SECURED CRYPTO STEGANO DATA HIDING USING IMPROVED LEAST SIGNIFICANT BIT SUBSTITUTION AND ENCRYPTION

Abstract

Communication has always been an integral part of our existence. With the rapid advancement in Internet and networking technologies during the recent years, communication and information exchange have become much easier and faster but at the same time the issues related to data security and confidentiality have become a major concern of time. To cater to this need of information security, a number of hidden and secret communication techniques such as cryptography, steganography and watermarking have been developed. These are the practical means to provide security services and are becoming a powerful tools in many applications for information security. Cryptography scrambles a message so it cannot be understood whereas the Steganography hides the message so that it cannot be seen. In this method we first encrypt a message using an algorithm based on Fibonacci series or Rijndael cryptographic algorithm and then embed the encrypted message inside an image using Least Significant Bit (LSB) substitution method. Digital images often have a large amount of redundant data and for this reason it is possible to hide message inside image file. Image steganography is about exploiting the limited power of the human visual system where we hide information in the least significant bit of the image data. This embedding method is based on the fact that the least significant bit in an image can be thought of as random noise, and consequently they become less responsive to any change on the image. The combination of these two methods will enhance the security of the data embedded. This combinational methodology will satisfy the requirements such as capacity, security and robustness for secure data transmission over an open channel.