We illustrate the ability of the method to ignore parasitical data on the presented diagnostic sequence.
This case involves a contrast injection in the coronaries through a catheter. The image follows a two-layers configuration,
there including the heart and lungs tissues.
The estimated displacements are directed toward the past to respect the notations of the Transparent Motion Constraint.
As a result they are in the opposite direction compared to the usual represented velocity direction.
Estimation result at four interesting time instants
On the first presented frame, before the injection, the motion of the two layers is satisfactory estimated.
In particular, the motion of the catheter is corretly associated with the heart layer.
The second image displays the ongoing injection. The evolving contrast product does not disturb the motion estimation
method on the presented example thanks to the robust function used.
This situation is still difficult, and leads sometimes to erroneous estimations, as can be seen on the overall sequence.
Once the injection is stabilized, far from impairing the motion estimation, it actually helps it by making
the heart layer more textured.
Whole processed sequence
We also present the overall processed sequence. It shows the estimated affine motion fields, along with the corresponding
frames.
The results are satisfactory for about 60% of time instants. Most erroneous estimations occur mostly because of the abrupt
nature of the coronary motions, which implies the motion constancy assumption is frequently violated.
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