Intra Template Matching Prediction with Fusion Techniques

Intra template matching prediction (Intra TMP) is a promising intra prediction tool which generates the prediction block by copying from a reconstructed block of the current frame. The position of the reconstructed block is derived by template matching at both encoder and decoder. Intra TMP has been adopted in enhanced compression model (ECM) for both screen content and natural content due to its outstanding trade-off between coding efficiency and complexity. This paper describes an advanced intra TMP algorithm with fusion techniques to further improve the coding efficiency. The proposed intra TMP fusion scheme includes the following aspects: 1) extended template matching search range, 2) improved search procedure with multiple candidates, 3) adaptive fusion method with template updating, and 4) support fractional-pel precision in intra TMP. Experimental results show that the proposed intra TMP fusion scheme provides 0.76% average luma Bjøntegaard delta rate (BD-rate) reduction with negligible runtime increase over ECM-8.0 in all-intra configuration.