利用可調式tile邊界來改善高效率視訊編碼之編碼效能

Abstract

Tiles是目前標準視頻編碼（JCT-VC）的聯合協作小組正在開發設計的高效率視頻編碼（HEVC）實行平行化的一個有用的工具。在設計中，tiles可以高度平行化編碼器和解碼器的程序，為HEVC給予了很多速度上的增進。然而，tiles會造成失真是一個嚴重的問題。 在本論文中，我們提出了一種方法以減少tiles引起的失真狀況，稱為可調式tile邊界。這種方法是簡單地在當前這張畫面被編碼前使用一些資訊去預測最好的tiles邊界位置。而且，我們也在此論文中計算此方法的上限。雖然目前的數據結果是有待突破的，但上限的資料表明，這種方法仍然有很好的前景。

High Efficiency Video Coding (HEVC) is the latest standard developed by Joint Collaborative Team on Video Coding (JCT-VC). HEVC includes a coding tool called tile which is a useful tool to achieve high coding parallelism in both encoder and decoder. However, tiles will cause rate-distortion loss that is a serious problem to be solved In this thesis, a method is proposed to reduce the rate-distortion loss caused by tiles, called Adaptive Tile Boundary. This method simply uses some information to predict the best tile boundary positions before encode the frame. Moreover, we also conduct experiments to know the upper bound of this method. Although the performance improvement of using proposed method is quite limited, the upper bound shows this method still has very good prospects.