scholarly journals Application of a novel image moment computation in X‐ray and MRI image watermarking

2020 ◽  
Author(s):  
Manoj K. Singh ◽  
Sanoj Kumar ◽  
Musrrat Ali ◽  
Deepika Saini
Keyword(s):  
Image Watermarking ◽  
X Ray ◽  
Image Moment ◽  
Mri Image

Magnetic resonance imaging for aspirated peanut in the bronchus

1994 ◽  
Vol 108 (9) ◽  
pp. 804-805 ◽  
Author(s):  
Yasuo Hisa ◽  
Keigo Tatemoto ◽  
Kenji Dejima ◽  
Yasuyuki Nishiyama ◽  
Yukari Masuda ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Lipid Content ◽  
Main Bronchus ◽  
Resonance Imaging ◽  
High Fat ◽  
X Ray ◽  
High Lipid ◽  
The Right ◽  
Mri Image

AbstractPeanut inhalation in the right main bronchus of a 15-month-old boy was diagnosed using a T1-weighted image produced by magnetic reasonance imaging (MRI) because of the high fat content of the peanut. The T1-weighted MRI image may also be useful in diagnosing other kinds of aspirated nuts with high lipid content as well as peanuts. This method does not involve any X-ray exposure.

Geometric Distortions Correction Using Image Moment in Image Watermarking

2011 ◽  
pp. 101-134
Author(s):  
Zhang Li ◽  
Sam Kwong
Keyword(s):  
Image Watermarking ◽  
Extraction Process ◽  
Geometric Distortion ◽  
Discrete Wavelet ◽  
Geometric Distortions ◽  
Geometric Moments ◽  
Image Moment ◽  
The Moment ◽  
Distortion Parameters ◽  
Geometrical Attacks

This chapter presents a method for detecting and recovering geometrical attacks in digital watermarking by making use of geometric moments of the original images. Digital image watermarking has become a popular technique for authentication and copyright protection. However, many proposed image watermarking techniques are sensitive to geometric distortions, such as rotation, scaling, and translation. In this chapter, we propose a new way of making this estimation by using the geometric moments of original image. The moment information can be used as a private key of extraction process. This method can be used as a preprocess of the extraction watermarking process. We have embedded different watermarks into original images in different domains including discrete wavelet transform (DWT), discrete cosine transfrom (DCT), fast Fourier transform, and spatial domain. The experimental results show that our method has a good robustness to wide geometric distortion parameters ranges and it is robust to Stirmark attacks.

A FRT - SVD Based Blind Medical Watermarking Technique for Telemedicine Applications

2019 ◽  
Vol 11 (2) ◽  
pp. 13-33 ◽  
Author(s):  
Surekah Borra ◽  
Rohit Thanki
Keyword(s):  
Medical Image ◽  
Medical Images ◽  
Image Watermarking ◽  
Region Of Interest ◽  
Singular Value ◽  
Ridgelet Transform ◽  
X Ray ◽  
Simulation Results ◽  
The Individual ◽  
Value Decomposition

In this article, a blind and robust medical image watermarking technique based on Finite Ridgelet Transform (FRT) and Singular Value Decomposition (SVD) is proposed. A host medical image is first transformed into 16 × 16 non-overlapping blocks and then ridgelet transform is applied on the individual blocks to obtain sets of ridgelet coefficients. SVD is then applied on these sets, to obtain the corresponding U, S and V matrix. The watermark information is embedded into the host medical image by modification of the value of the significant elements of U matrix. This proposed technique is tested on various types of medical images such as X-ray and CT scan. The simulation results revealed that this technique provides better imperceptibility, with an average PSNR being 42.95 dB for all test medical images. This technique also overcomes the limitation of the existing technique which is applicable on only the Region of Interest (ROI) of the medical image.

Space and Time Distribution of Hard X-Ray Emission in a Loop at the Beginning of a Flare

1994 ◽  
Vol 144 ◽  
pp. 275-277
Author(s):  
M. Karlický ◽  
J. C. Hénoux
Keyword(s):  
Time Distribution ◽  
Electron Bombardment ◽  
Spatial Evolution ◽  
Superthermal Electrons ◽  
Flare Loop ◽  
X Ray ◽  
Superthermal Electron ◽  
Flare Loops ◽  
Chromospheric Evaporation ◽  
Temporal And Spatial

AbstractUsing a new ID hybrid model of the electron bombardment in flare loops, we study not only the evolution of densities, plasma velocities and temperatures in the loop, but also the temporal and spatial evolution of hard X-ray emission. In the present paper a continuous bombardment by electrons isotropically accelerated at the top of flare loop with a power-law injection distribution function is considered. The computations include the effects of the return-current that reduces significantly the depth of the chromospheric layer which is evaporated. The present modelling is made with superthermal electron parameters corresponding to the classical resistivity regime for an input energy flux of superthermal electrons of 109erg cm−2s−1. It was found that due to the electron bombardment the two chromospheric evaporation waves are generated at both feet of the loop and they propagate up to the top, where they collide and cause temporary density and hard X-ray enhancements.

Some Problems in Understanding the Solar Corona

1994 ◽  
Vol 144 ◽  
pp. 1-9
Author(s):  
A. H. Gabriel
Keyword(s):  
Solar Corona ◽  
Solar Atmosphere ◽  
Theoretical Modelling ◽  
Total System ◽  
Major Advance ◽  
X Ray ◽  
Proper Perspective ◽  
Space Observations

The development of the physics of the solar atmosphere during the last 50 years has been greatly influenced by the increasing capability of observations made from space. Access to images and spectra of the hotter plasma in the UV, XUV and X-ray regions provided a major advance over the few coronal forbidden lines seen in the visible and enabled the cooler chromospheric and photospheric plasma to be seen in its proper perspective, as part of a total system. In this way space observations have stimulated new and important advances, not only in space but also in ground-based observations and theoretical modelling, so that today we find a well-balanced harmony between the three techniques.

White-Light Coronal Structures: Streamers and CMEs

1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner
Keyword(s):  
Emission Line ◽  
Electron Density ◽  
White Light ◽  
Coronal Mass Ejections ◽  
X Rays ◽  
Solar Cycles ◽  
Temperature Function ◽  
X Ray ◽  
Eclipse Observations ◽  
Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

Iron K-Line Emission from X-Ray Binaries

1988 ◽  
Vol 102 ◽  
pp. 47-50
Author(s):  
K. Masai ◽  
S. Hayakawa ◽  
F. Nagase
Keyword(s):  
Accretion Disk ◽  
Radiative Recombination ◽  
Characteristic Temperature ◽  
Line Emission ◽  
Ionization Front ◽  
Continuum Radiation ◽  
X Ray ◽  
Low Mass ◽  
X Ray Binaries

AbstractEmission mechanisms of the iron Kα-lines in X-ray binaries are discussed in relation with the characteristic temperature Txof continuum radiation thereof. The 6.7 keV line is ascribed to radiative recombination followed by cascades in a corona of ∼ 100 eV formed above the accretion disk. This mechanism is attained for Tx≲ 10 keV as observed for low mass X-ray binaries. The 6.4 keV line observed for binary X-ray pulsars with Tx> 10 keV is likely due to fluorescence outside the He II ionization front.

Diagnostics of Gold Laser Plasmas

1988 ◽  
Vol 102 ◽  
pp. 357-360
Author(s):  
J.C. Gauthier ◽  
J.P. Geindre ◽  
P. Monier ◽  
C. Chenais-Popovics ◽  
N. Tragin ◽  
...  
Keyword(s):  
Experimental Results ◽  
Pure Gold ◽  
Electronic Temperature ◽  
X Ray ◽  
Laser Plasmas ◽  
Collisional Radiative Model ◽  
Radiative Model

AbstractIn order to achieve a nickel-like X ray laser scheme we need a tool to determine the parameters which characterise the high-Z plasma. The aim of this work is to study gold laser plasmas and to compare experimental results to a collisional-radiative model which describes nickel-like ions. The electronic temperature and density are measured by the emission of an aluminium tracer. They are compared to the predictions of the nickel-like model for pure gold. The results show that the density and temperature can be estimated in a pure gold plasma.

Axial Observation of X-Ray Spectra from a Beam-Foil Source

1988 ◽  
Vol 102 ◽  
pp. 339-342
Author(s):  
J.M. Laming ◽  
J.D. Silver ◽  
R. Barnsley ◽  
J. Dunn ◽  
K.D. Evans ◽  
...  
Keyword(s):  
Spectral Resolution ◽  
Heavy Ion ◽  
Ion Beams ◽  
Beam Axis ◽  
Doppler Broadening ◽  
X Ray ◽  
Beam Foil

AbstractNew observations of x-ray spectra from foil-excited heavy ion beams are reported. By observing the target in a direction along the beam axis, an improvement in spectral resolution, δλ/λ, by about a factor of two is achieved, due to the reduced Doppler broadening in this geometry.

Observed and Theoretical Spectra in the 10–100Å Interval

1988 ◽  
Vol 102 ◽  
pp. 259-261
Author(s):  
W.A. Brown ◽  
M.E. Bruner ◽  
L.W. Acton
Keyword(s):  
Sounding Rocket ◽  
Full Spectrum ◽  
X Ray

AbstractThe soft x-ray spectra recorded in two sounding rocket flights in 1982 and 1985 are compared with with predicted spectra. The poster presents the processed densitometer trace of the full spectrum together with the new spectrum from the 1985 experiment. This note compares the intensities of the lines with predictions.

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