近年來發展出越來越多支援高解析度的多媒體產品，為了能夠有效壓縮伴隨高解析度視訊檔案而來的龐大資料量，HEVC使用許多技術來進行編碼得以降低位元率。回顧先前的研究，利用雙向絕對誤差(Sum of Absolute Bi-Prediction Difference/SABPD)和模板匹配(Template Matching /TM)之解碼端輔助演算法應用於擴充型合併模式與畫面間模式決策，利用已編碼完成之資訊進行預測，在解碼端搜尋相同預測畫面，以減少需要傳送之標頭檔碼字，來節省位元率，但編碼時間也因為計算複雜度的提升有所增加。為了能夠降低畫面間預測的計算複雜度，本論文利用零區塊演算法來提早終止編碼單元的分塊，以及利用加權RDO(Rate-distortion optimization)閥值、CBF、運動向量差在預測單元合併模式和2Nx2N模式的提早終止，來節省編碼計算的時間。在最後將其結合，由實驗結果得知，與解碼端輔助HEVC相比BDBR僅上升0.894%，但編碼時間減少了55.85%之多；與HEVC標準模式相比BDBR可以下降-2.355%，編碼時間減少了48.58%之多。;In recent years, a lot of high resolution multimedia devices have been developed. In order to compress the significant data effectively, HEVC utilize multiple techniques to decrease bitrate efficiently. Review the previous research, using Sum of Absolute Bi-Prediction Differences(SABPD) and Template Matching(TM) algorithm in extended merge mode decision and inter mode decision, the Decoding-assisted HEVC utilize encoded information to predict. Decoder can predict with same information, so we can reduce transmitting header information to decrease bitrate. However, the coding time might be longer due to the increase of computational complexity. In this thesis, in order to reduce computational complexity, we proposed the Zero-block algorithm is utilized to early terminate the segmentation of Coding Unit(CU), and on the other hand, weighted RDO threshold, Coded Block Flag(CBF) and motion vector difference are utilized to early terminate the prediction mode decision in merge mode and Inter2Nx2N mode. Finally, we combine these two algorithm. According to experiment results, our proposed algorithm achieves that encoding time was reduced by 55.85% and BDBR only increased by 0.894%. Compare with HEVC, we can not only reduced encoding time by 48.58% but also decreased BDBR by 2.355%.
