以擴增實境輔助電影拍攝 - 綠幕合成之應用

Abstract

近年來，電影特效的合成越來越普及，電影公司大量的使用綠幕影像的合成來創作。這類的技術需要非常專業的器材輔助，例如機械手臂、吊臂與滑軌等等。主要目的是為了讓兩段要合成的影片之運鏡能夠相同，如此才能順利結合而不產生變形或視差等等的破綻。是一件相當精細且困難的任務。然而，這類專業器材的價格相當昂貴，動則數十萬甚至百萬，對於學生或是一般獨立製片是相當昂貴的負擔。因此，我們使用擴增實境之導引來取代上述器材，讓使用者藉由手持相機及擴增實境之導引進行拍攝。同時也實作了軟體影像穩定之演算法來修正由手持相機所造成之晃動與位移。以低成本之系統設計達到相似的效果。

Creating videos from compositing multiple footages requires the support of the robotic arm due to the camera motion model needs to be precise. It is extremely difficult to shoot the footage with a hand-held camera. However, the cost of the robotic arm is extremely high. Thus, we introduce an augmented reality guiding system to replace it. In our system, we utilized augmented reality to guide the user for the camera motion and implemented an algorithm of stabilization and camera motion alignment for a hand-held camera. The system reduces the cost but remaining good quality of the result at the same time.