River detection algorithm in SAR images based on edge extraction and ridge tracing techniques

This article presents a novel river detection algorithm in synthetic aperture radar (SAR) images. It is based on edge extraction in the wavelet domain followed by ridge tracing to merge the water region. The edge detection is approached by direct spatial correlation of wavelet transform data at several adjacent scales. For the ridge tracing algorithm, the concept used in fingerprint identification is introduced to complete riverbank linking and connecting based on a greyscale image. This improvement avoids the disadvantages of the widely used snake model in coastline connection. As indicated by the river detection results from the real SAR images, our river detection algorithm is efficient and robust in detecting the river in complicated suburb and nature water areas.