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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
14 Oct 1996
TL;DR: The design trade-off and overall performance of a quadrature mirror filter pair, in combination with a 2D diagonal prefilter is explored and the ensuing problems of avoiding and compensating for aliasing within the subbands, as for the signal reconstruction process at the decoder are highlighted.
Abstract: This paper discusses the many and varied design considerations of a 2D digital subband filter bank implementation for orthogonal sampling structures, which enables the derivation of only two subbands rather than the usual four. In particular, the design trade-off and overall performance of a quadrature mirror filter pair, in combination with a 2D diagonal prefilter is explored and the ensuing problems of avoiding and compensating for aliasing within the subbands, as well as for the signal reconstruction process at the decoder are highlighted.

3 citations

Proceedings ArticleDOI
06 Sep 1989
TL;DR: In this article, a Max-Lloyd quantizer was incorporated into a quadrature mirror filter (QMF) splitting and reconstruction scheme for quantization in an image subband filter bank, and a mean-squared error calculation and a subjective evaluation of these coding errors on both monochrome and color images were conducted.
Abstract: Summary form only given. The errors due to quantization in an image subband filter bank have been analyzed by explicitly incorporating a model for a Max-Lloyd quantizer into a quadrature mirror filter (QMF) splitting and reconstruction scheme. The used quantizer model, known as the gain-plus-additive-noise model, consists of a signal part with less than unity gain and a random part that is uncorrelated with the input signal. Measurements show that this model accurately fits the data. Moreover, it enables such coding errors as aliasing, QMF design errors, signal errors, and random errors to be discriminated. A mean-squared error (MSE) calculation and a subjective evaluation of these coding errors on both monochrome and color images have shown that luminance errors are more dominant than chrominance errors, even when the chrominance signals only use 25% of the bits. Further, aliasing errors do occur in the case of quantization. They are not completely cancelled anymore by the QMFs. These errors, however, can be neglected for filter lengths of 16 taps or more. The signal error determines the sharpness of the reconstructed image, while the random error appears in flat areas but also round edges. >

3 citations

Proceedings ArticleDOI
01 Dec 2013
TL;DR: In this paper, a particle swarm optimization (PSO) technique was used to obtain the scaling function of a single note played by musical instruments using the waveform of a musical instrument.
Abstract: The waveform of a single note played by musical instruments has a repeating element, as it contains fundamental frequency and its harmonics. This waveform can be used as the scaling function for analysing the signals produced by that particular musical instrument, provided it satisfies the necessary and sufficient condition for a scaling function. In this paper, the filter coefficients corresponding to this scaling function is obtained using Particle Swarm Optimization(PSO) technique. For known wavelets, like Daubechies, the scaling function can be iteratively found from the filter coefficients. However, it is difficult to generate the filter coefficients from the wavelets without the knowledge of some characteristics of the scaling function or the wavelet. In this context, the PSO model which has been developed here gives very accurate values of the filter coefficients for any given scaling function. Further, ordinary PSO is modified for better optimization resulting in a new wavelet for music signals called as Sinith-Shikha-Murthy (SSM) wavelet. The working of the proposed models are verified using Daubechies wavelet. The filter coefficients corresponding to the signal generated by musical instruments flute and violin are also found. The regeneration of the scaling function iteratively using the obtained filter coefficients confirmed the results.

3 citations

Proceedings ArticleDOI
03 Nov 1996
TL;DR: In this article, a new type of perfect-reconstruction QMF system is proposed, which is based on half-band filters so that it has lower complexity and group delay than the known QMF systems, with comparable performance.
Abstract: A new type of perfect-reconstruction QMF system is proposed. The filter system is based on half-band filters so that it has lower complexity and group delay than the known QMF systems, with a comparable performance. It is shown that the new PR QMF system achieves zero phase distortion and zero amplitude distortion, in addition to producing alias-free outputs. A filter optimization technique is also proposed for its prototype low pass filter. For realization, its polyphase architecture is derived, which has a very simple structure.

3 citations

Proceedings ArticleDOI
25 Jul 2004
TL;DR: In this paper, the design of two channel linear phase quadrature mirror filter (QMF) banks is considered with constraints on the peaks of the reconstruction error and that of the subband filter ripple sizes.
Abstract: The design of two channel linear phase quadrature mirror filter (QMF) banks is considered with constraints on the peaks of the reconstruction error and that of the subband filter ripple sizes. We further considered the design specification without explicitly specified transition band for the subband filters. An iterative algorithm is proposed to design QMF banks that can incorporate with various design constraints. We have suggested the possible design tradeoff between transition band bandwidth and the ripple size of the subband subband filter and/or the reconstruction error. Various design examples are presented to illustrate the versatility of the digital QMF banks obtained by the proposed design method. The algorithm is proved to converge and was found to converge efficiently in all the simulations.

3 citations

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