圓弧形線條塗鴉藝術為線條描繪的一種，在微觀角度下，此圓弧形筆畫看似隨意、雜亂、毫無形體，卻在巨觀角度下，構成一幅令人驚豔的類灰階影像。此類細緻的繪圖技術，即使對天賦異稟的藝術家而言，繪製圓弧形線條塗鴉藝術仍是一項艱鉅且費時的工程。在本篇論文當中，提出了一套新的圓弧形線條塗鴉藝術自動合成系統，此合成問題，被模組化為一種參數化圓弧形曲線，並依循一條虛擬路徑繪製。為了重新呈現原輸入灰階圖之色調與特徵結構，本系統將自行調整虛擬路徑之密度與結構，並在合成過程中，動態控制參數化圓弧形曲線之大小、速度及傾斜方向。透過測試各式類型之影像作為輸入，本系統將合成其對應之圓弧形線條的塗鴉影像，以展示本系統之發展潛能，不拘限於某單一類型之輸入。此外，我們亦進行了定性與定量分析來評估此套系統產生之結果，根據評估報告顯示，本系統能有效率的產生與其他類似線條描繪、甚至是能與藝術家作品相比擬之結果。

Circular scribble art is a kind of line drawing where the seemingly random, noisy and shapeless circular scribbles at microscopic scale constitute astonishing grayscale images at macroscopic scale. Such a delicate skill has rendered the creation of circular scribble art a tedious and time-consuming task even for gifted artists. In this work, we present a novel method for automatic synthesis of circular scribble art. The synthesis problem is modeled as tracing along a virtual path using a parametric circular curve. To reproduce the tone and important edge structure of input grayscale images, the system adaptively adjusts the density and structure of virtual path, and dynamically controls the size, drawing speed and orientation of parametric circular curve during the synthesis. We demonstrate the potential of our system using several circular scribble images synthesized from a wide variety of grayscale images. A preliminary experimental studying is conducted to qualitatively and quantitatively evaluate our method. Results report that our method is efficient and generates convincing results comparable to artistic artworks.

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