关键词: 信息隐藏, 嵌入容量, 频域系数, 压缩不变性, 离散余弦变换, 逆变换

Abstract: Hiding capacity, robustness and invisibility are some of the key parameters in information hiding system. Moreover, these parameters are seriously impacted by the difference of Discrete Cosine Transform (DCT) coefficients in DCT domain hiding algorithm. Embedded capacity, which is impacted by the mutual interference of visual perception of different DCT coefficients and the reverse DCT, was analyzed in this paper. Furthermore, the relation between hiding capacity and coefficients-chosen was given out in DCT domain hiding algorithm. A conclusion that there is no correlation between embedded position and robustness against compression of embedded information was put forward, and embedded capacity could be improved in reference to this conclusion. The experimental results show that this conclusion is correct even if the system is disturbed by noise.

Key words: information hiding, embedded capacity, frequency coefficient, compression invariance, Discrete Cosine Transform (DCT), inverse transformation