在影像處理當中，清楚呈現邊緣與增強邊緣，同時也去除不必要的雜訊是最基本的工作。當我們使用數位相機截取影像時，很常見的是彩色影像當中摻雜了各式各樣的雜訊，因此，雜訊濾波器在此是相當必要的。而雜訊濾除的最大問題是會降低影像的銳利度，換句話說，光學鏡頭瑕疵對於影像的影響就有如低通濾波器一般，它會導致影像的模糊情形，習慣上，這樣的情形會應用邊緣增強演算法來改進影像的銳利度，但做邊緣增強的影像處理也常常會同時將雜訊的訊號也同時增強。在本論文中，我們提出一個整合型的流程架構來改善影像的品質。其中結合了在適合的影像空間下所做的彩色邊緣偵測、同時使用到相似度濾波器與距離濾波器的雙邊濾波器與邊緣增強演算法， 從實驗結果可看出這個影像處理流程可以達到濾除雜訊的同時也保留並增強邊緣的效果。

Removing noise while preserving and enhancing edges is one of the most fundamental operations of image/video processing. When taking pictures with digital cameras, it is frequently found that the color images are corrupted by miscellaneous noise and, hence, noise filtering is necessary. The difficulty is that usually the filtering will reduce the sharpness of the image. On the other hand, optical lens imperfections are usually equivalent to spatial low pass filters and tend to result in blurred images. It is customary to apply edge enhancement algorithm on the image in order to improve the sharpness, but this process usually increase the noise level as a by-product. In this paper, we present a new integrated approach to address these issues. The proposed approach combines color edge detection, bilateral and trilateral noise filter using range filter and domain filter, and edge enhancement based on suitable color spaces. The experimental results show that the proposed approach can effectively reduce the noise while preserving and enhancing edges.

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