Three-dimensional terrain-information generating system and method, and computer program therefor

• US 7,133,539 B2
• Filed: 03/12/2003
• Issued: 11/07/2006
• Est. Priority Date: 03/27/2002
• Status: Expired due to Fees

• Current Assignee: Image Processing Technologies, LLC (General Patent Corporation)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Ohto, Yasunori
• Primary Examiner(s): Mehta, Bhavesh M.
• Assistant Examiner(s): Strege, John B
• Application Number:
  US10/385,492
• Publication Number:
  US 20040027344A1
• Time in Patent Office: 1,336 Days
• Field of Search: 382/113, 382/154, 702/5
• US Class Current: 382/113
• CPC Class Codes: G01C 21/3826 Terrain data
• CPC Class Codes: G01C 21/3867 Geometry of map features, e.g. shape points, polygons or for simplified maps
• CPC Class Codes: G06F 30/13 Architectural design, e.g. computer-aided architectural design [CAAD] related to design of buildings, bridges, landscapes, production plants or roads
• CPC Class Codes: G06T 17/05 Geographic models

Abstract

A three-dimensional terrain-information generating system extracts a road region from altitude information arranged on a two-dimensional plane and adjusts the position and scale by matching the road region with a building/road map. Altitude information of a road region with a width that is greater than or equal to a preset width is obtained from the building/road map, and the obtained altitude information is arranged in a three-dimensional space. Ribbon forms that may intersect one another at a plurality of points are generated. Altitude information of a region such as a park that is almost free from the effects of a building on the three-dimensional terrain is obtained from the building/road map. Subsequently, a surface including such altitude information is created, thereby generating three-dimensional terrain data.

Claims

1. A three-dimensional terrain-information generating system for generating three-dimensional terrain information by mapping elevation-data including altitude information that is mapped onto a two-dimensional plane onto building/road map information and by removing effects of a building, comprising:

a flow analyzer that extracts a flow portion from the elevation-data, said flow portion including elevation data for a long area having a defined width and smoothly changing altitude information;

a matching unit that receives the extracted flow portion and that matches coordinates of the elevation-data with coordinates on a building/road map;

a reference region obtaining unit that obtains a reference region for creating three-dimensional terrain data from the elevation-data; and

a surface fitting unit that performs the fitting of a surface so that the surface includes the reference region on a face thereof.

2. The three-dimensional terrain-information generating system according to claim 1, wherein the flow analyzer extracts, from the elevation-data, a region having altitude information that indicates a long, narrow, and gently winding region and that changes smoothly and continuously as the flow portion.

3. The three-dimensional terrain-information generating system according to claim 1, wherein the flow analyzer obtains a road region by generating an image to which pixel values corresponding to the altitude information are mapped, decomposing the image into frequency components by a Fourier transform, extracting a frequency component corresponding to the road region, performing an inverse Fourier transform, and extracting contours of the road region.

4. The three-dimensional terrain-information generating system according to claim 1, wherein the matching unit obtains a transform from the building/road map information to the elevation-data by matching the flow portion extracted by the flow analyzer with a road region included in the building/road map information, obtains the altitude of a region other than a building-located region from the altitude information included in the elevation-data corresponding to the building/road map, and performs a surface approximation using the transform.

5. The three-dimensional terrain-information generating system according to claim 1, wherein the reference region obtaining unit extracts a region including a park that is free from the effects of the building as the reference region.

6. A three-dimensional terrain-information generating system for generating three-dimensional terrain information by mapping elevation-data including altitude information that is mapped onto a two-dimensional plane onto building/road map information and by removing effects of a building, comprising:

a flow analyzer that extracts a flow portion from the elevation-data;

a matching unit that receives the extracted flow portion and that matches coordinates of the elevation-data with coordinates on a building/road map;

a reference region obtaining unit that obtains a reference region for creating three-dimensional terrain data from the elevation-data; and

a surface fitting unit that performs the fitting of a surface so that the surface includes the reference region on a face thereof,

wherein the surface fitting unit generates a surface including the reference region by an approximation of a Non-Uniform Rational B-Spline (NURBS) surface, and

wherein the surface fitting unit adjusts the NURBS surface by minimizing a square error of NURBS parameters, and, when the NURBS surface cannot be adjusted, tessellates the NURBS surface into smaller sections.

7. A three-dimensional terrain-information generating method for generating three-dimensional terrain information by mapping elevation-data including altitude information that is mapped onto a two-dimensional plane onto building/road map information and by removing effects of a building, comprising:

a flow analyzing step of extracting a flow portion from the elevation-data, said flow portion including elevation data for a long area having a defined width and smoothly changing altitude information;

a matching step of receiving the extracted flow portion and matching coordinates of the elevation-data with coordinates on a building/road map;

a reference region obtaining step of obtaining a reference region for creating three-dimensional terrain data from the elevation-data; and

a surface fitting step of performing the fitting of a surface so that the surface includes the reference region on a face thereof.

8. The three-dimensional terrain-information generating method according to claim 7, wherein, in the flow analyzing step, a region having altitude information that indicates a long, narrow, and gently winding region and that changes smoothly and continuously is extracted as the flow portion from the elevation-data.

9. The three-dimensional terrain-information generating method according to claim 7, wherein, in the flow analyzing step, a road region is obtained by generating an image to which pixel values corresponding to the altitude information are mapped, decomposing the image into frequency components by a Fourier transform, extracting a frequency component corresponding to the road region, performing an inverse Fourier transform, and extracting contours of the road region.

10. The three-dimensional terrain-information generating method according to claim 7, wherein, in the matching step, a transform from the building/road map information to the elevation-data is obtained by matching the flow portion extracted in the flow analyzing step with a road region included in the building/road map information, the altitude of a region other than a building-located region is obtained from the altitude information of the elevation-data corresponding to the building/road map, and a surface approximation is performed using the transform.

11. The three-dimensional terrain-information generating method according to claim 7, wherein, in the reference region obtaining step, a region including a park that is free from the effects of the building is extracted as the reference region.

12. The three-dimensional terrain-information generating method according to claim 11, wherein, in the surface fitting step, a surface including the reference region is generated by an approximation of a NURBS surface.

13. A three-dimensional terrain-information generating method for generating three-dimensional terrain information by mapping elevation-data including altitude information that is mapped onto a two-dimensional plane onto building/road map information and by removing effects of a building, comprising:

a flow analyzing step of extracting a flow portion from the elevation-data;

a matching step of receiving the extracted flow portion and matching coordinates of the elevation-data with coordinates on a building/road map;

a reference region obtaining step of obtaining a reference region for creating three-dimensional terrain data from the elevation-data; and

a surface fitting step of performing the fitting of a surface so that the surface includes the reference region on a face thereof, wherein, in the surface fitting step, the NURBS surface is adjusted by minimizing a square error of NURBS parameters, and, when the NURBS surface cannot be adjusted, the NURBS surface is tessellated into smaller sections.

14. A computer program written in a computer readable format to perform, on a computer system, the processing of generating three-dimensional terrain information by mapping elevation-data including altitude information that is mapped onto a two-dimensional plane onto building/road map information and by removing effects of a building, comprising:

a flow analyzing step of extracting a flow portion from the elevation-data, said flow portion including elevation data for a long area having a defined width and smoothly changing altitude information;

a matching step of receiving the extracted flow portion and matching coordinates of the elevation-data with coordinates on a building/road map;

a reference region obtaining step of obtaining a reference region for creating three-dimensional terrain data from the elevation-data; and

a surface fitting step of performing the fitting of a surface so that the surface includes the reference region on a face thereof.