Fast lossless compression of whole slide pathology images using HEVC intra-prediction

The lossless compression of Whole Slide pathology Images (WSIs) using HEVC is investigated in this paper. Recently proposed intra-prediction algorithms based on differential pulse-code modulation (DPCM) and edge prediction provide significant bitrate improvements for a wide range of natural and screen content sequences, including WSIs. However, coding times remain relatively high due to the high number (35) of modes to be tested. In this paper, FastIn-tra, a novel method that requires testing only four modes is proposed. Among these four modes, FastIntra introduces a novel median edge predictor designed to accurately predict edges in different directionalities. Performance evaluations on various WSIs show average compression time reductions of 23.5% with important lossless coding improvements as compared to current block-wise intra-prediction and DPCM-based methods.