Multiresolution analysis with decimated wavelet transform for image zooming
Frédéric Nicolier, Frédéric Truchetet · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2000
Blurred images are produced by interpolation process. A wavelet-based magnification method is proposed that both increases the resolution of an image and adds local high- frequency information, in order to provide digitally zoomed images with sharp edges. Wavelet transforms computed by the decimated Mallat's algorithm present pyramidal aspect. This pyramidal analysis combined with a prediction of high- frequency coefficients is used to produce a magnified image. The prediction is based on a zero-crossings representation and on the construction of a multiscale edge-signature database. Performances are evaluated for synthetic and noisy images. A significant improvement regarding some classical methods is observed.