近幾年搭載著深度感測器的攝影機是一種趨勢。在傳統只有顏色的影像上加入了深度資訊，使得互動式應用程式的發展得以更加卓越。這種由彩色感測器與深度感測器結合而成的RGB-Depth攝影機，如果要有效地結合深度資訊於彩色影像上，攝影機校正是必須實行的一個措施。本論文提出了一種基於直接線性轉換(Direct Linear Transformation)演算法的校正方法。直接線性轉換的優勢在於免去傳統校正方法所需要的繁瑣校正過程，利用物體與圖像上的線性關係來獲得攝影機參數，進而計算彩色攝影機與深度攝影機之間的關係，這關係包含了旋轉矩陣與位移向量。最後利用取得的參數來進行彩色幀(RGB frames)與深度幀(depth frames)的對齊，完成校正。而實驗結果表明了我們的方法是可行的，在未來我們將考慮鏡頭畸變來使得我們的校正方法更加精確。

In recent years, cameras equipped with depth sensors is a trend. The depth information makes the development of interactive applications further excellent. To make this kind of RGB-Depth cameras consisting of RGB sensors and depth sensors more concise, calibration is a must. This paper presents a novel calibration method based on the Direct Linear Transformation (DLT). The advantage of the DLT method is to get rid of the complicated calibrating procedures in the traditional calibration methods. The DLT method employs the linear relationship between objects and images to get camera parameters and measure the relationship between the RGB camera and the depth camera. The relationship contains the rotation matrix and the translation vector. Finally, we employ the acquired parameters to conduct the alignment of the RGB frames and the depth frames. The results of our experiments show that the proposed calibration method is practical. In the future, we will further consider the lens distortion and try to make the calibration more precise.

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