A PVD based high capacity steganography algorithm with embedding in non-sequential position

Abstract

Modern research in Steganography focuses on increasing the capacity without keeping any perceptible signature into the stego-media. In this work, we present a pixel value difference (PVD) based high capacity methodology. Embedding is not restricted only to high contrast pixel pairs. Low contrast pairs are also considered to enhance the capacity. Embedding process varies depending on the local contrast of the pair. Secret message is encrypted before embedding and pixels pairs are chosen in a non-sequential manner, rendering the methodology more secure. Experiment is performed on more than two hundred images. It is observed that embedding by proposed technique is visually imperceptible and can withstand various types of attacks. The benchmark test like StirMark analysis also indicates the strength of the work. Comparison of performance with a number of other methods shows that proposed methodology maintains high PSNR with enhanced capacity.