دانلود An advanced Diffie-Hellman approach to image steganography

Abstract

Diffie-Hellman  key  exchange  is  one  of  the  most  popular key exchange algorithms used in cryptography. Steganography is the approach  of  hiding  information  in  a  medium.  When  that  medium  is an  image  it  is  called  as  image  steganography.  The  most  popular image steganography algorithm in use presently is the Least Significant bit Algorithm (LSB). However this algorithm has proved to be easy to crack and hence rather insecure. The proposed algorithm uses a variation of the Diffie-Hellman algorithm to determine  the  pixel  positions  of the  image  to  embed  the  information  in.  Both  the  sender  and  receiver  maintain  private  keys.  Along  with this  a  public  key  is  shared  between  them.  The  sender  sends  a  public key to the receiver and vice versa. This public key is nothing but the product of the private key with the public key. The shared secret key is  then  the  public  key  received  multiplied  with  the  private  key  of  each. Now this value obtained is considered to be the pixel to embed data  in.  So  all  pixels  with  multiples  of  this  value  are  embedded  first using LSB. If still some data persists, then the shared key is substracted  by  1  and  all  multiples  of  this  new  value  are  then  filled.  The process is repeated till the entire information is hidden.