Steganography Final

8/3/2019 Steganography Final

http://slidepdf.com/reader/full/steganography-final 1/35

Steganography



AgendaWhat is Steganography?

Steganography Techniques.

Hierarchy.

Steganography VS Cryptography.Data hiding VS watermarking.

What is Steganalysis?

Categorizes of Steganalysis.Applications.



Agenda

What is Steganography? Steganography Techniques.

Hierarchy.



Categorizes of Steganalysis.

Applications.



What is Steganography ??

It is a Greek word.

Steganós (Stegano) Covered orprotected

Graphei (Graphy) writing

Stegano - Graphy Covered Writing.



What is Steganography ??

Practice of hiding information within

other information

Is the art and science of writing hidden

messages in such a way that no one, apart

from the sender and intended recipient,

suspects the existence of the message.





Hierarchy.




Applications.



Physical Steganography Past

Digital Steganography

Network Steganography

Audio Steganography

E-Text Steganography

Steganography techniques

Current

http://en.wikipedia.org/wiki/Steganography












Physical Steganography

The first recorded uses of Steganographycan be traced back to 440 BC.

Wax tablets.

Messenger's body.(drawbacks)

Secret ink.

Text messages.



Physical Steganography cont’d text Steganography

News Eight Weather: Tonight increasing

snow. Unexpected precipitation Smothers

Eastern t owns. Be extremely cautious and

use snow t ires especially heading east. Thehighways are k nowingly slippery. Highway

evacuation is suspected. Police report

emergency situations in downtown ending

near Tuesday

First letter of each word yields: Newt is

upset because he thinks he is President



Modern Steganography entered theworld in 1985.

The boom of Steganography coincideswith the appearance of the Internet.

Images , videos, etc.

Digital Steganography



Image of a tree with a steganographically hiddenimage. The hidden image is revealed by removing allbut the two least significant bits of each color

component and a subsequent normalization.

Digital Steganography cont’d





http://slidepdf.com/reader/full/steganography-final 13/35concealing

Why LSB ???




Why LSB????

10000001

LSB MSB

(10000001)2

= (129)10

(10000000)2 = (128)10

00000001

10000000

(00000001)2 = (1)10


http://slidepdf.com/reader/full/steganography-final 15/35Revealing




Network Steganography

Is a part of information hiding focused on modernnetworks and is a method of hiding secret data inusers' normal data transmissions, ideally, so it

cannot be detected by third parties.

EX: LACK ( Lost Audio Packets Steganography).



Network Steganography cont’d

LACK



Audio Steganography

Audio Steganography requires a text oraudio secret message to be embeddedwithin a cover audio message. Due toavailability of redundancy, the cover audiomessage before Steganography and thestego message after Steganographyremains the same.

Methods: LSB coding, Parity coding,Phase coding, Spread spectrum, Echohiding.



Audio Steganography

cont’d



Audio Steganography cont’d

LSB coding



text Steganography is considered to bethe most difficult kind of Steganographydue to the lack of redundancy in text as

compared to image or audio. However, itrequires less memory and provides forsimpler communication.

E-Text Steganography





Hierarchy.




Applications.



Hierarchy

Secret writing

Protection against detection

(data hiding)

Protection against removal

(document marking)

Watermarking

Fingerprinting

Steganography Cryptography





Hierarchy.




Applications.



Steganography VS Cryptography

Steganography Cryptography

•The message may not be difficult to

decode

•Most people would not detect the

presence of the message.

•Cryptography is hiding the content

of the message, but not the

existence of the message.

•one cannot decode the message

without knowing the proper key.•one can tell that a message has

been encrypted.



Why Steganography?

Encrypted messages are obvious ,usingSteganography we can hide them in other

innocuous looking objects so that their very

presence is not revealed.

Thus, Steganography can be a feasible

alter- native in countries where usage of encryption is illegal (China, Russia, Iran,

Iraq ,...).





Hierarchy.




Applications.



Data hiding VS Watermarking

Steganography (data hiding) Watermarking

Adding a hidden message to an image or other

media file.

Similar to encrypting a document, but instead

of running it through a cipher, the document is

broken up and stored in unused, or

unnoticeable, bits within the overall image.

Similar to steganography BUT

has a completely different purpose.

Placing a watermark in an image or other media

file serves to identify the artist or author of the

work. So, it isn’t for the purpose of hiding data.

Watermarking is used to protect the copyright

of the original owner, to make their claim

stronger, should the image be used without

permission by someone else.

So, the main goal of Steganography is to hide a

message m in some audio or video (cover) data

d, to obtain new data d', practicallyindistinguishable from d, by people, in such a

way that an eavesdropper cannot detect the

presence of m in d'.

So, the main goal of watermarking is to hide a

message m in some audio or video (cover) data

d, to obtain new data d', practicallyindistinguishable from d, by people, in such a

way that an eavesdropper cannot remove or

replace m in d‘.





Hierarchy.




Applications.



Steganalysis

What is Steganalysis ?

Steganalysis is the discovery of theexistence of hidden information; therefore,

like cryptography and cryptanalysis.

The goal: is to discover hiddeninformation and to break the security ofits carriers ( the files which have hiddeninformation inside of them).





Hierarchy.



Categorizes of Steganalysis.Applications.



Steganalysis algorithms can becategorized as:

Targeted Steganalysis :○ is one that is designed to detect stego Works that are

created by one or more particular steganographic methods. This provides a powerful clue with which to choose the feature representation.

Blind Steganalysis:○ If the method of detection is independent of the

Steganography method used.

the knowledge of the steganographic algorithm used.

It depends on





Hierarchy.




Applications.



Applications

1. Access control system for digital

content distribution. Publishing digital contents on the web and

limiting the controlling the access of thosecontents.

2. Usage in modern printers. Barely visible tiny yellow dots are added to each

page encoded printer serial numbers, date and

time stamps.



References http://www.datahide.com/BPCSe/applications-e.html

http://en.wikipedia.org/wiki/Steganography http://stegano.net/workshop/

http://arxivblog.com/?m=200811

http://stegano.net/tutorial.html

http://www.snotmonkey.com/work/school/405/methods.html#echo

http://mynetworksecurity.files.wordpress.com/2010/06/audio-steg.png

http://wajdyessam.sudancs.com/?p=159

http://www.datahide.com/BPCSe/applications-e.html

http://en.wikipedia.org/wiki/Steganography#Applications

Web-based Multimedia Steganography System – Paper. Digital Watermarking and Steganography – Second Edition



http://stegano.net/workshop/



http://www.snotmonkey.com/work/school/405/methods.html




























http://stegano.net/workshop/





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