“Seeing" machines and "intelligent" robots have been the focus of research on Automated Processing Industries and in Autonomous Ground Vehicle. A goal is to gain a basic understanding of vision, as a powerful means of perception, autonomy and intelligence of technical systems, and to construct seeing intelligent robots. These should be able to operate robustly and at an acceptable speed in the real world, to survive in a dynamically changing natural environment, and to perform autonomously a wide variety of tasks. This paper reports about a  essential preprocessing step of Imaging system as image rectification, a widely used technique in 3Dreconstruction and stereo vision, that have been developed during recent research projects for automating. Image rectification is a transformation process used to project multiple images onto a common image surface. It is used to correct a distorted image into a standard coordinate system. The important advantage of rectification is that computing stereo correspondences is reduced to a 1-D search problem along the horizontal raster lines of the rectified images. This Paper describes about a linear rectification algorithm through a non-linear transformation technique for general, unconstrained stereo rigs. The algorithm requires the two perspective projection matrices of the original cameras, and enforces explicitly all constraints necessary and sufficient to achieve a unique pair of rectifying projection matrices.

Key words:Stereo image, Epipolar geometry, Image rectification, Epipolar Constraint