應用改良後的彩色直方圖等化方法於醫療影像增強上

Medical Image Enhancement Using Modified Color Histogram Equalization

周敬堯(Ching-Yao Chou)

指導教授 ： 許巍嚴

國立中正大學/管理學院/資訊管理系醫療資訊管理研究所/碩士(2015年)

摘要

影像強化(image enhancement)在醫學影像上是一極為重要的應用。而直方圖等化(histogram equalization)則是一種增強影像對比的影像強化法，它已成為一般或醫學影像處理中重要一部分，而被廣泛的研究與應用。然而，傳統直方圖等化方法沒有考慮色相保留(hue preserving)而導致影像強化後結果很差。因此，本研究提出了新的考慮到色相保留的彩色直方圖等化方法來解決傳統方法的缺失，同時希望能利用Gabor濾波器(Gabor filter)來對於影像細節部分做更好的增強，已呈現出更清楚的影像。本研究將所提出的方法與其它先前所提出的方法做比較，結果顯示本研究提出的方法在色相保留方面都比傳統方法來的好。最後，本研究將所提出的方法應用在視網膜影像以及前列腺癌細胞影像上，來獲取更為清楚的影像，其希望能有效的協助專業醫療人員進行專業判斷。

關鍵字

色相保留 ； 直方圖等化法 ； 影像增強 ； Gabor濾波器

並列摘要

Image enhancement represents a crucial application in medical imaging. Histogram equalization is one of the image enhancement techniques employed to enhance image contrast, which has become an vital part of general and medical image processing, and has been widely studied and applied. However, traditional histogram equalization achieves poor image enhancement results because it does not consider hue preservation. This study proposes a novel image enhancement method that incorporates hue preservation to address the problem of unpreserved hue in traditional approaches. In addition, this study use the Gabor filter to enhance image details. The results indicated that both methods achieved satisfactory results. Finally, this study proposed methods are applied to retinal and prostate cancer images. This can effectively assist physicians in making professional judgment.

並列關鍵字

Hue preservation ； Histogram equalization ； Image enhancement ； Gabor filter

參考文獻

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