過去針對彩色濾波器陣列的視訊壓縮方法可區分為兩類：結構轉換式與去馬賽克式。前者雖然能夠提供較佳的壓縮品質，但卻只適用於特定樣式的彩色濾波陣列視訊；後者雖然可以適用於任意樣式的彩色濾波陣列視訊，但其壓縮品質則受到彩度抽樣而有所侷限。

在本篇論文中，我們提出兩個可適用於任意樣式之彩色濾波陣列視訊的高品質壓縮方法，其中一者是改良了前人於H.264/AVC上所提出之去馬賽克式的彩色濾波陣列視訊壓縮方法；另一者則是於高效能視訊編碼(High Efficiency Video Coding, HEVC)上提出一套嶄新的彩色濾波陣列視訊壓縮方法。在我們所提出的第一個方法中，針對Yang等人所提出之任意樣式彩色濾波陣列視訊壓縮方法，在彩度抽樣後產生之色彩值偏移問題，透過修改對馬賽克視訊品質也有影響的亮度資訊，來取代前人完全保留原始亮度資訊的作法，使得色彩值偏移的問題能被有效地解決；而在所提出的第二個彩色濾波陣列的視訊壓縮方法中，我們則直接對彩色濾波陣列視訊進行壓縮，由於不需經過彩度抽樣和結構轉換，因此可得到較佳的壓縮品質且適用於任意樣式之彩色濾波陣列視訊。當給定視訊之彩色濾波陣列樣式資訊後，針對當前待壓縮之區塊，我們提出的第二個方法將會對幅內預測所使用到的鄰近參考像素，先施以通用型的去馬賽克演算法，接著再利用去馬賽克後的全彩之參考像素對當前區塊作幅內預測，其中在預測區塊內之任一像素值時，則是採用相同色彩的參考像素進行預測。

實驗結果顯示我們所提出的兩個彩色濾波器陣列視訊壓縮方法共包含以下優勢：
1.適用於任意樣式之彩色濾波器陣列視訊
2.壓縮品質不受彩度抽樣的影響
3.與Yang等人在H.264/AVC所提出的通用型視訊壓縮方法相比，具有較好的壓縮品質與較高的壓縮率。

Recently, compressing red-green-blue (RGB) color-filter-array(CFA) videos has been studied extensively, in which the structure conversion based and the demosaicking based compression schemes are mainstream. The former can deliver higher compression quality but has difficulties in converting irregular RGB-CFA structures, while the latter is applicable to arbitrary RGB-CFA videos but suffers from the RGB color deviation problem due to the chroma subsampling.

In this thesis, we present two novel RGB-CFA video compression schemes, where one is an improved demosaicking based compression scheme in H.264/AVC and the other is a novel CFA video compression scheme in high efficiency video coding (HEVC). First, to solve the RGB color deviation problem which occurs in the existing demosaicking based compression schemes in H.264/AVC, we propose a color deviation-free universal subsampling strategy for compressing arbitrary RGB-CFA videos in H.264/AVC.
Under the framework of Yang et al.'s universal chroma subsampling strategy, we replace retaining the original Y luma component with adopting a optimal modification for the Y luma component such that the RGB color deviation problem can be resolved. Next, to develop a CFA video compression scheme which is applicable in HEVC and avoid the problems of the existing structure conversion based and demosaicking based CFA video compression schemes in H.264/AVC, we propose a high quality universal intra coding scheme for compressing arbitrary RGB-CFA videos based on HEVC. The proposed scheme first demosaicks the neighboring reference pixels and then predicts, according to the CFA structure, the color value of the target pixel using the color values of the identical components in the reference pixels. The proposed scheme avoids the difficulty in converting irregular CFA structure and the quality degradation caused by chroma subsampling. Experimental results demonstrate that the proposed RGB-CFA video compression schemes achieve better quality of the reconstructed RGB-CFA videos under the same bitrate, when compared with the existing ones.

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