CAP5415 Computer Vision Spring 2003

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CAP5415 Computer VisionSpring 2003

• Khurram Hassan-Shafique

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Camera Parameters
Y
M
Image plane
C
Z
X
Focal plane
m
From Perspective Projection
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Camera Parameters
Y
M
Image plane
C
Z
v
X
Focal plane
m
u
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Camera Parameters
Equation 3
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Camera Parameters
Equation 1
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Camera Parameters
Equation 4
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Camera Parameters
Intrinsic Parameters (Do not depend on camera
position)
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Intrinsic Parameters
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Calculating Camera Center (from Intrinsic
Parameters)
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Extrinsic Parameters
Y
M
Image plane
Y
C
Z
v
X
X
Z
Focal plane
m
u
By Rigid Body Transformation
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Camera Model
12
Camera Model
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Suggested Reading

• Chapter 3, Olivier Faugeras, "Three Dimensional
  Computer Vision", MIT Press, 1993
• Chapter 2, David A. Forsyth and Jean Ponce,
  "Computer Vision A Modern Approach"
• Chapter 1, Mubarak Shah, "Fundamentals of
  Computer Vision"

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Estimating Camera Parameters
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Estimating Camera Parameters
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Estimating Camera Parameters
Compute v by SVD decomposition of AUDVT (The
solution vector is the column of V corresponding
to null (or smallest) singular value) in D.
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Estimating Camera Parameters
Computing Scale Factor
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Estimating Camera Parameters
Computing
Computing Sign of
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Estimating Camera Parameters
Computing third row of Rotation Matrix
Computing
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Estimating Camera Parameters
Computing Image Center
Let T be a triangle on the image plane defined by
the three Vanishing points of three mutually
orthogonal sets of Parallel lines in space. The
image center is the orthocenter of T
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Suggested Readings

• Chapter 6, Emanuele Trucco, Alessandro Verri,
  "Introductory Techniques for 3-D Computer
  Vision", Prentice Hall, 1998
• Chapter 1, Mubarak Shah, "Fundamentals of
  Computer Vision"