Efficient large payloads ternary matrix embedding

Matrix embedding (ME) can be exploited to improve the embedding efficiency for steganography by making fewer changes to the cover data. In ME, the sender and recipient agree on a parity check matrix (PCM) in advance. The PCM will be used by the sender to embed secret message into the cover data and later by the decoder to extract the embedded message. The embedding performance of ME is greatly influenced by the PCM thus the choice of PCM is crucial for ME. On the other hand, since larger sized PCM usually leads to higher embedding efficiency, how to keep the balance between the computational complexity and the embedding efficiency is also an important problem of ME. Based on these considerations, an efficient ternary ME method for large payloads data embedding is proposed in this paper. We utilize a specific matrix construction for PCM to improve embedding efficiency and a sub-optimal search strategy to reduce the computational complexity. The experimental results show that the proposed method achieves good embedding efficiency at low time cost and it outperforms some state-of-the-art works. For example, for a cover image with 512 × 512 pixels at an embedding rate of 1 bit per pixel, the proposed method can be implemented within 0.5 second in a personal computer with a rather high embedding efficiency as 3.89.