Fast Mode Decision Algorithm for H.264/AVC Based on All-Zero Blocks Predetermination

The newly proposed video coding standard H.264/AVC by JVT can achieve much higher efficiency than previous standards. Unfortunately this comes at a cost in greatly increased complexity at the encoder mainly due to motion estimation (ME) and inter /intra prediction block mode decision. In this paper, we propose a fast mode decision algorithm for H.264/AVC based on all-zero blocks predetermination. According to the characteristics of H.264/AVC integral DCT transform and quantization, we present the adaptive detection thresholds and early termination conditions for the inter/intra prediction mode. Then these thresholds are further applied to the fast mode decision algorithm from various encoding modes, which reduce the search complexity of mode decision. The experimental results show that, compared with other mode decision algorithms, our algorithm achieves approximately 21%-41% computational saving without video-quality degradation and bit-rate increase.