在本篇論文中，我們提出用於三維關鍵影格動畫之強健型盲式浮水印演算法以達到著作權保護的目的。本演算法首先由關鍵影格動畫中擷取出三維模型，接著以模型中各點間表面距離為估算基礎，將其分割成數個不受模型本身姿勢改變而影響的重要特徵區塊。然後根據各點與切割邊界的表面距離進一步將此特徵區塊分成許多不重疊的集合。再者，我們基於表面粗糙度來調整各個集合的平均表面距離以嵌入版權浮水印。最後，將此已嵌入浮水印的模型資訊反映於原出處，以獲得一個具有版權資訊浮水印的三維關鍵影格動畫。實驗結果證明所提出的演算法具有抵抗常見用於三維動畫之攻擊的能力，其中包括時間軸攻擊、姿勢改變，相似轉換，頂點重新排列，局部性變形，切割，簡化、隨機雜訊添加，表面平滑化等攻擊。

A novel robust blind watermarking algorithm for three-dimensional (3D) keyframe animation is proposed in this thesis for copyright protection. In this algorithm, the geodesic distance of each vertex pair on the 3D mesh model extracted from a 3D keyframe animation to be watermarked is calculated, and then this model is segmented into meaningful pose-invariant components based on the calculation result. Each meaningful component is further divided into non-overlapping cells according to the distribution of geodesic distances from its vertices to the cutting boundary. Moreover, the defined watermark is embedded into these cells by adjusting the mean value of geodesic distances according to surface roughness estimation. Finally, we insert this watermarked model to the original animation content to obtain a watermarked 3D keyframe animation. Our experimental results demonstrate that the proposed algorithm has the ability to resist the common attacks applied to the 3D animation content, these attacks include timeline attacks, pose changing, similarity transformations, vertex reordering, local deformation, cropping, simplification, additive random noise, and smoothing.

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