New fast search algorithm for base layer of H.264 scalable video coding extension

In this contribution, a fast search motion estimation algorithm for H.264/AVC SVC (scalable video coding) base layer with hierarchical B-frame structure for temporal decomposition is presented and compared with fast search motion estimation algorithm in JSVM software, that is the reference software for H.264/AVC SVC. The proposed technique is a block-matching based motion estimation algorithm working in two steps, called Coarse search and Fine search. The Coarse search is performed for each frame in display order, and for each 16x16 macroblock chooses the best motion vector at half pel accuracy. Fine search is performed for each frame in encoding order and finds the best prediction for each block type, reference frame and direction, choosing the best motion vector at quarter pel accuracy using R-D optimization. Both Coarse and Fine Search test 3 spatial and 3 temporal predictors, and add to the best one a set of updates.