MPEG-2中交錯式畫面之視訊品質增益

Abstract

延續了MPEG-I 視訊標準的畫面影像(frame)的設計，在MPEG-II 視訊標準中還加入了視場影像(field)的設計。並且將畫面影像(frame)細分成非交錯式畫面影像(progressive frame)與交錯式畫面影像(interlaced frame)兩種，其中交錯式畫面影像為不同時間的視場影像所組成。此外畫面影像適用於非交錯式顯示系統中，視場影像適用於交錯式顯示系統中。但是當交錯式畫面影像在非交錯式顯示系統中顯示時有時會有影像鋸齒狀的產生。本論文針對非交錯式顯示系統中顯示交錯式畫面影像所造成的影像鋸齒狀問題提出一個新的視覺品質改善方法。 所提出的視覺改善方法結合於MPEG-2視訊解壓縮過程，並且利用解壓縮資訊中的時間與空間資訊達到具有較低的運算量與較高的改善後視覺品質。

Compared to MPEG-I video standard using frame picture as picture mode, MPEG-II video standard has adopted field picture as its alternate picture mode besides frame picture. Furthermore, progressive frame and interlaced frame are two kinds of frame pictures in MPEG-2 video standard. Interlaced frame combines with two field pictures at difference time instant. Frame picture is used in progressive monitor, and field picture is used in interlaced monitor; but sawtooth effect sometime will arise when display interlaced frame in progressive monitor. Our thesis proposes a new video enhancement method being used to reduce sawtooth effect due to displaying interlaced frame in progressive monitor. Our video enhancement method combine itself with MPEG-2 video decoding process. Also, our method utilizes temporal and spatial information of video decoding information to have lower computational complexity and higher visual quality.