人眼視覺系統的相關報告指出，以對數為基底的曲線較能符合韋伯•費希納定律，在這篇論文中，我們提出一個以對數為基礎的區域性對比強化演算法，並藉由區域性的資訊去動態調整對數曲線的曲率，另外，我們也設計了一個二階段流程去排除經常在區域演算法中產生的副作用―光暈現象，這使得最後輸出的結果不只能強化局部性的細節而且能減少光暈現象帶來的影響。

Study of contrast sensitivity of the human eye shows that logarithm curve obeys the Weber-Fechner law of just noticeable difference response in human perception. In this paper, we proposed a local contrast enhancement algorithm with logarithm based curve and adaptively change the curvature with local information. We also define two parameter to decide the level of contrast enhancement in the tone mapping procedure. For halo artifact which is
suffered from local operator, a two-stages procedure is designed to solve the problem. Although our system has more complexity than ordinary contrast enhancement
algorithm. The result preserve more characteristics in detail and sharper edges of objects. For natural image, our result shows better performance and avoid halo artifacts.

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