All traditional photographs are merely flat projections of three dimensional objects and thus often are unable to convey the complexity of object shapes, appearances, and orientation in real space. Threedimensional models of the objects, in contrast, carry valuable information on the true object shapes, aspect ratios, and (in some cases) color gradients and textures. Industrial applications often use high-end laserbased scanning coordinate measurement machines (CMMs) to produce three

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... models of the objects for reverse engineering, metrology, and for quality control in mass production. For less demanding applications or when the specialized equipment is unavailable, photogrammetry may become a low cost alternative to CMMs. Photogrammetry is a technique that allows for reconstruction of three-dimensional model of the object from a series of overlapping images of the object taken at multiple angles, rotations, tilts and magnifications. Photogrammetry is based on the concept that the location of each point on the object in space can be mathematically derived from planar projections of the point taken from two different viewing angles [1] [2] .