Figure 5.
(a) Motion field estimation error maps of the registration frame #5 → frame #1 with and without regularization using the tagged-MRI simulations with 5% and 25% noise levels. (b) Lower torso and upper torso profiles through these error maps. The estimation error is the greatest in the lungs, where it is in fact equal to the opposite of the reference displacement, since motion is not estimated in these regions.