Concentric Mosaics

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Concentric Mosaics
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Overview of Plenoptic F(x)

• Plenoptic Function 7D
• Plenoptic Model 5D
• Lightfield/Lumigraph 4D
• Concentric Mosaics 3D
• Panorama 2D

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Pros and Cons

• Pros
• Neednt recover geo/photometrics
• More movement than
• Small file size
• Computational efficiency
• Easy to capture, construct
• Cons
• Cannot add lights, shadows, etc.
• Less movement than

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Overview of Process

• Take pictures, indexed by
• Radius of circle
• Rotation angle
• Vertical elevation
• Perform depth correction
• Render novel view

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1. Take Pictures

• Synthetic scenes
• Concentric circles
• Real scenes
• Swing mosaic

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2. Depth Correction

• Problem vertical distortion
• Solution
• Full perspective correction
• Weak perspective correction
• Constant depth approximation

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Full Perspective Correction

• Preconditions
• Distance from camera to point
• Action
• Warp from captured ray to novel ray using optical
  flow
• Pros
• Yields correct novel views for synthetic scenes
• Cons
• Geometries arent usually known for real scenes
• Hole-filling problems still exist

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Weak Perspective Correction

• Preconditions
• Pixels from vertical line have same depth
• Action
• Estimate depth of each vertical line
• Scale line uniformly
• Pros Cons
• Distortion is proportional to distance
• Proportional to depth variation in vertical line

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Constant Depth Approx.

• Preconditions
• Depth is constant for all vertical lines
• Action
• Scale line by depth value
• Pros Cons
• (see weak perspective correction)

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3. Render Novel View

• Match novel rays to captured rays
• Bilinearly interpolate when necessary