臺灣博碩士論文加值系統

電腦斷層掃描技術應用在生活中許多領域，而電腦斷層掃描器的發明是將其實作出來。依照不同類型物體作掃描，發展出不同的掃描器。在電腦斷層影像的重建技術中，影響重建結果的品質有許多原因，所以要如何提升影像品質是重要的。

本論文主要實作一個電腦斷層掃描器系統，並加入一些可控制因素，這些因素現實上會造成重建影像的artifact。本系統除了模擬產生的artifact外，能提供方便驗證解的途徑，來驗證能減少重建後artifact產生的方法是否成功，而不需要實際操作掃描器去驗證。我們使用直接立體渲染法中，texture-based立體渲染法來實作我們的系統，並運用三維空間的座標轉換實作各個控制因素，達到擬真的掃描系統。

Computerized Tomography (CT) be applied in many fields, and it is implemented by the investion of computerized tomography scanner. According to different types of scanning objects, we developed different kinds of scanners. There are several facts that affect the quality of the results of reconstruction in the scope of CT image reconstruction method, and the image enhancement is important.
In this thesis, we bulid a CT scanner system with some configurable factors for the artifact construction, which would occur in reality. The system in this thesis not only simulates the artifact by some configuable factors, but also provides a solution for other verification methods to verify the quilty of the results of CT reconstruction without the requirement of the real CT scanner.
This study implement texture-based volume rendering technique to build the system, due to texture-based method is well-known in the scope of direct volume rendering. In addition, the study utilized three dimention geometry transformations to implement the configurable factors. These techniques make the system to be realism.

第一章 序 論 1
第二章 相關背景與理論基礎 3
2.1前言 3
2.2影像重建理論基礎 3
2.3重建演算法 4
2.4 CT掃描器的演進 6
2.5三維顯示技術 10
2.6著色器 14
第三章 實作方法 15
3.1鏡頭與物體的相對關係 15
3.2視點位置計算 16
3.3 3D texture-based volume rendering 21
3.4 2D texture mapping 24
第四章 實作與成果 25
4.1系統介紹 25
4.2 CT影像重建的流程圖 26
4.3 實驗成果 28
第五章 結論與未來展望 59
參考文獻 60

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