Capturing and processing of near-IR images including occlusions using camera arrays incorporating near-IR light sources
View Patent ↗A camera array, an imaging device and/or a method for capturing image that employ a plurality of imagers fabricated on a substrate is provided. Each imager includes a plurality of pixels. The plurality of imagers include a first imager having a first imaging characteristics and a second imager having a second imaging characteristics. The images generated by the plurality of imagers are processed to obtain an enhanced image compared to images captured by the imagers. Each imager may be associated with an optical element fabricated using a wafer level optics (WLO) technology.
1. A camera array, comprising:
a plurality of cameras configured to capture images of a scene, where each camera comprises:
optics comprising at least one lens element and at least one aperture;
a sensor comprising a two dimensional array of pixels and control circuitry for controlling imaging parameters; and
a near-IR light source configured to illuminate the scene during image capture;
a controller configured to control operation parameters of the plurality of cameras; and
an image processing pipeline module;
wherein the plurality of cameras includes multiple cameras configured to capture near-IR images;
wherein the plurality of cameras includes at least one camera configured to capture a visible light image;
wherein the image processing pipeline module is configured to generate a depth map using near-IR images captured by the multiple cameras configured to capture near-IR images by:
detecting parallax-induced changes that are consistent across the captured images taking into account the position of the cameras that captured the images; and
ignoring pixels in the captured images that are in an exposed occlusion set.
2. The camera array of claim 1 , wherein the image processing pipeline is configured to fuse a near-IR image with an image captured by a camera configured to capture a visible light image.
3. The camera array of claim 2 , wherein the image processing pipeline module is configured to interpolate the near-IR image to grid points that correspond to each grid point on the visible light image.
4. The camera array of claim 1 , wherein the plurality of cameras further comprises a camera configured to capture a visible light image using a wide angle lens.
5. The camera array of claim 4 , wherein the wherein the multiple cameras configured to capture near-IR images are distributed on either side of the camera configured to capture a visible light image using a wide angle lens.
6. The camera array of claim 1 , wherein the multiple cameras configured to capture near-IR images are arranged symmetrically within the camera array to address occlusion due to parallax.
7. The camera array of claim 1 , wherein the multiple cameras configured to capture near-IR images are arranged symmetrically with respect to a central camera so that at least two cameras configured to capture near-IR images capture pixels around the edge of a foreground object.
8. The camera array of claim 7 , wherein the central camera is dedicated to sampling luma.
9. The camera array of claim 8 , wherein the central camera is selected from the group consisting of: a monochromatic camera including a Green spectral filter; a camera including a near-IR spectral filter; and a polychromatic camera.
10. The camera array of claim 8 , wherein at least one of the cameras is configured to sample chroma.
11. The camera array of claim 10 , wherein at least one camera configured to sample chroma includes spectral filters selected from the groups consisting of:
Red, Green, and Blue spectral filters; and
Cyan, Magenta, and Yellow spectral filters.
12. The camera array of claim 1 , wherein the camera array comprises a monolithic camera array assembly comprising:
a lens element array forming the optics of each camera; and
a single semiconductor substrate on which all of the pixels and control circuitry for each camera are formed.
13. The camera array of claim 1 , wherein the plurality of cameras are formed on separate semiconductor substrates.
14. The camera array of claim 1 , wherein the plurality of cameras each have the same resolution.
15. The camera array of claim 1 , wherein the plurality of cameras comprises cameras having different resolutions.
16. The camera array of claim 1 , wherein the control circuitry of the multiple cameras that include near-IR filters configure the cameras to operate with at least one difference in operating parameters.
17. The camera array of claim 16 , wherein the at least one difference in operating parameters includes at least one imaging parameter selected from the group consisting of exposure time, gain, and black level offset.
18. The camera array of claim 1 , wherein the plurality of cameras includes cameras having apertures of different sizes.
19. The camera array of claim 1 , wherein the plurality of cameras includes cameras having different exposure times.
20. The camera array of claim 1 , wherein the camera array comprises an array of between 2×2 and 6×6 cameras.
21. The camera array of claim 1 , wherein the camera array comprises a linear array of cameras.
22. The camera array of claim 21 , wherein the linear array of cameras comprises at least one selected from the group consisting of: a 1×4 array of cameras; and a 1×10 array of cameras.
23. The camera array of claim 1 , wherein the image processing pipeline module is configured to select at least one distance as an “in best focus” distance and blur an image produced by the camera array based upon the depth map.
24. The camera array of claim 1 , wherein the image processing pipeline module further comprises a super-resolution processing module configured to generate at least one higher resolution super-resolved image using images captured by the plurality of cameras and parallax measurements from the parallax confirmation and measurement module to compensate for parallax in the captured images.
25. A camera array, comprising:
a linear array of cameras configured to capture images of a scene, where each camera in the linear array comprises:
optics comprising at least one lens element and at least one aperture; and
a sensor comprising a two dimensional array of pixels and control circuitry for controlling imaging parameters;
a near-IR light source configured to illuminate the scene during image capture;
a controller configured to control operation parameters of the linear array of cameras; and
an image processing pipeline module;
wherein the linear array of cameras includes cameras that have different resolutions and fields of view;
wherein the linear array of cameras includes a central camera dedicated to sampling luma;
wherein the camera dedicated to sampling luma is configured to capture a visible light image using a wide angle lens;
wherein the linear array of cameras includes multiple cameras configured to capture near-IR images distributed on either side of the central camera; and
wherein the image processing pipeline module is configured to generate a depth map for a visible light image produced by the camera array using images captured by the linear array of cameras.