Spatiotemporal tomography based on scattered multiangular signals and its application for resolving evolving clouds using moving platforms
This work addresses the challenge of accurately reconstructing dynamic clouds, which is important for climate modeling, by overcoming limitations of existing static or linear 4D CT methods.
The paper tackles the problem of reconstructing time-varying volumetric translucent objects, specifically dynamic clouds, using a small number of moving cameras and scattered multiangular signals. It derives a computed tomography (CT) approach for this non-linear problem, leading to a representation of the time-varying object that simplifies 4D CT tomography.
We derive computed tomography (CT) of a time-varying volumetric translucent object, using a small number of moving cameras. We particularly focus on passive scattering tomography, which is a non-linear problem. We demonstrate the approach on dynamic clouds, as clouds have a major effect on Earth's climate. State of the art scattering CT assumes a static object. Existing 4D CT methods rely on a linear image formation model and often on significant priors. In this paper, the angular and temporal sampling rates needed for a proper recovery are discussed. If these rates are used, the paper leads to a representation of the time-varying object, which simplifies 4D CT tomography. The task is achieved using gradient-based optimization. We demonstrate this in physics-based simulations and in an experiment that had yielded real-world data.