1. A method for determining a disparity vector for a pixel in a right image corresponding to a pixel in a left image in a pair of stereo images, wherein the disparity vector is based on a horizontal disparity and a vertical disparity and the pair of stereo images is unrectified, comprising the steps of: determining a set of candidate horizontal disparities; calculating, for each candidate horizontal disparity, a cost associated with a particular horizontal disparity and corresponding vertical disparities; assigning the vertical disparity associated with a first optimal cost to each candidate horizontal disparity, wherein the candidate horizontal disparity and the vertical disparity yield a candidate disparity vector; and selecting the candidate disparity vector with a second optimal cost as the disparity vector of the pixel in the right image.