Key Based Image Steganography using Dwt and Chaotic Map

Steganography is used to increase the security of message sent over the network. Steganography is a Greek origin word which means “hidden writing”. Steganography can be divided into two words Steganos which means “secret” and graphic means “writing”. Image Steganography has been widely studied by researchers. A Steganography technique that uses image as a cover media is called an image Steganography. This paper mainly focuses on key based image Steganography using DWT (discrete wavelet transformation) and chaotic map. In this, the major focus on the secrecy and privacy of information. DWT is used to perform on a grey level cover image for secrecy and on the other hand chaotic map is applied on the secret image for privacy. DWT is used to transform cover image from spatial domain into frequency domain. Transformation can be applied over the entire image to block throughout the image. With the help of this technique we can hide the text within an image and hiding the image within an image and also recover that text and image.