• 沒有找到結果。

本篇論文提供一套產生鉛筆素描草圖的自動化流程,讓使用者無須介入而自動由 影像產生出近似手繪的草圖。然而,目前筆觸是完全由直線所構成,且長度是以圖像 的長寬為基礎,對於畫面複雜的圖來說,許多小細節會顯得十分雜亂;而對於顏色對 比過大的圖,畫面色階的分層會過於零碎,使的斜筆筆觸顯得十分不自然;Sobel 由 於 kernel 過小,有許多點的向量計算不出來,如何設計一個更大的且精準的 kernel 也可以是個議題;而筆跡與力道這方面的因素在本論文比較少著墨,這是未來可以加 以改進探討的地方。

在效能方面,ETF 及 FDoG 隨著 kernel 大小的與迭代的增加,運算時間會大幅增 加,而 FDoG 在的邊緣偵測上,需要計算許多高斯濾波,需要相對較長的時間。Kang[30]

等人在 ETF 提出以兩個 1D kernel 取代 2D kernel 來降低時間而達到近似的效果,

並也說到 FDoG 的實作上,以先計算出整個梯度強度圖來降低時間複雜度。而在本論 文中的筆觸生成方法,在實作上可以在輪廓擷取時就將三種長度筆觸同時處理;在 斜線筆觸方面,兩邊方向的也可以同時處理,以降低向量走訪次數,增加效能。

本論文從人工手繪的角度切入,彷彿就像一個畫家正著手對某張影像繪製素描,

也因此讓影像更能從擬真進入到非擬真,結果也顯示在素描草圖的模擬是很成功的。

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在文檔中 鉛筆素描草圖筆觸之模擬 (頁 50-54)

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