Using the Radon Transform to detect anisotropic error sources

Gerald Dibarboure (CLS, France)


Jean-Christophe Poisson (CLS, France)

Event: 2014 Ocean Surface Topography Science Team Meeting

Session: Quantifying Errors and Uncertainties in Altimetry data

Presentation type: Type Poster

The Radon Transform (RT) is a simple processing technique that can provide an estimate of the angle and intensity of aligned structures (isolated or harmonic features) in an image or any bi-dimensional array. It also helps quantify the (an)isotropy of the image itself.

The Radon Transform has been used in the context of radar altimetry with the objective of understanding oceanic processes (e.g. velocity of Rossby waves in Hovmöller diagrams).

Instead, we illustrate the RT's capability to detect and quantify errors and sampling limitations with two very different examples. Firstly, we illustrate the anisotropic sampling capability of AVISO/DUACS maps where the discrepancy between the along and across track resolution is visible in the angular variance of the Radon Transform. Secondly, we show that the RT can provide valuable insights on the anisotropy of geographically coherent errors sources in simulated 2D images from the future SWOT mission.
Gerald Dibarboure