A study on steganographic techniques

Steganography is the process of hiding secret information inside a data source. It keeps not only the message, but also the existence of the message as a secret. It has applications in different fields such as defense, medical, online transactions etc. It is mainly used in situations where the confidentiality of information is of prime importance in communication. In steganography, information can be hidden in carriers such as text files, images, audio and video. Based on factors such as carrying file, type of message to be embedded, methods of compression used etc., the technique used in steganography can differ. The strength of a steganographic technique lies in its capacity to keep the message, as secret as possible and also the amount of data that can be hidden, as large as possible. In spite of the fact that numerous approaches already exist in steganography, researches are going on in this field. This paper gives a survey on the methods used in this area.