臺灣博碩士論文加值系統

增強對比在影像處理應用中扮演非常重要的角色。雖然釵h加強對比的方法已經被提出，但是這些方法在設計時都沒有注重在邊緣值的增強對比上。在本篇研究中，提出了索貝爾直方圖等化方法(Sobel histogram equalization, SHE)，可應用在增強對比處理上。使用SHE，利用索貝爾邊緣探測及本文提出的其他前處理方法，將影像被分割成2個部分，分別是邊緣部份(前景)，以及非邊緣(背景)部份2種。然後，再使用直方圖等化(HE)，對2部份各別作增強對比。在我們的實驗中，可以看出SHE在大部份情況下，在PSNR上的效果比其它方法還要優秀，另外也放上了處理影像的直方圖來比較本文與其他方法的效果。

Contrast enhancement is an important technique for image processing. Although many contrast enhancement methods had been proposed, these designed methods do not focus on the edge quality of image. In this study, the sobel histogram equalization (SHE) is proposed to enhance the contrast of image. In SHE, the image is divided into two regions, edge and non-edge, by using the sobel edge detector. The contrast of these two regions can be individually enhanced, and then these two regions can be merged into a whole image by the histogram equalization. In our experiments, SHE outperforms other methods.

目錄
中文摘要 ……………………………………………………………………………I
英文摘要 ……………………………………………………………………………II
誌謝 …………………………………………………………………………………III
目錄 …………………………………………………………………………………IV
表目錄 …………………………………………………………………………………V
圖目錄 …………………………………………………………………………………VI
第壹章　緒論 ……………………………………………………………………………1
1.1　研究動機………………………………………………………………………1
1.2　研究方向………………………………………………………………………2
1.3　相關研究………………………………………………………………………2
1.4　論文架構………………………………………………………………………3
第貳章　分離前景與背景 ……………………………………………………………4
2.1　方法架構………………………………………………………………………4
2.2 Sobel邊緣探測方法 …………………………………………………………5
2.3　動態門檻值二值化技術………………………………………………………9
2.4 二值影像補洞 ………………………………………………………………12
2.5 連接元件擷取技術去除雜訊 ………………………………………………15
2.6　分離前景與背景並進行形態學膨脹 ………………………………………19
第參章　增強影像對比…………………………………………………………………22
3.1 傳統的直方圖等化原理 ……………………………………………………22
3.2 將分離後的前景與背景進行增強對比 ……………………………………26
第肆章　實驗結果………………………………………………………………………28
第伍章　結論及未來研究方向…………………………………………………………89
參考文獻…………………………………………………………………………………90

參考文獻

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