A Filtering Based Approach to Adaptive Steganography

An ideal steganographic technique embeds message information into a carrier image with virtually imperceptible modification of the image. Adaptive steganography comes closer to this ideal since it exploits the natural variations in the pixel intensities of a cover image to hide the secret message. The objective of adaptive steganographic methods in the literature is to embed a message, such that the obtained steganographic images appear unmodified. These approaches are limited due to use of local image information and the lack of parametric control of embedding capacity. In this paper a new method of adaptive steganography is proposed, that uses both global and local image features. The novel approach allows for a high embedding capacity and enhanced security. A detailed algorithm is presented along with results of its application on some sample images. A comparison between the features of existing adaptive steganographic methods and the new method are also presented