“…with s(ξ, t) the pixel value of the binary image and (ξ, t) an adaptive threshold calculated at each pixel ξ individually by computing the cross-correlation with a Gaussian window [30] over the neighbourhood of ξ minus a constant C. The neighbourhood is defined by a quadratic structuring element [31] of size 15 × 15 pixels with ξ in the center and C = V Z (0, t) is the gray scale of the upper left corner. Using the normalized values of s(ξ, t) we evaluate the moving average ψ(x) = x ξ at pixel ξ expressed by 1…”