臺灣博碩士論文加值系統

影像增強常常是被討論的議題，其最主要的目的是為了改善影像的品質、可視度以及增加想要表達的細節。本研究最主要的目的就是將曝光度過高或是過低曝光影像中的可視度修正到較佳的結果。在傳統gamma 校正中，參數γ是由使用者手動輸入，所以許多的作者紛紛提出針對參數γ如何選出最佳的結果。
在本論文中，我們提出了對比增強、銳化增強和色彩增強，來改善影像的品質。在影像中的每一個區塊都具有屬於自己的亮度，因此我們提出了一個區域增強的方法計算出gamma 校正中參數γ的理想值，並以RGB色彩模型為雛形設計了一個演算法。

The main object of the image enhancement is increasing quality and visibility in the image. In the thesis, we proposed a simple and effective color enhancement method for the local approach that improved some quality and visibility for the low-exposure and high-exposure image. In the traditional gamma correction, the gamma parameter γis set by user. So many method have been proposed to determine the gamma parameter γ. We are interested in resolving this problem.
In this thesis, we proposed the contrast enhancement, sharpness enhancement and color enhancement. As we know, each block of the image that has their luminance. In this ideal, we proposed the adaptive gamma correction by using the local approach and using the RGB color model to design a simple color enhancement method.

論文口試委員會審定書 i
中文摘要 ii
ABSTRACT iii
誌謝 iv
表目錄 vii
圖目錄 viii
第一章 緒論 1
1.1 研究背景 1
1.2 研究動機與目的 2
1.3 論文架構 3
第二章 文獻探討 4
2.1 影像增強(Image enhancement) 4
2.1.1 Gamma校正 4
2.1.2 直方圖等化 7
2.1.3 重疊處理 13
2.1.4 其他有關直方圖等化與gamma校正之演算法 16
2.2 分群演算法 21
2.2.1 K-Means 21
2.2.2 Fuzzy C-Means 23
2.2.3 Otsu method 24
第三章 提出的方法 26
3.1 對比增強(Contrast enhancement) 26
3.1.1 直方圖修改 27
3.1.2 適應性的Gamma校正 31
3.2 銳化增強(Sharpness enhancement) 39
3.3色彩增強(Color enhancement) 41
第四章 實驗結果 45
4.1主觀分析 46
4.2客觀分析 55
第五章 結論與未來展望 57
5.1結論 57
5.2未來展望 57
參考文獻 59

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