JP2016045641A - Image processing device, image processing method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate a natural 3D model.SOLUTION: A 3D model reception unit 111 of an image processing device 100 accepts an inputted 3D model. An information acquisition unit 112 acquires additional information added to the 3D model. A discrimination unit 113 discriminates whether the accepted 3D model is a 3D model of a natural object or a 3D model of an artifact on the basis of the acquired additional information. A subdivision processing unit 114 subdivides a mesh of the 3D model of a natural model a prescribed number of times in the case where the discrimination unit 113 discriminates that the 3D model is a 3D model of a natural object, and does not subdivide the mesh of a 3D model of an artifact in the case where the discrimination unit discriminates that the 3D model is a 3D model of an artifact.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image processing apparatus, an image processing method, and a program.

In recent years, with the advance of computer graphics (CG) technology, 3D models (hereinafter also referred to as three-dimensional models) produced with polygons are widely used.
This 3D model is generally composed of a set of polygons (polygons) composed of vertices, sides and faces, and the set of polygons is called a mesh.
Regarding the 3D model technique, for example, Non-Patent Document 1 discloses a technique for locally subdividing a mesh of a connection portion in order to smoothly connect 3D models.

Hidefumi Yamada, 2 others, “Subdivision Surface Connection Method Based on Local Refinement”, Art Science Society, November 2000

  By the way, when the mesh of the 3D model is subdivided to obtain a smooth curved surface, there is a problem that it becomes unnatural depending on the 3D model. For example, in the case of an artificially manufactured and built 3D model, if the subdivision process is performed on the 3D model, the original shape is lost and the shape becomes unnatural.

  Accordingly, the present invention has been made in view of the above-described problems, and an object thereof is to provide an image processing apparatus and the like suitable for generating a natural 3D model.

In order to achieve the above object, an image processing apparatus according to the present invention provides:
Accepting means for accepting a three-dimensional model composed of input polygons;
Discriminating means for discriminating whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
Processing means for performing different processing on the three-dimensional model according to the determination result of the determination means;
It is provided with.

In order to achieve the above object, an image processing method of the present invention comprises:
A reception step for receiving a three-dimensional model composed of the input polygons;
A determination step of determining whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
A processing step for performing different processing on the three-dimensional model according to the determination result in the determination step;
It is characterized by including.

In order to achieve the above object, the program of the present invention provides:
Computer
Accepting means for accepting a three-dimensional model composed of input polygons;
A discriminating means for discriminating whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
Processing means for performing different processing on the three-dimensional model according to the determination result of the determination means;
It is made to function as.

  According to the present invention, a natural 3D model can be generated.

It is a block diagram which shows the structure of an image processing apparatus. It is a figure which shows an example of the 3D model of the input ant (ant). It is a figure which shows an example of a dictionary table. It is a figure which shows the 3D model of an ant after performing subdivision once. It is a figure which shows the 3D model of an ant after performing subdivision twice. It is a figure which shows an example of a bounding box. It is a figure which shows typically the spherical body by which the several viewpoint was set on the spherical surface. It is a flowchart which shows an example of the flow of a subdivision process. It is a figure which shows an example of the 3D model of the input slot machine. It is a figure which shows the 3D model of the slot machine after performing subdivision once. It is a figure which shows the 3D model of the slot machine after performing subdivision twice.

Embodiments of the present invention will be described below with reference to the drawings.
As illustrated in FIG. 1, the image processing apparatus 100 includes a control unit 110, a display unit 120, and a storage unit 130. The image processing apparatus 100 performs image processing of a three-dimensional 3D model such as a person, an animal, or a structure arranged in a virtual three-dimensional space.

  The control unit 110 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The CPU of the control unit 110 reads out and executes a 3D model image processing program stored in the ROM, thereby executing each function (3D model reception unit 111, information acquisition unit 112, determination unit 113, subdivision processing). Unit 114, bounding box setting unit 115, viewpoint setting unit 116, viewpoint reception unit 117, rotation unit 118, and line drawing generation unit 119).

The display unit 120 includes a display such as liquid crystal or organic EL (Electroluminescence), and a light source such as a backlight that uniformly illuminates the display. The display unit 120 includes a display screen (screen) 121 that displays a 3D model.
The storage unit 130 is a nonvolatile memory such as an HDD (Hard Disk Drive). The storage unit 130 includes a dictionary table 131 and a viewpoint data storage unit 132. These will be described later.

Next, each function of the control unit 110 will be described.
The 3D model reception unit 111 receives the input 3D model. Specifically, the 3D model reception unit 111 receives a 3D model composed of polygons created by software having a 3D modeling function such as CAD (Computer Aided Design).

  This 3D model is input by the user as a material for generating a line drawing. The method of inputting the 3D model is arbitrary. For example, it may be input from outside the image processing apparatus 100 via a network, or a 3D model produced in the image processing apparatus 100 and stored in the storage unit 130 in advance may be input. The 3D model receiving unit 111 corresponds to a receiving unit.

  FIG. 2 shows an example of the input 3D model. As shown in the figure, the virtual three-dimensional space has a world coordinate system having a width, a height, and a depth by intersecting the X axis, the Y axis, and the Z axis at right angles. In the following description, the input ant 3D model 10 will be described as an example, and will be described separately from a general 3D model as a superordinate concept. Also, in the ant 3D model 10 in the figure, the top and bottom are the same, but the top and bottom are not the same (for example, when the ant is turned upside down and the top and bottom are reversed), the top and bottom are corrected. Keep them consistent.

Returning to FIG. 1, the information acquisition unit 112 acquires incidental information attached to the 3D model. This supplementary information is name information indicating the name of the 3D model in this embodiment. In the case of the ant 3D model 10 illustrated in FIG. 2, the name indicated by the name information is an ant.
In addition, the user may input incidental information together when inputting the 3D model, or may input incidental information when creating the 3D model. In short, there may be incidental information (name information in this embodiment) associated with the input 3D model. The information acquisition unit 112 corresponds to an information acquisition unit.

  Next, the determination unit 113 determines whether the 3D model is a natural 3D model or an artificial 3D model. Specifically, the determination unit 113 determines whether the received 3D model is a natural object 3D model or an artificial object 3D based on a dictionary table 131 indicating whether the name indicated by the name information is a natural object name or an artificial object name. Determine whether it is a model.

Here, the dictionary table 131 is a table in which names and attributes are associated with each other as shown in FIG. The attribute indicates whether an associated name is an artificially manufactured or constructed artificial object or a non-artificial natural object.
For example, in the case of the ant 3D model 10, the name indicated by the name information is ant, and therefore the determination unit 113 refers to the dictionary table 131 to determine that the ant 3D model is a natural 3D model. Note that the determination unit 113 corresponds to a determination unit.

Returning to FIG. 1, the subdivision processing unit 114 performs different processing on the 3D model according to the determination result of the determination unit 113. Specifically, when the determination unit 113 determines that the 3D model is a 3D model of a natural object, the subdivision processing unit 114 performs predetermined processing on the 3D model of the natural object. On the other hand, when it is determined that the 3D model is a 3D model of an artifact, predetermined processing is not performed on the 3D model of the artifact.
For example, the subdivision processing unit 114 performs predetermined processing on the ant 3D model 10 that is determined as a natural 3D model by the determination unit 113.

Here, the predetermined process is a process of subdividing a mesh, which is a set of polygons constituting the 3D model, a predetermined number of times to change the surface of the polygon from a plane to a curved surface. In other words, it is a process of rounding corners in the shape of the 3D model.
In this embodiment, the subdivision processing unit 114 subdivides the mesh of the ant 3D model 10 twice. FIG. 4 shows the ant 3D model 10 after the first subdivision, and FIG. 5 shows the ant 3D model 10 after the second subdivision, respectively. From the figure, it can be seen that the corner of the 3D model 10 of the ant is rounded with each subdivision. The subdivision processing unit 114 corresponds to a processing unit.

  Returning to FIG. 1, the bounding box setting unit 115 sets a bounding box surrounding the 3D model for the 3D model in order to set the viewpoint (viewpoint) and normalize the scale. In the example of FIG. 6, the bounding box 20 surrounding the ant 3D model 10 after being subdivided twice is indicated by a broken line.

  Next, the viewpoint setting unit 116 generates a sphere based on the bounding box 20 and sets a plurality of viewpoints on the surface of the sphere. Specifically, the viewpoint setting unit 116 first generates a sphere having the intersection of two diagonal lines of the bounding box 20 as the center of the sphere and the diagonal length as the diameter of the sphere. Thus, first, a sphere surrounding the ant 3D model 10 is generated. The diameter may be obtained by multiplying the diagonal length by a coefficient according to the scale desired by the user.

  Next, the viewpoint setting unit 116 sets a plurality of viewpoints on the spherical surface based on the position information of each of the plurality of viewpoints stored in the viewpoint data storage unit 132. The position information is information on the position of the viewpoint on the spherical surface, and is registered in advance by the user. The viewpoint setting unit 116 arranges viewpoints on the generated sphere based on this position information, and obtains a sphere 30 in which a plurality of equally spaced viewpoints are set on a spherical surface as schematically shown in FIG. .

  Thereby, a plurality of viewpoints are set on the surface of the sphere 30 corresponding to the size of the received ant 3D model 10, and the coordinates of each of the plurality of viewpoints are determined. Hereinafter, the bounding box 20 surrounding the ant 3D model 10 and the sphere 30 generated based on the ant 3D model 10 will be described separately from the bounding box and the sphere as a superordinate concept.

  As described above, the process up to setting a plurality of viewpoints on the spherical surface is the preprocessing necessary for generating a line drawing from the 3D model. Below, on the premise of this pre-processing, a flow from generation of a line drawing from a 3D model will be described.

Returning to FIG. 1, the viewpoint reception unit 117 receives a viewpoint (target viewpoint) that is a target for generating a line drawing specified by the user. Specifically, the viewpoint reception unit 117 receives a viewpoint as a designated target from among a plurality of viewpoints on the sphere 30 surrounding the ant 3D model 10.
Designation of the viewpoint by the user is performed by an arbitrary method. For example, the user may select a viewpoint to be specified with a mouse or the like, or the coordinates of the viewpoint to be specified may be directly input using a keyboard.

  The number of viewpoints specified by the user may be plural. In addition, if the viewpoints of the desired line drawing are determined from the preprocessing stage, the user may designate a plurality of viewpoints (for example, 100 viewpoints) in advance. This designation can be performed, for example, when the user registers the position information of the viewpoint in the viewpoint data storage unit 132.

  Next, when receiving the target viewpoint, the rotation unit 118 rotates the 3D model while maintaining the top and bottom of the 3D model, and moves the received viewpoint to the center of the display screen 121.

Next, the line drawing generation unit 119 generates a line drawing of the 3D model based on the 3D model viewed from the viewpoint at the center of the display screen 121. The line drawing is a two-dimensional image drawn with only lines, and is generated by an arbitrary method based on the 3D model. For example, the line drawing generation unit 119 generates a line drawing by extracting and tracing the edge of the 3D model.
When there are a plurality of target viewpoints, a line drawing is generated for each of the plurality of viewpoints. Thereby, the line drawing of the 3D model 10 of the ant seen from the several viewpoint is obtained.

  As described above, in the flow from reception of a 3D model to generation of a line drawing described with reference to FIGS. 1 to 7, one feature is a detail performed according to the attribute (natural object / artificial object) of the received 3D model. This is a division process. Therefore, the subdivision processing will be described below with reference to the flowchart of FIG. The image processing apparatus 100 stands by until a 3D model is received (step S11; No). When the 3D model reception unit 111 receives a 3D model (step S11; Yes), the following processing is performed in order.

  The determination unit 113 determines whether the received 3D model is a 3D model of a natural object (step S12). Specifically, the determination unit 113 specifies an attribute associated with the name indicated by the name information acquired by the information acquisition unit 112 with reference to the dictionary table 131, and determines whether the attribute is a 3D model of a natural object. .

  Here, when the received 3D model is a natural 3D model (step S12; Yes), the subdivision processing unit 114 executes subdivision twice on the 3D model (step S13), and ends the process. For example, when the received 3D model is an ant 3D model 10 that is a natural object, the subdivision processing unit 114 executes subdivision of the mesh of the ant 3D model 10 twice (see FIGS. 4 and 5).

  On the other hand, when the received 3D model is not a natural 3D model (step S12; No), that is, when the 3D model is a 3D model of an artifact, the subdivision is not performed on the 3D model of the artifact. The process ends.

  Here, the case where the received 3D model is the 3D model 11 of the slot machine shown in FIG. 9 will be described as an example. The determination unit 113 identifies the attribute associated with the name slot machine indicated by the name information as an artificial object with reference to the dictionary table 131, and determines that the attribute is not a natural object (step S12; No). Then, the subdivision processing unit 114 ends the process without performing subdivision on the mesh of the 3D model 11 of the slot machine.

  Here, a comparative example when the mesh of the 3D model 11 of the slot machine shown in FIG. 9 is subdivided without depending on the subdivision processing of this embodiment will be described with reference to FIGS. FIG. 10 is a diagram showing a 3D model of the slot machine 11 after the subdivision is performed once, and FIG. 11 is a diagram showing a 3D model of the slot machine 11 after the subdivision is performed twice. As is clear from these comparative examples, when subdivision is repeated for a 3D model of an artifact, the original shape is lost and the shape becomes unnatural.

  Based on the comparative example described above, in this embodiment, the image processing apparatus 100 includes the determination unit 113 and the subdivision processing unit 114, so that the received 3D model is a natural 3D model or an artificial 3D model. The model is discriminated, and mesh subdivision is performed only in the case of a 3D model of a natural object.

  For this reason, since a smooth curved surface can be obtained by subdividing the mesh for a natural 3D model, a more natural 3D model can be generated. Further, since the mesh is not subdivided in the case of the 3D model of the artifact, the accepted 3D model of the artifact can be left in a natural shape. Therefore, a natural 3D model can be obtained for both natural and artificial objects.

  Further, according to the image processing apparatus 100, a line drawing generated based on a natural 3D model (a line drawing with many curves for a natural object and a line drawing with many straight lines for an artifact) can be stored in a database. Therefore, the accuracy of line drawing search can be improved when the user later searches the database using a line drawing sketched or a photograph taken by the user as a query. This is because sketches and photographs usually have many curves for natural objects and many straight lines for artifacts.

  Although the description of the embodiment has been completed, the specific configuration of the image processing apparatus 100 and the details of the subdivision processing illustrated in FIG. 8 are not limited to those described in the above embodiment.

(Modification)
In the embodiment described above, the determination unit 113 uses the name information that is incidental information of the 3D model in order to determine whether the received 3D model is a natural object or an artificial object, but is not limited thereto. For example, the incidental information can be label information indicating whether the 3D model is a natural 3D model or an artificial 3D model. Thereby, the discrimination | determination part 113 can discriminate | determine whether it is a natural thing or an artifact based on this label information. For this reason, it is not necessary to refer to the dictionary table 131 and the like, so that the processing load of the image processing apparatus 100 can be reduced.

  Further, the determination unit 113 may determine whether the object is a natural object or an artificial object based on the line segment information constituting the received 3D model without depending on the incidental information. For example, the discriminating unit 113 may discriminate an artificial object as long as there are many orthogonal angles between straight lines, or a database of characteristic line segment information found in an artificial object / natural object in advance, and matching with it. It may be determined whether the object is a natural object or an artificial object.

  In the above-described embodiment, the subdivision processing unit 114 performs subdivision twice. However, the present invention is not limited to this. For example, if there is an optimum number of times according to a group (plants, animals, etc.) included in a natural object, it is good to perform subdivision for a different optimum number for each group.

  Further, the subdivision processing unit 114 may perform a smoothing process for smoothing the unevenness generated on the surface of the 3D model in addition to the subdivision of the mesh. For example, this smoothing process can be performed after receiving a 3D model in the subdivision process shown in FIG. Thereby, since the noise of the 3D model can be removed, a more natural 3D model can be obtained without increasing the number of polygons.

  Further, the above-described image processing apparatus 100 can be applied to various apparatuses that perform 3D model image processing. For example, the present invention can be applied to a PC (Personal Computer). Note that the present invention is not limited to a PC, and any apparatus having a display screen 121 can be applied to, for example, a camera or a composite printer. If a plurality of line drawings with different viewpoints are stored in a database in the storage unit of the composite printer, it is possible to read the paper sketched by the user with a reading unit such as a scanner and search the database for line drawings that match the read sketch. .

Each function of the image processing apparatus 100 of the present invention can also be implemented by a computer such as a normal PC.
Specifically, in the above-described embodiment, the 3D model image processing program has been described as being stored in advance in the ROM of the control unit 110. However, the programs for realizing the functions of the respective units in FIG. 1 can be read by a computer such as a flexible disk, a CD-ROM (Compact Disc Read Only Memory), a DVD (Digital Versatile Disc), and an MO (Magneto-Optical Disc). You may comprise the computer which can implement | achieve the function of each above-mentioned part by storing in a recording medium, distributing, and installing the program in a computer.
Further, the program may be stored in a disk device or the like of a server device on a communication network such as the Internet so that, for example, a computer can download it.

  As mentioned above, although embodiment of this invention was described, this embodiment is only an illustration and does not limit the technical scope of this invention. The present invention can take various other embodiments, and various modifications such as omission and replacement can be made without departing from the gist of the present invention. These embodiments and modifications thereof are included in the invention described in the claims and the equivalent scope thereof. The invention described in the scope of claims at the beginning of the present application will be appended.

(Appendix 1)
Accepting means for accepting a three-dimensional model composed of input polygons;
Discriminating means for discriminating whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
Processing means for performing different processing on the three-dimensional model according to the determination result of the determination means;
An image processing apparatus comprising:

(Appendix 2)
When the determining means determines that the three-dimensional model is a three-dimensional model of a natural object, the processing means performs a predetermined process on the three-dimensional model of the natural object, and the three-dimensional model becomes a three-dimensional model of an artifact. The image processing apparatus according to appendix 1, wherein the predetermined processing is not performed on the three-dimensional model of the artifact when it is determined that

(Appendix 3)
The image processing apparatus according to appendix 2, wherein the predetermined process is a process of making a surface of a polygon constituting the three-dimensional model of the natural object a curved surface.

(Appendix 4)
The image processing apparatus according to appendix 3, wherein the process of making the curved surface is performed by subdividing a mesh of the three-dimensional model of the natural object a predetermined number of times.

(Appendix 5)
Comprising information acquisition means for acquiring incidental information incidental to the three-dimensional model,
The discriminating means discriminates whether the three-dimensional model is a natural three-dimensional model or an artificial three-dimensional model based on the incidental information acquired by the information acquiring means. 5. The image processing device according to any one of 4.

(Appendix 6)
The incidental information is name information indicating the name of the three-dimensional model,
Based on the dictionary information indicating whether the name indicated by the name information is the name of a natural object or the name of an artifact, whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact, The image processing apparatus according to appendix 5, characterized in that

(Appendix 7)
The incidental information is label information indicating whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact.
6. The image processing apparatus according to appendix 5, wherein the determination unit determines whether the three-dimensional model is a natural three-dimensional model or an artificial three-dimensional model based on the label information.

(Appendix 8)
The discriminating means discriminates whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact based on line segment information constituting the three-dimensional model. 5. The image processing device according to any one of 4.

(Appendix 9)
Smoothing irregularities on the surface of the polygon constituting the three-dimensional model received by the receiving means;
The image processing apparatus according to any one of appendices 1 to 8, characterized in that:

(Appendix 10)
A reception step for receiving a three-dimensional model composed of the input polygons;
A determination step of determining whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
A processing step for performing different processing on the three-dimensional model according to the determination result in the determination step;
An image processing method comprising:

(Appendix 11)
Computer
Accepting means for accepting a three-dimensional model composed of input polygons;
A discriminating means for discriminating whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
Processing means for performing different processing on the three-dimensional model according to the determination result of the determination means;
Program to function as.

DESCRIPTION OF SYMBOLS 10 ... 3D model of an ant (11), 11 ... 3D model of a slot machine, 20 ... Bounding box, 30 ... Sphere, 100 ... Image processing apparatus, 110 ... Control part, 111 ... 3D model reception part, 112 ... Information acquisition part , 113: discriminating unit, 114: subdivision processing unit, 115 ... bounding box setting unit, 116 ... viewpoint setting unit, 117 ... viewpoint accepting unit, 118 ... rotation unit, 119 ... line drawing generation unit, 120 ... display unit, 121 ... Display screen, 130 ... storage unit, 131 ... dictionary table, 132 ... viewpoint data storage unit

Claims (11)

Accepting means for accepting a three-dimensional model composed of input polygons;
Discriminating means for discriminating whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
Processing means for performing different processing on the three-dimensional model according to the determination result of the determination means;
An image processing apparatus comprising:   When the determining means determines that the three-dimensional model is a three-dimensional model of a natural object, the processing means performs a predetermined process on the three-dimensional model of the natural object, and the three-dimensional model becomes a three-dimensional model of an artifact. 2. The image processing apparatus according to claim 1, wherein the predetermined processing is not performed on the three-dimensional model of the artifact when it is determined that   The image processing apparatus according to claim 2, wherein the predetermined process is a process of making a surface of a polygon constituting the three-dimensional model of the natural object a curved surface.   The image processing apparatus according to claim 3, wherein the process of making the curved surface is performed by subdividing a mesh of the three-dimensional model of the natural object a predetermined number of times. Comprising information acquisition means for acquiring incidental information incidental to the three-dimensional model;
2. The discriminating unit discriminates whether the three-dimensional model is a natural three-dimensional model or an artificial three-dimensional model based on the incidental information acquired by the information acquiring unit. 5. The image processing device according to any one of items 4 to 4. The incidental information is name information indicating the name of the three-dimensional model,
Based on the dictionary information indicating whether the name indicated by the name information is the name of a natural object or the name of an artifact, whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact, The image processing apparatus according to claim 5, wherein: The incidental information is label information indicating whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact.
The image processing apparatus according to claim 5, wherein the determination unit determines whether the three-dimensional model is a natural three-dimensional model or an artificial three-dimensional model based on the label information.   2. The discrimination means discriminates whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact based on line segment information constituting the three-dimensional model. 5. The image processing device according to any one of items 4 to 4. Smoothing irregularities on the surface of the polygon constituting the three-dimensional model received by the receiving means;
The image processing apparatus according to claim 1, wherein the image processing apparatus is an image processing apparatus. A reception step for receiving a three-dimensional model composed of the input polygons;
A determination step of determining whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
A processing step for performing different processing on the three-dimensional model according to the determination result in the determination step;
An image processing method comprising: Computer
Accepting means for accepting a three-dimensional model composed of input polygons;
A discriminating means for discriminating whether the three-dimensional model is a three-dimensional model of a natural object or a three-dimensional model of an artifact;
Processing means for performing different processing on the three-dimensional model according to the determination result of the determination means;
Program to function as.

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