JP2004054572A - Method and device for editing three-dimensional model - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the data quantity of a three-dimensional model to make it compact, and to hold the characteristic part of the three-dimensional model. <P>SOLUTION: This three-dimensional model editing device in which texture images are mapped is provided with: a means for designating a specific area TR on the texture image existing corresponding to an area on a three-dimensional model ML; a means for converting the resolutions of texture images concerning the specific area TR and an outside-specific area TS other than the specific area existing corresponding to the area on the three-dimensional model in order to make those resolutions different from each other; an image integrating means for integrating all texture images FGS whose resolutions are converted as one or more new texture images FTS; and a means for updating a corresponding table TB2 of the integrated texture image FTS with the three-dimensional model. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for editing a three-dimensional model.
[0002]
[Prior art]
In recent years, non-contact three-dimensional shape input devices are often used in the fields of CG and industrial design. The three-dimensional shape input device irradiates a target object (object) with a laser or pattern light, captures light reflected on the surface of the target object with a sensor, thereby densely sampling the three-dimensional shape of the target object, and performs three-dimensional sampling. Shape data can be generated. In addition, a real three-dimensional model of the object can be obtained by taking an image of the entire circumference of the object together with the measurement of the three-dimensional shape and pasting the image as texture to the three-dimensional shape data.
[0003]
Now, the three-dimensional model obtained in this way usually has a large data amount. Therefore, when the three-dimensional model is handled inside a workstation or a personal computer, there is not much problem. However, when the three-dimensional model is placed on a network such as a web, it takes a long time to transfer the data. difficult. Moreover, in a PDA or a mobile phone used as a terminal for a network, since a memory capacity and a processing capacity are small, it is not realistic to directly handle a three-dimensional model.
[0004]
Conventionally, the three-dimensional model is reduced at an appropriate ratio according to the purpose, thereby reducing the data amount and facilitating the processing.
[0005]
[Problems to be solved by the invention]
As described above, conventionally, since the three-dimensional model is reduced at a fixed ratio, the image pasted on the three-dimensional model also becomes smaller accordingly. Therefore, for example, when the target object is a person or the head of a person, an image such as an eye or eyebrows is crushed, and a facial feature such as a facial expression cannot be understood.
[0006]
The present invention has been made in view of the above-described problems, and has an apparatus and an apparatus for editing a three-dimensional model capable of reducing the amount of data of the three-dimensional model to be compact and retaining a characteristic part of the three-dimensional model. The purpose is to provide.
[0007]
[Means for Solving the Problems]
In the method according to the present invention, there is provided a method for editing a three-dimensional model on which a texture image is mapped, wherein a specific area on the three-dimensional model is specified, and a specific area on the three-dimensional model and other areas are specified. And re-mapping to the three-dimensional model so that the resolutions of the texture images are different from each other.
[0008]
In the apparatus according to the present invention, the means for designating a specific area on the three-dimensional model, and the three-dimensional model may be configured such that the resolution of the texture image differs between the specific area and the other area on the three-dimensional model. Means for re-mapping to the model.
[0009]
Also, in the apparatus according to the present invention, means for designating a specific area on the texture image that exists corresponding to the area on the three-dimensional model, and the specific area and the area other than the specific area for the texture image Means for converting the resolution so that the resolutions are different from each other with respect to the non-specific area existing corresponding to the area on the three-dimensional model; and for all the texture images whose resolutions have been converted, It has image integration means for integrating as one or a plurality of new texture images, and means for updating the correspondence between the integrated texture image and the three-dimensional model.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a block diagram of a three-dimensional model editing apparatus 1 according to an embodiment of the present invention.
[0011]
In FIG. 1, an editing apparatus 1 includes an apparatus main body 10, a magnetic disk device 11, a medium drive device 12, a display device 13, a keyboard 14, a mouse 15, and the like.
[0012]
The apparatus main body 10 includes a CPU, a RAM, a ROM, a video RAM, input / output ports, various controllers, various interfaces, and the like. Various functions described below are realized by the CPU executing programs stored in the RAM, the ROM, and the like.
[0013]
The magnetic disk device 11 includes an OS (Operating System), a modeling program PR for generating a three-dimensional model (three-dimensional shape model) ML or performing texture mapping, other programs, and input or generated three-dimensional data. (Three-dimensional shape data) DT, an image (two-dimensional image data) FT, a generated three-dimensional model ML, and other data are stored. The three-dimensional model ML includes a normal three-dimensional model and a reduced three-dimensional model. Particularly, when referring to a reduced three-dimensional model, the “three-dimensional model MLS” or “reduced three-dimensional model MLS” is used. ". The same applies to the image FT. In particular, when referring to a reduced image for the three-dimensional model MLS, it may be described as “image FTS” or “reduced image FTS”. These programs and data are loaded into the RAM of the apparatus main body 10 as appropriate.
[0014]
The modeling program PR includes programs for initialization processing, specific area designation processing, resolution conversion processing, image integration processing, correspondence update processing, and other processing.
[0015]
The medium drive device 12 accesses a semiconductor memory HM such as a CD-ROM (CD), a floppy disk FD, a magneto-optical disk, and a compact flash (registered trademark), and other recording media, and reads and writes data or a program. An appropriate drive device is used depending on the type of the recording medium. The above-described modeling program PR can be installed from these recording media. It is also possible to input three-dimensional data DT, image FT, and the like via a recording medium.
[0016]
On the display surface HG of the display device 13, various data described above, three-dimensional data DT, an image FT, an image of a processing process by the modeling program PR, a generated three-dimensional model ML, for example, a three-dimensional model shown in FIG. The model ML1 and other images or data are displayed.
[0017]
The keyboard 14 and the mouse 15 are used not only by the user to make various designations for the image FT and the three-dimensional data DT displayed on the display device 13, but also to input or instruct various data to the device main body 10. Used to give
[0018]
A digital camera for capturing an object from various positions around the object and obtaining an image FT can be connected to the apparatus main body 10. It is also possible to connect a three-dimensional measuring device for photographing an object and inputting its three-dimensional data DT. Such a three-dimensional measuring device measures non-contact three-dimensional data DT of an object by, for example, a light section method. Alternatively, instead of the three-dimensional data DT, data serving as a source for generating the three-dimensional data DT may be output from the three-dimensional measuring device, and the three-dimensional data DT may be obtained by the calculation by the device body 10.
[0019]
Note that the coordinates of each pixel on the image FT obtained by the digital camera can be associated with the position information of each vertex on the polygon mesh PM based on the three-dimensional data DT obtained by three-dimensional measurement. I have. For this purpose, the digital camera and the three-dimensional measuring device are provided with a position and orientation sensor that detects the position and orientation and outputs position and orientation information. Also, the three-dimensional data DT and the image FT can be obtained by the three-dimensional measuring device itself. In that case, the positional relationship between the three-dimensional data DT and the image FT is defined by the internal parameters of the three-dimensional measuring device, or a projection matrix is generated.
[0020]
FIG. 2 is a diagram showing an example of a three-dimensional model ML1 generated by the editing device 1, FIG. 3 is a diagram showing an example of data constituting the three-dimensional model ML1, and FIG. 4 is a table TB1 of the three-dimensional model ML1. It is a figure showing an example.
[0021]
In the three-dimensional model ML1 shown in FIG. 2, the object Q is for a character doll. The three-dimensional model ML1 is obtained by measuring the object Q with a three-dimensional measuring device, and mapping an image FT of the object Q similarly photographed by the three-dimensional measuring device onto the three-dimensional data DT obtained thereby.
[0022]
As shown in FIG. 3, the three-dimensional model ML1 includes a table TB1 indicating the configuration of the three-dimensional model ML1, and all the images FT1 to FT4 mapped to the three-dimensional model ML1. The table TB1 indicates vertices indicating the configuration of the polygons of the three-dimensional model ML1 and their coordinate values, the ID (texture ID) of the image FT to be pasted on each polygon, the coordinate values of the corresponding part in the image FT, and the like.
[0023]
The surface of the three-dimensional model ML1 is divided into a plurality of regions such as a face, a hand, a torso, a back, a foot, and the like.
In FIG. 4, for example, in the face region, one polygon of the region is composed of three vertices (P1, P2, P3), and the polygon uses an image FT1 designated by a texture ID as a texture image. its three coordinate points in the image _{FT1 (x 11, y 11)} (x 12, y 12) (x 13, y 13) portion surrounded by is actually paste. In this way, the configuration of all the polygons in the face area and the image to be pasted thereon are defined. Similarly, the configuration and image of each polygon are defined for the other regions, that is, the hand, the torso, and the like.
[0024]
Since such a three-dimensional model ML1 has a large data amount, the three-dimensional model ML1 is reduced in order to reduce the data amount. Next, an editing process for reducing the three-dimensional model ML1 will be described.
[0025]
5 is a diagram for explaining a method for editing the three-dimensional model ML1, FIG. 6 is a diagram for explaining a method for specifying a specific region TR on the three-dimensional model ML, and FIG. 7 is a diagram for specifying the specific region TR on the image FT. 8 illustrates a method of generating an image FG2 of an area other than the specific area TR, FIG. 9 illustrates an example of the contents of a table TB2 of the reduced three-dimensional model MLS, and FIG. It is a flowchart which shows a process.
[0026]
Referring to FIG. 5, first, in the first stage, a specific region TR is specified for the three-dimensional model ML in preparation for generating a reduced new image FTS. In this case, as the specific region TR, a region in which the image of the surface is composed of high-frequency components, that is, a region composed of a finely changing image, a character region, or the like is designated. However, it is not limited to these.
[0027]
In the present embodiment, the face area of the three-dimensional model ML is specified as the specific area TR. The specification of the specific region TR is performed manually or automatically. When manually specifying the specific region TR, the specific region TR may be specified on the three-dimensional model ML or may be specified on the two-dimensional image FT.
[0028]
That is, in the example shown in FIG. 6, the face area is specified as the specific area TR on the three-dimensional model ML. Here, a polygon included in a range to be specified as the specific region TR is selected. That is, for example, the polygons in the specific area TR are picked up one by one. The set of the picked-up polygons becomes the specified specific area TR.
[0029]
In the example shown in FIG. 7, on the image FT, the face region is designated as a region TRF corresponding to the specific region TR. The region TRF here is rectangular. The image of the area TRF is projected onto the three-dimensional model ML, and polygons on the three-dimensional model ML included in the projected area TRF are picked up. The set of polygons picked up in this manner becomes the specific area TR.
[0030]
In addition, various conventionally known techniques can be used to specify the specific region TR on the three-dimensional model ML or the image FT.
Then, for the polygons selected as the specific area TR, the image FT pasted or assigned to the polygons is projected onto a certain projection plane, for example, a plane or a cylindrical plane. Thus, a new image FG1 is generated. The generated image FG1 is a source of a texture image (image FGS1) for the specific region TR.
[0031]
Next, a non-specific area TS that is an area other than the specific area TR is specified. Here, polygons not selected as the specific area TR are picked up. A set of polygons other than the specific area TR becomes the specified non-specific area TS.
[0032]
Then, as shown in FIG. 8, for the polygons selected as the non-specific area TS, those polygons are projected on the original image FT. On the projected original image FT, continuous polygons PG adjacent to each other on the same image MY are extracted. A rectangular range including the extracted polygon PG is cut out as an image FG2.
[0033]
Thus, the image FG1 for the specific region TR and the images FG2, 3... For the non-specific region TS are obtained. At the time of these processes, the table TB1 is referred to.
[0034]
Next, in the second stage, resolution conversion is performed on these images FG1, FG2,... To generate new reduced images FGS1, 2, 3,.
At the time of the resolution conversion, the ratio of the resolution conversion is different between the image FG1 of the specific region TR and the images FG2, FG3 of the non-specific region TS.
[0035]
In other words, the conversion is performed on the image FG1 in the specific area TR without significantly lowering the resolution. In some cases, the resolution conversion ratio is set to 1, that is, the same resolution. The image FGS1 converted in this manner without significantly lowering the resolution is arranged in a predetermined area of the reduced image FTS. Here, the reduced image FTS is a memory area for generating the reduced image FTS.
[0036]
.. Of the non-specific area TS are converted so as to lower the resolution at a higher rate than in the case of the image FG1. The images FGS2, 3,... Thus converted to have a reduced resolution are arranged side by side in a predetermined area of the reduced image FTS.
[0037]
The ratio of the resolution conversion ratio between the image FGS1 of the specific region TR and the images FGS2, 3... Of the non-specific region TS is, for example, 1: 2, 1: 3, 1: 4, and the like. As a result, the resolution of the image FGS1 is twice, three times, or four times the resolution of the other images FGS2, 3,.
[0038]
Such processing is performed for all the polygons PG of the three-dimensional model ML, and the reduced images FTS are generated by arranging all the converted images FGS1, 2, 3,.
[0039]
In the process of generating such a reduced image FTS, the position coordinates on the reduced image FTS are associated with the polygons PG of the three-dimensional model ML. The table TB2 is updated by such a new association. That is, in the table TB2, for all the polygons PG of the three-dimensional model ML, the coordinate positions of the portion on the reduced image FTS to be attached to each polygon PG are set.
[0040]
As can be seen from the table TB2 shown in FIG. 9, only the reduced image FTS is used as a texture image for all the polygons PG of the three-dimensional model ML. Then, a portion surrounded by three coordinate points in the reduced image FTS is attached to each polygon PG. Thus, the three-dimensional model ML is associated with the reduced image FTS, and the reduced three-dimensional model MLS is generated. Note that the coordinate values shown in FIG. 9 and the coordinate values shown in FIG. 4 are different.
[0041]
10, in the editing process, a specific area TR is designated (# 11), and the specific area TR is projected to generate a new image FG (# 12). The projection is also performed on the non-specific area TS to generate a new image FG (# 13). The resolution conversion is performed such that the ratio of the resolution conversion is different between the image FG1 of the specific region TR and the images FG2, FG3 of the non-specific region TS (# 14). Each of the images FGS whose resolution has been converted is arranged at a predetermined position in the area of the reduced image FTS, thereby generating a reduced image FTS (# 15). The generated reduced image FTS is associated with the three-dimensional model ML or the reduced three-dimensional model MLS.
[0042]
These processes are realized by an initialization process, a specific region designation process, a resolution conversion process, an image integration process, a correspondence update process, or the like by the modeling program PR.
[0043]
As described above, the mapping to the three-dimensional model ML is performed again so that the resolution of the texture image differs between the specific region TR on the three-dimensional model ML and the non-specific region TS that is the other region.
[0044]
Thus, the reduced three-dimensional model MLS is configured by the table TB2 and the reduced image FTS, and the data amount is significantly reduced. In particular, the reduced image FTS becomes one image, the data amount is reduced, and the size is reduced. In addition, in the face region, which is the specific region TR, the image FGS1 whose resolution is not much lower than that of the original image is used as a texture image, so that facial expressions and the like are well expressed, and as a result, the three-dimensional model Are retained.
[0045]
In the above embodiment, the configuration of the polygon PG of the three-dimensional model ML is not changed. However, the configuration of the polygon PG may be changed by reducing the three-dimensional model ML at a predetermined ratio. In that case, the data amount of the three-dimensional data DT is also reduced. Further, the generated reduced three-dimensional model MLS may be converted into an arbitrary size.
[0046]
In the above embodiment, only one face area is specified as the specific area TR, but two or more specific areas TR may be specified. In that case, the ratio of the resolution conversion may be changed according to the specific region TR. Also, the ratio of the resolution conversion may be different for each of the non-specific areas TS.
[0047]
Further, in the above embodiment, when the converted images FGS1, 2, 3,... Are arranged, by associating the images FGS with the polygons PG of the three-dimensional model ML, any position on the reduced image FTS can be obtained. May be arranged. Further, in the above embodiment, the converted image FGS is arranged in one reduced image FTS and collected as one image. However, it is divided into two or more reduced images FTS and arranged, and two or more reduced images FTS are arranged. An image FTS may be generated.
[0048]
In the above embodiment, the type of the object Q, the configuration, the shape, the number of the whole or each part of the editing apparatus 1, the contents and the order of the processing, and the like can be appropriately changed in accordance with the gist of the present invention.
[0049]
【The invention's effect】
According to the present invention, the data amount of the three-dimensional model can be reduced to make it compact, and the characteristic part of the three-dimensional model can be retained.
[Brief description of the drawings]
FIG. 1 is a block diagram of a three-dimensional model editing apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of a three-dimensional model generated by an editing device.
FIG. 3 is a diagram showing an example of data constituting a three-dimensional model.
FIG. 4 is a diagram showing an example of the contents of a table of a three-dimensional model.
FIG. 5 is a diagram for explaining a method of editing a three-dimensional model.
FIG. 6 is a diagram illustrating a method of specifying a specific area on a three-dimensional model.
FIG. 7 is a diagram illustrating a method of specifying a specific area on an image.
FIG. 8 is a diagram illustrating a method of generating an image of an area other than a specific area.
FIG. 9 is a diagram showing an example of the contents of a table of a reduced three-dimensional model.
FIG. 10 is a flowchart illustrating an editing process.
[Explanation of symbols]
1 Editing Apparatus 10 Apparatus Main Body (Specifying Means, Means for Re-Mapping, Resolution Conversion Means, Image Integration Means, Update Means)
ML, MLS 3D model FT image (texture image)
FTS reduced image (new texture image)
TR Specific area TS Non-specific area (other area)

Claims (4)

A method for editing a three-dimensional model to which a texture image is mapped,
Specifying a specific area on the three-dimensional model;
Re-mapping to the three-dimensional model such that the resolution of the texture image is different between the specific region on the three-dimensional model and the other region,
3. A method for editing a three-dimensional model, comprising: An editing device for a three-dimensional model to which a texture image is mapped,
Means for specifying a specific area on the three-dimensional model;
Means for redoing the mapping to the three-dimensional model so that the resolution of the texture image is different between the specific area on the three-dimensional model and the other area,
A three-dimensional model editing apparatus, comprising: An editing device for a three-dimensional model to which a texture image is mapped,
Means for specifying a specific area on the texture image that exists corresponding to the area on the three-dimensional model;
Means for converting the texture image so that the specific region and the non-specific region other than the specific region and corresponding to the region on the three-dimensional model have different resolutions from each other. When,
Image integration means for integrating all resolution-converted texture images as one or more new texture images;
Means for updating the correspondence between the integrated texture image and the three-dimensional model;
A three-dimensional model editing apparatus, comprising: A computer program used for editing a three-dimensional model to which a texture image is mapped,
Specifying a specific area on the three-dimensional model;
Re-mapping to the three-dimensional model such that the resolution of the texture image is different between the specific region on the three-dimensional model and the other region,
A computer program for causing a computer to execute.

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