Simplified Level Decision in Ratedistortion Optimized Quanitzation Ratedistortion optimized quantization (RDOQ) provides a considerable compression improvement in High efficiency video coding (HEVC) but with high computational complexity. This paper addresses a simplified RDOQ scheme for HEVC encoder by developing a level estimation (LE) bypass scheme based on the coefficient group location and transform coefficient value. Early termination of last nonzero coefficient search is also investigated to further save the number of ratedistortion cost calculation. Its experimental result shows that our proposed simplified level decision scheme can save the total quantization time by 5.11% and 4.08% with BDBR loss of just 0.02% and 0.01%, respectively under all intra and random access coding configurations.

A fast inter mode decision algorithm in H.264AVC for IPTV broadcasting services The new video coding standard H.264AVC employs the ratedistortion optimization (RDO) method for choosing the best coding mode. However, since it increases the encoder complexity tremendously, it is not suitable for realtime applications, such as IPTV broadcasting services. Therefore we need a fast mode decision algorithm to reduce its encoding time. In this paper, we propose a fast mode decision algorithm considering quantization parameter (QP) because we have noticed that the frequency of best modes depends on QP. In order to consider these characteristics, we use the coded block pattern (CBP) that has 0 value when all quantized discrete cosine transform (DCT) coefficients are zero. We also use both the early SKIP mode and early 16x16 mode decisions. Experimental results show that the proposed algorithm reduces the encoding time by 74.6% for the baseline profile and 72.8% for the main profile, compared to the H.264AVC reference software.