隨著高解析度影像的需求增加與數位電視廣播系統 (DTV broadcast system)漸漸地普及，人們對於數位影像品質的要求，愈來愈來高。在數位影像的應用上，通常存在的問題就是因影像放大後所產生影像鋸齒狀與模糊狀的現象，而所造成的結果會降低影像的解析度及觀看品質。本研究的主要目的是為了解決這些問題，並且能夠保留影像邊緣的清晰度及加快放大時的運算速度。主要的方法是先透過簡單的邊緣偵測方式，找出影像邊緣。在邊緣及非邊緣的影像像素部分，分別使用不同的內插演算法，來強化影像邊緣的效果。最後，再透過邊緣平滑化修補的方法，來解決影像放大後，影像邊緣的鋸齒狀現象。經由實驗的結果可以顯示出，使用邊緣偵測的內插方式，再加上邊緣平滑化修補鋸齒邊的方法，可以提高放大後的影像品質。

As high-resolution images are demanding and digital TV is popular, people ask higher image quality than before. In digital image applications, two of the most important problems are jag and blurring effects after image magnification. The effect reduces image quality. This research mainly focuses on solving these problems by reserving clarity of image edge and accelerating the computation speed during the image zooming. The image edge is found using a simple edge detection algorithm and then a pixel is interpolated by different image zooming algorithms for an edge and non-edge. Finally, the jag effect, which is resulted from the image zooming, is modified. Simulations prove that better image quality is obtained by using the interpolation with edge detection and the edge smoothing.

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