JP2863753B1 - Texture acquisition method and texture acquisition system - Google Patents

Abstract

A texture acquisition method and a texture acquisition system capable of acquiring a high-quality texture of a three-dimensional object are provided. A texture acquisition system includes a movable measurement head and a fixed camera. The movable head 1 acquires the shape data and the texture (1) of the target object. The fixed camera 4 acquires a surface image of the target object according to the resolution. Computer 2
Generates a texture (2) according to resolution based on a plurality of surface images. Then, the generated texture (2) and the texture (1) are aligned by template matching. As a result, the correspondence between the texture (2) and the shape data is determined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a texture acquisition method and a texture acquisition system for generating a texture of a target object, and more particularly to a high quality texture required for generating three-dimensional computer graphics of the target object. To provide a texture acquisition method and a texture acquisition system capable of acquiring a texture.

[0002]

2. Description of the Related Art Generally, in order to digitize a three-dimensional object and generate computer graphics, it is necessary to obtain morphological information on shapes and textures.

FIG. 14 shows a conventional texture acquisition system 900 for acquiring information on the form of a three-dimensional object.
FIG. 2 is a diagram showing an example of the configuration of the display device, and a display device 3 that displays computer graphics of a target object.

A conventional texture acquisition system 900 shown in FIG. 14 includes a movable measuring head 1 and a computer 10.

The movable measuring head 1 irradiates a target object M with laser light and measures the reflected light. The movable measuring head 1 moves around the target object M under the control of the computer 10. The computer 10 processes the reflected light received by the movable measuring head 1 to generate shape data and texture (1) of the target object.

Here, a flow of processing by the conventional texture acquisition system 900 shown in FIG. 14 will be described with reference to FIG. FIG. 15 is a flowchart for explaining the flow of processing by the conventional texture acquisition system 900 shown in FIG.

[0007] As shown in FIG.
Obtains shape data and a surface image on the measurement surface of the target object M by irradiating a laser beam from the movable measurement head 1 (step S1).

Subsequently, the movable measuring head 1 is moved to the object M
Is rotated around (step S2). Then, the step S1 is executed for the entire circumference of the target object M (step S3).

A surface image measured over the entire circumference of the target object M is stored as a texture (1) in the storage medium 22 shown in FIG. The shape data measured on the entire circumference of the target object is stored in the storage medium 20 shown in FIG.

The display device 3 displays the target object M in response to the shape data and the texture (1) stored in the storage media 20 and 22. As a result, the target object M
3D computer graphics are reproduced.

[0011]

By the way, when the conventional texture acquisition system 900 described above is used, the movable measuring head 1 is moved (rotated). (For example, to provide stable illumination).

However, there is a problem that it is difficult to provide a constant and stable illumination over the entire circumference of the target object M.

Further, in the texture acquisition system 900 described above, the resolution cannot be changed, and the acquired texture always depends on the performance of a camera built in the movable measuring head 1. .

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a texture acquisition method and a texture acquisition system capable of acquiring a texture for generating high-quality computer graphics. It is in.

Still another object of the present invention is to provide a texture acquisition method and a texture acquisition system capable of easily changing the resolution of a texture regardless of the performance of a measuring device.

[0016]

According to a first aspect of the present invention, there is provided a texture acquisition system, comprising: a first imaging unit that moves with respect to a target object; It has a first acquisition unit that acquires data and a first texture, and a second imaging unit that captures a surface image of the target object, and is obtained by rotating the target object with respect to the second imaging unit. A second acquisition unit that acquires a second texture based on the plurality of surface images, and an association that associates the shape data with the second texture by associating the first texture with the second texture. Means.

A texture acquisition system according to a second aspect is the texture acquisition system according to the first aspect,
The second acquisition unit includes a first setting unit that sets a first resolution for the surface image, and an imaging unit that divides a surface of the target object based on the first resolution and captures an image using the second imaging unit. And a surface image generating means for obtaining a single surface image by combining the results of division and photographing based on the first resolution, and forming a plurality of surface images corresponding to the first resolution while rotating the target object. Control means for acquiring, second setting means for setting a second resolution for the second texture, and selecting one of the plurality of surface images based on the second resolution. And a texture generating means for generating a second texture by combining the extracted central areas according to the order of rotation.

A texture acquisition system according to a third aspect is the texture acquisition system according to the first aspect,
The associating means determines one point of the first texture corresponding to the shape data, and the template generating means for generating the template, and obtains the difference value while moving the template on the second texture, The second
And a control means for controlling all one points of the first texture to determine corresponding points on the second texture.

According to a fourth aspect of the present invention, there is provided a texture acquiring method, comprising: a movable first imaging device for measuring shape data of a target object and a first texture; A texture acquisition method in a texture acquisition system having the second imaging device, wherein the first imaging device is moved with respect to the target object to acquire shape data of the target object and the first texture. A second acquisition step of acquiring a second texture based on a plurality of surface images obtained by rotating the target object with respect to the second imaging device; A step of associating the shape data with the second texture by associating the second texture with the second texture.

A texture acquiring method according to a fifth aspect is the texture acquiring method according to the fourth aspect, wherein the second acquiring step comprises: a first setting step of setting a first resolution for the surface image; A photographing step of dividing the surface of the target object based on the first resolution and photographing with the second imaging means; and combining the photographed result of division based on the first resolution to obtain one surface image Surface image generating step, a control step for acquiring a plurality of surface images according to the first resolution while rotating the target object, and a second setting for setting a second resolution for the second texture. Setting step, selecting any one of the plurality of surface images based on the second resolution, and extracting a central region for each of the selected surface images; and extracting the central region By binding in the order of rotation, and a texture generation step of generating a second texture.

A texture acquisition method according to a sixth aspect is the texture acquisition method according to the fourth aspect, wherein the associating step determines one point of the first texture corresponding to the shape data and generates the template. A generation step, a difference value is obtained while moving the template on the second texture, and a difference step of obtaining a corresponding point on the second texture having a minimum difference value; On the other hand, the method includes a control step of repeating a template generation step and a difference step until a corresponding point on the second texture is determined.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION

[Embodiment 1] An example of the entire configuration of a texture acquisition system 100 according to Embodiment 1 of the present invention is shown in FIG.
This will be described with reference to FIG.

FIG. 1 is a diagram showing an example of the overall configuration of a texture acquisition system 100 according to the first embodiment of the present invention, and also shows a display device 3 for displaying computer graphics of a target object. .

As shown in FIG. 1, the texture acquisition system 100 includes a movable measuring head 1, a computer 2, a fixed camera 4, and a plurality of storage media 20, 22, 24,
26 and 28.

As described above, the movable measuring head 1
The target object M is irradiated with laser light and the reflected light is measured. The movable measuring head 1 moves (rotates) around the target object M under the control of the computer 2.

The computer 2 processes the reflected light received by the movable measuring head 1, generates shape data and texture (1) of the target object, and stores them in the storage media 20 and 22, respectively.

The fixed camera 4 captures a surface image of the target object M under the control of the computer 2. In photographing using the fixed camera 4, the target object M is
On top of. The photographed surface image is stored in the storage medium 24 as surface image data.

Here, the flow of computer graphics generation using the texture acquisition system 100 shown in FIG. 1 will be described with reference to FIGS. FIG.
Is a flow showing the flow of processing for generating computer graphics by the texture acquisition system 100 shown in FIG.

First, the shape data and texture (1) of the target object M are acquired using the movable measuring head 1 (step S10).

Next, using the fixed camera 4, the object M
Is obtained (step S11). The texture (2) is obtained based on the surface image data obtained in step S11 (step S12).

The texture (2) is associated with the shape data (step S13). Then, based on this association, computer graphics are generated and displayed on the display device 3.
(Step S14).

Hereinafter, each step shown in FIG. 2 will be described in detail. First, the flow of a surface image photographing process by the fixed camera 4 shown in FIG. 1 will be described with reference to FIG. FIG. 3 is a flowchart showing a flow of acquiring surface image data by the fixed camera 4 shown in FIG.

As shown in FIG. 3, first, the resolution X of the surface image to be obtained is set (step S20).
The user can freely change the resolution X for the surface image.

Next, the target object M is arranged on the turntable 5 (step S21). Under the control of the computer 2, a surface image of the target object M is obtained (step S2).
2). More specifically, the surface is divided and photographed according to the resolution X set in step S20. For example, when the resolution is set to high, the surface of the target object M is divided into a plurality of pieces and photographed. Then, the target images are obtained by joining the divided images.

Subsequently, the turntable 5 is rotated (step S23). Then, the above steps S22 and S
23 for the entire circumference of the target object (step S
24).

Thus, a surface image over the entire circumference of the target object M is obtained. FIG. 4 is a photograph showing an example of a surface image of the target object M captured by the fixed camera 4. The surface image shown in FIG. 4 is stored in the storage medium 24 as digital information (surface image data). It is assumed that N frames of surface image data are stored. Hereinafter, the surface image in the I-th frame is described as F (I) (where 1 ≦ I ≦ N).

When the fixed camera 4 is used, it is possible to take a picture under a fixed illumination (stable environment). It is also possible to change the resolution X to obtain a surface image according to the resolution.

Next, generation of the texture (2) will be described with reference to FIG. FIG. 5 is a schematic diagram for explaining generation of the texture (2), and the symbol A (I)
(However, 1 ≦ I ≦ N) is the I-th cut out in the following procedure.
The center area of the surface image F (I) in the second frame is shown.

As shown in FIG. 5, texture (2) is
It is generated by combining central regions A (I) cut out from each surface image F (I). Note that the number to be combined can be changed based on the resolution Y. This resolution Y is
Represents the number of surface images used to generate texture (2). The user can freely change the resolution Y for the texture (2). For example, when the resolution is set to a low resolution, a plurality of stored surface image data is used by thinning them out, and when the resolution is set to a high resolution, the number of thinnings is reduced.

Here, the flow of the process of generating the texture (2) shown in FIG. 5 will be described with reference to FIG. FIG.
6 is a flowchart illustrating a flow of a generation process of a texture (2) illustrated in FIG. 5. The computer 2 shown in FIG. 1 generates a texture (2) in the following procedure based on the surface images F (1) to F (N) acquired using the fixed camera 4.

First, the resolution Y of the texture (2) to be generated is set (step S30). Subsequently, the surface image F (I) for one frame is read from the storage medium 24 (step S31). Surface image F read out according to resolution Y
It is determined whether to use (I) (step S3)
2). If not, the process proceeds to step S36.

When used, the pixel width of the central region cut out from the display image F (I) is determined (step S3).
3). A central region A (I) is cut out from the read surface image F (I) according to the determined pixel width (step S).
34).

The extracted central area A (I) is combined (step S35). The image obtained as a result of the combination becomes the texture (2) as described above.

The steps S31 to S35 are performed for all frames, that is, N frames (step S36).

FIG. 7 is a photograph showing an example of the texture (2) generated in this manner. FIG. 8 is a photograph showing an example of the texture (1) acquired by the movable measurement head 1 used in the conventional computer graphics. By comparing FIG. 7 and FIG. 8, in the first embodiment of the present invention, the surface image F (1) obtained by the fixed camera 4
To F (N), a high-quality texture (2) corresponding to the resolution Y is generated. Further, as described above, the resolution Y
, It is possible to easily generate the texture (2) corresponding to various resolutions. The generated texture (2) is stored in the storage medium 26 shown in FIG.

Next, the correspondence between the generated texture (2) and the shape data will be described with reference to FIG. FIG. 9 is a photograph for explaining the association between the generated texture (2) and the shape data.

The texture (1) has a correspondence with the shape data. Therefore, using the computer 2 shown in FIG. 1, the texture (1) and the texture (2) are associated with each other to associate the texture (2) with the shape data. Specifically, as shown in FIG. 9, one point of the texture (1) is determined, and template matching is performed with the texture (2) using a square area around the point as a template. Thereby, the texture (1)
And the texture (2) are aligned.

Here, a flow of processing for associating the texture (2) with the shape data will be described with reference to FIG. FIG. 10 is a flowchart showing the flow of processing for associating texture (2) with shape data.

First, one point of the texture (1) is determined, and a square area around this point is used as a template (S
40).

The difference is calculated while moving the template from the upper left to the lower right on the texture (2). A point at which the difference value becomes minimum is obtained (step S41).

Steps S40 to S41 are repeated for all points corresponding to the shape data until points on the texture (2) are determined (S42).

As a result, a high quality texture (2) can be associated with the shape data. Information (correspondence information) for associating these is the storage medium 2 shown in FIG.
8 is stored.

With this configuration, the shape data (stored in the storage medium 20), the texture (2) (stored in the storage medium 26) and the corresponding information (stored in the storage medium 28)
, It is possible to generate high-quality three-dimensional computer graphics for the three-dimensional target object M.

FIGS. 11 to 13 show Embodiment 1 of the present invention.
4 is a photograph for explaining the effect of the present invention. FIG.
(A) is a photograph showing an example of computer graphics reproduction by a conventional method (using texture (1)), and FIG. 11 (B) is a computer graphics reproduction according to Embodiment 1 of the present invention. 3 is a photograph showing an example of the above. FIG. 12 is an enlarged photograph of a part of the computer graphics according to the conventional method shown in FIG. 11A, and FIG. 13 is a computer graphic according to the first embodiment of the present invention shown in FIG. This is an enlarged photograph of a part of the graphics.

As shown in FIGS. 11 to 13, according to the first embodiment of the present invention, it can be seen that the transition of the surface pattern in computer graphics is smoother than in the prior art. That is, high-quality computer graphics can be generated.

[0056]

As described above, according to the texture acquisition method and the texture acquisition system according to the present invention, it is possible to generate a high-quality texture of a target object based on a surface image obtained under a stable shooting environment. it can.

Further, this makes it possible to generate high-quality three-dimensional computer graphics relating to a three-dimensional target object.

Further, according to the present invention, by changing the resolution of the surface image or the resolution of the texture (2), the resolution of the texture image can be changed without further measuring the shape data. It can be changed freely.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of an overall configuration of a texture acquisition system 100 according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing the flow of processing for performing computer graphics using the texture acquisition system 100 shown in FIG.

FIG. 3 is a flowchart showing a flow of acquiring surface image data by the fixed camera 4 shown in FIG. 1;

4 is a photograph of a halftone image showing an example of a surface image of a target object M captured by a fixed camera 4 displayed on a display device 3. FIG.

FIG. 5 is a schematic diagram for explaining generation of a texture (2).

FIG. 6 is a flowchart showing a flow of processing for generating a texture (2) shown in FIG. 5;

7 is a photograph of a halftone image showing an example of a generated texture (2) displayed on the display device 3. FIG.

FIG. 8 is a photograph of a halftone image showing an example of a texture (1) acquired by the movable measuring head 1 displayed on the display device 3.

9 is a photograph of a halftone image showing a process for associating the texture (2) displayed on the display device 3 with the shape data. FIG.

FIG. 10 is a flowchart showing the flow of processing for associating texture (2) with shape data.

FIG. 11 is a photograph of a halftone image of computer graphics displayed on the display device 3 for explaining the effect of the first embodiment of the present invention.

FIG. 12 is a photograph of a halftone image in which a part of computer graphics is enlarged on the display device 3 according to the conventional method shown in FIG.

FIG. 13 is a photograph of a halftone image in which a part of the computer graphics according to the first embodiment of the present invention shown in FIG. 11B is enlarged and displayed on the display device 3;

FIG. 14 is a diagram showing an example of the configuration of a conventional texture acquisition system 900 for acquiring information on the form of a three-dimensional object.

FIG. 15 is a flowchart for explaining the flow of processing by the conventional texture acquisition system 900 shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Movable measuring head 2 Computer 3 Display device 4 Fixed camera 5 Rotary table 20, 22, 24, 26, 28 Storage medium 100 Texture acquisition system

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-8-14858 (JP, A) JP-A-5-303629 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G06T 7/00-7/60 G06T 15/00-17/50

Claims (6)

(57) [Claims] A first imaging unit that moves with respect to a target object; and a first imaging unit that moves the first imaging unit to acquire shape data and a first texture of the target object. Acquiring means, having a second imaging means for photographing a surface image of the target object, based on a plurality of the surface images obtained by rotating the target object with respect to the second imaging means,
A second acquisition unit that acquires a second texture; and an association unit that associates the shape data with the second texture by associating the first texture with the second texture. Equipped with a texture acquisition system. 2. The method according to claim 1, wherein the second acquisition unit is configured to: set a first resolution for the surface image, and divide the surface of the target object based on the first resolution. Photographing means for photographing with a second imaging means; surface image generating means for combining the divided and photographed results based on the first resolution to obtain one surface image; Control means for acquiring a plurality of the surface images according to the first resolution while rotating, second setting means for setting a second resolution for the second texture, and the second A cutting unit that selects any one of the plurality of surface images based on a resolution and cuts out a central region for each of the selected surface images; and combines the cut-out central regions in the order of the rotation. And by, the first including second and texture generating means for generating a texture, claim 1 texture acquisition system according. 3. The associating unit: a template generating unit that determines a point of the first texture corresponding to the shape data and generates a template; and moves the template over the second texture. Difference means for taking a difference value while obtaining a corresponding point on the second texture at which the difference value is minimum; and for all the one points of the first texture, the difference on the second texture The texture acquisition system according to claim 1, further comprising control means for controlling the corresponding point to be determined. 4. A movable first imaging device for measuring shape data and a first texture of a target object, and a fixed second imaging device for capturing a surface image of the target object. A texture acquisition method in a texture acquisition system, comprising: moving the first imaging device with respect to the target object to obtain the shape data and the first texture of the target object. A second step based on the plurality of surface images obtained by rotating the target object with respect to the second imaging device.
A second acquisition step of acquiring the texture of the first and second textures, and an associating step of associating the shape data with the second texture by associating the first texture with the second texture. Texture acquisition method. 5. The method according to claim 5, wherein the second obtaining step includes: a first setting step of setting a first resolution for the surface image; and dividing the surface of the target object based on the first resolution. A photographing step of photographing with a second photographing means; a surface image generating step of combining the divided photographed results based on the first resolution to obtain one surface image; and rotating the target object A control step for acquiring a plurality of the surface images corresponding to the first resolution, a second setting step for setting a second resolution for the second texture, and the second A step of selecting any one of the plurality of surface images based on a resolution and cutting out a central region for each of the selected surface images; and Of by binding in the order, the first including second and texture generation step of generating a texture, claim 4 texture acquisition method according. 6. The associating step includes: determining a point of the first texture corresponding to the shape data, and generating a template; and moving the template over the second texture. A difference step of obtaining a corresponding point on the second texture in which the difference value is minimized, and for all the one points of the first texture, 5. The texture acquisition method according to claim 4, further comprising a control step of repeating the template generation step and the difference step until a corresponding point is determined.