Reversible Data Hiding (RDH) is a practical and efficient technique for information encryption. Among its methods, the Pixel-Value Ordering (PVO) algorithm and its variants primarily modify prediction errors to embed information. However, both the classic PVO and its improved versions, such as IPVO and PVO-k, share a common limitation: their maximum data embedding capacity for a given grayscale image is relatively low. This poses a challenge when large amounts of data need to be embedded into an image. In response to these issues, this paper proposes an improved design targeting the PVO-k algorithm. We have reconstructed the mapping scheme of the PVO-k algorithm to maximize the number of pixels that can embed encrypted information. Experimental validations show that our proposed scheme significantly surpasses previous algorithms in terms of the maximum data embedding capacity. For instance, when embedding information into a grayscale image of an airplane, our method's capacity exceeds that of PVO-k by 11,207 bits, PVO by 8,004 bits, and IPVO by 4,562 bits. The results demonstrate that our algorithm holds substantial advantages over existing methods and introduces innovative mapping ideas, laying a foundation for future research in reversible data hiding in images.

翻译：可逆数据隐藏（RDH）是一种实用高效的信息加密技术。其中，像素值排序（PVO）算法及其变体主要通过修改预测误差来嵌入信息。然而，经典PVO算法及其改进版本（如IPVO和PVO-k）都存在一个共同的局限性：对于给定的灰度图像，其最大数据嵌入容量相对较低。当需要将大量数据嵌入图像时，这构成了一个挑战。针对这些问题，本文提出了一种针对PVO-k算法的改进设计。我们重构了PVO-k算法的映射方案，以最大化可嵌入加密信息的像素数量。实验验证表明，我们提出的方案在最大数据嵌入容量方面显著超越了先前算法。例如，在向飞机灰度图像中嵌入信息时，本方法的容量较PVO-k提高了11,207比特，较PVO提高了8,004比特，较IPVO提高了4,562比特。结果表明，本算法相较于现有方法具有显著优势，并引入了创新的映射思路，为未来图像可逆数据隐藏的研究奠定了基础。