在本論文的研究中，我們提出以凌波 (wavelet) 為基礎的多重解析度地形模塑與貼圖。在多重解析度地形模塑方面，我們以凌波分解技術來製作出不同解析度的地形模型。同時配合貼圖的衛星影像也以另一種凌波分解技術來做同樣層次的多重解析度變化。另外配合大區域地形展示的需要，我們發展出動態載入的技術來配合凌波分解多重解析度地形展示。首先我們將整個地形模型分割成為許多較小的矩形地塊。在瀏覽時適時地載入我們所要呈現的地塊；而且每個地塊會根據觀察者到該地塊的距離來決定它該呈現的解析度。本研究的特色有下列幾點： (i) 凌波多重解析度模型會以內插近似的方式 (Interpolating approximation) 來逼近原始精密模型、 (ii) 凌波多重解析度模型與影像的資料不會擴大、 (iii) 我們以整數對整數的凌波分解技術來轉換影像，使得轉換資料完全保存、 及 (iv) 動態載入中不同解析度的相鄰地塊以完全模組化方式快速對應。

In this paper, techniques of multiresolution terrain modeling and texture mapping based on the wavelet mesh (WM) and wavelet image (WI) are proposed. The WM terrain modeling is also combined with a dynamic loading technique for browsing large terrains. At first, we partition a large terrain mesh into blocks. Then we dynamically load parts of those terrain blocks for browsing. Based on the distance to the viewer, the resolution of each terrain block is automatically adjusted. Additionally, several studies on this topic are also proposed, which are: (i) texture-mapping images with multiresolution form, (ii) adopting rounding technique to avoid loss of image data during wavelet transform, and (iii) solving the boundary matching problems for adjacent terrain blocks in dynamic loading. The proposed techniques are suitable for browsing large terrain models on PC platforms.

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