 The Birchfield–Tomasi measure compensates for the sampling effect by considering the linear interpolation of the samples.Pixel similarity is then determined by finding the best match between the intensity of a pixel sample in one image and the interpolated function in an interval around a location in the other image.Considering the stereo matching problem for a rectified stereo pair, where the search for correspondences is performed in one dimension, given two columns formula_1 and formula_2 along the same scanline for the left and right image respectively, it is possible to define two symmetric functions
where formula_4 and formula_5 are the linear interpolation functions of the left and right image intensity formula_6 and formula_6 along the scanline.