使用平方反比定律設計視訊格式轉換器

DESIGN OF A SCAN CONVERTER USING THE INVERSE SQUARE LAW

陳昱勳(Yu-Hsun Chen)

指導教授 ： 蔡明傑

大同大學/電機資訊學院/電機工程學系所/碩士(2007年)

摘要

由於近年來液晶螢幕的尺寸的越來越大，視訊格式轉換愈趨重要，例如NTSC、HDTV。本論文主要以根據平方反比定律，用其定律應用於視訊格式轉換器，在放大後影像的邊緣清晰程度有所改善，且再加入鄰近像素的斜率分析，使得放大後影像的PSNR值高於雙立方補插0.4dB。
我們經由軟體Matlab的模擬結果顯示，本論文所提出的演算法，在PSNR值和Sharpness值上都有所提升。本論文以Altera CycloneII FPGA來完成硬體的實現，以24.5k位元組的內嵌記憶體和77M赫芝的工作頻率，邏輯閘總數為3,565。將SVGA（800×600）的視訊格式即時轉換至WXGA（1280×768）(60畫面/每秒)的全彩畫面格式，顯示在液晶面板上。

關鍵字

平方反比定律 ； 內插法 ； 即時 ； 現場可程式化邏輯閘陣列

並列摘要

Recently, the development of LCD screen sizes has grown up and the video format conversion has significantly increased its importance, like NTSC and HDTV. The main idea of this thesis is the improvement of image quality of video format conversion which based on the inverse square law interpolation algorithm, and our proposed algorithm is better for edge distinctness. When we use local gradient features, the PSNR will be 0.4 dB more than the bicubic interpolation.
We use Matlab to simulate the PSNR and the Sharpness. Our proposed algorithm is good for results of the PSNR and the Sharpness. The thesis implements hardware of Altera CycloneII FPGA. It works at 77MHz and uses embedded memory of 12Kbyte and also uses logic element of 3,565. The FPGA implementation of the proposed video scaling algorithm is from SVGA to WXGA on the TFT-LCD plane at the real time video rate of 60 frames/second.

並列關鍵字

Inverse square law ； Interpolation ； Real-time ； FPGA

參考文獻

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