Image steganography, defined as the practice of concealing information within another image, traditionally encounters security challenges when its methods become publicly known or are under attack. To address this, a novel private key-based image steganography technique has been introduced. This approach ensures the security of the hidden information, as access requires a corresponding private key, regardless of the public knowledge of the steganography method. Experimental evidence has been presented, demonstrating the effectiveness of our method and showcasing its real-world applicability. Furthermore, a critical challenge in the invertible image steganography process has been identified by us: the transfer of non-essential, or `garbage', information from the secret to the host pipeline. To tackle this issue, the decay weight has been introduced to control the information transfer, effectively filtering out irrelevant data and enhancing the performance of image steganography. The code for this technique is publicly accessible at https://github.com/yanghangAI/DKiS, and a practical demonstration can be found at http://yanghang.site/hidekey.

翻译：图像隐写术被定义为将信息隐藏于另一图像中的实践。当隐写方法公开或被攻击时，传统隐写术常面临安全挑战。为此，我们提出了一种新颖的基于私钥的图像隐写技术。该方法可确保隐藏信息的安全性——无论隐写方法是否公开，访问隐写信息均需对应的私钥。我们提供了实验证据，验证了该方法的有效性并展示了其实际应用价值。此外，我们识别出可逆图像隐写过程中的一个关键挑战：从秘密图像到宿主管道的非必要信息（即"垃圾"信息）转移。为解决此问题，我们引入衰减权重控制信息转移，有效滤除无关数据并提升图像隐写性能。该技术的代码已公开于 https://github.com/yanghangAI/DKiS，实际演示可访问 http://yanghang.site/hidekey。