本論文提出一套數位影像處理的方法，消除二維影像上的speckle noise以及灰階雜訊。這種speckle noise是以雷射光(高時間同調性光源)作為照明系統時所產生。另外，對光學檢測而言，以雷射光源作為檢測系統的訊號產生裝置，所產生的speckle noise對擷取得的訊號有莫大傷害，因此消除speckle noise有其必要。
消除雜訊的方法很多，例如Band-pass Filter、Enhanced Frost Filter、Gamma Filter、Enhanced Lee Filter等，但是均無法完全消除雜訊。其中，「經驗模態分解法」(Empirical Mode Decomposition,
EMD)能有效分析雜訊。然而EMD多應用於時間函數(電子訊號、聲音訊號)之訊號處理，對空間函數(尤其是含有雷射光斑的數位影像)之訊號處理尚無重大著墨。本論文為利用EMD來解決雷射光斑的問題，並且嘗試利用此項技術，應用於干涉條紋圖形的分析。

A novel method to reduce speckle noise from a digital image is presented. Speckle noise is introduced once a coherent light source is used. In this paper, we use the Empirical Mode Decomposition(EMD) method to remove speckles caused by such kind of coherent illumination. Many filter algorithms, such as Band-pass Filter, Enhanced Frost Filter, Gamma Filter, Enhanced Lee Filter, have been extensively studied to remove the speckle. However, they cannot remove noise effectively. The EMD method is able to analysis noise efficiently. This makes it possible to accurately analyze fringes in the frequency domain and to accurately retrieve the signal.

誌謝………………………………………………………Ⅰ
中文摘要…………………………………………………Ⅱ
英文摘要…………………………………………………Ⅲ
目錄………………………………………………………Ⅳ
圖目錄……………………………………………………Ⅵ

第一章 緒論
1-1 前言…………………………………………………1
1-2 研究動機與目標……………………………………4

第二章 經驗模態分解法的相關原理
2-1 簡介…………………………………………………5
2-2 內建模態函數的相關原理…………………………7
2-3 經驗模態分解法的原理……………………………9

第三章 實驗結果
3-1 前言………………………………………………16
3-2利用經驗模態分解法處理二維影像……………17
3-3 分析實驗簡介..……………………………………22
3-4 利用經驗模態分解法分析訊號與二維影像……24

第四章 結論………………………………………………66
參考文獻…………………………………………………67

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