最低位元置換法是偽裝學中一種簡單且容易實作的方法，此法存在著安全性與不可察覺性的問題，因此有學者提出最佳置換矩陣的概念，以提升最低位元置換法的安全性與不可察覺性。然而，過去學者在建構最佳置換矩陣時，皆未將人類視覺系統的特性納入考慮，因此本論文提出一套依人類視覺系統的特性建構最佳置換矩陣的方法，使得本論文所產生的偽裝影像，就人類視覺系統而言，更接近原始的掩蓋影像；另外，本論文亦設計了一種方式，使偽裝影像的的像素值盡可能地接近掩蓋影像。本論文的實驗結果顯示，偽裝影像的品質，不論是以人類視覺系統的指標衡量，或是以像素差異的指標衡量，皆優於其他學者的研究。
The Least significant bit(LSB) substitution for steganography is a simple and easy to implement method, but its major problems are security and imperceptibility. Some researchers proposed the concept of the optimal substitution matrix to improve the se-curity and imperceptibility of the LSB substitution. However, those researchers did not consider the properties of the human visual system when constructing the matrix. The aim of this researcher is to construct an optimal substitution matrix based on the human visual system, so that the stego-image looks like the cover-image in terms of the human visual system. In addition, the way of embedding the secret can make the difference between the stego-image and the cover-image be as closed as possible. Finally, we measure the stego-image quality according to two measurerrents SSIM and PSNR. The experiment results show that the image quality of our stego-image performs better than those of other researchers
