本研究提出一項全新的適用於印刷影像特性之資料隱藏技術，利用印刷半色調網點在色彩排列組成方式的不同來表現所隱藏的訊息，這種特殊組成型態的網點稱作是漩渦式網點（Vortex Dot），其微小型態上的變化不易被人眼所察覺。同時，本研究也設計了兩組數位影像特徵，分別是色彩力距（Color Moment）與相對色彩位移（Relative Color Displacement），用以檢驗彩色半色調印刷影像的網點組態變化。進一步再配合本研究所提出的方陣式位址碼（Phalanx Addressing Code）編碼技術在二維影像平面上進行與位置無關（Location Independent）的資料儲存與擷取，藉由隨機隱藏提高加密的安全性。實驗結果顯示本研究所提出的加密技術可在彩色半色調印刷影像中進行資訊隱藏，並且將輸出影像掃瞄後進行辨識解碼處理。

In this dissertation we propose a brand-new data hiding technique for color halftone printed images. The configuration of the color composition of a halftone cell is adopted to present the hidden information. Such a halftone cell with various composition configurations is called the vortex dot. The tiny variation of these cells is almost invisible for human being. In addition, we also design the two features, called the color moment and relative color displacement, to classify the configuration of the vortex dots. Besides, we further propose the phalanx addressing code, to encode the hidden data into the host image in a location-independent way. It could raise security of data hiding by embedding randomly. The experimental results show that the proposed method is a possible solution to hide data in a color halftone printed image.

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