Fig. 8From: A new method for detecting the outer corneal contour in images from an ultra-fast Scheimpflug cameraThe sum of pixels in the shaded square ABCD, with the coordinates \(A\left( {m - w,n - w} \right)\), \(B\left( {m - w,n} \right)\), \(C(m,n - w)\), \(D\left( {m,n} \right)\), representing the window sized \(w \times w\), can be calculated using the value of the integral image \(L_{i} \left( {m,n} \right)\) as follows: \(D + A - B - C = 36 + 1 - 10 - 7 = 20\)Back to article page