Systems, methods, and instrumentalities are described herein for calculating local illumination compensation (LIC) parameters for bi-predicted coding unit (CU). The LIC parameters may be used to generate adjusted samples for the current CU and to address local illumination changes that may exist among temporal neighboring pictures. LIC parameters may be calculated based on bi-predicted reference template samples and template samples for a current CU. Bi-predicted reference template samples may be generated based on reference template samples neighboring temporal reference CUs. For example, the bi-predicted reference template samples may be generated based on averaging the reference template samples. The reference template samples may correspond to template samples for the current CU. A CU may be or may include a coding block and/or a sub-block that may be derived by dividing the coding block.

An image decoding method according to the present invention comprises: a step of acquiring an initial motion vector of a current block; a step of deriving a refined motion vector for each of a plurality of search points on the basis of the initial motion vector; and a step of acquiring a motion vector of the current block on the basis of the refined motion vector of any one of the plurality of search points.

A method for processing a video includes performing a determination, by a processor, that a first video block is partitioned to include a first prediction portion that is non-rectangular and non-square; adding a first motion vector (MV) prediction candidate associated with the first prediction portion to a motion candidate list associated with the first video block, wherein the first MV prediction candidate is derived from a sub-block MV prediction candidate; and performing further processing of the first video block using the motion candidate list.

A method for processing a video includes performing a determination, by a processor, that a first video block is partitioned to include a first prediction portion that is non-rectangular and non-square; adding a first motion vector (MV) prediction candidate associated with the first prediction portion to a motion candidate list associated with the first video block, wherein the first MV prediction candidate is derived from a sub-block MV prediction candidate; and performing further processing of the first video block using the motion candidate list.

A method for video encoding is provided. The method includes: partitioning a frame of video data into a plurality of blocks; obtaining a current prediction of a current block of the plurality of blocks using one or more motion vectors of the current block; obtaining one or more collocated predictions of the current block using one or more motion vectors of one or more neighbor blocks of the current block in respective one or more blending areas, where each of the one or more blending areas is at least part of the current block and adjustable based at least on the partitioning; and obtaining a combined prediction of the current block by combing the current prediction with the one or more collocated predictions.

High efficiency video coding (HEVC) enhancements are described for intra-block copying for reducing motion vector (MV) coding redundancy and enhancing in range extensions (RExt) by selecting a default block my predictor. In reducing MV data redundancy, the value of MVx and/or MVy can have a baseline at the width (W), or height (H) of the respective block, whereby fewer bits need to be encoded. One embodiment for enhancing RExt provides an improved selection of a default block vector predictor for the first CU performing intra-block copying in a CTU.

A method is performed in an encoder for encoding a video stream captured by a camera, and a computer program product and encoder implementing the method.

Techniques are described to code motion vectors using reference motion vectors to reduce the amount of bits needed. One method includes determining, for a current block of the video bitstream, a reference motion vector from a varying number of candidate reference motion vectors, wherein the reference motion vector is associated with a reference block and includes a predicted portion and a residual portion; selecting a probability context model for the current block by evaluating the residual portion of the reference motion vector with one or more thresholds; and entropy decoding, for the current block using a processor, a motion vector residual associated with the current block using the probability context model.

Techniques are described to code motion vectors using reference motion vectors to reduce the amount of bits needed. One method includes determining, for a current block of the video bitstream, a reference motion vector from a varying number of candidate reference motion vectors, wherein the reference motion vector is associated with a reference block and includes a predicted portion and a residual portion; selecting a probability context model for the current block by evaluating the residual portion of the reference motion vector with one or more thresholds; and entropy decoding, for the current block using a processor, a motion vector residual associated with the current block using the probability context model.

An example device for decoding video data includes a video decoder configured to decode one or more syntax elements at a region-tree level of a region-tree of a tree data structure for a coding tree block (CTB) of video data, the region-tree having one or more region-tree nodes including region-tree leaf and non-leaf nodes, each of the region-tree non-leaf nodes having at least four child region-tree nodes, decode one or more syntax elements at a prediction-tree level for each of the region-tree leaf nodes of one or more prediction trees of the tree data structure for the CTB, the prediction trees each having one or more prediction-tree leaf and non-leaf nodes, each of the prediction-tree non-leaf nodes having at least two child prediction-tree nodes, each of the prediction leaf nodes defining respective coding units (CUs), and decode video data for each of the CUs.