以直方圖調整為基礎之直方圖等化方法是一種有效並且快速的對比度強化技術。然而，傳統的直方圖等化方法通常會在處裡過後的影像上出現過度的增強結果，因此輸出影像通常會在人們的視覺感官上呈現不自然的效果。
在本論文中，我們以自動分離直方圖為基礎，將所分離出的子直方圖分別做轉換，再將各個轉換後的片段方程式結合，因而提出了一個新的直方圖等化方法。我們將所提出的方法與傳統的HE、BBHE、DSIHE與RSIHE方法做品質與功率的比較。為了證明所提出的方法具有高品質的特性，我們先對各種方法所產生的圖片進行視覺與量化的分析，再比較各種方法在不同解析度中所測得的功率消耗。實驗結果顯示，本論文所提出的方法雖然會因為自動平均切割直方圖的機制而增加些微的功率消耗，但卻可以有效保持原始影像亮度和增加影像對比。

Histogram equalization is an effective technique for contrast enhancement. However, the traditional histogram equalization (HE) method usually results in extreme over-enhancement, which causes the unnatural look and visual artifacts in the processed image.
In this thesis, we propose a novel histogram equalization method based on the automatic histogram separation along with the piecewise transformation function. The five enhanced methods including HE, BBHE, DSIHE, RSIHE, and the proposed method are implemented by C language for comparison. We firstly analyse the qualitative and quantitative evaluation to prove our approach is efficient. Afterwards, the power consumption is estimated by using Wattch toolset. Experimental results show that the proposed Automatic Equal-Separated Histogram Equalization (AESHE) not only keeps the shape features of the original histogram but also enhances the contrast effectively even though the processing time and the power consumption have little higher than other methods.

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