This document presents a new image steganography technique called M16M (Mode 16 Method). It embeds secret messages into digital images in 3 steps: 1) selecting seed pixels, 2) choosing neighboring pixels, and 3) modifying pixel intensities according to the message bits. Modifying intensities slightly allows embedding large payloads without noticeable quality loss. Future directions may combine steganography with cryptography for stronger security or use it for digital watermarking applications. Steganography can enhance security for confidential documents and will likely be important for digital watermarking and copyright protection going forward.

1. Image Steganography Using
Mode 16 Method(M16M)
Presented By :
 Arko Kundu
4th
year CSE, UIT, BU
 Kaushik Chakrarborty
4th
year CSE, UIT, BU
 Sauvik Bhattacharyaa
Associate Professor(CSE), UIT, BU
Department of Computer Science and Technology
University Institute of Technology,
THE UNIVERSITY OF BURDWAN

2. What is STEGANOGRAPHY?
According to Wikipedia :
Steganography is the art and science of writing
hidden messages in such a way that no one apart from the sender and
intended recipient even realizes there is a hidden message.
The word comes from Greek steganos or “covered”
and graphie or “writing” meaning “covered or hidden writing”.
Two examples of how it appeared:
1.Demaratus sent a warning about a forthcoming attack to Greece by
writing it on a wooden panel and covering it in wax.
2.Another ancient example is that of Histiaeus encouraged
Aristagoras of Miletus to revolt against Persian king. He shaved the
head of his most trusted slave and tattooed a message on it. After
his hair had grown the message was hidden.

3. Real World Cases
Steganography is being used as a very powerful technique, even to Criminal
Organizations :
1.USA reported that bin Laden and others "are hiding maps
and photographs of terrorist targets and posting instructions for terrorist activities
on sports chat rooms , pornographic bulletin boards and other websites, U.S. and
foreign officials say.“
2. Hello Kitty images were used by Colombian Drug lord Juan Carlos Ramirez Abadia
to hide messages to his minions as Steganography vector. Abadia apparently picked
Hello Kitty ashis courier because his wife was a big fan of the Japanese icon -- she
had even decorated one of her rooms in a Brazilian house with Hello Kitty-themed
chairs, watches and wallpaper
The Hello Kitty Image which was
used as the Stego Image

4. The Modern Framework(The Prisoners Problem)
Here Alice and Bob are two Inmates who wish to communicate and Wendy
is the Warden and examines all the message passed between them.
Secret
Message
Secret
Message
Secret
Message
Secret
Message
Secret KeySecret Key
Message
Retrieval
Algorithm
Message
Retrieval
Algorithm
Suppress
Message
Suppress
Message
Stego
Message
Stego
Message
Embedding
Algorithm
Embedding
Algorithm
Cover
Message
Cover
Message
Secret KeySecret Key
Is
Stego
msg?
Is
Stego
msg?
ALICE WENDY BOB

5. Most simple properties of
general Steganography
All key properties for
Good Steganography
Characteristics Of Strong Steganography

6. What’s happening before
embedding ??

7. Seed Pixel Selection
Seed Pixel Generation for embedding message bits is
dependent on the intensity value of the previous pixel selected.
It includes a decision factor (dp) which is dependent on
intensity with a fixed way of calculating the next pixel.
x=x1+2+dp
y=y1+2+dp
(x,y)=new Pixel position
(x1,y1)=previous Pixel position
Intensity >80 &&
<=160
Intensity >160 &&
<=255
dp=1
dp=2
dp=3
Intensity <=80

8. An Example… (Seed Pixel Selection)
122 45 69 132 256 145 56 79 112 125
156 125 169 123 79 78 12 186 123 69
224 212 145 125 147 86 45 110 236 26
119 248 46 112 48 23 79 45 90 156
119 79 116 189 53 30 130 90 141 171
56 71 26 83 43 75 93 67 116 49
90 112 179 212 201 38 99 119 157 39
83 53 89 115 63 78 90 76 255 255
131 141 176 159 126 146 255 73 86 255

9. An Example
( Neighboring Pixel Selection )
112 48 23
189 53 30
83 43 75
i+1,j
i+1,j-1 i+1,j+1
i,j-1 i,j+1
i-1,j-1 i-1,j+1
i-1,j

10. Embedding Technique
The Summarized Algorithm is as follows :
1.Select a seed pixel.
2.Select the neighbouring pixels.
3.Find the intensity of the neighbouring pixels .Find out and store the
remainder after dividing the intensity by 16.
Let the remainder be R .
4.Subtract R from the intensity and hence the resultant is divisible by
16.
Cont………

11. 5. Now add different values to the resultant intensity according to the different
4 bit binary message to be embedded according to the table given below :-
MSG VALUE TO BE ADDED
0000 0
0001 1
0010 2
0011 3
0100 4
0101 5
0110 6
0111 7
1000 8
1001 9
1010 10
1011 11
1100 12
1101 13
1110 14
1111 15
6. The modified intensity is replaced in the original image matrix.
7. At the end we get the stego matrix embedded with the message.

12. Embedding Example
Message to be embedded = 0011

13.
The summarized Algorithm is as follows :
1.Select a seed pixel.
2.Select the neighbouring pixels.
3.Find the intensity of the neighbouring pixels and find out and store
the remainder after dividing it by 16. Let the remainder be R .
4. Now R represents the Decimal Value of the embedded message .
When converted to 4-bit binary format we get our resultant message at
the receiver’s end.
Extracting Technique

14. Extracting Example
Extracted Message = 0011

15. What the difference in picture
quality after embedding ?
Original Lena (Capacity=19684 characters) Stego Lena
PSNR (after embedding the 19684 characters) = 34.6516
PSNR (after embedding 1000 characters) = 47.3268
After Embedding
19684 Characters

16. What’s ahead in FUTURE……………. ??
 In today’s world, we often listen a popular term “Hacking”..
So, whatever be the technique will be developed in
future, degree of security related with that has to be kept in
mind. It is hoped that Dual Steganography, “Steganography
along with Cryptography “ may be used to achieve some
of the future solution for this above mentioned problem.
 In the near future, the most important use of steganographic
techniques will probably be lying in the field of “Digital
Watermarking”.
Can be used to enhance a country’s security system regarding
confidential documents.

17. Conclusion
The work dealt with the techniques for steganography as
related to gray scale image. A new and efficient
steganographic method for embedding secret messages
into images without producing any major changes has
been proposed. Although in this method it has been shown
that each four bit of the secret message has been mapped
in the pixels of the cover image, but this method can be
extended to map n no of bits also by considering more no
of features of the embedding pixels. This method also
capable of extracting the secret message without the cover
image. This approach can also be used in coloured images.

18. Questions …. ???

19. With Regards…..!!!
 Arko Kundu
 Kaushik Chakrarborty
 Sauvik Bhattacharyaa