隨著網路流通的便利性與多媒體資訊的快速發展。使得數位影像可以輕易的被擷取，並利用現存的影像處理軟體進行竄改或是破壞，因而數位影像的安全機制保護變成一個重要的課題。本篇論文針對數位影像提出一個可進行竄改偵測及自我回復的浮水印機制。在竄改偵測上，本研究引用Hsu和Tu的方法，在影像中藏入驗證訊息，做為檢測與定位影像遭受竄改之處，而在回復影像方面，本研究利用Shamir的秘密分享的概念將影像區塊的回復訊息產生三份，並分散地藏在不同的區塊中，當確認影像區塊遭受竄改時，只要取回其中的兩份便可重建回復訊息，並以此回復訊息來修補影像區塊。
Digital images are easy to be modified and distributed; hence many researchers were devoted to the study of image authentication. Except for tampering detection, some researchers proposed methods to recover tampered images. The aim of this research is to propose a recovery scheme for tampered images. Our scheme employs Shamir’s threshold secret sharing scheme to split the recovery message into three shares, and gathering any two of the three shares can reconstruct the recovery message. As regards to image authentication, we utilize Hsu and Tu’s scheme, which has a low error rate in tampering detection.
