POSITIONING SYSTEM

• US 20130188837A1
• Filed: 09/26/2011
• Published: 07/25/2013
• Est. Priority Date: 10/06/2010
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Takahashi, Katsuhiko
• Granted Patent: US 9,104,702 B2
• Time in Patent Office: Days
• US Class Current: 382/103
• CPC Class Codes: G01C 21/20 Instruments for performing navigational calculations G01C21/24, G01C21/26 take precedence
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G06F 16/29 Geographical information databases
• CPC Class Codes: G06F 16/5838 using colour
• CPC Class Codes: G06F 16/5854 using shape and object relationship
• CPC Class Codes: G06T 11/00 2D [Two Dimensional] image generation
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 7/74 involving reference images or patches

Abstract

An object of the present invention is to provide a positioning system which makes it possible to perform positioning processing in a positioning target mobile object with a smaller calculation amount.

A scenery image database according to an aspect of the present invention is characterized by comprising a plurality of scenery image data and image acquisition locations at which the scenery image data have been acquired are correlated with each other and stored, wherein each of the plurality of scenery image data include a feature amount of a feature point corresponding to a thing other than a thing of which a location or a shape is unlikely to be kept as it is on the real world during a period larger than or equal to a predetermined period.

Claims

1. A scenery image database comprising a plurality of scenery image data and image acquisition locations at which the plurality of the scenery image data have been acquired are correlated with each other and stored,

wherein each of the plurality of the scenery image data include a feature amount of a feature point corresponding to a thing other than a thing of which a location or a shape is unlikely to be kept as it is on the real world during a period larger than or equal to a predetermined period.

2. The scenery image database according to claim 1, wherein the thing of which a location or a shape is unlikely to be kept as it is on the real world during a period larger than or equal to a predetermined period is a vehicle.

3. The scenery image database according to claim 1 wherein the thing of which a location or a shape is unlikely to be kept as it is on the real world during a period larger than or equal to a predetermined period is a person.

4. A database building apparatus comprising;

the scenery image database according to claim 1,

first imaging unit which takes a scenery image,

location information acquisition unit which acquires current location information,

first feature point extraction unit which extracts feature amounts of corresponding feature points from the scenery image acquired by the first imaging unit,

future variable area extraction unit which extracts an area corresponding to a thing of which a location or a shape is unlikely to be kept as it is on the real world during a period larger than or equal to a predetermined period from the scenery image acquired by the first imaging unit, and

scenery image database building unit which stores a feature amount of a feature point extracted by the first imaging unit except a feature point that is extracted from the area extracted by the future variable area extraction unit into the scenery image database, and the feature amount and the current location information are correlated with each other.

5. The database building apparatuses according to claim 4, wherein the first imaging unit takes an image not only an image of a wavelength band included in a viewable light region but also an image of a wavelength band not included in the viewable light region, and

the future variable area extraction unit extracts an area corresponding to a plant from the image acquired by the first imaging unit.

6. A positioning target apparatus comprising;

the scenery image database according to claim 1,

second imaging unit which takes an image a scenery image,

second feature point extraction unit which extracts feature amounts of corresponding feature points from the scenery image acquired by the second imaging unit, and

image-collation and location-identification unit which collates the feature amounts of the corresponding feature points extracted by the second feature point extraction unit and the scenery image database, and thereby identify a current location of the positioning target mobile object.

7. The positioning target apparatus according to claim 6, further comprising approximate location acquisition unit which acquires a current approximate location of the positioning target apparatus,

wherein the image-collation and location-identification unit performs image collation by using only scenery image data which is among the scenery image data stored in the scenery image database, and the scenery image data has been created at a location around the approximate location by the positioning target apparatus.

8. A positioning system comprising;

the database building apparatus according to claim 1, and

the position target apparatus according to claim 6,

wherein the scenery image database of the positioning target apparatus has the same content as a content of the scenery image database which has been built by the database building apparatus.

9. The positioning system according to claim 8, further comprising;

a server apparatus which includes scenery-image-database inside server-apparatus downloading unit that transfers a scenery image data in the scenery image database, which the scenery image data is correlated with a location information around a location indicated by the location information upon reception of a request from the positioning target mobile object for transfer of location information and scenery image data,

wherein the positioning target mobile object further includes approximate location acquisition unit which acquires an approximate location of the positioning target mobile object, and

scenery-image-database on positioning-target-mobile-object downloading unit which acquires scenery image data in the scenery image database, and which is correlated with a location information around a location indicated by the approximate location information by transmitting the request for transfer of location information and scenery image data to the scenery-image-database inside server-apparatus downloading unit, and

wherein the image-collation and location-identification unit collates the scenery database acquired by the scenery image database downloading unit and the feature amounts of the corresponding feature points acquired by the second feature point acquisition unit, and thereby identifies the current location.

10. A database building method comprising;

taking a scenery image,

acquiring current location information,

extracting feature amounts of corresponding feature points from the scenery image, and

extracting an area which corresponds to an object of which a location or a shape is likely to vary in future in the real world from the scenery image.

11. The database building method according to claim 10,

wherein not only an image of a wavelength band included in a viewable light region but also an image of a wavelength band not included in the viewable light region is taken, and

an area corresponding to a plant is extracted from the scenery image data.

12. A non-transitory computer-readable storage medium for storing a scenery image database building program which can be executed on a computer comprising the steps of;

a first imaging step of taking a scenery image,

a location information acquisition step of acquiring current location information,

a first feature point extraction step of extracting feature amounts of corresponding feature points from the scenery image acquired by the first imaging unit, and

a future variable area extraction step of extracting an area corresponding to an object of which a location or a shape is likely to vary in the real world from the scenery image data acquired by the first imaging unit.