An improved DCT-based perturbation scheme for high capacity data hiding in H.264/AVC intra frames

Recently, Ma et al. proposed an efficient error propagation-free discrete cosine transform-based (DCT-based) data hiding algorithm that embeds data in H.264/AVC intra frames. In their algorithm, only 46% of the 4 × 4 luma blocks can be used to embed hidden bits. In this paper, we propose an improved error propagation-free DCT-based perturbation scheme that fully exploits the remaining 54% of luma blocks and thereby doubles the data hiding capacity of Ma et al.'s algorithm. Further, in order to preserve the visual quality and increase the embedding capacity of the embedded video sequences, a new set of sifted 4 × 4 luma blocks is considered in the proposed DCT-based perturbation scheme. The results of experiments on twenty-six test video sequences confirm the embedding capacity superiority of the proposed improved algorithm while keeping the similar human visual effect in terms of SSIM (structural similarity) index.

► We designed an improved DCT-based perturbation scheme that allows hidden data to be embedded in all luma blocks in H.264/AVC intra frames.
► The proposed embedding scheme can significantly improve the capacity of the previous approach, but not exacerbate the error propagation problem.
► We also present a theorem to verify the feasibility of the proposed embedding scheme.