A High Embedding Capacity Approach to Adaptive Steganography

Steganography, ("covered writing" in Greek) is the science of communicating in a hidden manner. An ideal steganographic technique embeds message information into a carrier cover image with virtually imperceptible modification of the cover image. However in practice it is very difficult to add message information without its effect on the cover 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. Most of the adaptive steganographic methods in the literature use either local or global features of an image for embedding the message, such that the obtained steganographic images are imperceptibly innocuous to human eyes. 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 in this paper 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. We believe this approach shall improve the secrecy of communication of images and lead to better digital information management.