The Application of Active Contours for the Localization of Varying-contrast Edges in Synthetic Aperture Radar Images

Over the last years, active contour methods have become a basic tool in computer vision. They have proven to be efficient for various image processing applications, like reconstruction of the edges inside images or the tracing of image features. However, when applying the basic snake technique to synthetic aperture radar (SAR) remote sensing images, the reconstruction of edges may not be satisfying. This is caused by the special imaging technique of SAR that may tend to produce varying-contrast edges and the commonly known speckle noise. In [4] we proposed the use of asymmetric external energy terms to cope these problems. In this paper we will summarize the lessons learned in the previous work, where we applied the technique to detect edges of tidal creeks using an ENVISAT ASAR image. These creeks can e.g. be found in the UNESCO World Heritage Site ”Wadden Sea” located at the German Bight (North Sea). In addition, we describe the challenges and opportunities that could be achieved when using hi-resolution TerraSAR-X data instead of the ASAR data. We have just applied for some TerraSAR-X hi-resolution images and are looking forward to practically demonstrate the advantages for this special class of images.