Pavement Cracks Detection Based on NSCT and Morphology

The complex nature of road images and weak signal make the detection pavement cracks particularly difficult.An algorithm for pavement cracks detection based on nonsubsampled contourlet transform(NSCT) and morphology is proposed.Firstly,the coefficients at different scales and in different directions are obtained by image decomposition using the NSCT,then coefficients thresholds are adaptively set and the generalized nonlinear gain function is used to enhance the features with low contrast while preventing the strong contrast features from over enhancing in the NSCT domain.After the enhancement,the inverse transform is performed,and morphological and median filters are employed to detect cracks and remove noise.The proposed algorithm is tested by real highway pavement images.The experimental results show that our algorithm is more robust and effective to detect road cracks especially for weak contrast cracks and thin cracks than other algorithms,such as histogram enhancement,wavelet transform,or contourlet transform.