Enhanced Intra Prediction Modes Signalling In Hevc

The High Efficiency Video Coding (HEVC) standard defines 35 Intra Prediction Modes (IPM) to provide an efficient compression of intra coded blocks. To signal these IPMs to the decoder a list of 3 Most Probable Modes (MPM) is created based on the IPMs of the neighbour Intra coded blocks. These MPMs will be transmitted in the bitstream with a reduced number of bits. However, the signalling scheme used in HEVC is not optimal and can be further improved. In this paper a method is proposed to enhance the Intra mode signalling in HEVC. The IPM signalling is first modelled as a tree with forks and leaves representing tests and labels, respectively. The proposed solution introduces new decision tree process by adding new tests and new labels not considered in HEVC. This solution provides a systematic way to find the best signalling scheme for a given set of data. Experimental results show that the proposed solution enables to reduce the BD-Rate by 0.38% in all Intra coding configuration.