The Dual-Tree Complex Wavelet Transform – A Coherent Framework for Multiscale Signal and Image Processing
نویسندگان
چکیده
The dual-tree complex wavelet transform (CWT) is a relatively recent enhancement of the discrete wavelet transform (DWT) with important additional properties: It is nearly shift-invariant and directionally selective in two and higher dimensions. It achieves this with a redundancy factor of only 2 for d-dimensional signals, which is substantially lower than the undecimated DWT. The multidimensional dual-tree CWT is non-separable but is based on a computationally efficient, separable filter bank. This tutorial discusses the theory behind the dual-tree transform, shows how complex wavelets with good properties can be designed, and illustrates a range of applications in signal and image processing.
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