一種加強影像邊緣銳化的影像放大方法

A new edge enhancing method for image enlargement

林俊男(Jun-Nan Lin)

指導教授 ： 林啟芳

元智大學/資訊學院/資訊工程學系/碩士(2002年)

摘要

在數位影像放大技術中，普遍存在的問題就是影像放大後，常使得影像中物體的邊緣有鋸齒狀與模糊狀的現象產生，特別是在較高倍率的放大效果。要使放大後的影像，仍保有一定的品質，必須解決前述兩個問題。本論文的主要的目的就是要在放大影像時，仍保持影像的清晰度與對比度，並且加快放大過程的運算速度。因此在本篇論文中，將提出新的作法，首先先偵測出影像邊緣，再利用不同型態的邊緣特性來做影像放大的資訊。本論文的放大方法用來解決上述因放大時所產生的鋸齒狀與模糊狀的問題。

關鍵字

影像邊緣放大 ； 影像邊緣偵測 ； 影像放大

並列摘要

This paper presents an effective method for enhancing image resolutions. In general, there are two problems existed in the results of applying the traditional techniques of the image resize and the enhancing, i.e., the jagged edges and the blurring problem. To solve the problems, a novel method is proposed in this study to improve the quality of the enlarged images. The edges of the enlarged image are first detected, using the Sobel and the Laplacian operators. They are enhanced by different types of operators designed in the paper. The experimental results, including the subjective and the objective measurements, will show the superiority of the proposed method.

並列關鍵字

Edge Enhancement ； Edge Detection ； Image Magnification

參考文獻

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