Camera-assisted arbitrary surface characterization and correction

1. A method comprising:

projecting, by a projector, a sparse structured light pattern on a projection screen surface as displayed structure light elements;

receiving, by a camera, an image of the displayed structure light elements;

determining, by at least one processor, based on the sparse structured light pattern and based on the image of the displayed structure light elements, a three-dimensional point cloud characterizing the projection screen surface;

determining, by the at least one processor, an indication of an observer position relative to the projection screen surface;

generating, by the at least one processor, a flattened characterization of the projection screen surface with respect to the observer position, the flattened characterization including two-dimensional points associated with a positions on the projection screen surface;

respacing, by the at least one processor, two-dimensional points of the flattened characterization in accordance with a spacing grid;

determining, by the at least one processor, a depth for the respaced two-dimensional points in response to the three-dimensional point cloud characterizing the projection screen surface; and

determining, by the at least one processor, compensated control points for generating an inverse image in response to the respaced two-dimensional points and the depth determined for the two-dimensional points.

2. The method of claim 1 , wherein the three-dimensional point cloud characterizing the projection screen surface includes a point cloud for storing indications of various points of a three-dimensional topography of the projection screen surface, and wherein the indications of various points of the three-dimensional topography of the projection screen surface are ordered in accordance with a grid of control points arranged as input to a warping engine of the projector.

3. The method of claim 1 , further comprising triangulating displayed elements on the projection screen surface iteratively displayed in a geometric progression.

4. The method of claim 1 , further comprising triangulating displayed elements on the projection screen surface.

5. The method of claim 4 , wherein the triangulating is determined from a first image capture location and a projector location.

6. The method of claim 4 , wherein the triangulating is determined from a first image capture location and a second image capture location.

7. The method of claim 1 , wherein the indication of the observer position is determined in response to a location of an observer.

8. The method of claim 1 , wherein the indication of the observer position is determined in response to an estimation of in response to an analysis of the three-dimensional point cloud characterizing the projection screen surface.

9. The method of claim 1 , wherein the three-dimensional point cloud characterizing the projection screen surface is rotated towards the observer position to produce a rotated characterization of the projection screen surface and wherein the flattened characterization of the projection screen surface is generated in response to the rotated characterization of the projection screen surface.

10. The method of claim 1 , wherein the depth for the respaced two-dimensional points is determined in response to a local homography transformation.

11. The method of claim 1 , wherein the depth for the respaced two-dimensional points is determined in response to localized plane fitting.

12. The method of claim 1 , wherein spacing of pixels of the inverse image is for compensating for non-planar or keystoned portions of the projection screen surface.

13. The method of claim 1 , wherein the inverse image when projected on the projection screen surface compensates for non-planar portions of the projection screen surface when viewed from the observer position.

14. A method comprising:

projecting, by a projector, a sparse structured light pattern on a projection screen surface as displayed structure light elements;

receiving, by a camera, an image of the displayed structure light elements;

determining, by at least one processor, based on the sparse structured light pattern and based on the image of the displayed structure light elements, a three-dimensional point cloud characterizing the projection screen surface;

determining, by the at least one processor, an indication of an observer position relative to the projection screen surface;

respacing, by the at least one processor, points of the three-dimensional point cloud characterizing the projection screen surface, wherein the points are respaced in accordance with a spacing grid;

determining, by the at least one processor, compensated depths for the respaced points in response to the three-dimensional point cloud characterizing the projection screen surface; and

projecting, by the at least one processor, an inverse image in response to the respaced points and the compensated depth.

15. The method of claim 14 , wherein the three-dimensional point cloud characterizing the projection screen surface includes a point cloud for storing indications of various points of a three-dimensional topography of the projection screen surface, and wherein the indications of various points of the three-dimensional topography of the projection screen surface are ordered in accordance with a grid of control points arranged as input to a warping engine of the projector.

16. The method of claim 15 , wherein the three-dimensional point cloud characterizing the projection screen surface includes determining distances of displayed elements on the projection screen surface displayed iteratively in a geometric progression.

17. The method of claim 16 , wherein the distances of displayed elements are determined in response to a first image capture location and a projector location.

18. The method of claim 1 , wherein the sparse structured light pattern is a pattern of circles, a pattern of rectangles, a pattern of Gaussians, a sinusoidal sequence, or a De Bruijn sequence.