可見光眼動儀的核心技術是在眼睛影像中框取虹膜輪廓。系統的計算複雜度源自於分析眼睛圖像中可能呈現的不同虹膜形狀和不同照明條件下的影像。本論文中提出三個方法：一、眼球模型建構方法和改進的虹膜匹配方程式，藉此提高系統精準度和精密度。二、階層式搜尋用於即時的眼球模型與眼睛影像的匹配。三、在多核心微處理器上，本系統實現了高精密度的平行化凝視點估計系統架構。實驗結果改善眼球模型建構明顯提升了眼球模型匹配的精密度、階層式搜尋可以快速地在眼睛影像中匹配出虹膜並估計眼球旋轉角與所提出的平行化系統架構可以用於眼動儀系統當中並實現計算高於4000幀/秒的速度。

The core technology of visible-spectrum gaze tracker (VSGT) is the determination of the limbus circle on the eye image. The high complexity of analyzing eye images comes from various projection shapes of the eyeball and illumination conditions. In this thesis, we proposed an eyeball model construction method and refined iris matching equation to improve the system accuracy and the precision. In addition, a parallel computing architecture incorporating with a hierarchical search scheme for real-time limbus circle matching has been presented. The experimental result shows that the proposed model construction method significantly improves the overall eyeball model matching performance. The proposed hierarchical search scheme efficiently determines the optimal match model for an input eye image, and the proposed parallel computing architecture could be applied to the design of a high speed VSGT with the frame rate higher than 4000 frames/s.

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