Lensless Imaging with A Controllable Aperture

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Lensless Imaging with A Controllable Aperture

• Assaf Zomet and Shree K. Nayar
• Columbia University

IEEE CVPR Conference June 2006, New York, USA
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Cameras Today
Lens
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Our Lensless Camera
Volumetric
Attenuating Aperture
Image Detector
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Layered Aperture
Multilayer Aperture
Image Detector
Attenuating apertures FaridSimoncelli 97,
NayarBranzoi 03
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Implementation
Camera body
Aperture LCD
LCD Control
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Controllable Pinhole
Attenuating Layer
Pinhole
Image Detector
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Controllable Pinhole Video
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Limitations of Lensless Imaging
Optimal pinhole (Raleigh)
Brightness f-number

• Sharpness and brightness increase with FOV (image
  center).

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Limitations of Lensless Imaging
Optimal pinhole (Raleigh)
Brightness f-number

• Sharpness and brightness increase with FOV (image
  center).
• f and detector larger by factor k
• Resolution/brightness by .

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Collecting More Light Coded Apertures

• Zand, 1992

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(No Transcript)
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Split Field of View Implementation
Attenuating Layers (2nd layer physical)
Pinhole
Image Detector
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Split Field of View Results
Lens camera
Our camera
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Split Field of View Video
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Finding Faces
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Finding Faces
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Split Image Computational Camera
Correlation pattern
Image Detector
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Computations in the Optics
Our camera
Correlation Pattern
Noncoherent optical processing (Rogers 1977)
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A Camera as a Mapping
Camera Optics
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Imaging Formulation One Layer
f
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Imaging Formulation Multilayer
fj
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Varying Zoom
Conventional view
H
L
L
L
H
Desired view
L
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Varying Zoom Mapping
Scene
Desired view
MX and MX are impossible to implement with 3
layers
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Varying Zoom Imaging (simulation)

Captured
Fov 1
Fov 3
Desired
Attenuating Layers
Pinhole
Pinhole
Pinhole
Image Detector
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Varying Zoom Reconstruction
Icomputed
Icapturted
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Summary
Controllable Pinhole
Split Field of View
Computational Camera
Spatially Varying Zoom
Programmable cameras, Nayar, Branzoi Boult 2004