Fig. 5.

Displacement components, u_x (a) and u_y (b), recovered from OF and their corresponding difference images relative to the ground truth (c and d, respectively) for the synthetic data shown in Fig. 4. An area in which the difference magnitude was >0.5 pixel is also shown (thin line in d). The “width” of the band of pixels with relatively poor displacement accuracy near the craniotomy rim was approximately 40 pixels, similarly to the maximum displacement in this region.