摘要 本篇論文主要是在設計一個新型的影像浮水印系統，其目的是為了保障著作權擁有者的權利，在設計上，我們所提出來的方法具有兩個重要的特點來滿足數位浮水印的功能需求並可應用在空間域、小波域以及離散餘弦轉換域之中。 第一個特點是讓影像著作權擁有者自行設定浮水印資料的第一道私密鑰匙，或稱為本系統的外碼。 第二個特點是在原始影像中依據資料的重要性，預先設定若干個浮水印資料的嵌入位置，再藉由反互斥或(XNOR)操作來選擇浮水印資料合適的嵌入位置之後，並將它重新排列與編碼，以產生浮水印資料第二道私密鑰匙，或稱為本系統的內碼。 結合以上兩個特點再經由程式驗證之後，可證明我們所提出的方法不僅具有很好的隱密性(影像品質)，且經由影像攻擊之後，仍具有很高的強韌性，另外在萃取浮水印時，不必藉由原始影像輔助即可完成。 Abstract In this paper, a novel watermarking system is proposed. Our main propose is to protect the copyright of owners. There are two important characteristics to satisfy with the function requirements of watermarking system. In addition, the spatial, DCT, and DWT domains are successfully applied. The first characteristic is to let the image owners set the first secure key by their own, i.e., the external code in this system. The second characteristic is to pre-set several embedded positions of watermarking data based on their significance in original image. After using an Exclusive-Nor (XNOR) operator to choose appropriate embedded positions of watermarking data, mapping, and encoding, the second secure key is generated, i.e., the internal code in this system. Combining the above two characteristics and verifying by programs, the proposed method is proved to have good imperceptibility. Furthermore, the proposed method has high robustness even through attacks, and we do not need the aid of original image to extract watermark.
