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.

Fast Intra size decision and mode decision algorithm for HEVC intra coding The latest High Efficiency Video Coding (HEVC) standard could achieve much higher coding efficiency than the current mainstream video coding standards (H.264AVC). Compared with H.264AVC, H.265 saves 50% cost than H.264AVC at the same quality. But compression ratio gets improved with at least 24 times increase in computational complexity. HEVC provides a quadtree based coding unit (CU) block partitioning structure. The predication mode of CU has been extended from 8 to 35. To alleviate the encoder computational complexity, we proposed an algorithm based on complexity of CU and cart decision tree to determine whether the current CU should be divided into quadtree. In the mode decision process, we reduce the number of candidate modes involved in the rough mode decision(RMD) and the rate distortion optimization (RDO) process. The experiment results demonstrate that the proposed algorithm could significantly reduce compression time with little loss.