近年來由於虛擬實境技術越來越成熟，市面上已開始出現相關的應用及商品。但由於時間延遲或是眼睛接收的訊號與真實身體狀況不同步，而讓使用者產生頭暈的感覺。因此，目前的VR穿戴式裝置皆不適合長時間使用。
為了克服這個問題，本文提出以扭曲的平面影像產生出具沉浸效果類似虛擬實境。藉由一橢圓半球模型，將置於內球表面的圖像投射至影像平面上，並搭配內插法做為補償。使一般影像經過轉換後亦能產生全景環場的效果，進而使人有沉浸在虛擬世界中的感受。其中包含有兩個設計參數，分別是觀看距離以及橢圓半球彎曲程度。實驗以110公分、143公分、176公分三種觀看距離作為測試，以觀看者作為圓心，觀看距離作為半徑所得之圓弧作為曲面影像，並得出觀看距離及橢圓半球彎曲程度之間的關係。
實驗共分兩種，立體環境感知實驗以及主觀沉浸感受實驗。在立體環境感知實驗中，觀看距離為110公分時的深度誤差最小，其次為143公分，而176公分的深度誤差最大。然而在橫向誤差上卻是110公分誤差最大、143公分次之，176公分誤差最小。而在主觀沉浸感受實驗中，觀看者透過優劣排序的方式評估三種不同觀看距離下所產生之影像帶來的沉浸感及舒適感。實驗結果顯示110公分擁有最佳的沉浸感，但舒適感卻最差；143公分的沉浸感雖較110公分來得差，但舒適感卻大幅提升；而176公分所帶來的舒適感較143公分佳，但沉浸感卻是三個距離中最不強烈的。從實驗結果可得知，觀看距離越近，橢圓半球彎曲程度越大的情況下，觀看者的沉浸感受會越強烈；但對於影像的失真影響也較大，且對於觀看者觀看影像時所感受之舒適感也較差。

In recent years, as virtual reality technology has become more sophisticated, related applications and products have begun to appear on the market. However, because of the time delay or out of sync of the signal received by the eye with actual physical condition, the people will feel dizzy while using those products. Therefore, current VR wearable devices are not suitable for long-term use.
In order to overcome this problem, this paper proposes to generate similar virtual reality with immersive effect using a distorted plane image. The picture on the inner surface of a half ellipsoid is projected onto an image plane and is compensated with interpolation methods. As a result, a general image can be transformed to produce the panoramic effect and the users feel immersed in the virtual world. There are two parameters involved regarding the immersive effect, namely the viewing distance and the curved degree of the half ellipsoid. Three viewing distances of 110 cm, 143 cm, and 176 cm are applied in the experiments. Furthermore, taking the viewer as the center of the circle, the circular arc obtained as the radius is viewed as a curved image, and the relationship between the viewing distance and the degree of curvature of the elliptical hemisphere is obtained.
There are two kinds of experiments: the three-dimensional environment perception experiment and the subjective immersion experiment. For the three-dimensional environment perception experiment, the depth error when the viewing distance is 110 cm is the smallest, followed by 143 cm, and the depth error of 176 cm is the largest. However, in terms of lateral error, 110 cm viewing distance produces the largest error, 143 cm second, and 176 cm with the smallest error. For the subjective immersion experiment, the viewers’ assessment on the degrees of immersion and comfort caused by the images with those three different viewing distances were investigated. The experimental results show that 110 cm has the best immersion, but its comfort is the worst. The sense of immersion for 143 cm is worse than 110 cm, but the comfort is greatly improved. The sense of comfort for 176 cm is better than 143 cm, but its immersion is the weakest among those three viewing distances. From the experimental results, it can be found that the closer the viewing distance is, the greater the curved degree of the half ellipsoid and the stronger the immersive perception of the viewers become. Nevertheless, greater distortion of the image can be caused and the users may feel poor comfort while watching the image.

論文審定書 i
誌 謝 ii
摘　要 iii
Abstract……………………………………………………………………………….iv
目錄 vi
圖目錄 viii
表目錄 xi
第一章 緒論 1
1.1 研究動機與目的 1
1.2 研究方法與步驟 2
1.3 文獻回顧 4
1.4 本文架構 7
第二章 影像轉換 9
2.1橢圓半球模型 9
2.2座標轉換 11
2.3考慮觀看距離之映射 12
第三章 內插補償 17
3.1 常用於影像之內插法 17
3.1.1最近相鄰內插法 17
3.1.2雙線性內插法 18
3.1.3雙立方內插法 19
3.1.4常用內插法之比較 20
3.2 轉換後影像上內插 28
3.3 轉換回原影像上內插 31
3.4 兩種內插法之比較 34
第四章 參數設計 45
4.1觀看距離與橢圓半球深度之關係 45
4.2最佳觀看距離 46
4.3參數選定 47
第五章 實驗設計及實驗結果 48
5.1 實驗設備介紹 48
5.2 實驗計畫及步驟 48
5.2.1 立體環境感知實驗 49
5.2.2 主觀沉浸感受實驗 55
5.3 實驗結果之分析比較 62
第六章 結論與未來規劃 69
6.1結論 69
6.2未來規劃 69
參考文獻 71
附錄一 立體環境感知實驗結果 74
附錄二 t值表 77
附錄三 主觀沉浸感受實驗結果 78

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