最近基於深度學習的方法已經在圖像修復領域非常進步。然而，目前存在的方法時常在修補完圖片之後，遮罩區域的邊界仍然是模糊的，甚至容易生成扭曲的結構。這主要是因為過去方法使用卷積神經網路從遮罩周圍的空間複製信息修補的無效導致，對於較具語義的圖片（人臉）無法利用周圍已知訊息的修補方法
來達成。因此，圖像中的輪廓線索是相當重要的，我們可以透過此訊息更明確的知道物體之間的界線。在這篇論文中，我們提出兩階段的圖像修補架構，分別為邊緣修補網路與多尺度的圖像修補網路。邊緣修補網路主要生成缺失區域的邊緣輪廓，我們利用鉸鏈損失進行訓練以確定生成結果的真偽，同時使修補完成的邊緣更加逼真。此外，圖像修補網絡從低維度到高維度漸進的生成圖像，利用上一階段修補完成的邊緣作為條件放入多尺度圖像修補網絡一起訓練，使得缺失部分的邊界更合理，同時增加網路中的感受野。實驗結果表明在不同遮罩大小情況下，我們的方法可以生成比現有技術方法更好的結果。

Recent deep learning­based approaches have shown significant improvements in image completion. However, the existing methods often create distorted structures or blurry textures inconsistent with surrounding areas. This is mainly due to the ineffectiveness of convolutional neural networks in copying information from distant spatial locations. Therefore, the contour cues in the image are quite important, and we can more definitely confirm the boundary between objects by this information. In this thesis, we propose a two­-stage architecture for image completion, which is the edge completion network and the coarse­to­fine image completion network. Edge completion network generates edges in missing regions, we use hinge loss for training to determine whether the input is real or fake, it also makes the completed edges more realistic. Then, image completion net­work generates an image from low dimension to high dimension, the completed edges are as a condition fed into both coarse network and refine network that makes the boundary of the missing parts more reasonable, meanwhile increase larger receptive field. Experi­ment results show that our method can generate better quality images than the state-­of-­art approaches in both quantitatively and qualitatively.

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