Most image rendering methods try to mimic real cameras by generating images having the perspective projection. In contrast, a unique power of image mosaicing is the ability to generate new views with "impossible" projections which are not perspective. This can be done with mosaicing methods that construct a panoramic mosaic image by stitching together narrow strips, each strip taken from a different source image. A different selection of strips gives a different mosaicing effect using the same set of source images.

For example, given a sequence of source images from a camera moving sideways, a set of mosaic images can be generated providing a virtual walkthrough in the scene, including forward(!) motion. And this is done without recovering any 3D geometry and without calibration. In another example, a set of full panoramic stereo views can be generated, even though perspective cameras allow only a very narrow view for stereo images.

The power of mosaicing to generate such "impossible" views is a result of the new family of scene to image projections that can be constructed. These projections, the "Crossed Slits" projections, will be defined and analyzed together with the appropriate mosaicing. -