artifacts on the reconstructed images. This drawback can be alleviated using
a shift-invariant wavelet transform, such as the undecimated DWT [23].
7.6.3 Extended Depth-of-Field by
Wavelet Image Fusion
Wavelet image fusion is a technique of combining, in the wavelet domain,
information from multiple registered images to form a single image. Image
fusion techniques have been particularly popular in medical imaging, where
different modalities are used to capture different information, and in multi-
spectral imaging for remote sensing. When imaging a specimen that is thicker
than the depth-of-field (DOF) of a microscope, only a portion of the specimen is
in focus at any one time, while other areas are blurred because of the point
spread function. To image ...