Web3D是3D/VR技術在網際網路上一個應用領域。然而受限於頻寬的限制，無法在Web3D中提供高解析度的貼圖效果，僅以低解析度壓縮影像貼圖或高解析度重複拼貼技術相互運用來滿足視覺上的需求。很幸運地，近年來紋理合成的技術成為熱門的研究領域，而這方面研究最早的動機正是解決重複拼貼貼圖技術的問題，以紋理合成的方式產生高解析度影像。本研究主要應用patch-based sampling紋理合成法於Web3D的大面積貼圖上，改變以往在Web3D中使用重覆拼接貼圖技術的缺點，並以旋轉紋理塊面的方式得到更加隨機性的改良結果。我們也將研究的結果與原本的patch-based sampling作比較，藉由傅利葉頻譜的分析，證明旋轉後的結果具有更加隨機性。雖然這個方法只適用於隨機性紋理，但是它能使紋理產生創新的變化效果，未來更可應用於紋理或圖案的設計。

The purpose of this study is to apply a Rotating Patch-based Texture Synthesis (RPBS) methodology to Web3D large-scale landscape graphics design. It solves the problem of Web3D landscapes needing large textures to construct a flexible surface. RPBS improves Patch-Based Sampling (PBS). To compare these two methods, the Fourier spectrum analysis was used to extract the directionality properties of these textures. This was done by using Principle Component Analysis (PCA), which reveals the ratio of the characteristics' values. It was concluded that texture changes of the RPBS synthesis lead to images with better visual effects, which are more suitable for flexible texture applications; whereas PBS works better in structural texture applications. Additionally, it was found that, despite the limited size of the pixels (64 x 64), using RPBS yields a better quality product compared to that of PBS in terms of having a lower re-selection frequency as well as better matching of the overlapping edges. Finally, it was proposed to use RPBS calculation and the instant synthesis methods in the Web3D applications. The instant synthesis method enables the completion of the expected results quickly, which makes it more suitable for the Web3D application. In the future, it is likely that RPBS will be applied to other 3D/VR fields, such as 3D geology information systems and 3D web-based games, etc.

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