نتایج جستجو برای: wavelet transforms

تعداد نتایج: 57594  

Journal: :Optical Engineering 1992

Watermarking is one of the best solutions for copyright protection and authentication of multimedia contents. In this paper a hybrid scheme is proposed using wavelet and shearlet transforms with singular value decomposition. For better security, Arnold map is used for encryption. Examining the results and comparing with other methods show that this hybrid proposed scheme with simultaneous utili...

2001
Michael D. Adams Rabab Ward

Studied are numerous issues associated with wavelet transforms in the JPEG-2000 Part-1 standard (i.e., ISO/IEC 15444-1). The dynamic range of wavelet transform coefficients and computational complexity of wavelet transforms are examined. Also, the effect of wavelet transforms on coding efficiency is investigated. The information presented herein may prove beneficial to those developing JPEG-200...

Journal: :Journal of Mathematical Analysis and Applications 1998

1998
Roger L. Claypoole Richard G. Baraniuk Robert D. Nowak

This paper develops two new adaptive wavelet transforms based on the lifting scheme. The lifting construction exploits a spatialdomain, prediction-error interpretation of the wavelet transform and provides a powerful framework for designing customized transforms. We use the lifting construction to adaptively tune a wavelet transform to a desired signal by optimizing data-based prediction error ...

Let  $varpi$ be a representation of the homogeneous space $G/H$, where $G$ be a locally compact group and  $H$ be a compact subgroup of $G$. For  an admissible wavelet $zeta$ for $varpi$  and $psi in L^p(G/H), 1leq p <infty$, we determine a class of bounded  compact operators  which are related to continuous wavelet transforms on homogeneous spaces and they are called localization operators.

Journal: :journal of medical signals and sensors 0

electrocardiogram (ecg) is one of the most common biological signals which plays a significant role in diagnosis of heart diseases. one of the most important parts of ecg signal processing is interpretation of qrs complex and obtaining its characteristics. r wave is one of the most important sections of this complex which has an essential role in diagnosis of heart rhythm irregularities and als...

2005
Jean-Luc Starck Yassir Moudden Pierrick Abrial Mai Nguyen

We present in this paper new multiscale transforms on the sphere, namely the isotropic undecimated wavelet transform, the pyramidal wavelet transform, the ridgelet transform and the curvelet transform. All of these transforms can be inverted i.e. we can exactly reconstruct the original data from its coefficients in either representation. Several applications are described. We show how these tra...

2013
Tanuja Sarode Prachi Natu

In this paper, image compression using orthogonal wavelet transforms of Walsh, Cosine, Haar, Kekre, Slant and Sine is studied. Wavelet transform of size N 2 xN 2 is generated using its corresponding orthogonal transform of size NxN. These wavelet transforms are applied on R, G, and B planes of 256x256x3 size colour images separately. In each transformed plane rows/columns are sorted in their de...

2007
Ivan W. Selesnick

transforms to compress digitally scanned fingerprints. NASA’s Mars rovers use them to compress images acquired by their 18 cameras. The new JPEG 2000 format is based on wavelet transforms; the smaller files allow one to store images using less memory and to transmit those images faster and more reliably. Researchers also use wavelet transforms to clean signals and images—that is, to reduce unwa...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید