A Comparative Study of Various image Steganographic Techniques Used for Information Hiding

The staggering growth in communication technology and usage of public domain channels (i.e. Internet) has greatly facilitated transfer data. However, such open communication channels have greater vulnerability to security threats causing unauthorized information access. Traditionally, encryption is used to realize the communication security. Today, HTML pages and Spam Emails are also being used for steganography. With the help of steganography, people can hide the information which is paramount and confidential for them. Steganography is the art of hiding the fact that communication is taking place, by hiding information in other information. Many different carrier file formats can be used. For hiding secret information in images, there exist a large variety of steganographic techniques some are more complex than other and all of them have respective strong and weak points. Steganography is a technology where modern data compression, information theory, spread spectrum, any cryptography technologies are brought together to satisfy the need for privacy on the Internet.