植基於權重分佈之可適性伽瑪校正對比度增強方法

Adaptive Gamma Correction for Contrast Enhancement Based on Weighting Distribution

邱奕勝(Yi-Sheng Chiu)

指導教授 ： 黃士嘉

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2011年)

摘要

本論文提出了一個有效對比度增強的直方圖修改方法。在數位影像處理、電腦視覺與圖形辨識中，對比度增強扮演著一個很重要的角色。基於伽瑪校正與照度像素的機率分佈，我們提出了一個自動的轉換技術來改善陰暗影像的亮度。對於視頻增強而言，我們使用視頻流中每幀之間的時間相依資訊，來減少重新計算以所提出的影像增強方法為基礎之轉換曲線。實驗結果顯示出，經由與先前最先進方法所產生的增強影像相比較之下，所提出方法所產生的增強影像具有較高的影像品質。

關鍵字

對比度增強 ； 直方圖修改 ； 伽瑪校正 ； 直方圖等化

並列摘要

This thesis proposes an efficient histogram modification method for contrast enhancement, which plays a significant role in digital image processing, computer vision, and pattern recognition. We present an automatic transformation technique to improve the brightness of dimmed images based on the gamma correction and probability distribution of the luminance pixel. For video enhancement, we use the temporal information between each frame to reduce the re-computation of the transformation based on the proposed image enhancement method. Experimental results show that the proposed method produces enhanced images of comparable or higher quality than previous state-of-the-art methods.

並列關鍵字

Contrast Enhancement ； Histogram Modification ； Gamma Correction ； Histogram Equalization

參考文獻

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