NSCT edge Enhancement for SIFT key points extraction
Résumé
Image registration is a key step for matching or mosaicing two or more images taken at different times, and/or with different sensors, hence the need for automatic methods arises. In this work, we present an efficient registration method based on the Non-Subsampled Contourlet Transform (NSCT) combined with the Scale Invariant Feature transform (SIFT) to extract robust local control points. Because NSCT is a shift-invariant multidirectional transform, it is used to extract edges at both spatial and directional resolutions. A comparative study is established between SIFT and NSCT-SIFT and experimental results show clearly that the proposed method (NSCT-SIFT) improves the registration accuracy.