Best Basis Algorithm for Orthonormal Shift-Invariant Trigonometric Decomposition
نویسندگان
چکیده
The Local Cosine Decomposition of Coifman and Wickerhauser 1] is modiied by incorporating two degrees of freedom that increase the adaptability of the best basis. These are relative shifts between resolution levels and adaptive polarity foldings. The resultant expansion is shift-invariant, and yields adaptive time-frequency distributions which are characterized by high resolution, high concentration and suppressed cross-terms associated with the Wigner distribution .
منابع مشابه
Orthonormal shift-invariant adaptive local trigonometric decomposition
In this paper, an extended library of smooth local trigonometric bases is defined, and an appropriate fast “best-basis” search algorithm is introduced. When compared with the standard local cosine decomposition (LCD), the proposed algorithm is advantageous in three respects. First, it leads to a best-basis expansion that is shift-invariant. Second, the resulting representation is characterized ...
متن کاملShift - Invariant Adaptivelocal Trigonometric
A general formulation of shift-invariant \best-basis" expansions is presented. Speciically, we construct an extended library of smooth local trigonometric bases, and introduce a suitable \best-basis" search algorithm. We prove that the resultant decomposition is shift-invariant, orthonor-mal and characterized by a reduced information cost. The shift-invariance is derived from an adaptive relati...
متن کاملShift Invariant Wavelet Packet
In this work, a shifted wavelet packet (SWP) library, containing all the time shifted wavelet packet bases, is deened. A corresponding shift-invariant wavelet packet decomposition (SIWPD) search algorithm for a \best basis" is introduced. The search algorithm is representable by a binary tree, in which a node symbolizes an appropriate subspace of the original signal. We prove that the resultant...
متن کاملFrequency-Shift-Invariant Orthonormal Wavelet Packet Representations
It is commonly known that wavelet expansions are very sensitive to translation of an input signal due to their dyadic structure. Without proper time alignment of the signal to the decomposition basis vectors, a compact expansion may be unattainable. Recently, work has been done to combat translation sensitivity by determining the best translation-invariant expansion of a signal with respect to ...
متن کاملTranslation-invariant denoising using the minimum description length criterion
A translation-invariant denoising method based on the minimum description length (MDL) criterion and treestructured best-basis algorithms is presented. A collection of signal models is generated using an extended library of orthonormal wavelet-packet bases, and an additive cost function, approximately representing the MDL principle, is derived. We show that the minimum description length of the...
متن کامل