3D Photography: Beyond Perspective
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Transcript of 3D Photography: Beyond Perspective
Steve SeitzDept. Computer Science & Eng.
University of Washington
3D Photography:Beyond Perspective
Perspective Projection
Humans evolved with perspective eyes• Capture light along rays that converge at a single point
Cameras also evolved with perspective optics
• Optimized for humans, not computers!
A non-perspective image
The Blue Marble, NASA satellite image composite
The Blue Marble, NASA satellite image composite
The Blue Marble, NASA satellite image composite
Cyberware Scanner
Print Gallery, by M.C. Escher, 1956
Panorama from Disney’s 1940 film Pinocchio (from Wood et al., SIGGRAPH 1997)
What’s an Image?
An image is any 2D subset of rays in space• Actually, the light energy flowing along these rays• Any 2D “slice” of the plenoptic function
perspective image general image
Non-perspective Imaging
Issues:• What other types of images are possible?• Which images are useful?• How can we capture these images?
Path Images
Path Images
Path Images
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Path Images
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Path Images
Pushbroom images• satellite
Bolles et al. [87]• EPI
Tsuji et al. [92]• omni-directional image
Peleg et al. [97]• manifold mosaic
Radamacher & Bishop [99]• MCOP
. . .
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Linear Path
input pushbroom images
Video Cube Demo• application by Michael Cohen et al., Microsoft
Circular Path
panorama(“concentric mosaic”)
circular EPI
input image
What are these images good for?• Applications to computer graphics,
computer vision?
Circular Stereo• [Ishiguro, Yamamoto, Tsuji, 92]
• [Peleg and Ben-Ezra, 99]
• [Shum, Kalai, Seitz, 99]
• [Nayar and Karmarkar, 00]
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Stereo Panorama
Disparity map result
Stereo Panorama
Dark--close, light--far
Circular Stereo
Advantages• 360 degree scene reconstruction• Uniform accuracy, optimal
Pushbroom Stereo
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Stereo Cyclographs
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Stereo Cyclograph Reconstruction
Computed from two cyclograph images• Using unmodified stereo matcher [Zitnick & Kanade]
Stereo Path Images
Do these all produce stereo pairs?• two images with horizontal parallax
Yes
Stereo Path Images
How about this path? No• Yes if the camera path is a conic
– line, circle, ellipse, parabola, hyperbola
• Must capture rays lying on doubly-ruled quadrics– [Padja 2001], [Seitz 2001]
Stereo Parabolic Panoramas
perspective image
parabolic panorama
Beyond PerspectiveCameras for humans, not machines!
• Need to rethink cameras• Image should suit the task
Future: cameras will evolve like CPU’s• First: task-specific cameras• Then: programmable cameras
– FPGA programmable camera arrays
Thanks to Jiwon Kim, Michael Cohen