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In this paper, we propose a new frame rate upconversion (FRUC) method for temporal video quality enhancement. The proposed algorithm generates an interpolated frame in between two given frames based on a bi-directional mesh interpolation (BMI), in order to cope with not only translation, but also with scale and rotation changes. BMI performance is highly influenced by the accuracy of the correspondences between the control points in the two frames. To achieve an accurate dense motion vector map (MVM) through bi-directional and unidirectional motion estimation, an initial MVM is formed by the transmitted motion vectors from coded bitstream with low computational complexity. Then, the interpolated frame is generated by frame-based BMI with the dense MVM. In our experiments, we found out that the proposed algorithm is about 2dB better than several conventional FRUC methods. Furthermore, block artifacts and blur artifacts are significantly diminished by the proposed algorithm. Index Terms-Frame rate up-conversion, mesh interpolation, uni-directional motion estimation, bi-directional motion estimation I. INTRODUCTIONrame rate up-conversion (FRUC) refers to the postprocessing methods whose goal is to improve video quality by increasing the frame rate. A number of FRUC algorithms have been developed [1]- [15], and they can be classified into two main categories. One category contains methods that generate interpolated frames without explicitly considering motion. These algorithms analyze mathematical relations regarding pixel intensity changes among neighboring frames. The second category includes motion-based techniques. Most of these methods generate interpolated frames with the help of block-based motion estimation and compensation [2]- [15]. These approaches are able to improve video quality with natural continuity of motion. However, the block-based translational motion model can lead to blocking artifacts.Mesh-based techniques [17], [18] are another alternative in an attempt to represent more realistic motion. Like most other interpolation methods, the mesh-based interpolation is sensitive to occlusions. In order to deal with these occlusions, the proposed method interpolates the target frame through bi-

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This paper proposes an early termination method of a block vector search for fast encoding of high efficiency video coding (HEVC) screen content coding (SCC). In the proposed algorithm, two blocks indicated by two block vector predictors (BVPs) were first employed as an intra block copy (IBC) search. If the sum of absolute difference (SAD) value of the block is less than a threshold defined empirically, an IBC BV search is terminated early. The initial threshold for early termination is derived by statistical analysis and it can be modified adaptively based on a quantization parameter (QP). The proposed algorithm is evaluated on SCM-2.0 under all intra (AI) coding configurations. Experimental results show that the proposed algorithm reduces IBC BV search time by 29.23% on average while the average BD-rate loss is 0.41% under the HEVC SCC common test conditions (CTC).