A Novel Approach to Develop a Secure Image based Steganographic Model using Integer Wavelet Transform

Steganography is a process that involves hiding a message in an appropriate carrier like image or audio. It is of Greek origin and means "Covered or hidden writing". The carrier can be sent to a receiver without any one except the authenticated receiver only knows existence of the information. Steganography is an emerging area which is used for secured data transmission over any public media. Considerable amount of work has been carried out by different researchers on steganography. In this paper, a specific image based steganography technique for communicating information more securely between two locations is proposed. The author incorporated the idea of secret key for authentication at both ends in order to achieve high level of security. Before the embedding operation the cover image is segmented in different objects through normalized cut. As a further improvement of security level, the information has been permuted, encoded through integer wavelet transformation by lifting scheme and segmented in different parts and then finally each part has been embedded through modified lsb embedding method on different cuts of the cover image to form different stego objects. Finally stego image is formed by combining different stego objects and transmit to the receiver side. At the receiver side different reverse operation has been carried out to get back the original information. The proposed embedding approach works by selecting the embedding pixels using some mathematical function and then finds the 8 neighborhood of the selected pixel and map each bit of the secret message in each of the neighbor pixel in a specified manner. Before embedding a checking has been done to find out whether the selected pixel or its neighbor lies at the boundary of the image or not.