Block boundary filtering for intra prediction samples

Abstract

This paper presents a new intra prediction technique for HEVC, which is next-generation video coding standard that has collaboratively been developed by ISO/MPEG and ITU-T/VCEG. On intra coding for HEVC, extension of MPEG4-AVC/H.264-like intra prediction scheme has been studied. In this conventional scheme, the prediction block is generated by simply copying adjacent reference samples, interpolating the reference samples toward prediction direction or averaging the reference samples. Thus, signal discontinuity between prediction block and adjacent reconstructed blocks could occur, which causes loss of coding efficiency of residual signal. In this paper, we propose an adaptive filtering scheme for intra prediction samples generated by either DC or directional prediction that solves the above issue. According to our evaluation, the proposed scheme achieves approximately 0.6% bitrate savings on average compared to the conventional AVC-style intra coding.