臺灣博碩士論文加值系統

現在的安全監控系統大多以網路攝影機為視訊來源，並以H.264做為視訊的壓縮標準。H.264擁有優越的壓縮率與高畫面品質，但這也使得它的計算量非常龐大，如果想要同時解碼多個串流，普通的電腦難以達成。本論文提出一個在頻率域底下利用影像DC值來達成降解析的方法，藉此減少計算量來加快解碼速度。由於我們取得資料是做完熵解碼之後的冗餘值(residual)，因此想要得到真實值(real value)就必須先還原預測值(predictor)。通常H.264都是在像素域還原預測值，我們利用離散餘弦轉換將像素域改在頻率域還原，一般降解析方法是在像素域使用雙線性內插，但因我們使用頻率域擷取DC值，所以擷取時也順便做降解析。實驗結果驗證所提方法的正確性與有效。

More and more IP camera are used by surveillance system, and H.264 as the video compression standard. H.264 has excellent compression ratio and high image quality, but it also makes it very large amount of computation. If you want to decode multiple streams simultaneously that is difficult to reach the common computer. This paper proposes a method to use DC image to reach downsize, thereby reducing the amount of computation to accelerate decoding speed. Since we get residual data after entropy decoding, therefore you want to get the real value must first restore the predicted value. H.264 is usually predictive value reduction in pixel domain, we use the discrete cosine transform to change pixel domain to frequency domain. Generally bilinear interpolation is used to downsize method in pixel domain, but we capture DC value in frequency domain that will downsize.

目錄
第一章 前言 1
1.1研究背景與動機 1
1.2相關文獻探討 2
1.3論文架構 3
第二章 H.264編解碼器介紹 5
2.1 H.264壓縮標準簡介 5
2.2 畫面預測 5
2.2.1 畫面內預測 5
2.2.2 畫面間預測 7
第三章 論文方法 11
3.1論文所提方法 12
3.2畫面內預測 12
3.2.1垂直預測 13
3.2.2水平預測 16
3.2.3 DC預測 19
3.3畫面間預測 20
3.3.1 取得MV值 20
3.3.2 動態補償 20
第四章 實驗結果 23
4.1實驗環境 23
4.2實驗結果 23
第五章 結論與未來研究方向 27
5.1結論 27
5.2未來研究方向 27
參考文獻 28

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