圖像拼貼是一種常見的資料視覺化應用，透過調整影像大小和旋轉其角度，再對影像位置進行排列，形成一個新的影像組合，藉此讓使用者可以快速瀏覽資料集裡面的內容。多數的拼貼軟體僅提供使用者矩形、圓形等形狀較為單純的輪廓作為畫布的形狀，在視覺上較無藝術性。有的拼貼軟體雖然允許使用者以客製化的形狀當作畫布，但往往是藉由重疊圖像來達成輪廓的呈現，造成圖像內容的嚴重損失，且拼貼內部往往還是存有空隙。為了解決前述問題，本研究提出新的方法，依照輪廓的曲率和骨架等特徵分割畫布，設計出一個排版緊密的佈局，再根據圖像的前景物體和美感分數等資訊，找出最佳的配置組合，最終生成一張既能保留圖像重要內容，也能兼顧佈局美感的不規則形狀圖像拼貼。

Image collage is a common application of data visualization. By adjusting the size, rotation angle and position of images, a new image combination is formed, which allows users to quickly browse the images in the dataset. Most tools for collage generation only provides simple shapes such as rectangle and circle as the shape of canvas, which leads to the lack of visual artistry. Although some tools allow users to specify customized shape as the shape of canvas, they often form the contour by overlapping the images, causing significant information loss, and gaps may still exists between the images. In order to solve the aforementioned problems, we propose a new method which divides the canvas based on features of the contour such as curvature and skeleton, designs a compact layout, finds the optimal assignment based on foreground objects and aesthetic score of the images, and finally generates an irregular-shaped image collage that not only preserves the salient content of images, but also takes the visual aesthetics of layout into account.

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