Distortion correcting sensors for diagonal collection of oblique imagery
A vehicle collects oblique imagery along a nominal heading using rotated camera-groups with optional distortion correcting electronic image sensors that align projected pixel columns or rows with a pre-determined direction on the ground, thereby improving collection quality, efficiency, and/or cost. In a first aspect, the camera-groups are rotated diagonal to the nominal heading. In a second aspect, the distortion correcting electronic image sensors align projected pixel columns or rows with a pre determined direction on the ground. In a third aspect, the distortion correcting electronic image sensors are rotated around the optical axis of the camera. In a fourth aspect, cameras collect images in strips and the strips from different cameras overlap, providing large-baseline, small-time difference stereopsis.
1. An method comprising:
operating a vehicle in a nominal heading;
capturing oblique imagery of a surface via one or more respective camera-groups;
wherein at least one of the respective camera-groups is oriented at a particular plan angle with respect to the nominal heading and includes at least one distortion correcting electronic image sensor;
wherein the particular plan angle is an oblique angle with respect to the nominal heading;
wherein the at least one distortion correcting electronic image sensor comprises a plurality of non-uniform pixel elements; and
wherein the at least one distortion correcting electronic image sensor is configured such that the non-uniform pixel elements, when projected onto the surface, are approximately transformed from a trapezoid to a rectangle.
2. An method comprising:
operating a vehicle in a nominal heading;
capturing oblique imagery of a surface via one or more respective camera-groups;
wherein at least one of the respective camera-groups is oriented at a particular plan angle with respect to the nominal heading and includes a plurality of distortion correcting electronic image sensors; wherein the particular plan angle is an oblique angle with respect to the nominal heading; and wherein each of the distortion correcting electronic image sensors is rotated at a respective angle in accordance with any two or more of increasing a swath width, increasing signal-to-noise ratio, and increasing uniformity of projection of pixels onto the surface.
3. An apparatus comprising:
one or more respective camera-groups each enabled to capture oblique imagery of a surface, the respective camera-groups are enabled to operate in a vehicle in accordance with a nominal heading;
at least one distortion correcting electronic image sensor included in at least one of the respective camera-groups, the at least one of the respective camera-groups are oriented at a particular plan angle with respect to the nominal heading;
wherein the particular plan angle is an oblique angle with respect to the nominal heading;
wherein the at least one distortion correcting electronic image sensor comprises a plurality of non-uniform pixel elements; and
wherein the at least one distortion correcting electronic image sensor is configured such that the non-uniform pixel elements, when projected onto the surface, are approximately transformed from a trapezoid to a rectangle.
4. An apparatus comprising:
one or more respective camera-groups each enabled to capture oblique imagery of a surface, the respective camera-groups are enabled to operate in a vehicle in accordance with a nominal heading; at least one distortion correcting electronic image sensor included in at least one of the respective camera-groups, the at least one of the respective camera-groups are oriented at a particular plan angle with respect to the nominal heading;
wherein the at least one of the respective camera-groups is oriented at a particular plan angle with respect to the nominal heading and includes a plurality of distortion correcting electronic image sensors;
wherein the particular plan angle is an oblique angle with respect to the nominal heading; and wherein each of the distortion correcting electronic image sensors is rotated at a respective angle in accordance with any two or more of increasing a swath width, increasing signal-to-noise ratio, and increasing uniformity of projection of pixels onto the surface.
5. The method of claim 1 , wherein the capturing oblique imagery is in accordance with a down angle of the at least one of the respective camera-groups, and the configuring is based at least in part on the down angle.
6. The method of claim 1 , wherein the configuring is in accordance with any one or more of increasing a swath width, increasing signal-to-noise ratio, and increasing uniformity of projection of pixels onto the surface.
7. The method of claim 1 , wherein the oblique angle is any acute angle modulo 90 degrees.
8. The method of claim 1 , wherein the oblique angle is between 15 and 75 degrees modulo 90 degrees.
9. The method of claim 1 , wherein the vehicle is a flying vehicle and the surface is the ground.
10. The method of claim 7 , wherein the oblique angle is any acute angle modulo 90 degrees.
11. The method of claim 7 , wherein the oblique angle is between 15 and 75 degrees modulo 90 degrees.
12. The method of claim 7 , wherein the vehicle is a flying vehicle and the surface is the ground.
13. The apparatus of claim 3 , wherein the capturing oblique imagery is in accordance with a down angle of the at least one of the respective camera-groups, and the configuring is based at least in part on the down angle.
14. The apparatus of claim 3 , wherein the configuring is in accordance with any one or more of increasing a swath width, increasing signal-to-noise ratio, and increasing uniformity of projection of pixels onto the surface.
15. The apparatus of claim 3 , wherein the oblique angle is any acute angle modulo 90 degrees.
16. The apparatus of claim 3 , wherein the oblique angle is between 15 and 75 degrees modulo 90 degrees.
17. The apparatus of claim 3 , wherein the vehicle is a flying vehicle and the surface is the ground.
18. The apparatus of claim 4 , wherein the oblique angle is any acute angle modulo 90 degrees.
19. The apparatus of claim 4 , wherein the oblique angle is between 15 and 75 degrees modulo 90 degrees.
20. The apparatus of claim 4 , wherein the vehicle is a flying vehicle and the surface is the ground.