使用導數的實時影像放大法

A Real-Time Image Enlargement Algorithm Using Derivatives

許甯鈞(Ning-jun Syu)

指導教授 ： 鄭嘉慶

大同大學/電機資訊學院/通訊工程研究所/碩士(2010年)

摘要

影像放大技術的目標是要將低解析度的圖像轉換成高解析度的圖像。傳統的影像插值法在保持圖像的區域幾何結構存在著侷限性；非線性插值法通常可以得到較好的效果但因具有較大的複雜度而不利於即時系統的實現。本計劃提出一個適應性的影像放大法，藉著分析目標像素的區域導數，先將像素分成四類具有不同邊界特性的類別，接著根據各像素類別設計適切的插值法。實驗顯示我們的插值法不論是在客觀的PSNR或主觀的視覺評量上，都優於傳統的插值法甚多。此外，由於運算複雜度低故亦適合即時化硬體系統的實現。

關鍵字

邊緣模型 ； 多項式內插法 ； PSNR

並列摘要

Image enlargement techniques aim to convert low-resolution images into high-resolution ones. Conventional linear interpolation methods usually have difficulty in preserving local geometric structures. Nonlinear interpolation methods could well exploit the local data properties and thus obtain better results. However, their computational complexities are much higher than those of the linear methods. In this work, we classify an image point into four classes of texture constitutions by analyzing the local properties of its derivatives. We then adaptively choose appropriate interpolation scheme according to the constitution of a pixel. Experimental results demonstrate that the proposed method produces higher visual quality than conventional methods. Furthermore, it is suitable for hardware implementation due to its low complexity.

並列關鍵字

Edge detect ； polynomial interpolation ； PSNR

參考文獻

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