# Analysis and Computation of Projective Invariants from Multiple Views in the Geometric Algebra Framework

@article{Lasenby1999AnalysisAC, title={Analysis and Computation of Projective Invariants from Multiple Views in the Geometric Algebra Framework}, author={Joan Lasenby and Eduardo Bayro-Corrochano}, journal={Int. J. Pattern Recognit. Artif. Intell.}, year={1999}, volume={13}, pages={1105-1122} }

A central task of computer vision is to automatically recognize objects in real-world scenes. The parameters defining image and object spaces can vary due to lighting conditions, camera calibration and viewing positions. It is therefore desirable to look for geometric properties of the object which remain invariant under such changes. In this paper we present geometric algebra as a complete framework for the theory and computation of projective invariants formed from points and lines in…

## 27 Citations

A Geometric Approach for the Theory and Applications of 3D Projective Invariants

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This paper uses a monocular omnidirectional vision system to extract the image features and the conformal geometric algebra to compute the projective invariants from such features, and shows how these features can be used to compute projective and permutation p2-invariants from any kind of omnid directional vision system.

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A series of calibration techniques which use all of the available data simultaneously and produce accurate reconstructions with no complicated calibration equipment or procedures are outlined.

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