本研究提出一個多運算子的影像調整機制，其中包含了圖縫裁減(Seam carving)、邊緣裁切(Cropping)、圖縫增加(Adding seam)以及正規化(Normalization)或影像直接縮放，故此機制又稱為SCAN。首先我們根據畫面內容物紀錄兩側最多能夠裁切的位置，並進行第一次邊緣裁切，移除影像兩側不重要的部分，並且使得兩邊裁切的數目相同。接著，我們考慮局部能量以及全域能量實作一個新的圖縫裁減方法以去移除影像中間較不重要的圖縫，此演算法可有效率地移除大量圖縫。當影像背景不複雜時，類似圖縫裁減方法可以被應用於圖縫增加之上，使得畫面更接近目標長寬比例。若影像尺寸仍未達目標，可進行第二次的影像邊緣裁切。最後在施予畫面直接縮放。實驗結果顯示所提出的方法之可行性與優勢。

This research presents a multi-operator retargeting mechanism termed “SCAN”, in which seam carving, cropping, adding seams and normalization (scaling) are applied on images in an automatic manner. The content-based cropping will first be used to remove insignificant portions on sides. Then a new seam carving algorithm based on both the global saliency and local saliency is proposed to rid of the pixels in the middle of the image. Efficiency is the major advantage of this seam carving algorithm. When the background is not complex, some seams may be inserted in a similar way as the proposed seam carving procedures to make the aspect ratio closer to the target one. Finally, the image is scaled or normalized directly. Experimental results will demonstrate the feasibility and advantages of the proposed method.

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