$$To have a more precise view of errors, Figure \ref{fig:errors}(a), (b) and (c) demonstrates the absolute errors of the rigid body translation, rotation and uniaxial tensile conditions, respectively. Figure \ref{fig:errors}(a) shows that the absolute error of the transversal and axial displacement components approximately follows a sinusoidal curve and that both components have the displacement errors close to zero at the simulated displacement of 0.5 pixel, as reported by the literature \cite{schreier2000}. The standard deviations for 10 increments are almost at same level. The overall error in the DIC-computed displacements falls between $-0.001$ to $0.001$ pixel which equals to 1\% of relative error at its maximum.$$