An image decoding method performed by a decoding apparatus according to the present disclosure comprises the steps of: decoding, on the basis of a bitstream, an affine flag that indicates whether affine prediction is applicable to a current block and a sub-block TMVP flag that indicates whether a temporal motion vector predictor based on a sub-block of the current block is usable; determining whether to decode a predetermined merge mode flag that indicates whether to apply a predetermined merge mode to the current block, on the basis of the decoded affine flag and the decoded sub-block TMVP flag; deriving prediction samples of the current block on the basis of the determining of whether to decode the predetermined merge mode flag; and generating reconstructed samples of the current block based on the prediction samples of the current block.

An encoder includes memory and circuitry. The circuitry: derives a first motion vector in a unit of a prediction block using a first inter frame prediction mode that uses a degree of matching between two reconstructed images of two regions in two difference pictures, the prediction block being obtained by splitting an image included in a video; and performs, in the unit of the prediction block, a first motion compensation process that generates a prediction image by referring to a spatial gradient of luminance in an image generated by performing motion compensation using the first motion vector derived.

An encoder includes memory and circuitry. The circuitry: derives a first motion vector in a unit of a prediction block using a first inter frame prediction mode that uses a degree of matching between two reconstructed images of two regions in two difference pictures, the prediction block being obtained by splitting an image included in a video; and performs, in the unit of the prediction block, a first motion compensation process that generates a prediction image by referring to a spatial gradient of luminance in an image generated by performing motion compensation using the first motion vector derived.

Methods, systems and device for hash-based motion estimation in video coding are described. An exemplary method of video processing includes determining, for a conversion between a current block of a video and a bitstream representation of the video, motion information associated with the current block using a hash-based motion search, a size of the current block being M×N, M and N being positive integers and M being not equal to N, applying, based on the motion information and a video picture comprising the current block, a prediction for the current block, and performing, based on the prediction, the conversion.

Methods, systems and device for hash-based motion estimation in video coding are described. An exemplary method of video processing includes determining, for a conversion between a current block of a video and a bitstream representation of the video, motion information associated with the current block using a hash-based motion search, a size of the current block being M×N, M and N being positive integers and M being not equal to N, applying, based on the motion information and a video picture comprising the current block, a prediction for the current block, and performing, based on the prediction, the conversion.

Systems and methods for integrated graphics rendering are disclosed. In certain embodiments, the systems and methods utilize a graphics engine, a video encoding engine, and remote client coding engine to render graphics over a network. The systems and methods involve the generation of per-pixel motion vectors, which are converted to per-block motion vectors at the graphics engine. The graphics engine injects these per-block motion vectors into a video encoding engine, such that the video encoding engine may convert those vectors into encoded video data for transmission to the remote client coding engine.

Systems and methods for integrated graphics rendering are disclosed. In certain embodiments, the systems and methods utilize a graphics engine, a video encoding engine, and remote client coding engine to render graphics over a network. The systems and methods involve the generation of per-pixel motion vectors, which are converted to per-block motion vectors at the graphics engine. The graphics engine injects these per-block motion vectors into a video encoding engine, such that the video encoding engine may convert those vectors into encoded video data for transmission to the remote client coding engine.

A method for video processing includes: refining motion information of a video block by using a multi-step refinement processing, multiple refined motion vectors (MVs) of the video block being derived iteratively in respective steps of the multi-step refinement processing, and performing a video processing on the video block based on the multiple refined MVs of the video block.

An example device for coding video data determines for a first block of the video data whether to use a sub-block merge mode. Based on the determination not to use the sub-block merge mode for the first block, the device determines whether to use a merge mode with blending for the first block. Based on the determination to use the merge mode with blending for the first block, the device codes the first block with the merge mode with blending.

Systems and methods are disclosed for compressing a target video. A computer-implemented method may use a computer system that include one or more physical computer processors and non-transient electronic storage. The computer-implemented method may include: obtaining the target video, extracting one or more frames from the target video, and generating an estimated optical flow based on a displacement of pixels between the one or more frames. The one or more frames may include one or more of a key frame and a target frame.