數位時間延遲整合(Digital Time Delay and Integration,DTDI)的馬賽克影片序列是經由高速線性掃描的相機所產生的，近來廣泛的使用在工業印刷檢測和高速影像擷取的應用中。為了減少這些影片序列儲存的記憶體需求，壓縮它們是必需的。在本篇論文中，我們提出一個在H.264/AVC 的編碼環境中使用有效的色彩取樣策略來壓縮DTDI 馬賽克的影片序列。基於RGB域和YUV域間的色彩空間轉換下，我們根據DTDI 馬賽克的結構，利用了位置選擇的策略來決定兩個色彩元素U 和V 的取樣。在一些常見的DTDI 馬賽克測試的影片中，實驗顯示，經由H.264/AVC 壓縮後的重建影像，我們提出的色彩取樣策略相對於傳統的色彩取樣有較優越的品質表現。

Digital time delay and integration (DTDI) mosaic video sequences captured by high speed DTDI line-scan cameras are commonly used in industrial print inspection and high speed capture applications. To reduce the memory requirement for saving these video sequences, it is necessary to compress them. In this paper, we present an efficient chroma subsampling strategy for compressing DTDI mosaic video sequences in H.264/AVC. Based on the color domain transform between the RGB domain and the YUV domain, a position selection strategy is proposed to determine the two subsampling chroma components, U and V, according to the DTDI mosaic structure. The quality of reconstructed DTDI video sequences is better than those reconstructed by conventional methods. By experimenting on some popular test DTDI mosaic video sequences, the results turned out to be superior than conventional ones that adopt H.264/AVC as compression standard.

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