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Quadrature mirror filter

About: Quadrature mirror filter is a research topic. Over the lifetime, 955 publications have been published within this topic receiving 28900 citations.


Papers
More filters
Proceedings ArticleDOI
04 Dec 2000
TL;DR: In this article, canonical correlations and canonical angles are used to quantify the difference between subspaces spanned by two filter pairs, and the utility of this method as a data independent metric for filter comparison is shown.
Abstract: In previous work, hybrid wavelet packets were introduced as a generalization of wavelet packets in which the choice of quadrature mirror filter (QMF) is selected adaptively within the wavelet packet analysis. This was motivated by the observation that for certain classes of signals, the choice of appropriate QMF is not only signal dependent, but may be scale dependent as well. Best Basis selection was generalized to provide a means of optimizing the representation of a given signal. This method can be viewed as an adaptive partitioning of signal subspaces. In such a scheme it is important to determine a small number of QMFs which will provide some diversity in the partitioning of the subspaces. In the current work, canonical correlations and canonical angles are used to quantify the difference between subspaces spanned by two filter pairs. Preliminary results indicate the utility of this method as a data independent metric for filter comparison.
01 Jan 2008
TL;DR: In this article, the relationship between QMFB and QMHT was established for systems with perfect reconstruction for a given quadrature mirror filter bank and the filter specifications and the design procedure for the QM HT were investigated.
Abstract: Applying a /2 π frequency shift to the original quadrature mirror filter bank (QMFB), ( ) ( ) 0 0 z H z H z P - = . The related QMHT is obtained by substituting -jz z → into ( ) z P. This work establishes the relationship between QMFB and QMHT for systems with perfect reconstruction. For a given QMFB, filter specifications and the design procedure for the QMHT are investigated.
Journal Article
TL;DR: Simulation results presented in this paper how enhanced performance of this algorithm over the other existing algorithms.
Abstract: In this paper, a closed form method for designing two-channel linear phase Quadrature Mirror Filter (QMF) bank presented by Kumar et al. is examined and improved by exploiting different window functions for designing the prototype filter for QMF bank. In this method, the optimum pass-band edge frequency is determined via empirical formula instead of using single or multivariable optimisation technique for the given stop-band attenuation and roll-off factor (RF). This method reduces the overall computational time with minimum amplitude distortion to make suitable design of QMF bank for applications, which are carried out in real or quasi-real time. Simulation results presented in this paper how enhanced performance of this algorithm over the other existing algorithms.
Proceedings ArticleDOI
06 Apr 1995
TL;DR: In this paper, the authors introduce vector-valued multiresolution analysis and vectorvalued wavelets for vectorvalued signal spaces, which can be thought of as a family of unitary vector transforms.
Abstract: In this research, we introduce vector-valued multiresolution analysis and vector-valued wavelets for vector-valued signal spaces. We construct vector-valued wavelets by using paraunitary vector filter bank theory. In particular, we construct vector-valued Meyer wavelets that are band-limited. We classify and construct vector-valued wavelets with sampling property. As an application of vector-valued wavelets, multiwavelets can be constructed from vector-valued wavelets. We show that certain linear combinations of known scalar-valued wavelets may yield multiwavelets. We then present discrete vector wavelet transforms for discrete-time vector-valued (or blocked) signals, which can be thought of as a family of unitary vector transforms. In applications of vector wavelet transforms in two dimensional transform theory, the nonseparability can be easily handled.
Proceedings ArticleDOI
22 Aug 1999
TL;DR: Embedded zerotree wavelet (EZW) image coding is efficient and uses significance ordering for coefficients and can be arbitrarily terminated resulting in high compression ratios with satisfactory image quality.
Abstract: Embedded zerotree wavelet (EZW) image coding is efficient and uses significance ordering for coefficients. EZW encoding can be arbitrarily terminated resulting in high compression ratios with satisfactory image quality. Given a requested scale for an image section matched to the resolution of the viewer, when can the EZW encoding be terminated and how can a specified quality for the image representation be obtained? One can compute the effect from the aliasing of higher frequencies. The aliased signals are in the cut-off band of the analysis quadrature mirror filter. The more significant, and therefore earlier, EZW coefficients produce the majority of the alias error. So the encoding can be terminated once a specified residue alias error is reached. Then the update of the full precision of the relevant discrete wavelet transform coefficients for that scale are required to provide image representation on the viewer with low or no distortion.
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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20231
20227
20214
20203
20197
201812