Methods and systems for reducing image artifacts

1. A method for imaging a scene, the method comprising:

modulating light from the scene using a diffractive optic to produce an interference pattern;

sampling the interference pattern to acquire sampled frequency-domain image data representing the scene;

modifying the sampled frequency-domain image data responsive to an image property of the sampled frequency-domain image data to produce modified frequency-domain data; and

after modifying the sampled frequency-domain image data, transforming the modified frequency-domain image data into a pixel-domain image of the scene.

2. The method of claim 1 , wherein the image property represents an aspect of the scene.

3. The method of claim 2 , wherein the image property comprises a saturation region.

4. The method of claim 3 , wherein the saturation region corresponds to a point source in the scene.

5. The method of claim 1 , wherein the image property represents a low-confidence area.

6. A method for imaging a scene, the method comprising:

modulating light from the scene using a diffractive optic to produce an interference pattern;

sampling the interference pattern to acquire sampled frequency-domain image data representing the scene; and

modifying the sampled frequency-domain image data responsive to an image property of the sampled frequency-domain image data;

wherein the image property represents a low-confidence area; and

wherein modifying the sampled frequency-domain image data responsive to the image property comprises in-filling the low-confidence area to produce the modified frequency-domain image data.

7. The method of claim 6 , wherein the sampled frequency-domain image data comprises intensity values, the method further comprising assigning confidence values to the intensity values.

8. The method of claim 7 , wherein the in-filling comprises:

weighting the intensity values within and around the low-confidence area in proportion to their confidence values; and

combining the weighted intensity values within the low-confidence area with the weighted intensity values around the low-confidence area.

9. The method of claim 6 , wherein the diffractive optic exhibits a point-spread function, and wherein in-filling the low-confidence area comprises applying a correction pattern that is a function of the point-spread function to the sampled frequency-domain image data.

10. The method of claim 9 , wherein the diffractive optic exhibits a rotationally symmetric and circularly asymmetric point-spread function.

11. The method of claim 9 , wherein the low-confidence area represents a point response with a central-cross-sectional intensity profile that is a strong function of cross-sectional angle.

12. The method of claim 11 , wherein the point response includes features that radiate away from a center of the response in a plane of the interference pattern.

13. The method of claim 12 , wherein the features are curved.

14. The method of claim 6 , wherein locating the low-confidence area comprises deconvolving the sampled frequency-domain image data, applying a threshold to a result of a deconvolution yielding a suprathreshold deconvolution region, and grouping the suprathreshold deconvolution region into a suprathreshold scene object.

15. The method of claim 14 , wherein locating the low-confidence area further comprises determining whether the suprathreshold scene object represents a circular image artifact.

16. A method for imaging a scene, the method comprising:

modulating light from the scene using a diffractive optic to produce an interference pattern;

sampling the interference pattern to acquire sampled frequency-domain image data representing the scene;

modifying the sampled frequency-domain image data responsive to an image property of the sampled frequency-domain image data; and

identifying a saturation region in the sampled frequency-domain image data and extrapolating intensity values within the saturation region.

17. The method of claim 16 , wherein the identifying the saturation region in the sampled frequency-domain image data and the extrapolating intensity values within the saturation region are based on intensity values outside the saturation region.

18. An imaging system comprising:

a diffractive optic to produce an interference pattern representing an imaged scene in a spatial-frequency domain;

an array of photosensitive elements to sample the interference pattern as sampled frequency-domain image data representing the scene; and

a processor to modify the sampled frequency-domain image data responsive to an image property of the sampled frequency-domain image data;

wherein the diffractive optic exhibits a point-spread function, and wherein the processor applies a correction pattern that is a function of the point-spread function to the sampled frequency-domain image data; and

wherein the diffractive optic exhibits a rotationally symmetric and circularly asymmetric point-spread function.

19. A method for imaging a scene, the method comprising:

modulating light from the scene using a diffractive optic to produce an interference pattern;

sampling the interference pattern to acquire sampled frequency-domain image data representing the scene;

modifying the sampled frequency-domain image data responsive to an image property of the sampled frequency-domain image data to produce modified frequency-domain data; and

after modifying the sampled frequency-domain image data, processing the modified frequency-domain image data to form a sensing measurement.

20. The method of claim 19 , the sensing measurement to sense movement.