... involved¹

These steps include difficult problems such as segmentation, recognition, correspondence, etc.

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... solution²

More specifically, three orthographic views are used and the solution is unique up to a reflection.

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... image.³

Thus, once F is solved, finding further corresponding points given a location in one image is reduced to searching along the epipolar line instead of the whole image.

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... system:⁴

Note, more generally, all matrices can vary as functions of the state ${\bf x}$ and with time t.

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... parameters⁵

These encode the relative 3D rotation and the 3D translation between the camera and the scene.

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... sensor⁶

The Polhemus sensor is physically attached to the head

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