隨著3C產品與科技日益提升，高解析度的顯示器、平板電腦及智慧型手機已是目前消費性電子的主流產品。為了在高解析度設備上清晰的顯示較低階晰度的影像，發展有效的影像放大技術是一個相當重要的研究議題。植基於改良式韋納濾波器，本篇論文提出了一個有效的影像內插方法來提升放大影像的品質。首先我們在韋納濾波器中加入了距離及紋理一致性的概念，提升最小平方法的預測精確度，並利用疊代計算方式。本篇論文也提出了兩種預測模式以適應不同的紋理，此外，實驗中我們發現，傳統的雙立方內插法對於單純的水平及垂直紋理的放大可得到較佳的品質。為了融合兩種預測模式及雙立方內插法的優點，我們提出一個有效的評估函數來決定最佳的混合權重，以建構出高品質的高解析度影像。實驗結果顯示，與三種知名的內插方法(NEDI、SAI、RSAI)相較之下，我們所提出的方法除了達到較高的PSNR及SSIM值之外，在視覺效果上也有顯著的提升。

With the rapid development of consumer electronics and multimedia technology, high-resolution display, tablet PC and smart phone are becoming the current main-stream consumer electronic products.In order to show the image of low resolution on a high-resolution device clearly, developing an effective image zoom technique is an important research issue.Based on the improved Wiener filter, this thesis presents an effective image interpolation technique to enhance the quality of the enlarged image.In the proposed image interpolation technique, we first incorporate the con-text-consistency with the conventional Wiener filter and then conduct it by an iterative process so as to improve the accuracy of the least square method. In addition, this thesis also presents two prediction modes which are applicable to different textures, respectively.In the experiments, for the image with simple horizontal and vertical textures, we find that the traditional bicubic interpolation technique can deliver better enlarged quality. In order to fuse the advantages of both the two proposed prediction modes and the bicubic interpolation, we develop an effective evaluation function to determine the best fusion weights; after that, quality-superior high-resolution images can be constructed by the proposed image zoom technique. Experimental results show that the proposed image zoom technique does deliver better enlarged quality in terms of PSNR, SSIM, and visual effect when compared with the three well-known interpolation techniques, NEDI, SAI, and RSAI.

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