作為H.264/AVC後代標準，高效率視訊編碼 (High Efficiency Video Coding，簡稱HEVC) 在相同的感知影像品質下實現了約50%的bit rate降低。以畫面內預測為例，不同於H.264/AVC中使用9種內預測模式來完成，HEVC利用多達35種內預測模式來提升影像壓縮率，同時引入了四元樹結構 (Quad-tree structure) 編碼單元 ( Coding unit，簡稱CU) 的大小可以從最大64×64 至最小8×8。因此，與其先前的畫面內預測編碼 (Intra frame coding) 相比，編碼複雜度增加了好幾倍。
本論文提出了快速模式決策方法基於區塊紋理偵測、修正最可能模式 (Most probable mode)、和使用SATD分類，以降低HEVC畫面內預測編碼的編碼複雜度，同時保持率失真 (Rate-distortion，簡稱RD) 性能。實驗結果表明，在All-Intra配置下和與HEVC參考軟件HM 16.7對比，所提出的快速模式決策方法平均可節省約44%的計算複雜度，只有1.04%的Bjøntegaard delta bit rate (BDBR) 損耗。

As a successor to H.264/AVC, High Efficiency Video Coding standard known as HEVC achieves about 50% bit-rate reduction under the same perceptual video quality compared to its predecessor. To make the coding efficiency higher, HEVC introduced new coding feature, which is adding intra prediction modes up to 35 prediction modes instead of 9 prediction modes in H.264/AVC and introduced a quad-tree structured coding unit from the largest CU 64 × 64 to the smallest CU 8 × 8. However, the encoding complexity increases several times compared to its predecessor intra coding.
In this dissertation, fast intra mode decision based on block texture detection, modified most probable mode and SATD classification are proposed to reduce the encoding complexity of HEVC intra coding while maintaining the rate-distortion (RD) performance. Experimental results show that the proposed fast intra coding method could save about 44% of computational complexity on average with a 1.02% Bjøntegaard delta bitrates (BDBR) increases for the HEVC reference software HM 16.7 under all-intra configuration.

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