Mimas Camera Calibration

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=Calibration=
 
=Calibration=
[[Image:working.gif]] Under construction ...
 
 
 
Let <math>\vec{m}_i\in\mathbb{R}^3,\,i\in\{1,2,\ldots,N\}</math> be the [http://en.wikipedia.org/wiki/Homogeneous_coordinates#Use_in_computer_graphics homogeneous coordinate] of the <math>i</math>th point on the planar calibration-object and let <math>\vec{m}^\prime_i\in\mathbb{R}^3</math> be the homogeneous coordinate of the corresponding pixel in the camera-image. Further let <math>(\mathbb{R}^n,\simeq)</math> be an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] defined by
 
Let <math>\vec{m}_i\in\mathbb{R}^3,\,i\in\{1,2,\ldots,N\}</math> be the [http://en.wikipedia.org/wiki/Homogeneous_coordinates#Use_in_computer_graphics homogeneous coordinate] of the <math>i</math>th point on the planar calibration-object and let <math>\vec{m}^\prime_i\in\mathbb{R}^3</math> be the homogeneous coordinate of the corresponding pixel in the camera-image. Further let <math>(\mathbb{R}^n,\simeq)</math> be an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] defined by
  
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\begin{pmatrix}m_{i1}\\m_{i2}\\m_{i3}\end{pmatrix}
 
\begin{pmatrix}m_{i1}\\m_{i2}\\m_{i3}\end{pmatrix}
 
</math>
 
</math>
 
 
with <math>\vec{m}^\prime_i=\widehat{\vec{m}}_i+\vec{\epsilon}_i</math>.
 
with <math>\vec{m}^\prime_i=\widehat{\vec{m}}_i+\vec{\epsilon}_i</math>.
  
The [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] <math>(\mathbb{R}^n,\simeq)</math> is defined by
+
Using <math>m_{i3}=m^\prime_{i3}=\widehat{m}_{i3}=1</math> and <math>\vec{h_i}^\top=\begin{pmatrix}h_{i1}&h_{i2}&h_{i3}\end{pmatrix},\ i\in\{1,2,3\}</math> the
 
+
model can be represented by
<math>
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\vec{a}\simeq\vec{b}\ :\Leftrightarrow\ \exists\lambda\in\mathbb{R}/\{0\}:\,\lambda\,\vec{a}=\vec{b}
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</math>
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<math>
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\lambda\widehat{\vec{m}}_i=\mathcal{H}\vec{m}_i
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</math>
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<math>
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\lambda\,\begin{pmatrix}\widehat{m}_{i1}\\\widehat{m}_{i2}\\\widehat{m}_{i3}\end{pmatrix}=
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\begin{pmatrix}h_{11}&h_{12}&h_{13}\\h_{21}&h_{22}&h_{23}\\h_{31}&h_{32}&h_{33}\end{pmatrix}\,
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\begin{pmatrix}m_{i1}\\m_{i2}\\m_{i3}\end{pmatrix}
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</math>
+
 
+
<math>
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\vec{h_i}^\top=\begin{pmatrix}h_{i1}&h_{i2}&h_{i3}\end{pmatrix},\ i\in\{1,2,3\}
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</math>
+
 
+
 
<math>
 
<math>
 
\begin{pmatrix}\widehat{m}_{i1}\\\widehat{m}_{i2}\end{pmatrix}=
 
\begin{pmatrix}\widehat{m}_{i1}\\\widehat{m}_{i2}\end{pmatrix}=
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\begin{pmatrix}m_{i1}\\m_{i2}\\1\end{pmatrix}+
 
\begin{pmatrix}m_{i1}\\m_{i2}\\1\end{pmatrix}+
 
\vec{\epsilon_i}
 
\vec{\epsilon_i}
</math>
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</math>.
 +
 
 +
[[Image:working.gif]] Under construction ...
  
 
Other symbols:
 
Other symbols:

Revision as of 21:34, 25 June 2006

Calibration

Let <math>\vec{m}_i\in\mathbb{R}^3,\,i\in\{1,2,\ldots,N\}</math> be the homogeneous coordinate of the <math>i</math>th point on the planar calibration-object and let <math>\vec{m}^\prime_i\in\mathbb{R}^3</math> be the homogeneous coordinate of the corresponding pixel in the camera-image. Further let <math>(\mathbb{R}^n,\simeq)</math> be an equivalence relation defined by

<math> \vec{a}\simeq\vec{b}\ :\Leftrightarrow\ \exists\lambda\in\mathbb{R}/\{0\}:\,\lambda\,\vec{a}=\vec{b} </math>

If the camera-system does an ideal central projection (e.g. no distortion), the projective transformation (the Homography) can be modelled using <math>\mathcal{H}\in\mathbb{R}^{3\times 3}</math> as follows

<math> \widehat{\vec{m}}_i\simeq\mathcal{H}\vec{m}_i </math> or more elaborately <math> \lambda\,\begin{pmatrix}\widehat{m}_{i1}\\\widehat{m}_{i2}\\\widehat{m}_{i3}\end{pmatrix}= \begin{pmatrix}h_{11}&h_{12}&h_{13}\\h_{21}&h_{22}&h_{23}\\h_{31}&h_{32}&h_{33}\end{pmatrix}\, \begin{pmatrix}m_{i1}\\m_{i2}\\m_{i3}\end{pmatrix} </math> with <math>\vec{m}^\prime_i=\widehat{\vec{m}}_i+\vec{\epsilon}_i</math>.

Using <math>m_{i3}=m^\prime_{i3}=\widehat{m}_{i3}=1</math> and <math>\vec{h_i}^\top=\begin{pmatrix}h_{i1}&h_{i2}&h_{i3}\end{pmatrix},\ i\in\{1,2,3\}</math> the model can be represented by <math> \begin{pmatrix}\widehat{m}_{i1}\\\widehat{m}_{i2}\end{pmatrix}= \cfrac{1}{\vec{h_3}^\top\cdot\vec{m}_i}\, \begin{pmatrix}\vec{h_1}^\top\\\vec{h_2}^\top\end{pmatrix}\, \begin{pmatrix}m_{i1}\\m_{i2}\\1\end{pmatrix}+ \vec{\epsilon_i} </math>.

Working.gif Under construction ...

Other symbols: <math> \vec{0}, \neq, ||\mathcal{A}||, \mathcal{A}\in\mathbb{C}^{3\times 3}, i\in\mathbb{N}_0,0\approx 1, \begin{pmatrix}1-\lambda&0\\0&1-\lambda\end{pmatrix}, \mathbb{R}^3, i\in\{1,2,\ldots,n\}</math>

<math> \begin{pmatrix}1-\lambda&0&\cdots&\cdots&0\\0&1-\lambda&\ddots&&\vdots\end{pmatrix},V^*,a*b, \sigma, \Sigma, \lambda, \Lambda</math>

<math> \sum_{i=1}^n p^i, \prod_{i=1}^{+\infty}a_i, \cos(\omega), \widehat{i}=\mathrm{argmax}_{i\in\mathbb{N}}f(i), a\simeq b </math>


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