以影像為基礎的成像系統(IBR)常常應用於各種虛擬實境與電腦繪圖中，並且提供一個栩栩如生的環境，讓人們可以在其中自由行走，但是卻因為沒有模型或是三維空間的概念，使得我們無法在IBR系統中加入一些新的物件模型，如人物、家俱等等，這種限制對於虛擬會議系統或是室內設計等應用都是非常不利的，所以我們希望能夠有一個
方法，使得我們不但有照片般的畫質，更有模型所需要的三維資訊。
在這篇論文中，我們提出了一種以模型為基礎的的IBR系統，首先，我們使用多張全景影像，標出影像上垂直的牆角，進而建立出場景的牆面模型，在牆面的貼圖方面，我們將會考慮目前所在的虛擬位置，挑出適合的全景影像，並將此影像做適當的重取樣，得到沒有全景形變的各牆面材質，但因為有時場景太複雜，且重取樣的計算量過大，在成像時會有延遲的感覺，為了提昇移動時的frame rate，我也建立了一連串的判斷機制，如可調性的牆面材質，360度的可視牆面，與視角內牆面，以節省在成像時所要花的時間。另一方面，光源的影響在電腦繪圖中也是很重要的一環，在文章中，我們亦會討論光源的定位、顏色，點光源的衰減量，以改善在傳統的場景IBR裡，沒有光源訊息的問題，使物件加入場景後，有著正確的光影效果，這樣除了場景本身，就連裡面所外加的物件還有其他的人物等，也能有真實的效果。

Image-based rendering (IBR) is usually applied in the computer graphics and virtual reality and provides a photorealistic virtual environment in which the user can move around. However, because this method does not contain the concept of the model or 3D information, a new object such as a man or a piece of furniture can not be added to this system. This limitation is disadvantageous for virtual video conference or interior decoration.
In this thesis, a Model-based IBR system is proposed. First, several panoramic images are selected and the featured vertical edges are marked on these images. Then a basic model of the environment is constructed. When it comes to texture maps, the user’s location will be used to select a suitable panoramic image to be considered and this image will be remapped to display a texture without distortion. Nevertheless, sometimes the virtual world is so complex that the time for remapping is very long and time lag will occur in the process of rendering. In order to increase the display frame rate, several mechanisms are designed such as flexible resolution of the texture and visible walls. These methods will reduce the time for rendering. Besides, the lighting effect is another important topic in the computer graphics. In the thesis, the location and the color of light and decay of a point light source will be discussed in order to improve the defect that shows no lighting information about the environment in traditional Image-based rendering. Thus, a realistic virtual world which can add a new object with good lighting effects is developed.

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