強度對分佈(intensity-pair distribution)是近年來針對影像對比增強的新研究方法。它除了能有效地增強對比之外,亦能使得對比增強後雜訊不至於被放大。在此演算法中留有相當多可提供使用者自行調整的參數。而在適當的參數設定下,強度對分佈演算法確實有著令人激賞的表現。但是目前此種演算法中,並無有效選擇參數的方法。本文提出了一有效的準則來選擇參數,使得此演算法的效果能夠有效地發揮,並且透過疊代的方式,使得參數選擇具有自動化的能力。Intensity-pair distribution was recently proposed to enhance the contrast of an image without noise amplification. There are several parameters left in that algorithm. With proper parameter combinations, the algorithm performs very well, but there is no effective method of parameter selection mentioned. In this paper, we proposed an effective criterion to decide proper parameters to maximize its performance. Automation of parameter selection can easily be done by iteratively using proposed algorithm.