An index, indicating a vector representing a spatial relationship between a block to be encoded and at least one block spatially at the periphery of the block to be encoded, is encoded in a case where an coding mode to encode the block to be encoded is a first coding mode, and an index, indicating a vector representing a spatial relationship between the block to be encoded and at least one block spatially at the periphery of the block to be encoded, and a vector correlated with a block within an image that is different from the image to be encoded, is encoded in a case where the coding mode to encode the block to be encoded is a second coding mode.

Frames from an image stream or streams are processed by independently operating digital signal processors (DSPs), with only frame checking microprocessors operating in a lockstep mode. In one example, two DSP are operating on alternate frames. Each DSP processes the frames and produces prediction values for the next frame. The lockstep microprocessors develop their own next frame prediction. The lockstep processors compare issued frames and previously developed predicted frames for consistency. If the predictions are close enough, the issued frame passes the test. The lockstep processors then compare the issued frame to the preceding two frames for a similar consistency check. If the prior frames are also close enough, the issued frame is acceptable. In another example, hardware checkers are provided to compare the present frame with a larger number of prior frames. The hardware checkers provide comparison results to the lockstep processors to compare against allowable variation limits.

Frames from an image stream or streams are processed by independently operating digital signal processors (DSPs), with only frame checking microprocessors operating in a lockstep mode. In one example, two DSP are operating on alternate frames. Each DSP processes the frames and produces prediction values for the next frame. The lockstep microprocessors develop their own next frame prediction. The lockstep processors compare issued frames and previously developed predicted frames for consistency. If the predictions are close enough, the issued frame passes the test. The lockstep processors then compare the issued frame to the preceding two frames for a similar consistency check. If the prior frames are also close enough, the issued frame is acceptable. In another example, hardware checkers are provided to compare the present frame with a larger number of prior frames. The hardware checkers provide comparison results to the lockstep processors to compare against allowable variation limits.

A video coder is configured to determine bi-directional motion vectors of a current block of the video data and determine that a condition is satisfied with respect to the current block based on each component of the bi-directional motion vectors of the current block being less than a threshold value. The video coder is further configured to, based on the condition being satisfied with respect to the current block, early terminate application of a motion vector refinement process to the bi-directional motion vectors of the current block. The video coder is further configured to determine a prediction block for the current block based on the bi-directional motion vectors of the current block and reconstruct the current block based on the prediction block for the current block.

A method of encoding a three-dimensional (3D) image including a point cloud includes grouping a plurality of points included in the point cloud into at least one segment; generating patches by projecting the points included in the segment onto a predetermined plane in a first direction or a second direction; generating two-dimensional (2D) images by packing the patches; and generating and outputting a bitstream including information about a direction in which each point is projected to generate the patches and information about the 2D images.

A load in processing of searching for a motion vector is reduced. In order to solve the problem described above, a motion vector derivation apparatus (3032, 3036 to 3038) according to one aspect of the present invention that derives a motion vector to be referred to for generating a prediction image to be used for coding or decoding of a video includes a motion vector search unit (30373) configured to search for a motion vector on a prediction unit basis through matching processing. The motion vector search unit (30373) is configured to stop search of the motion vector, depending on whether or not a conditional expression according to a pixel bit-depth is satisfied.

Methods and apparatuses of determining an alignment level between motion compensated reference patches for reducing motion vector refinement steps are provided. According to one method, obtaining, by a decoder, motion compensated interpolated samples based on sub-pixel accurate merge motion vectors from a bilinear motion compensated interpolation; computing, by the decoder, a sum of absolute differences (SAD) between two motion compensated reference patches using a subset of the motion compensated interpolated samples; determining, by the decoder, whether the SAD is less than a coding unit (CU) size-dependent threshold value; when the SAD is less than the CU size-dependent threshold value: skipping remaining decoder-side motion vector refinement (DMVR) process steps; and performing final motion compensation; and when the SAD is not less than the CU size-dependent threshold value: performing the remaining DMVR process steps; and performing the final motion compensation.

Methods and apparatuses of determining an alignment level between motion compensated reference patches for reducing motion vector refinement steps are provided. According to one method, obtaining, by a decoder, motion compensated interpolated samples based on sub-pixel accurate merge motion vectors from a bilinear motion compensated interpolation; computing, by the decoder, a sum of absolute differences (SAD) between two motion compensated reference patches using a subset of the motion compensated interpolated samples; determining, by the decoder, whether the SAD is less than a coding unit (CU) size-dependent threshold value; when the SAD is less than the CU size-dependent threshold value: skipping remaining decoder-side motion vector refinement (DMVR) process steps; and performing final motion compensation; and when the SAD is not less than the CU size-dependent threshold value: performing the remaining DMVR process steps; and performing the final motion compensation.

A video coder is configured to use bi-directional optical flow (BDOF) to determine, based on a first reference picture and a second reference picture, a prediction block for a current block of a current picture of the video data. The first reference picture is a first picture order count (POC) distance from the current picture. The second reference picture is a second POC distance from the current picture. The first POC distance must be equal to the second POC distance for BDOF to be used to determine the prediction block for the current block. The video coder codes, according to the video coding standard, the current block based on the prediction block for the current block.

Methods and apparatuses of determining an alignment level between motion compensated reference patches for reducing motion vector refinement steps are provided. According to one method, obtaining, by a decoder, motion compensated interpolated samples based on sub-pixel accurate merge motion vectors from a bilinear motion compensated interpolation; computing, by the decoder, a sum of absolute differences (SAD) between two motion compensated reference patches using a subset of the motion compensated interpolated samples; determining, by the decoder, whether the SAD is less than a coding unit (CU) size-dependent threshold value; when the SAD is less than the CU size-dependent threshold value: skipping remaining decoder-side motion vector refinement (DMVR) process steps; and performing final motion compensation; and when the SAD is not less than the CU size-dependent threshold value: performing the remaining DMVR process steps; and performing the final motion compensation.