A robust coverless video steganography based on maximum DC coefficients against video attacks

Coverless steganography has been of great interest in recent years, since it is a technology that can absolutely resist the detection of steganalysis by not modifying the carriers. Most existing coverless steganography algorithms select images as carriers, and few studies are reported on coverless video steganography. Compared with images, the video sequence contains more information. However, there are few methods that can be used in coverless video steganography for resisting video compression and other video attacks. In this paper, a novel coverless video steganography algorithm based on maximum Direct Current (DC) coefficients against video attacks is proposed. Firstly, a Gaussian distribution model of DC coefficients considering the video coding process is built, which indicates that the distribution of changes for maximum DC coefficients in a block is more stable than the adjacent DC coefficients. Then, a novel hash sequence generation method based on the maximum DC coefficients is proposed. After that, the video index structure is established to speed up the efficiency of searching videos. In the process of hiding, the secret information is converted into binary segments, and the video whose hash sequence equals the secret information segment is selected as the carrier according to the video index structure. Experimental results and analysis show that the proposed algorithm can resist most kinds of attacks because of the strong robustness of the maximum DC coefficients. What's more, compared with the state-of-the-art work, the proposed algorithm has achieved apparent advantages in the resistance to the mainstream video coding and frame deletion, and gotten much higher effective capacity.