1. A method for feature-front based stereo matching image processing utilizing a computer-based device, the method comprising: providing at least one left image having at least one scanline and at least one right image having at least one scanline of an object or scene, wherein each scanline has at least one extremal pixel; optionally converting the left image and right image to grey scale images; optionally smoothing the left and right image; finding the extremal pixels along each scanline in each image by calculating at each pixel the product of the along-the-scanline backward and forward differences of the image intensity field, whereby a pixel is an extremal pixel when the product is less than zero or when the product is zero and either the backward or forward difference is non-zero and wherein two consecutive image intensity extrema are connected by a straight line to form an ascending or descending feature front, for the left image and for the right image, having a strength equal to the absolute difference between the feature front end intensity values; utilizing the scanlines from the left image and right image simultaneously and sorting the feature fronts in decreasing order of strengths greater than a value of zero into a list; and calculating for each front in the sorted list, in order of strongest to weakest feature front regardless of scanline, the matching front on the other scanline within a search window satisfying the match criterion, wherein the feature front for which a match is sought is the current feature front.