Motion vector based video steganography using homogeneous block selection

In recent steganographic literature, video steganography becomes popular due to its capability of accommodating higher payload. Since the video is transmitted mostly in a compressed format, compressed domain parameters are a natural choice for data embedding. In this paper, a motion vector based video steganographic method is proposed. For embedding the secret bit stream, the embedding motion vectors are selected for the homogeneous regions of the reference frame. Since homogeneous or smooth regions contain macro blocks with similar prediction error blocks, it helps to reduce the chance of detection by masking the embedding noise with similar prediction error among neighbouring macro blocks. The efficient search window and polar orientation based embedding technique are used to improve the imperceptibility against standard steganalysis schemes. A set of experiments is been carried out to justify the efficacy of the proposed scheme over the related existing steganographic methods.