This short paper proposes to use the statistical analysis of the correlation between DCT coefficients to design a new synchronization strategy that can be used for cost-based steganographic schemes in the JPEG domain. First, an analysis is performed on the covariance matrix of DCT coefficients of neighboring blocks after a development similar to the one used to generate BossBase. This analysis exhibits groups of uncorrelated coefficients: 4 groups per block and 2 groups of uncorrelated diagonal neighbors together with groups of mutually correlated coefficients groups of 6 coefficients per blocs and 8 coefficients between 2 adjacent blocks. Using the uncorrelated groups, an embedding scheme can be designed using only 8 disjoint lattices. The cost map for each lattice is updated firstly by using an implicit underlying Gaussian distribution with a variance directly computed from the embedding costs, and secondly by deriving conditional distributions from multivariate distributions. The covariance matrix of these distributions takes into account both the correlations exhibited by the analysis of the covariance matrix and the variance derived from the cost. This synchronization scheme enables to obtain a gain of PE of 5% at QF 95 for an embedding rate close to 0.3 bnzac coefficient using DCTR feature sets.

中文翻译：

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JPEG 隐写术和给定开发管道的 DCT 系数同步

这篇短文提出使用 DCT 系数之间相关性的统计分析来设计一种新的同步策略，该策略可用于 JPEG 域中基于成本的隐写方案。首先，在类似于用于生成 BossBase 的开发之后，对相邻块的 DCT 系数的协方差矩阵进行分析。该分析展示了不相关系数组：每块 4 组和 2 组不相关的对角邻居以及相互相关的系数组，每组 6 个系数和 2 个相邻块之间的 8 个系数。使用不相关的组，可以仅使用 8 个不相交的格子来设计嵌入方案。每个格子的成本图首先通过使用隐式底层高斯分布更新，其方差直接从嵌入成本中计算出来，其次通过从多元分布中导出条件分布。这些分布的协方差矩阵既考虑了协方差矩阵分析所显示的相关性，也考虑了成本得出的方差。对于使用 DCTR 特征集的接近 0.3 bnzac 系数的嵌入率，这种同步方案能够在 QF 95 下获得 5% 的 PE 增益。这些分布的协方差矩阵既考虑了协方差矩阵分析所显示的相关性，也考虑了成本得出的方差。对于使用 DCTR 特征集的接近 0.3 bnzac 系数的嵌入率，这种同步方案能够在 QF 95 下获得 5% 的 PE 增益。这些分布的协方差矩阵既考虑了协方差矩阵分析所显示的相关性，也考虑了成本得出的方差。对于使用 DCTR 特征集的接近 0.3 bnzac 系数的嵌入率，这种同步方案能够在 QF 95 下获得 5% 的 PE 增益。