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Steganalysis

Zeros hiding detection

In order to find data hiding with our zeros hidden method, we first analyzed the histogram of the DCTcoefficients of an uncompressed image, compressed image without data, and compressed image with hidden data. The histogram of theDCT coefficients reveals the number of times each DCT coefficient value appears within the DCT matrix. From the analysis of anuncompressed image (Figure 1), the histogram has a smooth curve. In the histogram of compressed image (Figure 2), values before thethreshold are dropped. Therefore, those values dropped to zero in the histogram. The histogram of compressed image with data (Figure3) shows a similar shape to an uncompressed image. However, the values are much lower which makes sense since we are replacing thevalues that were originally going to be dropped with data. Therefore it is statically less likely to replace the dropped valuewith the same value.

Therefore, after analyzing the histogram of the different types of images, we did an analysis of the l2 norm inthe DCT matrix. If the analysis results in no power in the one valued DCT coefficients, it is a compressed image. This is due tothe fact that ones are the minimum value that can be dropped. If there is power in the ones, then the image is either uncompressedor contains hidden data. The key difference between the two is the magnitude of the power in the ones. Statistically, it is lesslikely that every dropped coefficient gets replaced with a one. Therefore, the magnitude of the power in the ones in an image withdata is lower than a compressed image. An image with hidden data will on average fall below a certain threshold. This threshold isdependent on the image size. Figure 4 shows the plots of the power without data, the power with data, and the threshold. Clearly, thepower without data is greater than the power with data. We found our detection program to have a 90% success rate but resulted in afalse-positive 12% of the time.

L2 norm equation

x 2 = n = 0 N - 1 | x n | 2 1 2 2 x n 0 N 1 x n 2 1 2

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Elec 301 projects fall 2005. OpenStax CNX. Sep 25, 2007 Download for free at http://cnx.org/content/col10380/1.3
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