現今多媒體影音裝置與人類生活息息相關，而其中顯示器的解析度與影像品質有大幅度的改善。雖然影像品質改善良多使得人眼所感受到的視覺品質提升，但其中所消耗的功率也大幅提升，因此顯示器的功率消耗變成一個不可忽視的問題。為了取得顯示器之間功率與影像品質的最佳平衡，我們提出一種在有機發光二極體顯示器上利用直方圖調整的演算法來達到功率節省與影像對比強化的效果。這個演算法使用一種前處理來修改直方圖藉此達到降低功率消耗的目的，並且利用功率節省直方圖等化的效果來補償影像對比。由實驗數據可知，我們所提出的演算法相對於其他演算法不僅能夠降低功率消耗並且能產生出高品質的影像對比。

For the modern multimedia devices,
display resolution and image quality are actively improved in nowadays.
Although the aforesaid improvement can produce the high visual perception for the observer,
the power consumption becomes an inevasible problem as it is rising progressively.
In order to get a good balance between visual perception and power consumption,
we propose a histogram-based power saving algorithm to improve the image contrast for the OLED display panel.
The proposed algorithm modifies the image histogram as a pre-process of power reduction.
Furthermore, the visual effect is compensated using the power saving histogram equalization algorithm.
Experimental results show that the proposed algorithm not only decreases the display power lower than that by the compared algorithm,
but also generates the highly perceptual contrast of the images.

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