1

CAP5415 Computer VisionSpring 2003

Khurram Hassan-Shafique

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Camera Parameters

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7

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"

Estimating Camera Parameters

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8

Estimating Camera Parameters

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( ) ( )iiiii ZYXvu ,, and ,pair ingcorrespondeach For

secondby equation first thedividing and 0 and Let 00 === vuf

f

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Estimating Camera Parameters( ) ( )iiiii ZYXvu ,, and ,pair ingcorrespondeach For

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9

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( )TXY TrrrTrrr�v

v

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thenector,solution v obtained thebeLet

=

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rrrvvv

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rrr

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signs theReverse

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10

Estimating Camera ParametersComputing third row of Rotation Matrix

213 rrr ×=

Computing Zvu Tff and ,

( ) ( ) ( ) ( )( ) ( ) ( ) ( )( )XW

iW

iW

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bf

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Estimating Camera Parameters Computing Image Center ( )00 ,vu

Let T be a triangle on the image plane defined by the threeVanishing points of three mutually orthogonal sets of Parallel lines in space. The image center is the orthocenter of T

11

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"