A HEVC Steganography Algorithm Based on DCT/DST Coefficients with BLB Distortion Model

Currently, video steganography has become more important for information security. Most of the previous work focused on preventing the intra-frame distortion drift without considering the intra-block distortion caused by steganography and only embedded data in small-sized blocks. With higher resolution, large-sized blocks are more in HEVC videos. It is a large waste of embedding capacity if they are not used to hide data. In this paper, a HEVC steganography algorithm based on DCT (Discrete Cosine Transform)/DST (Discrete Sine Transform) coefficients with BLB (Block Based) distortion model is proposed. The proposed BLB distortion model considers both inter-block distortion and intra-block distortion. The algorithm uses the intra-frame error propagation-free method to hide data in small-sized blocks to eliminate inter-block distortion. Especially, the STC (Syndrome Trellis Codes) framework is used to hide data in large-sized blocks to reduce intra-block distortion. Experiments confirm that the proposed algorithm improves the embedding capacity largely with the same level of visual quality and compression bitrate as that of the previous work, and can resist the latest HEVC video steganalysis method.