INTERPOLATION ARTIFACTS IN BIOMEDICAL IMAGE REGISTRATION

We identify a cause for interpolation artifacts in objective functions by observing that the energy of interpolated and translated l
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sequences oscillates with respect to the translation parameter. Using the B-spline interpolation framework, we show that such oscillations in the energy of the signals affect the sum of squared differences, cross correlation, and mutual information objective functions. We describe several approaches that can be used to avoid interpolation artifacts (such as higher degree interpolation, as well as stochastic sampling) and explain in detail why these are effective in eliminating the artifacts