Systems and methods are described for video coding using affine motion models with adaptive precision. In an example, a block of video is encoded in a bitstream using an affine motion model, where the affine motion model is characterized by at least two motion vectors. A precision is selected for each of the motion vectors, and the selected precisions are signaled in the bitstream. In some embodiments, the precisions are signaled by including in the bitstream information that identifies one of a plurality of elements in a selected predetermined precision set. The identified element indicates the precision of each of the motion vectors that characterize the affine motion model. In some embodiments, the precision set to be used is signaled expressly in the bitstream; in other embodiments, the precision set may be inferred, e.g., from the block size, block shape or temporal layer.

The present disclosure relates to motion vector refinement. As a first step, an initial motion vector and a template for the block are obtained. Then, the refinement of the initial motion vector is determined by template matching with said template in a search space. The search space is located on a position given by the initial motion vector and includes one or more fractional sample positions, wherein each of fractional sample positions belonging to the search space is obtained by interpolation filtering with a filter of a predefined tap-size assessing integer samples only within a window, said window being formed by integer samples accessible for the template matching in said search space.

The present disclosure relates to a computer-implemented method for processing video data. The method comprises receiving a user input corresponding to a first picture of the video data, generating, based on the user input, prediction information of the first picture with respect a reference picture of the video data, and encoding the first picture using the prediction information.

The present disclosure relates to a computer-implemented method for processing video data. The method comprises receiving a user input corresponding to a first picture of the video data, generating, based on the user input, prediction information of the first picture with respect a reference picture of the video data, and encoding the first picture using the prediction information.

Systems, methods, and computer-readable media are provided for updating history-based motion vector tables. In some examples, a method can include obtaining one or more blocks of video data; determining a first motion vector derived from a first control point of a block of the one or more blocks, the block being coded using an affine motion mode; determining a second motion vector derived from a second control point of the block; based on the first motion vector and the second motion vector, estimating a third motion vector for a predetermined location within the block; and populating a history-based motion vector predictor (HMVP) table with the third motion vector.

The present disclosure provides video decoding method. An exemplary method includes: decoding a first parameter for a coding unit from a bitstream, and determining a candidate for the coding unit based on the first parameter; determining a value of a second parameter associated with the coding unit based on a value of a second parameter associated with the candidate, wherein the second parameter indicates whether a bi-directional prediction correction is enabled; and in response to the value of the second parameter associated with the coding unit indicating the bi-directional prediction correction being enabled, performing the bi-directional prediction correction on the coding unit.

In a method and a device for encoding or decoding an image according to the present invention, motion information for bidirectional prediction of a current block may be derived on the basis of an inter mode previously defined in the device for encoding or decoding an image, and inter prediction may be performed on the current block on the basis of the motion information, wherein the motion information for bidirectional prediction is adjusted to be motion information for unidirectional prediction according to the predefined inter mode.

In a method and a device for encoding or decoding an image according to the present invention, motion information for bidirectional prediction of a current block may be derived on the basis of an inter mode previously defined in the device for encoding or decoding an image, and inter prediction may be performed on the current block on the basis of the motion information, wherein the motion information for bidirectional prediction is adjusted to be motion information for unidirectional prediction according to the predefined inter mode.

Methods and apparatus for video processing are disclosed. The processing may include video encoding, video decoding, or video transcoding. One example method includes performing a conversion between a video including a picture including one or more slices and a bitstream of the video. The conversion conforms to a rule that specifies that whether a deblocking filter is applied to the one or more slices referring to a picture parameter set is based at least on a first syntax element included in the picture parameter set. The first syntax element indicates whether the deblocking filter is disabled for the picture.

Embodiments of the present application provide an inter prediction method, an encoder, a decoder, and a storage medium. The method comprises: determining a prediction mode parameter of a current block; when the prediction mode parameter indicates that the current block determines an inter prediction value by using a geometrical partition mode (GPM), constructing a merge candidate list of the current block; constructing a GPM motion information candidate list according to first motion information in the merge candidate list of the current block; and determining an inter prediction value of the current block according to the GPM motion information candidate list.