Capturing and Processing of Images Including Occlusions Captured by Arrays of Luma and Chroma Cameras

• US 20140347509A1
• Filed: 08/13/2014
• Published: 11/27/2014
• Est. Priority Date: 05/20/2008
• Status: Active Grant

• Current Assignee: FotoNation Limited (Adeia Inc.)
• Original Assignee: Pelican Imaging Corporation
• Inventors: Venkataraman, Kartik, Jabbi, Amandeep S., Mullis, Robert H., Duparre, Jacques, Hu, Shane Ching-Feng
• Granted Patent: US 9,124,815 B2
• Time in Patent Office: Days
• US Class Current: 348/218.1
• CPC Class Codes: G02B 13/0015 characterised by the lens design
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G02B 3/0062 Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between
• CPC Class Codes: G02B 5/20 Filters polarising elements G02B5/30
• CPC Class Codes: G02B 5/201 in the form of arrays
• CPC Class Codes: G06T 11/60 Editing figures and text; Combining figures or text
• CPC Class Codes: G06T 19/20 Editing of 3D images, e.g. changing shapes or colours, aligning objects or positioning parts
• CPC Class Codes: G06T 2200/04 involving 3D image data
• CPC Class Codes: G06T 2207/10028 Range image; Depth image; 3D point clouds
• CPC Class Codes: G06T 2207/10052 Images from lightfield camera
• CPC Class Codes: G06T 2207/20221 Image fusion; Image merging
• CPC Class Codes: G06T 7/50 Depth or shape recovery
• CPC Class Codes: G06T 7/557 from light fields, e.g. from plenoptic cameras
• CPC Class Codes: H04N 13/128 Adjusting depth or disparity
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/257 Colour aspects
• CPC Class Codes: H04N 2013/0081 Depth or disparity estimation from stereoscopic image signals
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/13 with multiple sensors
• CPC Class Codes: H04N 23/16 Optical arrangements associated therewith, e.g. for beam-splitting or for colour correction
• CPC Class Codes: H04N 23/45 : for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/54 : Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/55 : Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/60 : Control of cameras or camera modules
• CPC Class Codes: H04N 23/69 : Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: H04N 23/698 : for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 23/88 : for colour balance, e.g. white-balance circuits or colour temperature control
• CPC Class Codes: H04N 23/90 : Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums
• CPC Class Codes: H04N 23/951 : by using two or more images to influence resolution, frame rate or aspect ratio
• CPC Class Codes: H04N 25/131 : including elements passing infrared wavelengths
• CPC Class Codes: H04N 25/133 : including elements passing panchromatic light, e.g. filters passing white light
• CPC Class Codes: H04N 25/135 : based on four or more different wavelength filter elements
• CPC Class Codes: H04N 25/41 : Extracting pixel data from a plurality of image sensors simultaneously picking up an image, e.g. for increasing the field of view by combining the outputs of a plurality of sensors
• CPC Class Codes: H04N 25/48 : Increasing resolution by shifting the sensor relative to the scene
• CPC Class Codes: H04N 25/581 : acquired simultaneously
• CPC Class Codes: H04N 25/60 : Noise processing, e.g. detecting, correcting, reducing or removing noise
• CPC Class Codes: H04N 25/67 : applied to fixed-pattern noise, e.g. non-uniformity of response
• CPC Class Codes: H04N 25/705 : Pixels for depth measurement, e.g. RGBZ
• CPC Class Codes: H04N 25/79 : Arrangements of circuitry being divided between different or multiple substrates, chips or circuit boards, e.g. stacked image sensors
• CPC Class Codes: H04N 5/262 : Studio circuits, e.g. for mixing, switching-over, change of character of image, other special effects ; Cameras specially adapted for the electronic generation of special effects
• CPC Class Codes: H04N 5/265 : Mixing

Abstract

Systems and methods for implementing array cameras configured to perform super-resolution processing to generate higher resolution super-resolved images using a plurality of captured images and lens stack arrays that can be utilized in array cameras are disclosed. An imaging device in accordance with one embodiment of the invention includes at least one imager array, and each imager in the array comprises a plurality of light sensing elements and a lens stack including at least one lens surface, where the lens stack is configured to form an image on the light sensing elements, control circuitry configured to capture images formed on the light sensing elements of each of the imagers, and a super-resolution processing module configured to generate at least one higher resolution super-resolved image using a plurality of the captured images.

Claims

1. A camera array, comprising:

a plurality of imagers, where each imager comprises;

optics comprising at least one lens element and at least one aperture that form an optical channel; and

an sensor comprising a two dimensional array of pixels and control circuitry for controlling imaging parameters;

a controller configured to control operation parameters of the plurality of imagers; and

an image processing pipeline module configured to process multiple images captured by the plurality of imagers;

wherein the plurality of imagers are configured to capture different images of the same scene and includes at least one imager dedicated to sampling luma and at least one imager dedicated to sampling chroma;

wherein the images captured by the plurality of imagers include different occlusions sets, where the occlusion set of a given imager is the portion of a scene visible to a baseline imager in the plurality of imagers that is occluded from the view of the given imager;

wherein the plurality of imagers includes a first imager that captures pixels around an edge of a foreground object that is visible to the baseline imager and is in the occlusion set of a second of the plurality of imagers that has the same imaging characteristics as the first imager; and

wherein the image processing pipeline module is configured to;

measure parallax using images captured by the plurality of imagers to produce a depth map; and

fuse at least the images captured by the baseline imager, and the first and second of the plurality of imagers having the same imaging characteristics to produce an image; and

wherein the image processing pipeline module is configured to reconstruct color information around the edge of the foreground object that is visible to the baseline imager and in the occlusion set of the second of the plurality of imagers using the pixels captured by the first imager.

2. The camera array of claim 1, wherein the baseline imager is selected from the group consisting of:

a monochromatic imager including a Green spectral filter;

a near-IR imager; and

a polychromatic imager.

3. The camera array of claim 1, wherein the first and second imagers are dedicated to sampling chroma and are arranged symmetrically around the baseline camera to address occlusion due to parallax.

4. The camera array of claim 1, wherein the camera array comprises a monolithic array assembly comprising:

a lens stack array comprising an array of optical channels that form the optics of each imager; and

a single semiconductor substrate on which all of the pixels and control circuitry for each imager are formed.

5. The camera array of claim 1, wherein the plurality of imagers are formed on separate semiconductor substrates.

6. The camera array of claim 1, wherein the plurality of imagers are mounted to a motherboard.

7. The camera array of claim 1, wherein the plurality of imagers each have the same resolution.

8. The camera array of claim 1, wherein the plurality of imagers comprises imagers having different resolutions.

10. The camera array of claim 1, wherein an imager dedicated to sampling chroma includes at least one spectral filter configured to pass a specific spectral band of light selected from the group consisting of Red and Blue spectral filters.

11. The camera array of claim 1, wherein an imager dedicated to sampling chroma includes a Bayer filter.

12. The camera array of claim 11, wherein the Bayer filter comprises Red, Green, and Blue spectral filters

13. The camera array of claim 11, wherein the Bayer filter comprises Cyan, Magenta, and Yellow spectral filters

14. The camera array of claim 11, wherein the spectral filters in the Bayer filter provide full spectral data for the visible light spectrum.

15. The camera array of claim 1, wherein the control circuitry of the at least one imager dedicated to luma sampling and the at least one imager dedicated to chroma sampling configure the imagers to operate with at least one difference in operating parameters.

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 1, wherein the plurality of imagers includes imagers having apertures of different sizes.

18. The camera array of claim 17, wherein an imager dedicated to luma sampling has a larger aperture than an imager dedicated to sampling chroma.

19. The camera array of claim 17, wherein an imager dedicated to luma sampling has a smaller aperture than an imager dedicated to sampling chroma.

20. The camera array of claim 1, wherein the plurality of imagers includes imagers having different exposure times.

21. The camera array of claim 20, wherein an imager dedicated to luma sampling has a longer exposure time than an imager dedicated to sampling chroma.

22. The camera array of claim 20, wherein an imager dedicated to luma sampling has a shorter exposure time than an imager dedicated to sampling chroma.

23. The camera array of claim 1, wherein the fields of view of the plurality of imagers at least partially overlap.

24. The camera array of claim 1, wherein the camera array comprises an array of between 2×

2 and 6×

6 imagers.

25. The camera array of claim 1, wherein the camera array comprises a linear array of imagers.

26. The camera array of claim 25, wherein the linear array of imagers comprises at least one selected from the group consisting of:

a 1×

4 array of imagers; and

a 1×

10 array of imagers.

27. The camera array of claim 1, wherein the image processing pipeline module comprises a parallax confirmation and measurement module configured to measure parallax using images captured by the plurality of imagers by:

detecting parallax-induced changes that are consistent across the captured images taking into account the position of the imagers that captured the images; and

ignoring pixels in the captured images that are in the occlusion set of a baseline imager.

28. 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 the produced image based upon the depth map.

9. The camera array of claim 9, wherein an imager dedicated to sampling luma has greater resolution than an imager dedicated to sampling chroma.

29. A camera array assembly, comprising:

a monolithic integrated module forming a plurality of imagers, where each imager comprises;

a lens stack array comprising an array of optical channels that form the optics of each imager, where each optical channel comprises at least one lens element and at least one aperture forming a lens stack; and

a single semiconductor substrate on which all of the pixels and control circuitry for each imager are formed;

a controller configured to control operation parameters of the plurality of imagers; and

an image processing pipeline module configured to process multiple images captured by the linear array of imagers;

wherein the imagers in the linear array of imagers are configured to capture different images of the same scene;

wherein the images captured by the linear array of imagers include different occlusions sets, where the occlusion set of a given imager is the portion of a scene visible to a baseline imager that is occluded from the view of the given imager;

wherein the linear array of imagers includes a first imager that captures pixels around an edge of a foreground object that is visible to the baseline imager and is in the occlusion set of a second imager that has the same imaging characteristics as the first imager;

wherein the baseline imager is dedicated to sampling luma;

wherein the first and second imagers are dedicated to sampling chroma and are arranged symmetrically around the baseline imager; and

wherein the image processing pipeline module is configured to;

measure parallax using images captured by the plurality of imagers to produce a depth map; and

fuse at least the images captured by the baseline imager, and the first and second imagers having the same imaging characteristics to produce an image; and

wherein the image processing pipeline module is configured to reconstruct color information around the edge of the foreground object that is visible to the baseline imager and in the occlusion set of the second imager using the pixels captured by the first imager; and

wherein the image processing pipeline module is configured to select at least one distance as an “

in best focus”

distance and blur the produced image based upon the depth map.

30. A camera array, comprising:

a plurality of imagers formed on separate semiconductor substrates and mounted to a motherboard, where each imager comprises;

optics comprising at least one lens element and at least one aperture that form an optical channel; and

a sensor comprising a two dimensional array of pixels and control circuitry for controlling imaging parameters;

a controller configured to control operation parameters of the linear array of imagers; and

an image processing pipeline module configured to process multiple images captured by the linear array of imagers;

wherein the imagers in the linear array of imagers are configured to capture different images of the same scene;

wherein the images captured by the linear array of imagers include different occlusions sets, where the occlusion set of a given imager is the portion of a scene visible to a baseline imager that is occluded from the view of the given imager;

wherein the linear array of imagers includes a first imager that captures pixels around an edge of a foreground object that is visible to the baseline imager and is in the occlusion set of a second imager that has the same imaging characteristics as the first imager;

wherein the baseline imager is dedicated to sampling luma;

wherein the first and second imagers are dedicated to sampling chroma and are arranged symmetrically around the baseline imager; and

wherein the image processing pipeline module is configured to;

measure parallax using images captured by the plurality of imagers to produce a depth map; and

fuse at least the images captured by the baseline imager, and the first and second imagers having the same imaging characteristics to produce an image; and

wherein the image processing pipeline module is configured to reconstruct color information around the edge of the foreground object that is visible to the baseline imager and in the occlusion set of the second imager using the pixels captured by the first imager; and

wherein the image processing pipeline module is configured to select at least one distance as an “

in best focus”

distance and blur the produced image based upon the depth map.