Prior to the publication of our article in 2018, to our knowledge, there were no methods of achieving a favourable trade-off between the payload in bits-per-pixel (bpp) and the quality of the reconstructed image in terms of PSNR or SSIM. Indeed, a high payload value would lead to a degradation of the reconstructed image’s quality. Moreover, it should also be noted that almost all of the other state-of-the-art methods at the time, were based on Least Significant Bit (LSB) substitution and made little use of the redundancy between pixels in the clear domain to realize the data embedding of a secret message. In our proposed work [2] , we have taken the opposing view by developing a Most Significant Bits (MSB) prediction-based reversible data hiding in encrypted images (RDHEI) method. In the EPE-HCRDH approach, the original image is encrypted without modification and information about the location of all pixels which cannot be correctly predicted is embedded by MSB substitution. In order to localize the prediction errors, flags of consecutive bits equal to 1 are used. With this information, the data hider can detect all the bits which can be marked and substitute them with bits of a secret message. In this case, the payload is slightly lower than 1 bpp, but perfect reversibility is achieved. So, the proposed EPE-HCRDH approach provides a high payload with a little complexity. But as highlighted by Dragoi and Coltuc [1] , the fact of using flags, so that the data hider can embed a secret message introduces security flaws in the method. Despite this, the method has attracted the attention of many researchers, with 100 citations (according to Google Scholar on November 9, 2020) in several peer-reviewed journals of excellent reputation (IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY [3] , IEEE TRANSACTIONS ON MULTIMEDIA [4] – [7] , IEEE ACCESS [8] , IEEE TRANSACTIONS ON SIGNAL PROCESSING, and IEEE TRANSACTION ON DEPENDABLE AND SECURE COMPUTING [9] . Today, we can say that high capacity RDHEI has become a hot topic.

中文翻译：

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反驳：关于通过MSB预测隐藏在加密图像中的可逆数据的安全性

在2018年发表文章之前，据我们所知，尚无方法在PSNR或SSIM方面的有效载荷/像素（bpp）与重构图像的质量之间取得良好的折衷。实际上，高有效载荷值将导致重建图像的质量下降。此外，还应该注意的是，当时几乎所有其他最新技术都是基于最低有效位（LSB）替换的，很少利用明域中像素之间的冗余来实现秘密消息的数据嵌入。在我们的拟议工作中[2] ，我们通过开发隐藏在加密图像中的基于最高有效位（MSB）预测的可逆数据（RDHEI）方法采取了相反的观点。在EPE-HCRDH方法中，原始图像未经修改就被加密，并且有关无法正确预测的所有像素位置的信息通过MSB替换嵌入。为了定位预测误差，使用等于1的连续比特的标志。借助此信息，数据隐藏器可以检测所有可以标记的位，并用秘密消息的位替换它们。在这种情况下，有效负载会略低于1 bpp，但可实现完美的可逆性。因此，所提出的EPE-HCRDH方法提供了高负载，并且复杂度很小。但正如Dragoi和Coltuc所强调的那样[1] 使用标记的事实，以便数据隐藏器可以嵌入秘密消息，从而在该方法中引入了安全漏洞。尽管如此，该方法仍吸引了许多研究人员的注意力，在几篇同行好评的期刊中（视频技术的电路和系统的IEEE交易）被100次引用（根据2020年11月9日的Google Scholar）。[3] ，IEEE多媒体交易 [4] – [7] ，IEEE访问 [8] ，有关信号处理的IEEE事务以及有关可靠和安全计算的IEEE事务 [9] 。今天，可以说高容量RDHEI已成为热门话题。