Visual secret sharing (VSS) is a new technique for sharing a binary image into multiple shadows. For VSS, the original image can be reconstructed from the shadows in any qualified set, but cannot be reconstructed from those in any forbidden set. In most traditional VSS schemes, the shadows held by participants have the same importance. However, in practice, a certain number of shadows are given a higher importance due to the privileges of their owners. In this article, a novel ( t , s , k , n )-threshold VSS scheme is proposed based on access structure partition. First, we construct the basis matrix of the proposed ( t , s , k , n )-threshold VSS scheme by utilizing a new access structure partition method and sub-access structure merging method. Then, the secret image is shared by the basis matrix as n shadows, which are divided into s essential shadows and n - s non-essential shadows. To reconstruct the secret image, k or more shadows should be collected, which include at least t essential shadows; otherwise, no information about the secret image can be obtained. Compared with related schemes, our scheme achieves a smaller shadow size and a higher visual quality of the reconstructed image. Theoretical analysis and experiments indicate the effectiveness of the proposed scheme.

中文翻译：

---

一种新颖的( t , s , k , n )-基于访问结构分区的阈值视觉秘密共享方案

视觉秘密共享 (VSS) 是一种将二值图像共享为多个阴影的新技术。对于VSS，原始图像可以从任何合格集中的阴影中重建，但不能从任何禁止集中的阴影重建。在大多数传统的 VSS 方案中，参与者持有的影子具有相同的重要性。然而，在实践中，由于其所有者的特权，一定数量的影子被赋予了更高的重要性。在这篇文章中，一部小说（吨,s,ķ,n)-阈值VSS方案是基于访问结构划分提出的。首先，我们构建所提出的（吨,s,ķ,n)-阈值VSS方案，利用新的访问结构划分方法和子访问结构合并方法。然后，秘密图像被基矩阵共享为n阴影，分为s基本阴影和n-s非必要的阴影。为了重建秘密图像，ķ应收集或更多阴影，其中至少包括吨基本阴影；否则，无法获得有关秘密图像的信息。与相关方案相比，我们的方案实现了更小的阴影尺寸和更高的重建图像视觉质量。理论分析和实验表明了所提方案的有效性。