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arXiv · 2110.03337

Moment evolution equations and moment matching for stochastic image EPDiff

Alexander Christgau·Alexis Arnaudon·Stefan Sommer
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Abstract

Models of stochastic image deformation allow study of time-continuous stochastic effects transforming images by deforming the image domain. Applications include longitudinal medical image analysis with both population trends and random subject specific variation. Focusing on a stochastic extension of the LDDMM models with evolutions governed by a stochastic EPDiff equation, we use moment approximations of the corresponding It\^o diffusion to construct estimators for statistical inference in the full stochastic model. We show that this approach, when efficiently implemented with automatic differentiation tools, can successfully estimate parameters encoding the spatial correlation of the noise fields on the image.

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Alexander Christgau, Alexis Arnaudon, Stefan Sommer. 2021-10-07. Moment evolution equations and moment matching for stochastic image EPDiff. https://arxiv.org/abs/2110.03337

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