在人機互動系統中，眼神凝視方向一直被視為一項能用以展示使用者目光和注意力的重要訊息。過往的研究裡，可接受的頭部姿勢判斷和瞳孔位置估算大多能在受限制的環境設定下達成。到目前為止，由於偵測的低精準度和頭戴式裝置造成的不便，都導致目前即時目光偵測的相關應用還是十分有限。同時，當臉部不是正面朝向裝置時，眼睛定位系統還無法準確地定位瞳孔中心。本文提出了兩種新方法以改善現有的目光追蹤技術，第一種方法使用了最新的RGBD設備Kinect v2來估測頭部運動以及目光的三維方向，提供較高精確度的偵測和高解析度的圖像。第二，採用一項最佳化瞳孔搜尋法來提高搜尋效率，顯著降低運算時間，因此，本論文提出結合頭部姿勢和瞳孔位置資訊的混合方法，實際提升目光辨識估測效能。

In human-computer interaction, gaze orientation is known as an important
and promising source of information to demonstrate the attention and
focus of users. Within previous research, satisfactory accuracy in head
pose and eye location estimation can be achieved mostly in constrained
settings. However, currently, real-time gaze orientation based applications
are still limited due to low-accuracy or inconvenience of associated head-
mounted devices. Also, in the presence of non-frontal faces, eye locators
are not adequate to accurately locate the center of the eyes. In this thesis,
two novel methods are proposed to improve the existing gaze tracking
techniques. The first method uses Kinect v2, one of the latest RGBD
devices, to estimate the 3D direction of the head movement and gaze.
Different from the previous devices such as Kinect v1 and web-camera, it
offers high-accuracy detections and high-resolution images. In the second,
a revised pupil search method with optimization is devised to increase the
efficiency of searching and so as to significantly minimize the calculation
time. Therefore, in this thesis, a hybrid scheme combining the head pose
and the eye location information is proposed to obtain the enhanced gaze
estimation.

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