Systems and methods for measuring depth using images captured by monolithic camera arrays including at least one bayer camera
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 monolithic integrated module forming a plurality of cameras, where each camera comprises:
a lens element array forming the optics of each of the plurality of cameras, where the optics of each camera comprises at least one lens element and at least one aperture; and
a single semiconductor substrate on which all of the pixels and control circuitry for each camera are formed; and
at least one spectral filter located within each camera, where each spectral filter is configured to pass a specific spectral band of light;
a controller configured to control operation parameters of the camera array; and
an image processing pipeline module comprising a parallax confirmation and measurement module;
wherein the plurality of cameras forms at least a 2×2 array of cameras that includes multiple redundant pairs of cameras;
wherein at least one camera includes a Bayer filter;
wherein images captured by the plurality of cameras include different occlusions sets, where the occlusion set of a first camera is the portion of a scene visible to a second camera in the plurality of cameras that is occluded from the view of the first camera;
wherein the image processing pipeline module comprises a parallax confirmation and measurement module configured to measure parallax using images captured by the plurality of cameras by:
detecting parallax-induced changes that are consistent across the plurality of cameras taking into account the position of the cameras within the at least 2×2 array of cameras; and
ignoring pixels in the images captured by the plurality of cameras that are in an exposed occlusion set; and
wherein the parallax confirmation and measurement module is further configured to estimate distance to an object in images captured by the plurality of cameras using measured parallax.
2. The camera array of claim 1 , wherein each camera includes a filter selected from the group consisting of a Bayer filter, one or more Blue filters, one or more Green filters, one or more Red filters, one or more shifted spectral filters, one or more near-IR filters, and one or more hyper-spectral filters.
3. The camera array of claim 1 , wherein the Bayer filter comprises Red, Green, and Blue color filters.
4. The camera array of claim 1 , wherein the Bayer filter comprises Cyan, Magenta, and Yellow color filters.
5. The camera array of claim 1 , wherein the spectral filters in the Bayer filter provide full spectral data for the visible light spectrum.
6. The camera array of claim 1 , wherein detecting parallax-induced changes that are consistent across the plurality of cameras taking into account the position of the cameras within the at least 2×2 array of cameras comprises keeping track of various pair-wise parallax measurements and calculating an actual parallax difference using a least squares fit to the sample data.
7. The camera array of claim 1 , wherein the parallax confirmation and measurement module is further configured to generate a depth map using measured parallax.
8. 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.
9. The camera array of claim 8 , wherein the parallax information includes a depth map.
10. The camera array of claim 9 , wherein the super-resolution processing module is configured to select at least one distance as a focal plane and to apply blurring to pixels in at least one higher resolution super-resolved image with depths in the depth map that are not proximate a focal plane.
11. The camera array of claim 1 , wherein the camera array comprises a 2×2 array of cameras.
12. The camera array of claim 1 , wherein the camera array comprises a 3×3 array of cameras.
13. The camera array of claim 1 , wherein the camera array comprises a 4×4 array of cameras.
14. The camera array of claim 1 , wherein the camera array comprises a 5×5 array of cameras.
15. The camera array of claim 1 , wherein the plurality of cameras comprises at least one camera having a first set of imaging characteristics and at least one camera having a second set of imaging characteristics.
16. The camera array of claim 15 , 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.
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 15 , wherein the plurality of cameras comprises a distribution of cameras selected from the group consisting of: a symmetric distribution of cameras of different types; and an irregular distribution of cameras of different types.
19. The camera array of claim 1 , wherein each of the plurality of cameras have the same imaging characteristics.
20. A camera array, comprising:
a monolithic integrated module forming a 2×2 array of cameras, comprising:
a lens element array comprising a 2×2 array of camera optics, where the optics of each camera comprises at least one lens element and at least one aperture; and
a single semiconductor substrate on which all of the pixels and control circuitry for each camera are formed; and
at least one spectral filter located within each camera, where each spectral filter is configured to pass a specific spectral band of light;
a controller configured to control operation parameters of the camera array; and
an image processing pipeline module comprising a parallax confirmation and measurement module;
wherein each of the plurality of cameras have the same imaging characteristics and include a Bayer filter;
wherein images captured by the plurality of cameras include different occlusions sets, where the occlusion set of a first camera is the portion of a scene visible to a second camera in the plurality of cameras that is occluded from the view of the first camera; and
wherein the image processing pipeline module comprises a parallax confirmation and measurement module configured to measure parallax using images captured by the plurality of cameras by:
detecting parallax-induced changes that are consistent across the plurality of cameras taking into account the position of the cameras within the 2×2 array of cameras; and
ignoring pixels in the images captured by the plurality of cameras that are in an exposed occlusion set; and
wherein the parallax confirmation and measurement module is further configured to generate a depth map using measured parallax.