Camera Parameters: Difference between revisions
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==Extrinsics== | ==Extrinsics== | ||
This is the view matrix which encodes the camera's position and rotation. | This is the view matrix which encodes the camera's position and rotation. | ||
Suppose the camera position is \(\mathbf{C}\) and rotation \(\mathbf{R}_c\). | |||
\[ | \[ | ||
\begin{equation} | \begin{equation} | ||
M_{ext}= [\mathbf{R} | \mathbf{t}] | M_{ext}= [\mathbf{R} | \mathbf{t}] = [\mathbf{R}_c^T | -\mathbf{R}_c^TC] | ||
\end{equation} | \end{equation} | ||
\] | \] | ||
Revision as of 18:41, 18 June 2020
Camera Parameters
Intrinsics
The is the projection matrix which turns camera coordinates to image coordinates.
It consists of the following:
- Focal Length \(f\)
- Image Center \(\mathbf{o} = (o_x, o_y)\)
- Size of pixels \(\mathbf{s} = (s_x, s_y)\)
- Axis skew \(s\) typically 0
The formula for this matrix is: \[ \begin{equation} M_{int} = \begin{bmatrix} -f/s_x & s & o_x\\ 0 & -f/s_y & o_y\\ 0 & 0 & 1 \end{bmatrix} \end{equation} \]
Extrinsics
This is the view matrix which encodes the camera's position and rotation.
Suppose the camera position is \(\mathbf{C}\) and rotation \(\mathbf{R}_c\).
\[ \begin{equation} M_{ext}= [\mathbf{R} | \mathbf{t}] = [\mathbf{R}_c^T | -\mathbf{R}_c^TC] \end{equation} \]