrary background to create a composite image, and the composite image is printed via a printer 11g.

As a modified example of the background in which light emission is performed uniformly and uniformly with low power consumption, it is conceivable to use, for example, a light storage member. The light storage member is a member that emits light for a certain period of time when irradiated with light. By forming the phosphorescent member in a curtain shape,
This can be used as a background of this embodiment. At the time of photographing, the light storage is achieved by causing the light storage member to emit black light (e.g., light of a wavelength that cannot be detected by the human eye, such as infrared light or ultraviolet light). The illuminance of the light storage member is measured by a sensor, and when the illuminance decreases, a black light may be emitted. In addition, using a timer,
Black light may be emitted periodically to store light regardless of shooting. In addition, as another modified example of the background in which light emission is performed simply and uniformly over the entire surface with low power consumption, for example, a light guide plate or a member coated with a fluorescent paint may be used. The light guide plate refers to, for example, a member that uniformly emits light from the front surface by adjusting the coarse density of light irradiated from the side surface with a small reflector embedded in a plastic material.

One problem when using a light storage member, a light guide plate, or a member coated with a fluorescent paint is that the characteristic value of the emitted light or the reflected light changes with time.

FIG. 3 is a graph showing the change over time of the light emission characteristics of a certain light storage member. As described above, the light-storing member may slightly emit light frequency f or illuminance D over time.
Changes. Therefore, when the light emission color of the light storage member is treated as invariable, when the difference between the total image signal value obtained from the electronic camera 11a and the image signal value based on the color of the background 12 is calculated, the background area becomes zero. Instead, it may be recognized as a subject. On the other hand, according to the present embodiment, even when the light storage member has deteriorated with time, the light emission characteristics thereof are detected at a predetermined timing, for example, before the start of photographing. When the difference between the total image signal value and the image signal value based on the color of the background 12 is calculated, the background area is always zero, which makes it possible to appropriately perform the chroma key image synthesis processing. When the dimming reaches the limit,
The light storage member needs to be replaced. It should be noted that a light guide plate or a member coated with a fluorescent paint can be used in the same manner.

Further, when the object Ob is cut out from the background, a black shadow or blue noise may appear on the outline of the cut out image. This is a peculiar phenomenon that occurs when an electronic camera (CCD element or image pickup tube) is used, and has a characteristic that it is likely to occur on a boundary line having a large contrast. In order to prevent this, illumination can be made as close as possible to indirect light, or noise can be removed by image processing (anti-aliasing). What is anti-aliasing?
Image processing in which black shadows and blue noise are made difficult to see by intentionally blurring the border.

As described above, according to the present embodiment, the background 1
By making 2 a curtain shape, the configuration of the photographing apparatus can be made compact and its cost can be reduced. In addition, since the background has a curtain shape, the installation space for the photographing device can be reduced, and the background itself is not easily damaged. Further, since the shape of the background and the position of the illuminating light are appropriately set, the shadow of the subject can be generated at a position where the electronic camera does not take a picture, thereby improving the image quality.

On the other hand, since the background 12 has an electroluminescence structure, uniform light emission can be achieved over the entire surface, and an appropriate chroma key image synthesizing process can be performed. Further, by obtaining the background power from the solar cell, it is not necessary to lay the wiring from the photographing device, and power saving can be achieved.

FIG. 4 is a diagram showing a modification of the photographing apparatus according to the present embodiment. In FIG.
c and 11d are arranged vertically. With only the main illumination lamp 11c arranged above, the shadow S of the chin is generated on the subject Ob, and the image quality may be degraded. Therefore, the illumination lamp 11d is disposed below as a sub, and the shadow S is erased by the illumination light. It should be noted that, by using a type having high directivity as the illuminating lamp 11d, it is possible to illuminate only the region where the shadow S of the chin occurs, and thereby the shadow S is formed without adversely affecting the illumination by the main illuminating lamp 11c. It can be erased.

FIG. 5 is a diagram showing another modification of the present embodiment. This embodiment is different from the embodiment of FIG. 2 in that a power supply cable 16 is arranged along a pillar 13 in parallel with a control cable Cb from an image processing board 11a to a background 12. That is the point. According to this modified example, since power is supplied by wire, there is an advantage that power can be supplied stably.

Although the present invention has been described with reference to the embodiment, the present invention should not be construed as being limited to the above-described embodiment, and it is needless to say that the present invention can be appropriately changed / improved. is there. For example, as a mode in which only the subject is cut out from the background, the subject may be continuously photographed in a short time in a state where the lighting lamp is turned off and a state where the lighting lamp is turned on. Since only the background is photographed in a state where the illumination lamp is turned off, it is possible to identify a subject in a state where the illumination lamp is turned on using such a condition. Such identification is inappropriate if the subject moves during continuous shooting, but if the continuous shooting is short, the amount of movement of the subject is considered to be small or even small, Identification becomes valid.

For the identification of the subject in the chroma key image synthesizing process, a value depending on the wavelength of light, a value depending on the light amount, or a value depending on the light energy may be used. good.

[0041]

According to the photographing method of the present invention, a small amount of energy is supplied to the background to emit light of the same color and a uniform light amount at the time of photographing, so that the color of the photographed background becomes uniform. Accordingly, when synthesizing the chroma key image, the image signal component of the subject and the image signal component of the background can be reliably separated, whereby the quality of the synthesized image can be improved and energy can be saved.

According to the photographing method of the present invention, the object is irradiated with photographing light, and light having a single special wavelength component is reflected or emitted from the background. Comparing the wavelength component of the light from the background, and if the wavelength components match, changing at least one of the wavelength component of the photographing light and the wavelength component of the light from the background, Photographing an image including the subject and the background using a photographing device, for example, if the clothes worn by the person who is the subject are the same color as the background, By changing the color or the characteristics of the illumination light of the subject, it is possible to reliably separate the signal component of the subject from the signal component of the background during the synthesis of the chroma key image. It is possible to improve the quality of the more composite images. When shooting using the shooting method of the present invention,
Even if the background and the clothes of the person have the same color, an image can be extracted by determining a threshold based on light information obtained from each other. According to this invention, it is possible to reliably detect a pattern that cannot be detected by the related art.

According to the photographing method of the present invention, at a predetermined timing, a step of detecting a light characteristic value from the background, based on the detected light characteristic value, an image signal component relating to the background and the object And a step of separating the image signal component from the image signal component. Therefore, even if the light characteristic of the background deteriorates with time, the light characteristic value is detected at a predetermined timing (for example, when the photographing apparatus is started). By deriving the latest image signal component relating to the background based on this, it is possible to reliably separate the signal component of the subject from the signal component of the background during the synthesis of the chroma key image, thereby improving the quality of the synthesized image. Can be.

According to the photographing apparatus of the present invention, the shadow of the subject projected on the background by the illumination light from the plurality of light sources is formed at a position that cannot be seen from the viewpoint of the photographing apparatus. Since the shape of the background and the positions of the plurality of light sources are adjusted, the image quality of the photographed subject can be improved.

According to the photographing apparatus of the present invention, the plurality of light sources are such that the shadow of the subject itself, which is generated on the subject by the illumination light from one light source, is erased by the illumination light from the other light source. Therefore, the image quality of the photographed subject can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a photographing apparatus according to an embodiment of the present invention, in which a subject is arranged between a photographing unit and a background.

FIG. 2 is a schematic view of the photographing device 10 as viewed from above.

FIG. 3 is a graph showing a change over time in light emission characteristics of a certain LED.

FIG. 4 is a diagram showing a modification of the photographing apparatus according to the embodiment.

FIG. 5 is a diagram showing another modification of the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Imaging device 11 Imaging part 11a Image processing board (unit) 11b Electronic camera 11c, 11d Illumination light 11e, 11f Sensor 12 Background 13 Column 13a Horizontal bar 14 Light source 15 Solar cell 16 Power supply cable 17 Shielding member Cb Control cable Ob Subject S Shadow

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 9/75 G06F 15/66 450

Claims (11)

[Claims] 1. An image capturing method for capturing an image including a subject and a background, wherein the image is converted into an image signal based on the capturing, an image signal component related to the background, and an image signal related to the subject. A photographing method capable of separating components from each other, wherein a small amount of energy is supplied to the background to emit light of the same color and a uniform light amount during photographing. 2. The method according to claim 1, wherein the background is formed using an electroluminescence structure. 3. The photographing method according to claim 1, wherein the background is formed using a luminous luminous body. 4. The method according to claim 1, wherein the background is formed using a light guide. 5. The method according to claim 1, wherein the background is formed using a member coated with a fluorescent paint. 6. The method according to claim 1, wherein the background has a foldable curtain shape. 7. A step of irradiating a subject with photographing light and reflecting or emitting light having a single special wavelength component from a background; and a wavelength component of the reflected light of the subject and a light of the light from the background. Comparing the wavelength component with the wavelength component; and, if the wavelength components match, changing at least one of the wavelength component of the photographing light and the wavelength component of the light from the background. Capturing an image including an image and the background. 8. A photographing method for photographing an image including a subject and a background, wherein the image is converted into an image signal based on the photographing, and further, an image signal component related to the background,
A photographing method capable of separating an image signal component relating to the subject from light; detecting a light characteristic value from the background at a predetermined timing; and detecting the background based on the detected light characteristic value. And a step of separating the image signal component related to the subject from the image signal component related to the subject. 9. A light source, comprising: a background; a plurality of light sources for illuminating a subject; and a photographing device for simultaneously photographing the subject and the background; and illuminating light from the plurality of light sources projected on the background. The shape of the background and the positions of the plurality of light sources are adjusted such that a shadow of the subject due to the above is formed at a position where the shadow becomes invisible when the viewpoint of the photographing device is viewed. 10. The background of the background such that a shadow generated by irradiating the subject with illumination light reflected from the background is formed at a position where the shadow becomes invisible when viewing the imaging device as a viewpoint. The photographing apparatus according to claim 9, wherein a shape and positions of the plurality of light sources are adjusted. 11. A light source for illuminating a subject, and a photographing device for photographing the subject, wherein the plurality of light sources have a shadow of the subject itself generated on the subject by illumination light from one of the light sources. An imaging device, wherein the image is erased by illumination light from the other light source.