Region-based Template Matching for Decoder-Side Motion Vector Derivation

In this paper, a region-based template matching method is proposed for decoder-side motion vector derivation. The proposed method is based on a template matching search algorithm, where the search window is partitioned into five regions and the index of the region to be searched is transmitted to the decoder. The final prediction signal is a linear combination of the blocks found through template matching from the given region. For a specific set of region sizes, the proposed inter method achieves an average Bjontegaard Delta bit rate gain of -3.15% for a random access configuration with 132% decoder and 201% encoder run-time respectively. The region sizes can be varied such that different trade-offs between coding gain and complexity can be obtained.