Performance of correlation-based stereo algorithm with respect to the change of the window size

Abstract

Correlation-based stereo matching is very important to the generation of 3D terrain model. One of the difficulties in this stereo matching is the selection of the window size, since there are two competing factors that must be balanced in any stereo reconstruction process - perspective distortion and stereo matching error. This paper presents how the correlation window size affects the accuracy of stereo matching and suggests a tool to tune the window size in a given image domain. To facilitate the analysis proposed in this paper, we use photo-realistic simulation methodology to generate a pair of photo-realistic synthetic images of the terrain from a pre-acquired DEM(Digital Elevation Map) and ortho-image, which can be served as the pseudo ground truth. We performed 3D reconstruction on synthetic images of a natural terrain with Terrest system and carried out the evaluation of the correlation window on DEM accuracy. Experimental results are consistent with our strong expectation about two competing factors and show that our approach can be a useful tool to tune the window size. © Springer-Verlag Berlin Heidelberg 2004.