利用畫面空間重要性在作用介質中的梅特羅波利斯光源傳輸演算法

Metropolis Light Transport with Screen Space Importance in Participating Media

連俊豪(Chun-Hao Lien)

指導教授 ： 施仁忠

國立交通大學/資訊學院/多媒體工程研究所/碩士(2019年)

摘要

光線追蹤是計算出擬真影像的常見手段。在光線追蹤演算法中，主要分成了兩大類：基於路徑和基於光子的光線追蹤，但以上兩類方法都有他們適合及不適合的場景。
UPBP 演算法利用兩類多種演算法及多種重要性採樣來平衡估測誤差，雖然可以做到很好的效果但缺點就是計算量龐大。

我們提出一種簡單的指標來引導光線追蹤，會考慮成像到場景和場景到成像兩邊的重要性作估計，並利用突變光線路徑的方式逼近原始模型。讓追蹤過程中，對最終成像有更多貢獻潛力的場景位置採樣，進而提高原演算法的效率。

關鍵字

計算機圖學 ； 光線追蹤

並列摘要

Ray-tracing is the essential way to render a photorealistic image and there are two kinds of algorithm to integrate global illumination problem: path-based and photon-based methods. The UPBP method uses both kinds of algorithm and combines with multiple importance to reduce the error of estimation. They can render very good results but need lots of time.

We'll introduce a simple way to hint light tracers. The Screen Space Importance will consider the weight from scene to screen and vise versa, and mutate the light path to approximate ground truth. The SSI can samples the scene area which has more potential to contribute final image, to make the UPBP rendering method more efficient.

並列關鍵字

Computer Graphics ； Ray-tracing

參考文獻

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