•Communication in watermarking is the host signal, with
the embedded data providing copyright protection.
•The existence of a watermark is often declared openly.
•Any attempt to remove or invalidate the embedded
content renders the host useless.
•Doesn’t conceal the communication.
•Scrambles the data to prevent eavesdroppers
understanding the content.
•Cryptography involves various methods and
•May be considered complementary and orthogonal
Once the presence of hidden information is revealed or even
suspected, the purpose of steganography is defeated.
4. 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.
This can be achieve by concealing the
existence of information within seemingly
harmless carriers or cover.
Carrier: text, image, video, audio, pdf etc.
5. Masking and Filtering: Is where information is hidden inside of a
image using digital watermarks that include information such
as copyright, ownership, or licenses. The purpose is different
from traditional steganography since it is adding an attribute to
the cover image thus extending the amount of information
Algorithms and Transformations: This technique hides data in
mathematical functions that are often used in compression
algorithms. The idea of this method is to hide the secret
message in the data bits in the least significant coefficients.
6. Least Significant Bit Insertion: The most common
and popular method of modern day steganography
is to make use of the LSB of a picture’s pixel
information. Thus the overall image distortion is kept
to a minimum while the message is spaced out over
the pixels in the images. This technique works best
when the image file is larger then the message file
and if the image is grayscale.
7. fE: steganographic function "embedding"
fE-1: steganographic function "extracting"
cover: cover data in which emb will be hidden
emb: message to be hidden
key: parameter of fE
stego: cover data with the hidden message
A novel design
9. A novel design
10. Security of the hidden communication
size of the payload
Robustness against malicious and
11. The detection of steganographically encoded packages
is called Steganalysis.
Visual Analysis tries to reveal the presence of secret
communication through inspection, either with the naked
eye or with the assistance of a computer.
Statistical (Algorithmic) Analysis reveals tiny
alterations in an image's statistical behavior caused by
The nominally universal methods developed to detect embedded
stego-data are generally less effective than the steganalytic methods
aimed at specific types of embedding.
Input: Cover_Image, Secret_Message, Secret_Key;
Transfer Secret_Message into Text_File;
Convert Zip_Text_File to Binary_Codes;
Convert Secret_Key into Binary_Codes;
Set BitsPerUnit to Zero;
Encode Message to Binary_Codes;
Add by 2 unit for bitsPerUnit;
Input: Stego_Image, Secret_Key;
Shift by 2 unit for bitsPerUnit;
Convert Binary_Codes to Text_File;
14. Stego image C
Multi Layer Dteganography
15. Now we can use This file for any
We can use it as network or one
We can rename also that will not
affect our data.
By visualization we can not get to
know that this file have some hidden
Password also required for