A Fast Prediction Mode Selection Algorithm Based on Spatio-Temporal Correlation of Inter-prediction and Intra-prediction Blocks

This study present a fast mode selection algorithm for a AVS2 encoder. At present, the traversal algorithm is adopted in the selection of prediction modes of the coding block in AVS2. Firstly the inter-prediction RDcost of the current block is calculated, and then the intra-prediction RDcost is calculated, the appropriate prediction mode is selected by comparing the RDcost. This scheme performs two prediction mode algorithms when encoding a block, it can select the appropriate prediction mode accurately, but it also generates a huge amount of computation. This proposal proposes a fast prediction mode selection algorithm based on spatio-temporal correlation of inter-prediction and intra-prediction blocks. According to the correlation of number and position of inter-prediction and intra-prediction blocks of adjacent frames or the same frame in the same video, we can quickly judge the prediction mode of the uncoded block, avoid inter-prediction or intra-prediction operations, and reduce the amount of computation and coding complexity. The experimental results show that this proposal can reduce the coding time by 2% for twelve universal test sequences, the total bit rate of the video is slightly increased, and the PSNR is slightly reduced.