22 lines
1.4 KiB
TeX
22 lines
1.4 KiB
TeX
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% Here we go
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\subsection{Camera calibration}
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The camera calibration is needed by the client during the reconstruction of the 3D skeleton. The calibration consists in two steps :
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\begin{enumerate}
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\item the \textbf{internal calibration} which is the estimation of the instrinsic parameters of the camera (such as the focal length, or the
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principal point)
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\item the \textbf{external calibration} which is the estimation of the
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extrinsic parameters (the position of the camera from the chessboard)
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\end{enumerate}
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\subsubsection{Internal calibration}
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The internal calibration is based on a program that we completed during a lesson last semester. By detecting chessboards from numerous positions of the camera, we are able to estimate the intrinsic parameters. This program takes as input a video of a chessboard where the camera position changes, and it captures some frames on which the chessboard is detected. With these pictures, we estimate the intrinsic parameters.
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\subsubsection{External calibration}
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For the external calibration, we wrote a program that uses an
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estimation of the homography to compute the extrinsical parameters of
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the camera. One should note that what we call the \emph{extrinsical
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parameters} are the ones that convert points from the reference of the
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chessboard to the reference of the camera.
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