Mosaic oblique images and methods of making and using same
A computer system running image processing software receives an identification of a desired geographical area to be imaged and collected into an oblique-mosaic image; creates a mathematical model of a virtual camera looking down at an oblique angle, the mathematical model having an oblique-mosaic pixel map of the desired area encompassing multiple source images; assigns surface locations to pixels included in the oblique-mosaic pixel map; creates a ground elevation model of the ground and vertical structures within the oblique-mosaic pixel map using overlapping source images of the desired geographical area, wherein the source oblique images were captured at an oblique angle and compass direction similar to that of the virtual camera; and reprojects, with the mathematical model, source oblique image pixels of the overlapping source images for pixels included in the oblique-mosaic pixel map using the ground elevation model to thereby create an oblique-mosaic image of the desired area.
1. A system comprising:
a computer system running image processing software that when executed by the computer system causes the computer system to:
receive an identification of a desired geographical area to be imaged and collected into an oblique-mosaic image;
assign surface locations to pixels included in an oblique-mosaic pixel map of the desired geographical area encompassing multiple source images, the oblique-mosaic pixel map being part of a mathematical model of a virtual camera looking down at an oblique angle onto the desired geographical area;
create a ground elevation model of the ground and vertical structures within the oblique-mosaic pixel map using overlapping source images of the desired geographical area, wherein the source images were captured at an oblique angle and compass direction similar to the oblique angle and compass direction of the virtual camera; and
reproject, with the mathematical model, source oblique image pixels of the overlapping source images for pixels included in the oblique-mosaic pixel map using the ground elevation model to thereby create an oblique-mosaic image of the desired area.
2. The system of claim 1 , wherein the virtual camera has a perspective, and wherein the image processing software further causes the computer system to project each pixel through the perspective of the virtual camera to determine a corresponding surface location for each pixel in the oblique-mosaic pixel map.
3. The system of claim 1 , wherein multiple source oblique images represent a same surface location.
4. The system of claim 3 , wherein the image processing software further causes the computer system to compare the pixels of each source oblique image that represent the same surface location to determine which source pixel is most representative of the surface location, the more representative pixel to be included in the oblique-mosaic image.
5. The system of claim 1 , wherein each pixel included in the oblique-mosaic pixel map is reprojected to match a size and shape of a represented surface location as taken from the elevation, compass direction, and oblique angle of the virtual camera.
6. The system of claim 1 , wherein the image processing software further causes the computer system to remove effects of elevation from the source oblique images prior to reprojection and then to add the effects of elevation to the oblique-mosaic image after reprojection.
7. The system of claim 1 , wherein lean of vertical structures within the oblique-mosaic image is minimized.
8. The system of claim 7 , wherein minimizing lean of vertical structures is defined further as matching vertical structures in multiple source oblique images and shifting pixels apparent location in at least one of the source oblique images by a relative height above a ground model.
9. The system of claim 1 , wherein metadata is stored with the oblique-mosaic image.
10. A system comprising:
a computer system running image processing software that when executed by the computer system causes the computer system to:
receive an identification of a desired geographical area to be imaged and collected into an oblique-mosaic image;
determine geographic coordinates for pixels included in an oblique-mosaic pixel map of the desired geographical area encompassing multiple source images, the oblique-mosaic pixel map being part of a mathematical model of a virtual camera looking down at an oblique angle onto the desired geographical area;
create a ground elevation model of the ground and vertical structures within the oblique-mosaic pixel map using overlapping source images of the desired geographical area, wherein the source images were captured at an oblique angle and compass direction similar to the oblique angle and compass direction of the virtual camera; and
reproject, with the mathematical model, using the ground elevation model to define a ground surface and surfaces of vertical structures within the desired geographical area, at least one source oblique image pixel of the overlapping source images from a vantage point of the virtual camera for pixels included in the oblique-mosaic pixel map to thereby create a geo-referenced oblique-mosaic image of the desired geographical area.
11. The system of claim 10 , wherein the virtual camera has a perspective, and wherein the image processing software further causes the computer system to project each pixel through the perspective of the virtual camera to determine a corresponding surface location for each pixel in the oblique-mosaic pixel map.
12. The system of claim 10 , wherein multiple source oblique images represent a same surface location.
13. The system of claim 12 , wherein the image processing software further causes the computer system to compare the pixels of each source oblique image that represent a same surface location to determine which source pixel is most representative of the surface location, the more representative pixel to be included in the oblique-mosaic image.
14. The system of claim 10 , wherein the pixel is reprojected to match a size and shape of the represented surface location as taken from the elevation, compass direction, and oblique angle of the virtual camera.
15. The system of claim 10 , wherein the image processing software further causes the computer system to remove effects of elevation from the source oblique images prior to reprojection and then to add the effects of elevation to the oblique-mosaic image after reprojection.
16. The system of claim 10 , wherein lean of vertical structures within the oblique mosaic image is minimized.
17. The system of claim 16 , wherein minimizing lean of vertical structures is defined further as matching vertical structures in multiple source oblique images and shifting pixels apparent location in at least one of the source oblique images by a relative height above a ground model.
18. The system of claim 10 , wherein metadata is stored with the oblique-mosaic image.