基於灰階分析於區域二維雙線性內插法實現視訊格式轉換器

IMPLEMENTATION OF THE VIDEO CONVERTER USING THE LOCALLY 2-D BILINEAR INTERPOLATION BASED ON GRADIENT ANALYSIS

宋文才(Wen-Tsai Sung)

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

隨著人們對於影像品質要求的提昇，在數位影像縮放處理中，傳統的內插法並不能達成很好的效果，普遍存在的問題就是影像處理後所引起的失真的問題。
本論文主要為研究及設計以雙線性內插法為骨幹的視訊格式轉換器，加上相鄰四點奇異點的判斷及二維信號向量的判斷使得轉換後的影像結果有較高的PSNR指數，特別是在雜訊的處理及影像邊緣的區域，透過我們所提出的演算法更有明顯的改善，所以本文所提的演算法考慮即時及高效率，而且本演算法更容易使用FPGA實現硬體。
根據我們經過個人電腦軟體模擬的結果顯示，使用我們所提的演算法比較其他的演算法PSNR可提高約1.0 dB ，不必使用任何外部記憶器便可即時轉換至1280*768 (60畫面/每秒)畫面格式。

關鍵字

二維雙線性 ； FPGA ； 內插法 ； PSNR ； 即時

並列摘要

With the demand of image quality require by people in digital image processing. The general existing the distortion after image scaling. But traditional interpolation methods do not achieve a good effect.
In this thesis, we proposed to use an implementation of a scan conversion. The basis of Bi-linear interpolation use triangular judgment and 2-D vector decision base on gradient analysis can promote higher PSNR (Peak Signal Noise Ratio) of the output image quality. In addition, the proposed method can be easily implemented due to their simple structure.
Personal computer simulations (MATLAB) using read images were performed to evaluate the performance of the proposed algorithm. The performance is evaluated in respect of PSNR between the original and reconstructed image, and the results are about 1 dB better then the traditional algorithms. The proposed FPGA implementation is capable of processing high-resolution, color picture of size to 1280*768 pixels at real-time video of 60 frames/sec.

並列關鍵字

2-D Bi-linear ； FPGA ； Interpolation ； PSNR ； Real-time

參考文獻

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