A wavelet transform based method for road centerline extraction

This paper introduces a new wavelet transform based method of road centerline extraction from high resolution remote sensing images. In the one dimensional case, we characterize different kinds of sudden changes of signals by comparing the magnitudes of the local extreme values of the wavelet transforms under different dilation scales of the some wavelet. The Platform-like signals, which come from cross sections of roads, con be characterized through the evolution of the wavelet transform across scales. A two-dimensional wavelet transform of an image consists of two components, each component is a one dimensional wavelet transform in one coordinate direction followed by a smoothing process in the perpendicular direction. The road edges can be characterized through the evolution of the two-dimensional wavelet transform across different scales. Edges of the main roads can then be extracted using these characterizations, and the road centerlines con be obtained by proper post-processing.