Bird's-eye view forming method, map display apparatus and navigation system

• US 6,346,942 B1
• Filed: 02/04/2000
• Issued: 02/12/2002
• Est. Priority Date: 04/20/1995
• Status: Expired due to Term

• Current Assignee: Clarion Co., Ltd. (Faurecia SA)
• Original Assignee: Hitachi, Ltd., Xanavi Informatics Corporation (Hitachi, Ltd.), Nissan Motor Co., Ltd.
• Inventors: Endo, Yoshinori, Satake, Hiroyuki, Watanabe, Masaki, Shojima, Hiroshi, Hirano, Motoki, Fujiwara, Toshio, Kishi, Norimasa
• Primary Examiner(s): Zimmerman, Mark
• Assistant Examiner(s): MANCUSO, HUEDUNG XUAN CAO
• Application Number:
  US09/497,932
• Time in Patent Office: 739 Days
• Field of Search: 345/427, 345/418, 345/357, 345/133, 345/139, 345/421, 345/419
• US Class Current: 345/427
• CPC Class Codes: G01C 21/3635 Guidance using 3D or perspective road maps
• CPC Class Codes: G01C 21/367 Details, e.g. road map scale, orientation, zooming, illumination, level of detail, scrolling of road map or positioning of current position marker
• CPC Class Codes: G01C 21/3673 Labelling using text of road map data items, e.g. road names, POI names
• CPC Class Codes: G09B 29/106 using electronic means

Abstract

In a navigation system using a bird'"'"'s-eye view display mode, map data on a plan view map are subjected to a perspective projection conversion to obtain drawing data on a bird'"'"'s-eye view map. In this case, an input of the position of a view point is accepted, and a projection plane for a bird'"'"'s-eye view is determined on the basis of the coordinates of a current position and a destination and the position of the view point so that the display positions of the two points which have been subjected to perspective-projection conversion are coincident with predetermined positions. Alternatively, an input of a scale is accepted, and the position of the view point and the projection plane are determined on the basis of the coordinates of the two points and the scale so that the display positions of the two points after the perspective projection conversion are coincident with predetermined positions and the drawing scale is coincident with the input scale. Or, as a further alternative, an input of the projection angle is accepted, and the projection plane is determined on the basis of the projection angle and the position of the view point.

Claims

1. A map display apparatus comprising:

an image display device;

storage means for storing map data therein;

means for displaying a plan view based on said map data on said image display device;

means for displaying a birds'"'"' eye view based on said map data on said image display device; and

a switching means for switching a display of said image display device to said plan view if said birds'"'"' eye view is displayed on said display device when accepting designation of a point on a map.

2. A map display apparatus comprising:

an image display device;

storage means for storing map data therein;

map drawing means for displaying a map of plan view and a map of birds'"'"' eye view prepared based on said map data by switching these maps; and

point designation accepting means for accepting designation of a point on said map;

said point designation accepting means accepting said designation in a state where said plan view is displayed on said image display device.

3. A map display apparatus according to claim 2, wherein said map drawing means, if said birds'"'"' eye view is displayed on the image display device when accepting said designation, switches the display of said image display device from said birds'"'"' eye view to said plan view.

4. A process unit for a map display apparatus comprising:

means for displaying a plan view based on map data;

means for displaying a birds'"'"' eye view based on said map data; and

a switching means for switching the display of said image display device to said plan view, if said birds'"'"' eye view is displayed on said image display device when accepting designation of a point on the map.

5. A map display method comprising a step of accepting designation of a point on a map, wherein a display of an image display device is switched to a plan view if a birds'"'"' eye view is displayed on said image display device.

6. A map display method comprising:

point designation accepting step for accepting designation of a point on a map; and

map drawing step of displaying a map of plan view and a map of birds'"'"' eye view prepared based on map data by switching these maps;

wherein, said designation is accepted in a state where said plan view is displayed on said image display device in said point designation accepting step.

7. A map display apparatus according to claim 6, wherein if said birds'"'"' eye view is displayed on said image display device, the display of the image display device is switched to said plan view in said map drawing step.

8. A navigation system comprising:

an image display device;

an input device;

map storage means for storing map data therein;

means for displaying a plan view based on said map data on said image display device;

means for displaying a birds'"'"' eye view based on said map data on said image display device; and

a switching means for switching, if said birds'"'"' eye view is displayed on said display device, the display of said image display device to said plan view when accepting designation of a point on a map.

9. A map display apparatus comprising:

a display device;

storage means for storing therein character string data, position data indicative of a position for disposing said character string, and map data; and

display means for displaying a birds'"'"' eye view on said display device by perspectively projecting said map data;

wherein said display means displays said character string on said birds'"'"' eye view at a position as indicated by said position data that has been perspectively projected.

10. A map display apparatus comprising:

a display device;

storage means for storing therein character string data, position data indicative of a position for disposing said character string, and map data; and

display means for displaying a birds'"'"' eye view prepared by using said map data on said display device;

wherein said display means displays said character string on said birds'"'"' eye view.

11. A processing unit for map display apparatus comprising:

reading means for reading character string data, position data indicative of a position for disposing said character string, and map data; and

map drawing means for perspectively projecting said map data to output a map of birds'"'"' eye view;

wherein said display means disposes said character string on said birds'"'"' eye view at a position as indicated by the position data that has been perspectively projected.

12. A map display method in which character data, position data indicative of a position for disposing said character string and a map data are read and said map data is perspectively projected for displaying a birds'"'"' eye view on a display device;

wherein said character data is not perspectively projected.

13. A map display apparatus comprising:

a display device;

map storage means for storing map data and character string data; and

map drawing means for displaying an image of map on said display device by using said map data;

wherein

said map storage means stores, as said character data, vector data for recognizing a position of the character string and image data for recognizing an image of said character strings;

said map drawing means perspectively projects coordinate data included in said map data to produce drawing data for a birds'"'"' eye view onto a predetermined projection plane with a view point at a predetermined position, while the perspective projection is not performed as to said image data.

14. A map display method for displaying a map of a birds'"'"' eye view on a display device by perspectively projecting map data, wherein a character string is displayed on said birds'"'"' eye view at a position as indicated by position data that has been perspectively projected.

15. A navigation system comprising:

a display device;

storage means for storing character string data, position data indicative of a position for disposing said character string, and map data; and

a display means for displaying a map of a birds'"'"' eye view on said display device by perspectively projecting said map data;

wherein said display means displays said character string on said birds'"'"' eye view at a position as indicated by said position data that has been perspectively projected.

16. A map display apparatus comprising:

a display device;

map storage means for storing map data an character string data;

map drawing means for displaying an image of a map on said display device by using said map data;

wherein

said map storage means stores, as said character data, position data for recognizing a position of the character string and image data of said character strings;

said map drawing means comprises perspective projection means for perspectively projecting coordinate data included in said map data to produce drawing data for a birds'"'"' eye view onto a predetermined projection plane with a view point at a predetermined position; and

said perspection projection means perspectively projects said position data of the character data while skipping the perspective projection as to said image data of said character string.

17. A map display apparatus comprising:

a display device;

map storage means for storing map data and character string data;

map drawing means for displaying an image of a map on said display device by using said map data;

wherein said map drawing means excludes character data from drawing data, if it is not a drawing target, among those character data corresponding to a position to be contained in said map.

18. A map display apparatus according to claim 17, wherein said drawing means determines said drawing target among said character string data by comparing a height of display position from a bottom side of display screen with a predetermined reference value.

19. A map display apparatus according to claim 17, wherein at least a part of said character string data has a preliminarily defined attribute and said drawing means determines said drawing target that will fit to an attribute preliminarily determined for respective display regions of the display screen of said display device, among said character string data and the character strings that will not fit to the attribute will be excluded from said drawing target.

20. A map display apparatus comprising:

a display device;

map storage means for storing map data therein; and

map drawing means for preparing drawing data of a map using said map data to display it on said display screen;

wherein said map drawing means comprises;

means for changing an angle of a projection plane in accordance with a distance between two predetermined points contained in said map data; and

perspective projecting means for perspectively projecting said map data to produce said drawing data of a birds'"'"' eye view on said projection plane.

21. A map display apparatus according to claim 20, wherein said means for changing the angle of said projection plane reduces the projection angle as the distance between said two points is shorter.

22. A map displaying method for displaying a map of birds'"'"' eye view on a display screen by perspectively projecting map data, wherein if a display height of a character string from the bottom side of said display device is more than a predetermined reference value, said character string is not to be a drawing target.

23. A map display method for displaying a map of birds'"'"' eye view on a display screen by perspectively projecting map data, wherein a character string at a location whose distance from a view point is longer than a predetermined reference value is not to be a drawing target.