A New High Capacity Video Steganography Scheme Using Differential Directional Pixogram

摘要

A video signal is a collection of images (frames) presented successively at a constant rate. To have a meaningful video segment, the images that compose the video segment should be related to each other. Therefore, the time domain of a video segment is a great source of data redundancy. Utilizing data redundancy is the driving force for data hiding schemes. This paper proposes the Differential Directional Pixogram (DDP) scheme to optimally exploit the temporal redundancy in a video segment. The idea is to extract a vector of pixels in the direction of the motion in each scene. Thus, it is expected that this vector will be composed of homogeneous pixels. The secret pixels are then embedded in the Discrete Cosine Transform (DCT) coefficients since the DCT has a powerful ability to express a highly correlated signal within few significant DCT coefficients leaving a large amount of insignificant DCT coefficients. As a result, the proposed DDP scheme is able to hide a substantial amount of secret data while achieving outstanding stego quality compared to competitive video steganography schemes.