Saliency aware fast intra coding algorithm for HEVC

In this paper, a saliency aware fast intra coding algorithm for HEVC is proposed consists of perceptual intra coding and fast intra prediction mode decision algorithm. Firstly, based on the visual saliency detection, an adaptive CU splitting method is proposed to reduce intra encoding complexity. Furthermore, quantization parameter is adaptively adjusted at the CU level according to the relative importance of each CU and distortion is efficiently controlled. Secondly, a fast intra prediction mode decision algorithm with step halving rough mode decision method and early modes pruning algorithm is presented to selectively check the potential modes and effectively reduce the complexity of computation. Experimental results show that 45.39% encoding time can be reduced by the proposed saliency aware fast intra coding algorithm. Furthermore, our proposed algorithm can achieves 2.18% bit rate reduction on average with negligible perceptual quality loss.