HIGHER-DENSITY DUAL TREE DISCRETE WAVELET TRANSFORM

This paper introduces the higher-density dual-tree (HDDT) discrete wavelet transform (DWT). A new MRA is introduced to describe higher-density DWT and used to obtain the sufficient condition for the HDDT Hilbert transform pair. In designing HDDT filters we use the extended common-factor method which not only includes the common-factor method but also provides exact linear phase bi-frame filters. Both HDDT tight frame and bi-frame (anti)symmetric filter design methods are given. At last, the results of denoising experiments by our newly designed HDDT filters in this paper prove the effectiveness of higher-density dual-tree DWT in the application of image processing.

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A Study on Pre-Filter Design for Improving Accuracy in Heart Rate Estimation from Backside Using Discrete Wavelet Transform with mm-Wave Radar

IEICE Communications Express ◽

10.1587/comex.2021xbl0160 ◽

2021 ◽

Author(s):

Ryosuke Koyanaka ◽

Shunsuke Sato ◽

Yaokun Hu ◽

Takeshi Toda

Keyword(s):

Heart Rate ◽

Wavelet Transform ◽

Discrete Wavelet Transform ◽

Filter Design ◽

Discrete Wavelet ◽

Rate Estimation ◽

Wave Radar ◽

Improving Accuracy ◽

Heart Rate Estimation

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CONTENT BASED IMAGE RETRIEVAL USING DISCRETE WAVELET TRANSFORM

International Journal of Pattern Recognition and Artificial Intelligence ◽

10.1142/s0218001404003046 ◽

2004 ◽

Vol 18 (01) ◽

pp. 19-32 ◽

Cited By ~ 3

Author(s):

SAEID BELKASIM ◽

XIANYU HONG ◽

O. BASIR

Keyword(s):

Wavelet Transform ◽

Image Retrieval ◽

Discrete Wavelet Transform ◽

Retrieval System ◽

Industrial Applications ◽

Discrete Wavelet ◽

Retrieval Process ◽

System A ◽

Image Transforms ◽

The Common

Image retrieval plays an important role in a broad spectrum of applications. Contentbased retrieval (CBR) is one of the popular choices in many biomedical and industrial applications. Discrete image transforms have been widely studied and suggested for many image retrieval applications. The Discrete Wavelet Transform (DWT) is one of the most popular transforms recently applied to many image processing applications. The Daubechies wavelet can be used to form the basis for extracting features in retrieving images based on the description of a particular object within the scene. This wavelet is widely used for image compression. In this paper we highlight the common features between compression and retrieval. Several examples are used to test the DWT retrieval system. A comparison between DWT and Discrete Cosine Transform (DCT) is also made. The retrieval system using DWT requires preprocessing and normalization of images, which might slow down the retrieval process. The accuracy of the retrieval using DWT has been significantly improved by incorporating efficient K-Neighbor Nearest Distance (KNND) measure in our system.

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A New Variable-Band Filter Design Method for the Discrete Wavelet Transform

2012 Ninth International Conference on Information Technology - New Generations ◽

10.1109/itng.2012.130 ◽

2012 ◽

Author(s):

Zhong Zhang ◽

Hiroshi Toda ◽

Takashi Imamura ◽

Tetsuo Miyake

Keyword(s):

Wavelet Transform ◽

Discrete Wavelet Transform ◽

Filter Design ◽

Design Method ◽

Discrete Wavelet ◽

Band Filter ◽

Filter Design Method

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Nonsubsampled higher-density discrete wavelet transform: Filter design and application in image contrast enhancement

2009 16th IEEE International Conference on Image Processing (ICIP) ◽

10.1109/icip.2009.5414406 ◽

2009 ◽

Cited By ~ 1

Author(s):

Arash Vosoughi ◽

Mohammad B. Shamsollahi ◽

Azadeh Vosoughi

Keyword(s):

Wavelet Transform ◽

Discrete Wavelet Transform ◽

Contrast Enhancement ◽

Filter Design ◽

Image Contrast ◽

Discrete Wavelet ◽

Image Contrast Enhancement ◽

Design And Application

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The Detection of Voltage Flicker Based on Complex Wavelets

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.48-49.1231 ◽

2011 ◽

Vol 48-49 ◽

pp. 1231-1234

Author(s):

Rui Zhang ◽

Gu Quan Liu ◽

Li Yong Zhang ◽

Xu Hui Zhang

Keyword(s):

Wavelet Transform ◽

Discrete Wavelet Transform ◽

Initial Time ◽

Discrete Wavelet ◽

Linear Phase ◽

Wavelet Bases ◽

Compactly Supported ◽

Phase Complex ◽

Complex Wavelet ◽

Voltage Flicker

The discrete wavelet transform based on the orthogonal wavelet bases has the disadvantage of shift-variant. In this paper, using the compactly supported dyadic orthogonal real-valued wavelet bases to construct the compactly supported dyadic orthogonal linear phase complex wavelet (LCW) bases in terms of alternately lifting scheme. Linear phase complex wavelet can separate the envelope of the flicker signal. The core of the method is a pair of Hilbert transform including the flicker signal in wavelet field is come into being, i.e. a pair of quadrature components with the same amplitude and the same frequency can be used to realize the demodulation of an amplitude modulated voltage flicker signal. Simulation experiments show the method proposed has the characteristic of shift-invariant comparing with the traditional discrete wavelet transform, result of separating envelope of the flicker signal is independent of initial time recording signal.

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