Reconstruction techniques, such a stereography, are easily deduced from a geometric model of the pinhole camera as a set of rays passing through a point. Given two 2D retinal points, consider the two corresponding rays passing through it (using inverse projection): Their intersection means that both points are in stereographic correspondance.

In this work, we extend such an application to a class of central and non-central imaging devices, called \emph{linear cameras}, that subsumes pinhole, pushbroom, X-slit, pencil and linear oblique cameras. We propose for that a unified model from which we derive closed-form formulas for projection and stereo-correspondance between \emph{any} pair of linear cameras. The main ingredient is a decomposition of a camera into a retina and a bag of lines, the latter being represented by a linear \emph{admissible map} that globally preserves any line of that bag.