Correa, GuilhermeAssunção, PedroAgostini, LucianoCruz, Luis A. da Silva2025-07-082025-07-082015-03Comnuicações, ESTG, IT - restricted access G. Correa, P. Assuncao, L. Agostini and L. A. da Silva Cruz, "Four-step algorithm for early termination in HEVC inter-frame prediction based on decision trees," 2014 IEEE Visual Communications and Image Processing Conference, Valletta, Malta, 2014, pp. 65-68, doi: 10.1109/VCIP.2014.7051505.978-147996139-9http://hdl.handle.net/10400.8/13571Article number - 7051505Conference name - 2014 IEEE Visual Communications and Image Processing Conference, VCIP 2014 Conference date - 7 December 2014 - 10 December 2014The flexible encoding structures of High Efficiency Video Coding (HEVC) are the main responsible for the improvements of the standard in terms of compression efficiency in comparison to its predecessors. However, the flexibility provided by these structures is accompanied by high levels of computational complexity, since more options are considered in a Rate-Distortion (R-D) optimization scheme. In this paper, we propose a four-step early-termination method, which decides whether the inter mode decision should be halted without testing all possibilities. The method employs a set of decision trees, which are trained offline once, using information from unconstrained HEVC encoding runs. The resulting trees present a mode decision accuracy ranging from 97.6% to 99.4% with a negligible computational overhead. The method is capable of achieving an average computational complexity decrease of 49% at the cost of a very small Bjontegaard Delta (BD)-rate increase (0.58%).engblock partitioningdecision treesfast mode decisionHEVCinter predictionconference paper10.1109/vcip.2014.7051505