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Page 1: Data Hiding using LSB Steganography technique - IJCTA · Data Hiding using LSB Steganography technique. ... Encryption, Decryption, ... Simplified DES (S-DES): The S-DES encryption

Data Hiding using LSB Steganography technique

Rituraj Rusia1, Munendra Kumar Mishra2, R. K. Tiwari3 1Ph.D.(CS) Research Scholar, MGCGVV, Chitrakoot (MP)

2 Vindhya Institute of Technology and Science (VITS), Satna (MP) 3Head of Dept. of Physics, Govt. M. S. Golvarkar New Science College, Rewa (MP)

1 [email protected] 2 [email protected]

3 [email protected]

Abstract

The applications accessing multimedia systems and

content over the Web have grown extremely in the

past few years. Furthermore, many end users can

easily use tools to synthesize and edit multimedia

information. Thus, security has become one of the

most significant problems for distributing new

information technology. It is necessary to protect

this information while communicated over insecure

channels. It is also important to determine where

and how such a multimedia file is confidential.

Thus, a need exists for developing technology that

will help protect the integrity of digital content and secure the intellectual property rights of owners.

Cryptography is a means to achieve this task.

In this paper, a secured package is implemented

and integrated under the hash function umbrella to

provide appropriate services for protecting

multimedia through communication channels. The

algorithm was tested with different cryptosystems

using multimedia files under windows environment

and it was proved that extracting any information

about the encrypted information is hard for any

eavesdropper with computational resources. In

addition, information security results with

experimental examples are discussed and finally

conclusion and remarks are presented.

KEYWORDS Cryptography, Steganography, Stego-image,

Data Hiding, Encryption, Decryption, Multimedia Information, Image Compression, Embedding, etc.

1. Introduction While in multimedia communications, the need

of confidentiality and privacy gains more and more

in importance, particularly in open networks like

the Internet. In this age of universal electronic

connectivity, of viruses and hackers, of electronic

eavesdropping and electronic fraud, there is indeed

a need to protect information from passing before curious eyes or, more importantly, from falling into

wrong hands. Thus, multimedia security is much to

consider in distributing digital information safety.

Cryptography is the study of mathematical

techniques related to aspects of information

security such as confidentiality, data integrity,

entity authentication, and data origin authentication

[1-3]. Cryptography scrambles a message so it

cannot be understood. Steganography hides the

message so it cannot be seen. A message in

ciphertext, for instance, might arouse suspicion on

the part of the recipient while an “invisible”

message created with steganographic methods will

not. Cryptography is probably finding its widest

use today (and perhaps its widest use in history) in

securing and validating information in many

applications. Secure sockets layer (SSL) and

transport layer security (TLS), used to encrypt

information exchanges conducted over the World

Wide Web. In the next section, a brief of how this

package is working and its stages are presented.

1.1. The State of the Art: This package works in a sequence (sometimes

these stags are optional). The two parties who are

in communication, usually called Alice, the Sender,

and Bob, the receiver will start to communicate.

The sender decides if the plaintext needs to be

compressed or not depending on its size. Then the

key, which will be used in the encryption process,

will be hashed using a hash technique and inserted

into the plaintext as a message authentication code

(MAC). This plaintext is encrypted using a

cryptosystem that is called Key-Based Security

Algorithm (KBSA) [4]. The compressed hashed

encrypted data is then embedded into an innocent

image “cover-image” after preprocessing it using a

steganographic algorithm producing stego-image.

Before this stego-image is transmitted through

communication channels to the other party, it is compressed using image compression. This

communication takes place in the presence of a

warden. The receiver by his role will do the

reverse operation to extract the original plaintext

after extracting it from the stego- image. The

relative entropy between the cover image and the

stego image is zero. A tractable objective measure

for this property is the (weighted) mean squared

error between the cover image and the stego image

(embedding distortion). The resulting stego and the

cover images should be indistinguishable by the

naked eye. In the next sections a description is

given of the package stages including

cryptographic algorithms, network security, hash

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function, steganographic algorithms, and

compression algorithm that are used to accomplish

the model. In this package more than 12

cryptosystems were implemented, 3 hash function

algorithms and 1 steganographic algorithm

gathered together into a library that might work

easily and is manipulated by the user to deal with

the multimedia plaintext.

1.2. Basic Concepts and Related Work: There are many aspects to security and many

applications. One essential aspect for secure

communications is that of cryptography. But it is

important to note that while cryptography is

necessary for secure communications, it is not by

itself sufficient. There are some specific security

requirements for cryptography, including

Authentication, Privacy /confidentiality, and

Integrity Non -repudiation. The three types of

algorithms are described:[18]

(i) Secret Key Cryptography (SKC): Uses a

single key for both encryption and decryption.

(ii) Public Key Cryptography (PKC): Uses one

key for encryption and another for decryption.

(iii) Hash Functions: Uses mathematical

transformation to irreversibly "encrypt"

information. Steganography is the other technique for secured

communication. It encompasses methods of

transmitting a secret message through innocuous

cover carriers in such a manner that the very

existence of the embedded messages is

undetectable. Information can be hidden in images,

audio, video, text, or some other digitally

representative code.

Steganography systems can be grouped by the

type of covers used (graphics, sound, text,

executable) or by the techniques used to modify the

covers

a) Substitution system.

b) Transform domain techniques.

c) Spread spectrum techniques.

d) Statistical method.

e) Distortion techniques. f) Cover generation methods.

Text steganography, Image steganography,

Audio steganography, video steganography, and

Protocol steganography. Some of the

steganography methods are

1. LSB

2. MASKING

3. FILTERING

4. TRANSFORM TECHNIQUE

The best known steganographic method that

works in the spatial domain is the LSB (Least

Significant Bit), which replaces the least significant

bits of pixels selected to hide the information. A

large number of commercial steganographic

programs use the Least Significant Bit embedding

(LSB) as the method of choice for message hiding

in 24-bit, 8-bit color images, and grayscale images

[6]. In this paper we have used LSB algorithm for

steganography..

2. Cryptographic Algorithms The most complete non-technical account of the

subject is Kahn's the Codebreakers [1-3].

Completed in 1963, Kahn's book covers those

aspects of the history, which were most significant

(up to that time) to the development of the subject.

A cryptographic algorithm transforms

cryptographic key and readable (plaintext) data into

ciphertext that can only be understood by applying

another (possibly the same) cryptographic key and

crypto-algorithm to it [6-9]. If the keys and

algorithms are the same, we have a symmetric or

secret-key crypto system like the DES, IDEA, etc.

If the algorithm involves two different keys, one

for enciphering and the other for deciphering, we have an asymmetric or public-key algorithm like

the RSA, EL-Gamal, … etc. Data protected with

encryption may be transmitted over communication

channels (e.g., a satellite link, telephone lines,

network, etc) before it arrives at its final

destination. For example, data may be input from a

user’s terminal to the user’s program, where it is

processed and then transmitted to a disk file for

storage. Later, the user may retrieve the data and

have it displayed on the terminal. In computer

networks, data may be transmitted from one

location on the network to another for processing or

for any location (computer, terminal, front-end, or

program) where data may be input, stored,

encrypted, processed, routed (switched), or output;

and link for any communication line or data bus

between two nodes. That it is what will be discussed in the next subsection.

2.1. Simplified DES (S-DES): The S-DES encryption algorithm takes an 8-bit

block of plaintext (example: 10111101) and a 10-

bit key as input and produces an 8-bit block of

ciphertext as output. The S-DES decryption

algorithm takes an 8-bit block of ciphertext and the

same 10-bit key used to produce that ciphertext as

input and produces the original 8-bit block of

plaintext. The encryption algorithm involves five

functions: an initial permutation (IP); a complex

function labeled fK, which involves both

permutation and substitution operations and

depends on a key input; a simple permutation

function that switches (SW) the two halves of the

data; the function fK again; and finally a permutation function that is the inverse of the

initial permutation (IP–1). The function fK takes

two 8-bit keys which are obtained from the original

10-bit key [15]. The S- DES algorithm flow is

shown in below figure.

The 10-bit key is first subjected to a permutation

(P10) and then a shift operation is performed. The

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output of the shift operation then passes through a

permutation function that produces a 8- bit output

(P8) for the first sub key (K1). The output of the

shift operation again feeds into another shift and

(P8) to produce the 2nd sub key (K2) [17].We can

express encryption algorithm as superposition

Considering a 24-bpp color image, the image is

split into three matrices (frames) each matrix

containing pixels indicating the intensities of Red, Green and Blue. If m by n is the dimension of that

image, then there will be (m x n) number of pixels

in that image. Hence, the matrices corresponding to

Red, Green and Blue intensities will also have (m x

n) number of pixels.

2.2. Proposed Technique:

(a) Proposed Message Embedding Procedure:

Figure-1: Sender Prospect

Figure-1 shows the sender‟s prospect of

Proposed Technique in which the secret

information is encrypted by using simplified data

encrypted standard (S- DES) encryption algorithm.

Then encrypted message is embedded into cover

image by using Alteration component technique. Image containing the secret data is called stego

image. Next phase is to select the stego key for

encoding. In Embedding process data is hidden by

using Alteration component technique in which

pixels have been replaced by key and secret

message. Firstly key is converted into binary form

and its binary form is filled in the first component

of first pixels. After then, secret message is

converted into binary form and its binary form is

filled in first component of next pixels.

Embedding Algorithm: Step (a): Extract all the pixels in the given

image and store it in the array called Pixel- Array.

Step (b): Extract all the characters in the given

text file and store it in the array called Character-

Array.

Step (c): Extract all the characters from the Stego key and store it in the array called Key-

Array.

Step (d): Choose first pixel and pick characters

from Key- Array and place it in first component of

pixel. If there are more characters in Key- Array,

then place rest in the first component of next pixels,

otherwise follow Step (e).

Step (e): Place some terminating symbol to

indicate end of the key. „0‟ has been used as a

terminating symbol in this algorithm.

Step (f): Place characters of Character- Array in

each first component (blue channel) of next pixels

by replacing it.

Step (g): Repeat step (f) till all the characters has been embedded.

Step (h): Again place some terminating symbol

to indicate end of data.

Step (i): Obtained image will hide all the

characters that we input.

(b) Proposed Message Extraction Procedure:

Figure-2: Receiver Prospect

Figure-2 shows the receiver’s prospect of Proposed Technique in which the sender sends a

stego-image to the receiver or legitimate user. The

legitimate user having the stego key to extract

secret data from stego image. The legitimate user

must have the same key with which the image is

embedded. On Stego image Extracting process is

applied by using Alteration component technique.

After data extraction I get the secret message which

is in encrypted form. Simplified data encryption

standard (S-DES) decryption algorithm is used to

decrypt message. Finally we get the Secret Data

which is embedded.

Extraction Algorithm: Step (a): Consider three arrays. Let they be

Character-Array, Key-Array and Pixel- Array.

Step (b): Extract all the pixels in the given

image and store it in the array called Pixel- Array. Step (c): Now, start scanning pixels from first

pixel and extract key characters from first (blue)

component of the pixels and place it in Key-Array.

Follow Step 3 till we get terminating symbol,

otherwise follow step (d).

Step (d): If this extracted key matches with the

key entered by the receiver, then follow Step 5,

otherwise terminate the program by displaying

message ―Key is not matching.

Step (e): If the key is valid, then again start

scanning next pixels and extract secret message

characters from first (blue) component of next

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pixels and place it in Character Array. Follow Step

(e) till we get terminating symbol, otherwise follow

step (f).

Step (f): Extract secret message from Character-

Array.

2.3. Analysis of the Network Security: A model for network security, in general terms,

is shown in Figure-3. A message is to be

transferred from one party to another across some sort of networks as in the Internet [2]. The two

parties, who are the principals in this transaction,

must cooperate for the exchange to take place. A

logical transformation channel is established by

defining a route through the internet from source to

destination and by the cooperative use of

communication protocols (e.g., TCP/IP) by the two

principals.

Figure-3: A model for network security.

Data is encrypted on a network using

either link or end-to-end encryption. In general,

link encryption is performed by service providers,

such as a data communications provider. Link

encryption encrypts all of the data along a

communications path. Since link encryption also

encrypts routing data, communications nodes need

to decrypt the data to continue routing. End-to-end encryption is generally performed by the end user

organization. Although data remains encrypted

when being passed through a network, routing

information remains visible. It is possible to

combine both types [3]. In the next subsection, the

hash function is introduced.

2.4. Hash Function and Data Integrity: Cryptography hashing functions play a

fundamental role in modern cryptography [4].

Hash functions take a message as input and

produce an output referred to as a hashcode, hash-

result, hash-value, or simply hash. In our model the

hashcode works with the key used in the encryption

procedure like the SHA1, Rip-MD 160, etc. More

precisely, a hash function maps bitstrings of

arbitrary finite length to strings of fixed length as

shown in Figure-4.

Figure-4: General Structure of Secure Hash

Code. The basic idea of cryptographic hash functions

is that a hash-value serves as a compact

representative image (sometimes called an imprint,

digital fingerprint, or message digest) of an input

string, and can be used as if it were uniquely

identifiable with that string. Hash functions are

used for data integrity as a message authentication

code (MAC), allows message authentication by

symmetric techniques. The next subsection

presents steganography algorithms.

2.5. Architecture:

Steganography is a science, which dates back to

ancient times. It has been used by ordinary people,

spies, rulers, governments, armies, etc down

through the ages. It is the original method of

information concealment. Information has been

hidden in drawings, paintings, books, newspapers, in speech, in written word, even in postage stamps

[10].

The Greeks, from the histories of Herodotus,

wrote text on wax-covered tablets. In one story,

Demeratus wanted to notify Sparta that Xerxes

intended to invade Greece. To avoid capture, he

scraped the wax off the tablets and wrote a message

on the underlying wood. He then covered the

tablets with wax again. The tablets appeared to be

blank and unused so they passed inspection by

sentries without question.

The Egyptians, used illustrations to conceal

messages. The idea being that one party could send

the illustration to the other in reasonable

confidence that if the messenger was questioned

then the illustration would not arouse any interest

from his enemies.

The Chinese, would often write on thin silk or paper, which they rolled into a ball and covered in

wax. A messenger hid the ball somewhere on his

person, sometimes by swallowing it. This is a form

of steganography.

Steganography is the art of communicating

messages by embedding them into multimedia data

(usually digital images). It is desired to maximize

the amount of hidden information (embedding rate)

while preserving security against detection by

unauthorized parties. Steganography system Like

the Least Significant Bit “LSB” should fulfill the

same requirements posed by the "Kerckhoff

principle" in cryptography [11].

Architecture consists of four basic blocks

a) Encryption: Matrix Mapping Method for

Symmetric Key Cryptography

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b) Steganography: Modified BPCS

c) Decryption Matrix Mapping Method for

Symmetric Key Cryptography

d) Desteganography: Modified BPCS

Figure-5: Architecture Diagram of System

a) Encryption: Matrix Mapping Method for Symmetric Key

Cryptography In this algorithm, using the key we

generate a mapping matrix. Every bytes of the mapping image is unique and is with respect to key.

The mapping matrix is of size 16 by 16.This

algorithm is influenced by Applied cryptography in

Java (Partida, A.Andina, D.Atos).

Algorithm:

1) The source file is opened for reading in

binary mode.

2) Every bytes of the source file is read and

converted into its equivalent 8-bit binary number.

3) Split the 8-bit binary number into 4-bit higher

and lower nibble number.

4) Convert these two 4-bit nibbles into its

equivalent decimal value.

5) With the help of these two decimal values

pick up a pixel from the mapping matrix. Where

higher nibble equivalent decimal value acts as row

indicator and lower nibble equivalent decimal value acts as column indicator for mapping image.

6) Replace the original pixel with the byte

selected from mapping matrix.

7) Encrypted file gets generated as the above

process is repeated for all the pixels.

b) Steganography: Modified BPCS: Our new Steganography uses an image as the

vessel data, and we embed secret information in the

bit- planes of the vessel. This technique makes use

of the characteristics of the human vision system

whereby a human cannot perceive any shape

information in a very complicated binary pattern.

We can replace all of the “noise-like” regions in the

bit-planes of the vessel image with secret data

without deteriorating the image quality. This

algorithm is influenced by Principle and application

of BPCS-Steganography (Eiji Kawaguchi and Richard O.Eason).This algorithm is termed as

Modified “BPCS-Steganography,” which stands for

Bit-Plane Complexity Segmentation

Steganography. Input data will be vessel image and

data to embed in byte format. Load the vessel

image into memory. Get width and height of the

memory image. Generate a threshold value. For

each pixel get red, green and blue values of current

pixel.

Algorithm: Real Image and data to Embed in byte array

format is given as input.

1) Load the vessel image into memory. 2) Get a "readable pen" for the memory image.

3) Get width and height of the memory image.

4) Generate a threshold value.

5) Loop for all rows of memory image

Loop for all cols of memory image

a) Using the "readable pen" get red, green

and blue values of current pixel.

b) If red <= threshold and green <=

threshold and blue <= threshold then

* mark the pixel as NOISY (store in a

list).

6) If NOISY pixel list size >= size of data to

embed go to step 8.

7) Raise Error "Content length is more than

embedding capacity of Vessel Image".

8) Convert the Data to embed into SECRET

BLOCKS a) Create a empty list to hold secret blocks

b) Loop for every bytes of input data

* conjugate the byte

* store the conjugated byte into secret block

list.

9) Get a "writable pen" for the memory image.

10) Loop for every element of NOISY pixel list

a) Embed 2 bytes of data from SECRET

blocks into red, green and blue bands of noisy

pixel.

b) Using the writable pen write the pixel into

memory image.

11) Write back the memory image into IMAGE

FILE.

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Figure-6: Algorithm to encrypt data and embed it

into image

c) Decryption: Matrix Mapping Method for

Symmetric Key Cryptography: In this algorithm, using the key we generate a

mapping matrix. Every bytes of the mapping image

is unique and is with respect to key. The mapping

matrix is of size 16 by 16.

Algorithm: 1) The encrypted file is opened for reading in

binary mode.

2) Every bytes of the encrypted file is read and

converted into its equivalent 8-bit binary number.

3) Match the byte in the mapping matrix and

find out row and column number of the matched

byte.

4) Form 2 nibbles using the row number and

column number. Generate 8-bit binary number

from 4-bit higher (row) and lower (column) nibble

number.

5) Substitute this generated 8 bit binary data in

place of the current byte.

6) Original file gets generated as the above

process is repeated for all the pixels.

Get the bytes from image using Desteganography and use the key to generate

decryption matrix. Now match the byte which we

got from image with each matrix element. And get

corresponding row and column number of matched

element. Convert the obtained row and column

number into binary format. Deconjugate these two

numbers which represents original data.

d) Desteganography: Modified BPCS:

Figure-7: Algorithm to decrypt data and extract

from image

Image having embedded data is given as input.

Algorithm:

1) Load the image into memory.

2) Get a "readable pen" for the memory image.

3) Get width and height of the memory image.

4) Generate a threshold value.

5) Loop for all rows of memory image

Loop for all cols of memory image

a) Using the "readable pen" get red, green

and blue values of current pixel.

b) If red <= threshold and green <= threshold and blue <= threshold then

mark the pixel as NOISY (store in a list)

6) Loop for every element of NOISY pixel list

a) Extract bytes of data from red, green and

blue bands of noisy pixel.

b) Deconjugate the secret blocks and form

data bytes.

c) Concatenate the data in a result buffer.

7) Write back the result buffer into a FILE Input

data will be image having embedded data. Load the

image into memory. Get width and height of the

memory image. Generate a threshold value.

3. Image Compression To a computer, an image is an array of

numbers that represents light intensities at various

points (pixels) [10-12]. These pixels make up the

image’s raster data. A common image size is

640x480 pixels and 256 colors (or 8 bits per pixel).

Such an image could contain about 300 kilobits of

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data. Digital images are typically stored in either

24-bit or 8-bit files. A 24-bit image provides the

most space for hiding information; however, it can

be quite large (with the exception of JPEG images).

All color variations for the pixels are derived from

three primary colors: red, green, and blue. Each

primary color is represented by 1 byte; 24-bit

images use 3 bytes per pixel to represent a color

value. These 3 bytes can be represented as hexadecimal, decimal, and binary values. In many

Web pages, the background color is represented by

a six-digit hexadecimal number- actually three

pairs representing red, green, and blue. A white

background would have the value FFFFFF: 100

percent red (FF), 100 percent green (FF), and 100

percent blue (FF). Its decimal value is 255, 255,

255, and its binary value is 11111111, 11111111,

11111111, which are the three bytes making up

white. This definition of a white background is

analogous to the color definition of a single pixel in

an image. Pixel representation contributes to file

size. For example, suppose a 24-bit image 1024 x

768 - a common resolution for high-resolution

graphics. Such an image has more than 2 million

pixels, each having such a definition, which would

produce a file exceeding 2 Mbytes. Such a huge size for the cover image is considered as an

advantage for embedding larger messages. On the

other hand, such 24-bit images are still relatively

uncommon on the Internet, their size would attract

attention during transmission. Thus, using image

compression for the cover image can solve such

contradiction and would be beneficial, if not

necessary, to transmit such a file. How to embed

the data will be available in the next subsection.

1.1. Embedding Data: Embedding data, which is to be hidden,

into an image requires two files. The first is the

innocent-looking image that will hold the hidden

information, called the cover image. The second

file is the message - the information to be hidden.

A message may be plain text, ciphertext, other images, or anything that can be embedded in a bit

stream. When combined, the cover image and the

embedded message make a stego image. A stego-

key (a type of password) may also be used to hide,

and then later decode, the message [12]. In 8-bit

color images such as GIF files, each pixel is

represented as a single byte, and each pixel merely

points to a color index table (a palette) with 256

possible colors. The pixel’s value, then, is between

0 and 255. The software simply paints the

indicated color on the screen at the selected pixel

position. When considering an image in which to

hide information, one must consider the image as

well as the palette. Obviously, an image with large

areas of solid colors is a poor choice, as variances

created from the embedded message will be

noticeable in the solid areas. Once selecting a

cover image, one must decide on a technique to

hide the information wanted to embed.

1.2. Digital Image Preprocessing: In the embedding module, all of the gray

scales of the pixels within a block will be modified

such that the mean intensity value of the block will

be equal to the closest center of an interval. If there

are too many pixels whose gray scales are near the gray scale boundary, i.e., 0 or 255, it will be hard to

adjust the mean intensity value while maintaining

the image fidelity. For example, the mean value of

a block is 195, and half of pixels in this block have

gray scale 255, and the desired interval center is

210. Since half of pixels could not be adjusted,

other pixels will be added 30 on the average. This

change may be too large to maintain the image

fidelity. Thus, a preprocessing is provided to make

all gray scales away from the boundary [12, 13].

Many steganography experts recommend using

images featuring 256 shades of gray. Gray-scale

images are preferred because the shades change

very gradually from byte to byte, and the less the

value changes between palette entries, the better

they can hide information. Figure-8 shows a gray-

scale palette of 256 shades.

Figure-8: Gray-scale palette of 256 shades.

1.3. The Proposed Kbsa Steganographic: In this section, a block diagram of the package

model KBSA [4] stages for multimedia

communications is presented as shown in Figure-9.

Many experiments were done in the lab using

image files and text message. Only a sample is

presented and it is shown that the stego image

cannot indicate that it contains any information so,

no one might suspect in that innocent image and the extracted message is same like the original

message.

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Figure-9: The block diagram of a general KBSA

package model using compressed, hashed,

encrypted and steganographic algorithms.

More recently, people are hiding secret

messages in graphic images. Replace the least

significant bit of each byte of the image with the

bits of the message. The graphical image will not

change appreciably - most graphics standards

specify more gradations of color than the human

eye can notice - and the message can be stripped

out at the receiving end. One can store a 64-kilobyte message in a 1024 × 1024 grey-scale

picture this way. Steganography goes well beyond

simply embedding text in an image. It also pertains

to other media, including voice, text, binary files,

and communication channels.

4. Experiments and Results This example is accomplished by applying the

Least Significant Bit Insertion (LSB). Stego-keys

are used to generate the stego-tables and table indices. In 24-bit images, to hide an image in the

LSBs of each byte of a 24-bit image, you can store

3 bits in each pixel (RGB). For example, the letter

A can be hidden in three pixels (assuming no

compression). The original raster data for 3 pixels

(9 bytes) may be (the highlighted bits are the least

significant bit in each byte):

(00100111 11101001 11001000)

(00100111 11001000 11101001)

(11001000 00100111 11101001)

The binary value for letter A is 10000011.

Inserting the binary value for A in the three pixels

would result as

(00100111 11101000 11001000)

(00100110 11001000 11101000)

(11001001 00100111 11101001)

The underlined bits are the only four actually changed in the 8 bytes used. On average,

LSB requires that only half the bits in an image be

changed. You can hide data in the least and second

least significant bits and still the human eye would

not be able to discern it. Here is an example in a

large scale of 1024 x 768 Girl and Baboon cover

image before embedding the encrypted data as

shown in Figures-10 (a) and (b) respectively.

Figure-10: Two RGB Cover Images (a) Girl (b)

Baboon.

A 1024 x 768 Girl image has the potential

to hide a total of 2,359,296 bits (294,912 bytes) of

information and a 1024 x 768 Baboon image has

the potential to hide a total of 1,656,789 bits

(207,099 bytes) of information. The relative

entropy between the cover image and the stego

image is zero. The resulting stego and the cover

images should be indistinguishable by the naked

eye. . Here is an example in a large scale of 1024

x 768 Girl and Baboon cover image after

embedding the encrypted data as shown in Figures-11 (a) and (b) respectively.

Figure-11: Two Stego images Created by our

approach (a) Girl (embedded data are 2,359,296

bits (294,912 bytes)). (b) Baboon (embedded data

are 1,656,789 bits (207,099 bytes)). An advantage of the proposed scheme is

that the extracting algorithm is simple and easy to

implement. When receiving a stego-image, the

receiver uses the same stego-keys to generate the

same stego-tables and table indices as those used in

the embedding process to extract the originally

encrypted data. Then decryption and

decompression procedures are consequently done

to obtain the plaintext. He also do the MAC check

to be sure that the data is not modified through the

communication channels. Some of the advantages

of using K-bit LSB Steganography are:

1) Gives high data embedding capacity.

2) Provides high and imperceptible quality stego

images.

3) Provides high security.

5. Conclusion & Future Enhancements In this paper, we presented an

implementation to a package that contains many

cryptosystems, hash functions, steganography and

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ISSN:2229-6093

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compression algorithms. This package might be

used to deal to secure multimedia in

communication channels as in the Internet.

Hashing the key is used as a message

authentication code (MAC). Cryptography and

steganography methods are combined to make a

robust model that can survive image manipulation

and attacks. The more information that is made

available on the Internet, the more owners of such information need to protect themselves from theft

and false representation. The presented Secured

Package Machinery achieved the two cryptographic

principals’ objectives: (i) Secrecy (or privacy), to

prevent the unauthorized disclosure of data and (ii)

Authenticity (or integrity), to prevent the

unauthorized modification of data.

Steganography’s function in security is to

supplement cryptography, not replace it. If a

message is encrypted and then embedded in an

image, video, or voice, it becomes even more

secure. If an encrypted message is intercepted, the

interceptor knows the text is an encrypted message.

Nevertheless, with steganography, the interceptor

may not know that a hidden message even exists.

The work accomplished during this project

can be summarized with the following points: 1) In this project we have presented a new system

for the combination of cryptography and

Steganography using matrix mapping method for

Symmetric Key Cryptography and modified BPCS

technique for Steganography which could be

proven a highly secured method for data

communication in near future.

2) Steganography especially combined with

cryptography, is a powerful tool which enables

people to communicate without possible

eavesdroppers even knowing there is a form of

communication in the first place. The proposed

method provides acceptable image quality with

very little distortion in the image.

3) The main advantage of this

Cryptosteganography System is hybrid

combination of cryptography and Steganography which provides double layer security.

In future video or audio files can be used

to hide data instead of images.

6. References [1] William Stallings; Cryptography and Network

Security: Principals and Practice, Prentice Hall

international, Inc.; 2002.

[2] Oded Goldreich; Foundations of Cryptography,

China Machine Press, 2003. [3] Jae K. Shim, Anique A. Qureshi and Joel G.

Siegel, The International Handbook of Computer

Security, Glenlake Publishing Company, Ltd.,

Glenlake Publishing Company, Ltd., 2000.

[4] H. M. Al-Barhmtoshy and Emad S. Ibrahim

“Key-Based Security Algorithm (KBSA)”, INFOS

2002, Proceedings of the 1st International

Conference on Information and systems, Cairo,

Egypt, June, 2002.

[5] Emad S. Ibrahim and Ahmed M. Gohar, An

Encrypted Compression Model For Aerial Images,

ICAIA’ 2003, proceedings of the 11th International

Conference on Artificial Intelligence Applications,

Cairo, Egypt, February, 2003.

[6] Ma Shilong, Emad S. Ibrahim, and Hala A.

Bayoumy, An introduction to Admire in China (Advanced Multimedia Interactive Real-time

Environment), ICAIA’ 2003, proceedings of the

11th International Conference on Artificial

Intelligence Applications, Cairo, Egypt, February,

2003.

[7] Emad S. Ibrahim and Hala A. Bayoumy,

“Novel Authentication Approach Using The

MSPC”, the Proceedings of the 7th IEEE

International Conference on Intelligent Engineering

Systems, INES2003, Assiut - Luxor, Egypt, March,

2003.

[8] Emad S. Ibrahim and Ahmed M. Gohar,

“Kappa Test Towards Cryptosystems”, the

Proceedings of the 7th IEEE International

Conference on Intelligent Engineering Systems,

INES2003, Assiut - Luxor, Egypt, March, 2003.

[9] Aly A. Somaie, Hassan M. Farahat and Emad S. Ibrahim, “Technical Discussion on

Cryptosystems”, AEIC 2003, Proceedings of AL-

Azhar engineering 7th International Conference,

Cairo, Egypt, April, 2003.

[10] Neil F. Johnson, Zoran Duric, Sushil Jajodia,

Information Hiding: Steganography and

Watermarking - Attacks and Countermeasures,

Kluwer Academic Publishers, 2000.

[11] Ross J. Anderson, Fabien A.P. Petitcolas, On

the Limits of Steganography, IEEE Journal of

Selected Areas in Communications, 16(4):474-481,

May 1998

[12] B. Pfitzmann, “Information Hiding

Terminology,” Proc.First Int’l Workshop

Information Hiding, Lecture Notes in Computer

Science No. 1,174, Springer-Verlag, Berlin, 1996,

pp. 347-356. [13] Yeuan-Kuen Leea and Ling-Hwei Chen,

“High capacity steganographic model”, IEE Proc.-

Vis. Image signal Process., Vol. 147, No. 3, June

2000.

[14] http://www.jjtc.com/stegdoc/stegdoc.html.

[15] E. Biham, A. Shamir. “Differential

cryptanalysis of DES-like cryptosystems,” Journal

of Cryptology, vol. 4, pp. 3-72, January 1991.

[16] C. B. Smith and S. S. Agaian, “On noise,

steganography, and the active warden,” Multimedia

Forensics and Security, Chapter VIII, Information

Science Reference, PA, 2008, pp. 139-162.

[17] K. Kim, S. Park, and S. Lee, “Reconstruction

of s2DES S–Boxes and their Immunity to

DifferentialCryptanalysis,” Proceedings of the

1993 Korea–Japan Workshop on Information

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IJCTA | July-August 2014 Available [email protected]

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ISSN:2229-6093

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Security and Cryptography, Seoul, Korea, 24–26

Oct 1993, pp. 282– 291.

[18] Abhishek Patidar Gajendra Jagnade * Laxmi

Madhuri Pranay Mehta Ronak Seth, “Data

Security Using Cryptosteganography in Web

Application” Computer Engineering and Intelligent

Systems, ISSN 2222-1719 (Paper) ISSN 2222-2863

(Online) Vol 3, No.4, 2012.

Rituraj Rusia et al, Int.J.Computer Technology & Applications,Vol 5 (4),1495-1505

IJCTA | July-August 2014 Available [email protected]

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ISSN:2229-6093


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