Today worldwide, security and data hiding concerns are increasing day by day. Various security devices, systems and algorithms are used at places for the same. Most of these systems are implemented at places like airports, military areas, private or government offices.
Steganography means covered or hidden writing. The objective of steganography is to send message through some innocuous carrier. The message to be sent could be a text, an image or an audio file. Steganography techniques prevent the fact that a secret message is being sent at all.
Steganographic security is mostly influenced by the type of cover media; the method for selection of places within the cover that might be modified; the type of embedding operation; and the number of embedding changes that is a quantity closely related to the length of the embedded data. Given two embedding schemes that share the first three attributes, the scheme that introduces fewer embedding changes will be less detectable.