Method and apparatus for geographic shape preservation for identification

• US 20040030492A1
• Filed: 03/06/2003
• Published: 02/12/2004
• Est. Priority Date: 08/07/2002
• Status: Active Grant

• Current Assignee: HRL Laboratories LLC (The Boeing Co.)
• Original Assignee: HRL Laboratories LLC (The Boeing Co.)
• Inventors: Fox, Jason, Daily, Michael J.
• Granted Patent: US 6,847,888 B2
• Time in Patent Office: Days
• US Class Current: 701/208
• CPC Class Codes: G06T 11/00 2D [Two Dimensional] image generation
• CPC Class Codes: G06T 3/40 Scaling of whole images or parts thereof, e.g. expanding or contracting
• CPC Class Codes: G06T 7/12 Edge-based segmentation

Abstract

A method for transforming a map based on associated geospatial data. A map is segmented into logical segments representing map-based entities. The geospatial data is then associated with the logical segments. The logical segments are scaled based upon the associated data. The logical segments are then repositioned to avoid overlapping other logical segments and a new map display based on the scaled and repositioned logical segments is provided.

Claims

1. A method for enhancing the display of geospatially-based data on a map, wherein said geospatially-based data is associated with map-based entities, said method comprising the steps of:

(a) specifying a hierarchy for the map-based entities shown on a map;

(b) segmenting the map into logical segments based on the hierarchy of map-based entities;

(c) associating the geospatially-based data with corresponding logical segments;

(d) calculating a corresponding scale factor for each logical segment;

(e) scaling each logical segment according to the corresponding scale factor;

(f) repositioning each logical segment to minimize intersections between each logical segment and any other logical segment; and

(g) displaying a map of the scaled and repositioned logical segments.

2. The method of claim 1, wherein each corresponding logical segment comprises an area of pixels and the step of associating the geospatially-based data comprises linearly registering the geospatially-based data to one or more pixels within the corresponding logical segment.

3. The method of claim 2, wherein the step of calculating the corresponding scale factor comprises determining a corresponding segment density factor based on the ratio of the number of pixels within the corresponding logical segment to which geospatially-based data has been registered to the total number of pixels in the area of pixels for the corresponding logical segment.

4. The method of claim 3, wherein the step of scaling each logical segment comprises increasing the area of pixels for the corresponding logical segment if the corresponding scale factor is greater than a specified value and decreasing the area of pixels for the corresponding logical segment if the corresponding scale factor is less than a specified value.

5. The method of claim 1, further comprising repeating steps (d) through (f) until no logical segment intersects any other logical segment.

6. The method of claim 1, wherein the step of segmenting the map into logical segments comprises segmenting raster imagery with vector maps to provide logical segments comprising areas of pixels.

7. The method of claim 1, wherein every logical segment has a single parent segment and the step of repositioning each logical segment comprises repositioning each logical segment in relation to a center of mass of the parent segment.

8. The method of claim 1 wherein the corresponding scale factor comprises at least one factor calculated from the group of factors consisting of data importance, location, political boundaries, geographic features, and display space.

9. A computer-readable medium having computer-executable instructions for performing the method according to claim 1.

10. A computer system using computer-executed instructions for performing the method of claim 1, the system comprising:

a processor for executing the computer-executed instructions;

a display device coupled to said processor;

a user input device coupled to said processor, said user input device transferring user commands and data to said processor; and

a storage device coupled to said processor.

11. A method for scaling a map based on associated overlay data, the method comprising the steps of:

(a) intersecting vector representations of a plurality of geographical or political entities with one or more raster images to create a plurality of logical data segments, each logical data segment corresponding to the vector representation of a corresponding geographical or political;

(b) linearly registering overlay data to each logical segment;

(c) calculating a corresponding data density for each logical segment;

(d) scaling each logical segment based on the corresponding data density for the logical segment;

(e) repositioning at least one logical segment in relation to another logical segment;

(f) determining whether any logical segment overlaps any other logical segment; and

(g) providing a map containing the scaled logical segments.

12. The method of claim 11, wherein steps (c) through (f) are repeated until no logical segments overlaps any other logical segment.

13. The method of claim 11, wherein each logical segment comprises pixels and has a corresponding segment pixel area and the step of scaling each logical segment further comprises scaling the corresponding segment pixel area.

14. The method of claim 13, wherein the step of calculating a corresponding data density further comprises calculating a corresponding segment data density from the ratio of an overlay pixel area factor to a segment pixel area factor.

15. The method of claim 14, wherein the step of scaling each logical segment comprises:

specifying a density ratio factor;

comparing the corresponding segment data density for each logical segment to the density ratio factor;

increasing the segment pixel area for the logical segment if the segment data density for the logical segment is greater than the density factor; and

decreasing the segment pixel area for the logical segment if the segment data density for the logical segment is less than the density factor.

16. The method of claim 15, wherein a maximum pixel area and a minimum pixel area is specified and the segment pixel area is maintained between the maximum pixel area and the minimum pixel area.

17. The method of claim 11 wherein the logical segments have a hierarchical organization with each logical segment having a parent segment and the parent segment being the same for each logical segment, the parent segment having a center of mass and the step of repositioning at least one logical segment comprises at least one of the following steps:

moving the at least one logical segment incrementally toward or away from the center of mass;

moving the at least one logical segment angularly around the center of mass; and

moving the at least one logical segment incrementally toward or away from the center of mass and moving the at least one logical segment angularly around the center of mass.

18. The method of claim 17 wherein a calculated overlap ratio is calculated for each logical segment, the calculated overlap ratio being a ratio of an overlap between the logical segment and the parent segment, and the at least one logical segment is moved towards the center of mass if the overlap ratio is less than a specified intersection ratio and the at least one logical segment is moved away from the center of mass if the overlap ratio is greater than the specified intersection ratio.

19. The method of claim 17, wherein a maximum distance and maximum angle is specified and the at least one segment is moved a distance less than the specified maximum distance and the at least one segment is moved angularly at an angle less than the maximum angle.

20. A computer-readable medium having computer-executable instructions for performing the method according to claim 11.

21. A computer system using computer-executed instructions for performing the method of claim 11, the system comprising:

a processor for executing the computer-executed instructions;

a display device coupled to said processor;

a user input device coupled to said processor, said user input device transferring user commands and data to said processor; and

a storage device coupled to said processor.