電腦藝術畫的自動產生與其在資料隱藏及浮水印之應用

Abstract

在本論文中，我們研究了三種藝術影像的自動產生與相關資訊隱藏技術。這三種不同類型的藝術影像分別是不規則六邊形畫、重疊馬賽克畫，以及多尺寸馬賽克畫。在不規則六邊形畫中，我們找到了兩種可供資訊隱藏的屬性，分別是六邊形的兩頂點與其內部顏色。藉由調整此兩頂點的座標位置及修改六邊形的內部顏色，我們可將秘密資訊及浮水印隱藏於不規則六邊形畫之中，達到秘密訊息傳輸與版權保護之目的。在重疊馬賽克畫中，我們利用相鄰兩小圖之重疊程度來達到資訊隱藏的目的。藉由改變相鄰小圖重疊大小的技巧，我們可以隱藏0~7個位元於相鄰兩小圖的X及Y方向重疊關係之中。在多尺寸馬賽克畫中，我們利用大圖及小圖兩種尺寸的圖來達到藏入秘密訊息之目的，而相鄰兩圖間並不會有裂縫或重疊的情形發生。我們並透過實驗結果來證明這些方法的實用性

Three types of art images are created in this study, namely, irregular- hexagonal-tiled image, tile-overlapping mosaic image, and variable-sized mosaic image. Methods for automatic generation of these types of art images and data hiding in them are proposed. For irregular-hexagonal-tiled images, we find two features for information hiding, namely, two specific vertices and inner colors of tiles. We can hide secret messages and watermarks into images by adjusting the locations of the two specific vertices and modifying the inner colors of hexagons. The methods may be used for secret communication and copyright protection. For tile-overlapping mosaic images, we utilize the overlapping pixels of adjacent tile images to implement the data hiding work. We can hide zero to seven bits into a pair of tile images by changing the overlapping degrees of adjacent tile images. For variable-sized mosaic images, we utilize two sizes of tile images to implement the data hiding work. We hide data bits into the tile images by changing the sizes of them dynamically without creating overlapping areas in the resulting stego-image. Experimental results show the feasibility of the proposed methods and their applications for data hiding and watermarking.