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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
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Proceedings ArticleDOI
23 May 2010
TL;DR: A general, unified approach to design and develop orthogonal wavelet packet bases according to a requirement is presented and two toy examples where families of wavelets which are maximally frequency selective and have the lowest cross correlation energy are developed.
Abstract: Wavelet Packet Modulation (WPM) is a novel multicarrier communication technique where information carrying symbols are placed on orthogonal wavelet packet bases. The WPM system is realized by a tree structure obtained by cascading a pair of half-band Quadrature Mirror Filter (QMF) duo. By altering the properties of these filters the transmission characteristics of the WPM system can be customized to a given design specification. In this article we present a general, unified approach to design and develop orthogonal wavelet packet bases according to a requirement. To this end, the design criterion and the wavelet constraints are first listed. The problem which is originally non-linear and non-convex in nature is then converted into a tractable convex optimization problem and finally solved using suitable Semi Definite Programming (SDP) tools. The proposed mechanism is demonstrated through two toy examples where families of wavelets which are i) maximally frequency selective and ii) have the lowest cross correlation energy, respectively, are developed.

4 citations

Journal ArticleDOI
TL;DR: An algorithm is proposed that blindly detects global rescaling operation using the statistical models computed based on quadrature mirror filter (QMF) decomposition to prove the validity of the algorithm under different interpolation schemes.
Abstract: High resolution digital cameras and state-of-the-art image editing software tools has given rise to large amount of manipulated images leaving no traces of being subjected to any manipulation. Passive or blind forgery detection algorithms are used in order to determine its authenticity. In this paper, an algorithm is proposed that blindly detects global rescaling operation using the statistical models computed based on quadrature mirror filter (QMF) decomposition. Fuzzy entropy measure is employed to choose the relevant features and to remove non-important features whereas artificial neural network classifier is used for forgery detection. Experimental results are presented on grayscale and G-component images of UCID database to prove the validity of the algorithm under different interpolation schemes. Results are provided for the detection of rescaled images with JPEG compression, arbitrary cropping and white Gaussian noise addition. Further, results are shown using USC-SIPI database to prove the robustn...

4 citations

Proceedings ArticleDOI
17 May 2004
TL;DR: A new technique for designing pairs of filter banks whose corresponding wavelet functions are approximate Hilbert transforms of each other, which yields biorthogonal wavelets with exact symmetry.
Abstract: This paper presents a new technique for designing pairs of filter banks whose corresponding wavelet functions are approximate Hilbert transforms of each other. The filters have exact linear phase which yields biorthogonal wavelets with exact symmetry. The technique is based on matching the frequency response of a given odd-length filter bank with an even-length filter bank. The class of EBFB (even-length Bernstein filter bank) is utilized in the matching design. The EBFB has perfect reconstruction and vanishing moments properties structurally imposed and this simplifies the design process. The design is achieved through a non-iterative least squares method.

4 citations

Proceedings ArticleDOI
01 Oct 2008
TL;DR: The proposed technique protects the data quality by applying Linear Predictive Coding-10 and achieves the low bit rate by applying Quadrature Mirror Filter in an attempt to improve the dataquality at low bit rates as well as fast transmission of data.
Abstract: High data quality at low bit rate is an essential goal that people want to achieve. It is necessary to transfer data at low bit rate so that the bandwidth of the medium can be utilized efficiently. In most of the speech coding techniques the goal of low bit rate transfer is achieved but the data quality is affected badly. The proposed technique is an attempt to improve the data quality at low bit rate as well as fast transmission of data. The proposed technique protects the data quality by applying Linear Predictive Coding-10 and achieves the low bit rate by applying Quadrature Mirror Filter. A comprehensive analysis is on the basis of given parameters as size, compression time, Signal to Noise Ratio, power, energy, power in air, energy in air, mean, standard deviation and intensity.

4 citations

Book ChapterDOI
19 Dec 2011
TL;DR: This paper introduces a novel method named DEGL (Differential Evolution with global and local neighborhoods) regarding the design of two channel quadrature mirror filter with linear phase characteristics to optimize the values of the filter bank coefficients.
Abstract: This paper introduces a novel method named DEGL (Differential Evolution with global and local neighborhoods) regarding the design of two channel quadrature mirror filter with linear phase characteristics. To match the ideal system response characteristics, this improved variant of Differential Evolution technique is employed to optimize the values of the filter bank coefficients. The filter response is optimized in both pass band and stop band. The overall filter bank response consists of objective functions termed as reconstruction error, mean square error in pass band and mean square error in stop band. Effective designing can be performed if the objective function is properly minimized. The proposed algorithm can perform much better than the other existing design methods. Three different design examples are presented here for the illustrations of the benefits provided by the proposed algorithm.

4 citations

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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20231
20227
20214
20203
20197
201812