Flash No flash SIGGRAPH05

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Coded Exposure Raskar, Agrawal, Tumblin SIGGRAPH
2006
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Coded Exposure (Flutter Shutter) Camera
Raskar, Agrawal, Tumblin Siggraph2006
Coding in Time Shutter is opened and closed
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Coded Exposure
Traditional
Deblurred Image
Deblurred Image
Image of Static Object
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Coded Exposure
Coded Aperture
Temporal 1-D broadband code Motion Deblurring
Spatial 2-D broadband mask Focus Deblurring
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Captured Blurred Photo
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Full Resolution Digital Refocusing
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Mask?
Sensor
4D Light Field from 2D Photo Heterodyne Light
Field Camera
Full Resolution Digital Refocusing Coded
Aperture Camera
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Lenslet-based Light Field camera
Wang Adelson, 1992, Ng et al. 2005
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Optical Heterodyning
Receiver Demodulation
High Freq Carrier 100.1 MHz
Incoming Signal
ReferenceCarrier
99 MHz
Incident Modulated Signal
Photographic Signal(Light Field)
Carrier
ReferenceCarrier
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Captured 2D Photo
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Computing 4D Light Field
2D Sensor Photo, 18001800
2D Fourier Transform, 18001800
2D FFT
9981 spectral copies
Rearrange 2D tiles into 4D planes
4D IFFT
20020099
4D Light Field
20020099
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Two-Plane Parameterization of Light Field
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Captured 2D Photo
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Computing 4D Light Field
2D Sensor Photo, 18001800
2D Fourier Transform
2D FFT
9981 spectral copies
Rearrange 2D tiles into 4D planes
4D IFFT
20020099
4D Light Field
20020099
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Differences with Plenoptic Camera
Sensor
Microlens array
Plenoptic Camera
Heterodyne Camera

• Samples individual rays
• High alignment precision
• Wasted pixels
• No Light Loss

• Samples coded combination of rays
• More flexible
• No wastage
• High resolution image for parts of scene in focus
• Light Loss due to attenuating mask

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Coding and Modulation in Camera Using Masks
Coded Aperture for Full Resolution Digital
Refocusing
Heterodyne Light Field Camera
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(No Transcript)
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Digital Refocusing of Transparent Layers
4D Light Field
Refocused Photo 200200
Captured 2D Photo, 18001800