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    Image Steganography in LSB: Presented By: Ritu Agarwal 9910103516

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    Moni
    The document discusses image steganography in least significant bits (LSB). It explains that steganography hides information by embedding messages within images without altering the image in a perceptible way. The document outlines how an encryption algorithm like RSA can be used along with steganography for two-level security. It also describes the process of hiding text in an image by replacing the LSB of each pixel with bits of the text file.

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    Image Steganography in LSB: Presented By: Ritu Agarwal 9910103516

    Uploaded by

    Moni
    28 views17 pages
    The document discusses image steganography in least significant bits (LSB). It explains that steganography hides information by embedding messages within images without altering the image in a perceptible way. The document outlines how an encryption algorithm like RSA can be used along with steganography for two-level security. It also describes the process of hiding text in an image by replacing the LSB of each pixel with bits of the text file.

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    The document discusses image steganography in least significant bits (LSB). It explains that steganography hides information by embedding messages within images without altering the image in a perceptible way. The document outlines how an encryption algorithm like RSA can be used along with steganography for two-level security. It also describes the process of hiding text in an image by replacing the LSB of each pixel with bits of the text file.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    28 views17 pages

    Image Steganography in LSB: Presented By: Ritu Agarwal 9910103516

    Uploaded by

    Moni
    The document discusses image steganography in least significant bits (LSB). It explains that steganography hides information by embedding messages within images without altering the image in a perceptible way. The document outlines how an encryption algorithm like RSA can be used along with steganography for two-level security. It also describes the process of hiding text in an image by replacing the LSB of each pixel with bits of the text file.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    of 17

    IMAGE

    STEGANOGRAPHY IN LSB

    Presented by:
    Ritu Agarwal
    9910103516
    CRYPTOGRAPHY & STEGANOGRAPHY
    CRYPTOGRAPHY :

    The art of protecting information by transforming it


    (encrypting it) into an unreadable format, called cipher text.
    Only those who possess a secret key can decipher (or decrypt)
    the message into plain text.

    STEGANOGRAPHY:

    Steganography is basically referred as hidden writing. It is


    entirely different from cryptography. In cryptography ,we
    basically perform the encryption and decryption by changing
    the text into another form.
    STEGANOGRAPHY

    But in steganography, we do not change the text into


    another form but just hide it into the image or audio so
    that the attacker doesn’t know about the hidden message.
    Introduction to RSA Algorithm

    RSA algorithm is a part of cryptography in which a text


    message is hidden in some other form. Using steganography
    alongwith RSA algorithm works for 2-level security.
    TYPES

    Types of Steganography:

    1. Image Steganography
    2. Text Steganography
    3. Video Steganography
    4. Protocol Steganography
    5. Audio Steganography
    HOW STEGANOGRAPHY WORKS

     Now the question is how steganography works!!

     In steganography first we select the text or any file that we


    want to send to another person.

     Then we select the image or audio file in which we want


    to hide our file(containing message).
     Then we use the steganography software for encryption.

     After encryption the text file is now converted in an image


    file which contains our confidential data.

     Then the receiver will also use the same software for
    decryption.
    IMAGE STEGANOGRAPHY
    WITH RSA ALGORITHM
     How the image steganography works:

    Before encrypting file into image file, we use the well


    defined RSA Algorithm to increase the security of the data
    transmission.
    Then, we use this encrypted message to be encrypted
    o9nce again into the image file.
     Every image is formed of the pixels. There are a number
    of pixels in the image. Every pixel is formed of 24 bits.
    Each pixel has 8 bits of red color, 8 bits of green color and
    8 bits of blue color(RGB).
     Also the file that we want to send to the receiver is also formed
    from a number of bits.

     Now the next step is to store every 3 bits of the file in every
    pixel’s Least Significant bit (LSB) i.e. 1-1 bit in 8th bit of red ,
    blue, green color bits.

     In this way our encryption will be done.

     In this way, decryption can also be performed by extracting the


    8th bit of every color from each pixel.
    CODE ANALYSIS

     First we extract the image by using


    Image im=Image.fromfile(imagepath);

    Get the height and width by im.height and im.width

    Get the pixel info by using


    Bitmap bt=new bitmap(im);
    IMAGE STEGANOGRAPHY

     Now we extract the file and get the fileinfo by using


    FileInfo fi=new FileInfo(filepath)

    We convert the file into stream of bytes by using


    fc=File.ReadAllBytes(file path)
     Now we perform the encryption

    In encryption function, we start a loop and in loop we access


    every byte of the file 3 times .

    We also use the functions ‘byte2bool’ and ‘bool2byte’ which


    converts byte into bits and vice-versa
     Starting from LSB, in the first iteration we first put 3 bits
    of the file in the red pixel, then in the green one and in
    third i.e. blue we put 2 bits.

     The chromatic influence of blue color is maximum for


    human eye so we change only 2 bits of it.

     When all the bytes of the file are not able to store in the
    last bits of every color then we start to replace the 7 th bit
    of every color.
     In this way the storing capacity of the image file increases
    but little noise is also increased in the image

     In the same way we can perform the decryption


    THANK YOU

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