Essential Matrix: Difference between revisions

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* This matrix is skew-symmetric. I.e. <math>[\mathbf{t}]^T_{\times} = -[\mathbf{t}]_{\times}</math>  
* This matrix is skew-symmetric. I.e. <math>[\mathbf{t}]^T_{\times} = -[\mathbf{t}]_{\times}</math>  


Given feature points <math>\mathbf{x}</math> and <math>\mathbf{x'}</math> from two images,
Now if <math>\mathbf{u}'</math> is a feature point from camera 2 matching point <math>\mathbf{u}</math>, then it must lie on this epipolar line.
we can relate them with a rotation <math>\mathbf{R}</math> and a translation <math>\mathbf{t}</math>  
Thus <math>\mathbf{u}' \in \{(u',v',w') \mid pu' + qv' + rw' = 0\} \implies \mathbf{u}'^T R[T]_{\times} \mathbf{u} = 0</math>.
such that <math>(\mathbf{R}\mathbf{x} + \mathbf{t}) = x'</math>.
Now <math>Q = R[T]_{\times}</math> is the essential matrix.
 
Given 8 or more correspondence points between camera 1 and camera 2, you can solve for <math>Q</math> using the [[Wikipedia: Eight-point algorithm]]


==Properties==
==Properties==