H.264為了能夠達到好的壓縮效率，採用更複雜的編碼架構，使得編碼器的複雜度大幅提升，本論文主要是改善區塊決策與移動估計的部份。 在此篇論文中，我們先回顧零區塊的特性與ZBD(zero-block mode decision)演算法，得知ZBD演算法適用於高量化參數及慢速影像，但是在低量化參數及複雜移動的影像上的表現有改進的空間，故提出以決策樣本取代零區塊數目的基於零區塊決策樣本的模式決策演算法，之後再加入移動預估加速的概念。實驗結果顯示我們所提出的方法在影像品質幾乎沒有失真的情況下，能有效降低編碼端的運算複雜度，也增進了在低量化參數及複雜移動的影像上的效能。H.264/AVC is the latest video coding standard. In order to achieve the highest coding efficiency, H.264 adopts complicated coding schemes, employing motion compensation with variable blocks sizes motion estimation, multiple reference frames motion estimation, de-blocking filter and integer transform, etc. Unfortunately, these features incur a considerable increase in encoder complexity, mainly regards to mode decision and motion estimation. In this paper, we first review the characteristics of zero blocks and ZBD (zero-block mode decision) algorithm, that algorithm is applicable to high QP and slow video, but in low QP and complex moving images, the performance has room for improvement. We proposed the enhanced zero-block decision algorithm that used pattern to replace ZB quantity to decide best mode. Then we add the concept of motion search speed up in this paper to improve performance. Experimental results show that our proposed method almost no distortion in the image quality of the case, the encoder can reduce the computing complexity, but also improves the quantitative parameters in the low and complex moving image.
