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Evolution and algorithms of cryptography, steganography and watermarking.
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Cryptography & Steganography with
Water-Marking
Garima KulshreshthaAnushree
Bose MCA III SEM
Evolution
Watermarking
Cryptography
Steganography
CryptographyCryptography derived its name from a Greek word called “Kryptos” which means “Hidden Secrets”.
Cryptography is the practice and study of hiding information. It is the Art or Science of converting a plain text into a data which can’t be understood and again retransforming that message into its original form.
It provides Confidentiality, Integrity, Accuracy.
Symmetric Cryptography
Asymmetric Cryptography
SteganographyGreek Words : STEGANOS – “Covered”GRAPHIA – “Writing”
Steganography is the art and science of writing hidden messages in such a way that no one apart from the intended recipient knows of the existence of the message.
Stegosaurus: a covered lizard
Types of Steganography
Text
audio
image
video
protocol
LSB - Example
A sample raster data for 3 pixels (9 bytes) may be:
Inserting the binaryvalue for
A (10000001)
changes 4 bits
00100111 11101000 1100100000100110 11001000 1110100011001001 00100111 11101011
00100111 11101001 1100100000100111 11001000 1110100111001000 00100111 11101011
Image steganography algorithm
LSB - Uses
Storing passwords and/or other confidential information
Covert communication of sensitive data
Speculated uses in terrorist activities Being widely used to hide and/or
transfer illegal content
Watermarking
A watermark is a recognizable image or
pattern in paper that appears as various
shades of lightness/darkness when viewed
by transmitted light (or when viewed by
reflected light, a top a dark background),
caused by thickness variations in the
paper.
Digital Watermarking
A digital watermark is a digital signal or
pattern inserted into a digital document such
as text, graphics or multimedia, and carries
information unique to the copyright owner, the
creator of the document or the authorized
consumer.
VISIBLE WATERMARKING
INVISIBLE WATERMARKING
Digital Watermarking Process
EXAMPLE OF INVISIBLE WATERMARKING
EXAMPLE OF VISIBLE WATERMARKING
+ =
UV Watermarking
IIIIE-Book
INTERNET RADIO
INTERNET TV
INTERNET NEWSPAPER
INTERNET MAGZINE
EDUCATION MATERIAL
DOCUMENTS
CERTIFICATES
AUDIO
TEXT
IMAGE
VIDEO
GRAPHICS
WATERMARKING TECHNOLOGY
APPLICATION FIELD FOR WATERMARKING
Watermarking Vs. Steganography
Goal of Steganography Intruder Cannot detect message Primarily 1:1 communication
Goal of Watermarking Intruder cannot remove or replace
the message Primarily 1: many communication
Cryptography vs. Steganography
Cryptography: although encypted and unreadable, the existence of data is not hidden WHEREAS
Steganography: no knowledge of the existence of the data
REFERENCES
http://www.garykessler.net/library/steganography.html
http://www.fbi.gov/about-us/lab/forensic-sciencecommunications/fsc/july2004/research/2004_03_research01.htm
http://stegano.net/tutorial/steg-history.html
http://www.strangehorizons.com/2001/20011008/steganography.shtml
QUERIES ?
“For every lock there is a Key…
It is better to KEEP SAFE YOUR LOCK
THAN THE KEY”