在圖學的領域中，照明設計（lighting design）的目的是為了提供光源讓目標可視，並讓觀賞者更易於欣賞合成出的影像。然而，現存大部分的照明設計自動化皆是針對靜態模型的設計方法，鮮少針對動態模型，為此，我們提出一種針對動作資料（motion data）的照明設計自動化方法。

我們將動作資料之照明分為場景的「整體照明」和角色的「區域照明」兩部分。整體照明提供讓目標可視之基本光源，我們視動作資料於舞台上表演，以舞台照明設計之概念建構整體照明，根據動作資料的活動區域，加上採取「視點最大資訊量(viewpoint entropy)」決定舞台方向的觀念，可決定整體照明光源之相關參數；而區域照明之目的在於突顯角色，基於實務常使用之三點打光（three-point lighting）原則，觀察不同型態光源（主光、補光與背光）對角色所造成不同的影響，區域照明配置問題可轉換成數個不同的最佳化問題。配合動作資料根（root）關節軌跡所在的區域，可挑選出數張關鍵影格，對各關鍵影格完成區域照明後，配合適當的照明參數內插，便可達到動作資料之照明設計。文末將展示數個根據此法所產生合成影像的效果。

In computer graphics, lighting designs attempt to achieve desired visual goals and assist viewers to appreciate the synthesized images better. As most existing automatic lighting designs are mainly for static targets, in this paper we present a novel automatic lighting method for motion data. We divide our lighting design into “global lighting” for scenes and “local lighting” for characters. For global lighting, we propose a viewpoint entropy algorithm to determine its lighting parameters according to the acting area of the motion data. Then we show that the best placement of each local light could be obtained by solving the corresponding optimization problem. Note that key frames can be identified by observations of root’s trajectory of motion data. Finally, by appropriate interpolations of lighting parameters of each key frame, the goal of the lighting design for motion data could be achieved. Several examples are given to demonstrate the effectiveness of the proposed method.

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