SplineCubicCoef( vector, h )

This function computes the coefficient values of the cubic polynome between two neighboring pixel values. The input is a vector of the values of the pixels of each row/column. Through this function we can compute approximations of the pixel values in between the two neighboring ones we are taking into account. The output is a vector as well, containing the four coefficient values for each approximative cubic polynomes. The resizing factor is defined by h.