MODELING METHOD AND APPARATUS

• US 20160140418A1
• Filed: 10/21/2015
• Published: 05/19/2016
• Est. Priority Date: 11/18/2014
• Status: Active Grant

• Current Assignee: Fujitsu Limited, University of Tokyo
• Original Assignee: Fujitsu Limited, University of Tokyo
• Inventors: NAKAGAWA, Machiko, KAZAMA, Masaki, HISADA, Toshiaki, SUGIURA, Seiryo, WASHIO, Takumi, OKADA, Jun-ichi
• Granted Patent: US 10,453,209 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes
• CPC Class Codes: G16H 50/50 for simulation or modelling of medical disorders

Abstract

A disclosed modelling method includes: calculating a first function for generating data of a closed surface that contains plural points representing an annular structure in an object, based on positional information of the plural points; generating data of a first point set representing a boundary of the object, from tomographic image data; detecting data of points which are included in the first point set and located inside the closed surface by using the first function; removing the detected data of points from the data of the first point set to generate data of a second point set; calculating a second function for generating data of a shape of the object using the data of the second point set and data of the plural points; and storing data of the shape of the object, which is generated by using the second function, in the memory.

Claims

1. A modeling apparatus, comprising:

a memory configured to store positional information of a plurality of points; and

a processor coupled to the memory and configured to execute a process, the process comprises;

first calculating a first function for generating data of a closed surface that contains the plurality of points that represent an annular structure in an object, based on the positional information of the plurality of points;

generating data of a first point set that represents a boundary of the object, from data of a plurality of tomographic images in each of which a first area occupied by the object is designated;

detecting data of points which are included in the first point set and located inside the closed surface by using the first function;

removing the detected data of points from the data of the first point set to generate data of a second point set;

second calculating a second function for generating data of a shape of the object using the data of the second point set and data of the plurality of points; and

storing data of the shape of the object, which is generated by using the second function, in the memory.

2. The modeling apparatus as set forth in claim 1, wherein the process further comprises:

third calculating a third function for generating data of a surface that passes through the plurality of points; and

dividing the data of the shape of the object, which is stored in the memory, by the data of the surface generated by using the third function.

3. The modeling apparatus as set forth in claim 1, wherein the first calculating comprises:

first identifying, for each of the plurality of points, data of a third point set that includes a first point separated from the point in a positive direction of a normal for the point by a first distance, a second point separated from the point in the positive direction of the normal by a second distance, a third point separated from the point in the negative direction of the normal by the second distance, a fourth point separated from the point in a positive direction of a binormal for the point by a third distance, and a fifth point separated from the point in a negative direction of the binormal by the third distance; and

first setting a function value for each point included in the third point set to calculate the first function based on the set function values.

4. The modelling apparatus as set forth in claim 1, wherein the second calculating comprises:

second identifying, for each of the plurality of points, data of a fourth point set that includes a sixth point separated from the point in a positive direction of a normal for the point by a fourth distance, and a seventh point separated from the point in a negative direction of the normal by the fourth distance; and

second setting a function value for each point included in the fourth point set, a function value for each of the plurality of points, and a function value for each point included in the second point set to calculate the second function based on the set function values.

5. The modelling apparatus as set forth in claim 2, wherein the third calculating comprises:

third identifying, for each of the plurality of points, data of a fifth point set that includes an eighth point separated from the point in a positive direction of a binormal for the point by a fifth distance, and a ninth point separated from the point in a negative direction of the binormal by the fifth distance; and

third setting a function value for each point included in the fifth point set and a function value for each of the plurality of points to calculate the third function based on the set function values.

6. The modelling apparatus as set forth in claim 1, wherein the detecting comprises:

detecting data of points which are included in the first point set and located inside the closed surface, based on whether or not values of the first function are greater than a predetermined value.

7. The modelling apparatus as set forth in claim 1, wherein the first point set includes points which are included in the first area and adjacent to an area other than the first area, and points which are included in the area other than the first area and adjacent to the first area.

8. A modelling method using a computer including a memory configured to store positional information of a plurality of points and a processor coupled to the memory, the modelling method comprising:

first calculating, by using the processor, a first function for generating data of a closed surface that contains the plurality of points that represent an annular structure in an object, based on the positional information of the plurality of points;

generating, by using the processor, data of a first point set that represents a boundary of the object, from data of a plurality of tomographic images in each of which a first area occupied by the object is designated;

detecting, by using the processor, data of points which are included in the first point set and located inside the closed surface by using the first function;

removing, by using the processor, the detected data of points from the first point set to generate data of a second point set;

second calculating, by using the processor, a second function for generating data of a shape of the object using the data of the second point set and data of the plurality of points; and

storing, by using the processor, data of the shape of the object, which is generated by using the second function, in the memory.

9. A non-transitory computer-readable storage medium storing a program for causing a computer including a memory configured to store positional information of a plurality of points and a processor coupled to the memory to execute a process, the process comprising:

first calculating, by using the processor, a first function for generating data of a closed surface that contains the plurality of points that represent an annular structure in an object, based on the positional information of the plurality of points;

generating, by using the processor, data of a first point set that represents a boundary of the object, from data of a plurality of tomographic images in each of which a first area occupied by the object is designated;

detecting, by using the processor, data of points which are included in the first point set and located inside the closed surface by using the first function;

removing, by using the processor, the detected data of points from the first point set to generate data of a second point set;

second calculating, by using the processor, a second function for generating data of a shape of the object using the data of the second point set and data of the plurality of points; and

storing, by using the processor, data of the shape of the object, which is generated by using the second function, in the memory.