Shift invariant properties of the dual-tree complex wavelet transform
نویسنده
چکیده
We discuss the shift invariant properties of a new implementation of the Discrete Wavelet Transform, which employs a dual tree of wavelet lters to obtain the real and imaginary parts of complex wavelet co-eecients. This introduces limited redundancy (2 m :1 for m-dimensional signals) and allows the transform to provide approximate shift invariance and directionally selective lters (properties lacking in the traditional wavelet transform) while preserving the usual properties of perfect reconstruction and computational ee-ciency with good well-balanced frequency responses.
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