For the sake of completeness, Euclidean geometry is briefly discussed. It does not differ much from metric geometry as we have defined it here. The difference is that the scale is fixed and that therefore not only relative lengths, but *absolute lengths* can be measured. Euclidean transformations have 6 degrees of freedom, 3 for orientation and 3 for translation. A Euclidean transformation has the following form

(B40) |

Marc Pollefeys 2002-11-22