Recently, Li et al. proposed a data hiding method based on pixel value ordering (PVO) and prediction error expansion (PEE). In their method, maximum and minimum values were predicted and the pixel values were modified to embed secret data. Thereafter, many scholars have proposed improvisations to the original PVO method. In this paper, a Reversible data hiding (RDH) method is proposed where the secret data is dispersed into two layers using different modes of operations. The second layer changes the dividing mode, and the first and the second layers do not take duplicate blocks. Under a fixed embedding capacity, threshold value and block size are controlled, complex blocks are filtered and the secret data is hidden in smooth blocks. This paper also compares the effectiveness of four well-known PVO series methods, the latest PVO methods, difference expansion (DE) method and reduced difference expansion (RDE) method. Experimental results show that the proposed method reduces distortion in the image, thereby enhancing the visual symmetry/quality compared to previous state-of-the-art methods and increasing its high application value.

中文翻译：

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基于 PVO 的可逆数据隐藏利用两层嵌入来提高图像保真度

最近，李等人。提出了一种基于像素值排序（PVO）和预测误差扩展（PEE）的数据隐藏方法。在他们的方法中，预测了最大值和最小值，并修改了像素值以嵌入秘密数据。此后，许多学者提出了对原始 PVO 方法的即兴创作。在本文中，提出了一种可逆数据隐藏 (RDH) 方法，其中使用不同的操作模式将秘密数据分散到两层中。第二层改变划分方式，第一层和第二层不取重复块。在固定嵌入容量下，控制阈值和块大小，过滤复杂块并将秘密数据隐藏在平滑块中。本文还比较了四种著名的 PVO 系列方法的有效性，最新的 PVO 方法，差分扩展 (DE) 方法和缩减差分扩展 (RDE) 方法。实验结果表明，所提出的方法减少了图像中的失真，从而与以前最先进的方法相比提高了视觉对称性/质量，并增加了其较高的应用价值。