像素畫是一種特殊的數位繪圖表現形式，如今也自成一種藝術的表現風格。傳統上像素畫是以編輯每一像素的方式創作，這樣的過程需要耗費大量時間和心力。我們專注在其中顏色的部分，結合藝術家在創作時的思維模式，提出一套方法，先將顏色分類為幾種基本顏色再從每一種基本顏色中得到色階，最後將過於相近的顏色融合以減少顏色的數量。使得我們能用較少的顏色、在縮小的圖片，仍然較佳的表現出大尺寸解析度的原始圖片中的色彩變化，較不會有因用較少顏色數而使圖片被破壞的感受。我們也提供一套工具能讓使用者，透過簡單的調整就能快速地得到這些結果，或是以得到的結果或色彩作為基礎，再進行像素畫的創作。

Pixel art is a special form of digital art. And it have become a unique style of digital art works. Traditionally it means these art works have to be edited pixel-by-pixel which takes a lot of time and effort. We focus on the color selection phase of creating pixel art. We inspired by the work flow of artistes. Presenting a method first select few base colors then generate a ramp from each base color, finally using merge of colors to reduce the number of colors we used. Thus, our result images with a lesser number of colors and downscaled size we still can preserve the relative color differences of the origin image and not getting so much feeling that image quality being compromised. Also we provide a user-friendly tool. So users can easily get the result they want to either use the result image directly or use the result color palette to create the pixel art work in other ways they want.

摘要 III
Abstract IV
1. 介紹(Introduction) 6
2. 相關研究(Related Work) 11
3. 方法(Method) 13
3.1 決定基本顏色 (Base Color Determination) 14
3.2 產生色階(Ramp Generation) 17
3.3 融合顏色 (Merge Colors) 21
[13]4. 結果(Results) 22
5. 品質衡量(Quality Assessment) 24
5.1 量化分析(Quantitative Assessment) 24
5.2 使用者調查(User Study) 29
6. 結論(Conclusion) 31
7. 限制 (Limitations) 32
8. 未來工作(Future Work) 33
參考文獻(References) 34