Fast intra prediction decision algorithm for the QTBT structure

Abstract

The Joint Exploration Team JVET, created in October 2015, between ITU-T and ISO, is currently preparing the next video coding standard called Versatile Video Coding (VVC). This proposition, which is expected to be finalized by the end of 2020, is designed to address high-resolution 8k video applications and emerging applications such as 360-degree omnidirectional and High Dynamic Range (HDR) videos. The new proposition comes with different improvements, especially for the intra prediction module. An increased set of angular modes IPM (Intra Prediction Modes) was proposed to model angular textures more accurately. In addition, a new partition structure called Quadtree plus Binary Tree (QTBT) replaced the quadtree structure. These enhancements aiming at increasing the coding efficiency have led to burden coding complexity particularly in terms of coding time. In this paper, a fast intra prediction mode decision algorithm was proposed for the different QTBT binary depths. Experimental results show the effectiveness of the proposed method, which allows a complexity reduction of 56.32% with a negligible loss in video quality of −0.02 dB on average and a bite rate increase between 1% and 3%.