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Inverse polynomial reconstruction method in DCT domain

Hamid Dadkhahi, Atanas Gotchev, Karen Egiazarian
2012 EURASIP Journal on Advances in Signal Processing  
To leverage the sparse representation provided by the DCT, in this article, we derive a framework for the inverse polynomial reconstruction in the DCT expansion.  ...  Furthermore, automatic methods based on minimum description length principle and cross-validation are devised to select the polynomial orders, as a requirement of the inverse polynomial reconstruction  ...  As a result, a new de-noising algorithm for piecewise smooth signals using inverse method in the DCT domain is presented.  ... 
doi:10.1186/1687-6180-2012-133 fatcat:34fxhn4eznel5jcamd6tv4rvci

An Improved Channel Estimation Method in OFDM System

Shun Xian Li
2013 Applied Mechanics and Materials  
compare some BEM models in inverse methodsto find out the best ones in certain conditions.  ...  the channel taps by the pilot information.We then estimate the BEM coefficients of the channel taps from their respective Fourier coefficients using a recently developed inverse reconstruction method.We  ...  In Section III, we introduce the inverse methods [X15] [X16] and DCT-BEM, P-BEM, DPSS-BEM.  ... 
doi:10.4028/ fatcat:l6nj2xbxabgjfgfykjgu7kfz2i

Fast downscaled inverses for images compressed with M-channel lapped transforms

R.L. de Queiroz, R. Eschbach
1997 IEEE Transactions on Image Processing  
Full decompression and rescaling in space domain is a very expensive method.  ...  In this fashion, fewer transform coefficients are used and the synthesis process is simplified. We studied the design of fast inverses, for a given forward transform.  ...  The reconstruction of the pixels is given by (29) Resizing in the DCT domain has been studied before [15] , [16] .  ... 
doi:10.1109/83.585231 pmid:18282974 fatcat:5shxlec5wrh5tjlsyp7a2ifdma

Transform-domain sparsity regularization for inverse problems in geosciences

Behnam Jafarpour, Vivek K. Goyal, Dennis B. McLaughlin, William T. Freeman
2009 Geophysics  
We use a discrete cosine transform ͑DCT͒ to obtain sparse representations of fields with distinct geologic features, such as channels or geologic formations in vertical cross section.  ...  Lowfrequency DCT basis elements provide an effectively reduced subspace in which the sparse solution is searched. The low-dimensional subspace is not fixed, but rather adapts to the data.  ...  Reconstruction results for the Burbank field porosity data using ͑a͒ the spline methods of Sandwell ͑1987͒, ͑b͒ geostatistical kriging, ͑c͒ l 1 -norm regularization in a low frequency DCT domain ͑LMN͒,  ... 
doi:10.1190/1.3157250 fatcat:xgieqxnp75fvnfspqhrhyc53oa

An efficient 2×2 Tchebichef moments for mobile image compression

Ferda Ernawan, Edi Noersasongko, Nur Azman Abu
2011 2011 International Symposium on Intelligent Signal Processing and Communications Systems (ISPACS)  
In the previous research, larger sub-block discrete Tchebichef moments have been used extensively for image compression.  ...  DCT is used to transform each pixel in the 8x8 block into frequency domain.  ...  The Tchebichef Moments Transform (TMT) is a method based on discrete Tchebichef polynomials [4] .  ... 
doi:10.1109/ispacs.2011.6146066 dblp:conf/ispacs/ErnawanNA11 fatcat:bukqvlhsfndzjlei7ndytel5r4

ASPL-APBT Algorithm for Block Compressed Sensing Image Reconstruction

Aiping Yang, Gai Li, Zhengxing Hou, Yuqing He
2014 Journal of Communications  
Experimental results demonstrate that the proposed algorithm outperforms the method of using DCT sparsifying coupled with common SPL iteration not only in the aspect of PSNR, but in terms of the reconstruction  ...  In recent years SPL based methods Manuscript  ...  Our contribution lies in that we cast the reconstruction in the all phase biorthogonal transform (APBT) domain [14] , [15] in which the signal has been shown to be sparser than in DCT domain.  ... 
doi:10.12720/jcm.9.4.371-378 fatcat:7efdmoqewrf63ascbrnpiyhypy

Discrete Fractional COSHAD Transform and Its Application

Hongqing Zhu, Zhiguo Gui, Yu Zhu, Zhihua Chen
2014 Mathematical Problems in Engineering  
This paper also develops an inverse polynomial reconstruction method (IPRM) in the discrete COSHAD/FrCOSHAD domains.  ...  In recent years, there has been a renewed interest in finding methods to construct orthogonal transforms.  ...  To solve this problem, this study follows the main description of the inverse polynomial reconstruction method (IPRM) for the continuous Fourier series expansion [14] [15] [16] and derives a mathematics  ... 
doi:10.1155/2014/567414 fatcat:ytk7zwcqnzaj7idqnt7r4zfbfa

Shape-adaptive DCT for denoising and image reconstruction

Alessandro Foi, Kostadin Dabov, Vladimir Katkovnik, Karen Egiazarian, Edward R. Dougherty, Jaakko T. Astola, Karen O. Egiazarian, Nasser M. Nasrabadi, Syed A. Rizvi
2006 Image Processing: Algorithms and Systems, Neural Networks, and Machine Learning  
The thresholded or modified SA-DCT coe cients are used to reconstruct a local estimate of the signal within the adaptive-shape support.  ...  We use the SA-DCT in conjunction with the directional LPA-ICI technique, which defines the shape of the transform's support in a pointwise adaptive manner.  ...  Significant improvement of this approach has been mean subtraction SA-DCT hard-thresholding inverse SA-DCT mean addition Figure 2 . Hard-thresholding in SA-DCT domain.  ... 
doi:10.1117/12.642839 fatcat:vpv7brqesrfxlocea23lpl7rzy

Reduced memory, low complexity embedded image compression algorithm using hierarchical listless discrete Tchebichef transform

Ranjan Kumar Senapati, Kamala Kanta Mahapatra, Umesh C. Pati
2014 IET Image Processing  
Abstract─ The Discrete Tchebichef Transform (DTT) based on orthogonal Tchebichef polynomials can be an alternative to Discrete Cosine Transform (DCT) for JPEG image compression standard.  ...  Through extensive simulation, image reconstruction accuracy (Peak Signal to Noise Ratio) and the number of bits required to encode the coefficients for both DCT and DTT is verified.  ...  Equation (1) defines the image transform τ where u and v represents the frequencies in the transform domain, f is the image being transformed, ' f is the inverse transform and ) , , , ( v u y  ... 
doi:10.1049/iet-ipr.2012.0295 fatcat:7jqc3q2jijaavexgegqroimk7q

ECG data compression by modeling

B Madhukar, I S Murthy
1992 Proceedings. Symposium on Computer Applications in Medical Care  
The method is based on Parametric modeling of the Discrete Cosine Transformed ECG signal.  ...  Improved high frequency reconstruction is achieved by separately modeling the low and the high frequency regions of the transformed signal.  ...  ,N-1 is the DCT of the input sequence s(n). Similarly the inverse DCT of S(k) can be computed to get back s(n).  ... 
pmid:1482940 pmcid:PMC2248130 fatcat:qwwwhhlkxbei7o4q2htrczuede

Spectrum analysis of speech recognition via discrete Tchebichef transform

Ferda Ernawan, Nur Azman Abu, Nanna Suryana
2011 International Conference on Graphic and Image Processing (ICGIP 2011)  
This paper proposes an approach based on discrete orthonormal Tchebichef polynomials to analyze a vowel and a consonant in spectral frequency for speech recognition.  ...  It carries strong potential in the near future as computing power grows. Spectrum analysis is an elementary operation in speech recognition.  ...  The inverse DTT is given in the following equation: , (12) 0, 1, … , 1, The first few discrete orthonormal Tchebichef polynomials are shown in Fig. 1 .  ... 
doi:10.1117/12.913491 fatcat:xizwjmgjvvhjfnaebvuelvi4ia

A Fast Block-Pruned 4x4 DTT Algorithm for Image Compression

Hassan I. Saleh
2009 Journal of clean energy technologies  
The Discrete Tchebichef transform (DTT) is a linear orthonormal version of the orthogonal Tchebichef polynomials, which is recently used in image analysis and compression.  ...  Furthermore, the experimental results show that the DTT is a good alternative for the Discrete Cosine Transform (DCT) in image compression especially for artificial diagrams images.  ...  A direct 2-D DCT method based on polynomial transform techniques was proposed in [1] . Another direct method is a matrix factorization algorithm of the 2-D DCT matrix [2] .  ... 
doi:10.7763/ijcte.2009.v1.41 fatcat:y2wgv2iadbh3xpvkhr5bbfjaqy

Image Restoration Using Two Statistical Modeling Methods

2016 International Journal of Science and Research (IJSR)  
In this paper various image deblurring methods are discussed which are used to remove blur from the images.  ...  perform inverse operation of it.  ...  The SA-DCT algorithm is used to image filtering. The SA-DCT is used with the Anisotropic Local Polynomial Approximation-Intersection technique.  ... 
doi:10.21275/v5i4.nov162499 fatcat:uwtjwpehdndbzjzgcjitw6ycve

Boundary-artifact-free phase retrieval with the transport of intensity equation: fast solution with use of discrete cosine transform

Chao Zuo, Qian Chen, Anand Asundi
2014 Optics Express  
This method promises to be an effective fast TIE solver for quantitative phase imaging applications.  ...  However, the boundary conditions are difficult to obtain in practice. The fast Fourier transform (FFT) based TIE solutions are widely adopted for its speed and simplicity.  ...  data by inverse DCT can be obtained in the first N elements of the inverse DFT result.  ... 
doi:10.1364/oe.22.009220 pmid:24787811 fatcat:otgi4w6r2ze2rou4hwem3wjoxu

Evaluation of F10.7, Sunspot Number and Photon Flux Data for Ionosphere TEC Modeling and Prediction Using Machine Learning Techniques

Andres Gilberto Machado da Silva Benoit, Adriano Petry
2021 Atmosphere  
A qualitative evaluation using reconstructed TEC maps indicated that the 3rd degree polynomial regression also seems inadequate.  ...  Different multi-dimension regression models were considered in experiments, where each geographic location was independently evaluated using its DCT frequency components.  ...  The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.  ... 
doi:10.3390/atmos12091202 fatcat:l3tw67aeozhrxghygew2ghtru4
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