Depth estimation and 3D topography reconstruction from SAR images showing underwater bottom topography signatures

We propose a simple algorithm for the estimation of underwater bottom topography from synthetic aperture radar images (SAR). The algorithm has three steps. First, we smooth the SAR image using the anisotropic diffusion approach. Second, we estimate surface current gradients by inversion of the linear kernel of the Volterra model of the forward imaging mechanism. Finally, we obtain depth values by means of a continuity equation. The results show that this algorithm can give a good description of the form of the bottom topography, but a priori knowledge about the scene (mean surface current value, wind speed, etc...) is needed if we want to obtain a calibrated elevation model.