Abstract: This disclosure discloses a method for obtaining a candidate motion vector list, an apparatus, an encoder, and a decoder. The method for obtaining a candidate motion vector list comprises: when a first candidate picture block is encoded/decoded and an inter prediction mode is used, determining whether a reference picture of the first candidate picture block is the same as a reference picture of a current block; and constructing a candidate motion vector list of the current block based on a determining result; when the reference picture of the first candidate picture block is different from the reference picture of the current block, the MV of the first candidate picture block is not used to construct the list. Implementing this disclosure can reduce complexity of a motion information derivation process, and improve coding efficiency.

Abstract: A method of determining one or more candidate prediction modes, the method comprises deriving, by a processor, a first indicator by parsing a bitstream, wherein the first indicator specifies whether any affine model is a candidate motion model for an image block in a preset area; determining, by the processor, that the first indicator is set to 1; deriving, by the processor and based on the determination that the first indicator is set to 1, a second indicator by parsing the bitstream, wherein the second indicator specifies whether a 6-parameter affine model is a candidate motion model for the image block; and determining, by the processor, one or more candidate prediction modes for the image block based on the first indicator and the second indicator.

Abstract: Technologies for inter prediction for a block in a video are provided. In one example, a method includes: parsing a bitstream to obtain a syntax element, where the syntax element includes at least an index of optimal candidate motion information of a current block; determining, based on the syntax element, to construct a first list or a second list for the current block, where the first list is a block-based candidate motion information list, and the second list is a subblock-based candidate motion information list; determining optimal motion information from the first list or the second list based on the index; and predicting the current block based on the optimal motion information. In this method, the block-based candidate motion information list and the subblock-based candidate motion information list are distinguished from each other. This effectively reduces transmission costs of the optimal candidate motion information.

Abstract: A video encoder, a video decoder, and a corresponding method are provided. The method includes: parsing a bitstream to obtain an index, where the index indicates a target candidate motion vector group of a current coding block; determining the target candidate motion vector group in an affine candidate motion vector list based on the index, where the affine candidate motion vector list includes at least a first candidate motion vector group, the first candidate motion vector group is obtained based on a first group of control points of a first neighboring affine coding block, and the first group of control points is determined based on a CTU located relative to the current coding block, wherein the first neighboring affine coding block is located in the CTU; and predicting a predicted sample value of the current coding block based on the target candidate motion vector group.

Abstract: A method includes: parsing a bitstream to obtain an index value of a candidate motion vector list; constructing the candidate motion vector list, where the candidate motion vector list includes candidate motion vectors of K control points of a current block, the candidate motion vectors of the K control points are obtained based on a 2N-parameter affine transform model used for a neighboring block of the current block, N, K are integers greater than or equal to 2 and less than or equal to 4, and N is not equal to K; determining, in the candidate motion vector list, target candidate motion vectors of the K control points based on the index value; and obtaining a predicted motion vector of each subblock of the current block based on the target candidate motion vectors of the K control points. It helps improve coding efficiency in an audio and video coding process.

Abstract: This application provides a motion vector obtaining method and apparatus. The method includes: determining a target offset vector of a block and identifier information of a target picture, wherein the block comprises at least one sub-block; determining a location of the sub-block; determining, as a target location coordinate value of a collocated sub-block, a location coordinate value obtained by performing a clipping operation on an initial location coordinate value in a range, wherein the initial location coordinate value is based on the location of the sub-block and the target offset vector; and obtaining a motion vector of the sub-block based on a motion vector corresponding to the target location coordinate value. Thus, a range of the target offset vector is limited, so that a quantity of memory read times can be reduced in a process of obtaining the motion vector of the collocated sub-block.

Abstract: Embodiments of this application relate to the field of video picture coding technologies, and disclose a bidirectional inter prediction method and apparatus, to improve coding efficiency. The method includes: obtaining indication information, where the indication information is used to indicate that second motion information is determined based on first motion information, the first motion information is motion information of a current picture block in a first direction, and the second motion information is motion information of the current picture block in a second direction; obtaining the first motion information; determining the second motion information based on the first motion information; and determining prediction samples of the current picture block based on the first motion information and the second motion information.

Abstract: An image encoding method includes: determining N encoded units from adjacent encoded units of a to-be-encoded unit according to a first preset rule, where a motion prediction mode of the N encoded units is the same as that of the to-be-encoded unit; generating an nth motion vector group by using a first preset algorithm and based on a motion vector of an nth encoded unit; determining, from obtained N motion vector groups according to a second preset rule, one motion vector group as an optimal motion vector group; determining a prediction sample value of each sample unit in the to-be-encoded unit by using a second preset algorithm and based on the optimal motion vector group; and encoding a prediction residual of each sample unit and an index identifier of the optimal motion vector group, to obtain a bitstream corresponding to the to-be-encoded unit.

Abstract: An image encoding method includes: determining N encoded units from adjacent encoded units of a to-be-encoded unit according to a first preset rule, where a motion prediction mode of the N encoded units is the same as that of the to-be-encoded unit; generating an nth motion vector group by using a first preset algorithm and based on a motion vector of an nth encoded unit; determining, from obtained N motion vector groups according to a second preset rule, one motion vector group as an optimal motion vector group; determining a prediction sample value of each sample unit in the to-be-encoded unit by using a second preset algorithm and based on the optimal motion vector group; and encoding a prediction residual of each sample unit and an index identifier of the optimal motion vector group, to obtain a bitstream corresponding to the to-be-encoded unit.

Abstract: The invention relates to a loop filter apparatus for processing a reconstructed picture of a video stream into a filtered reconstructed picture that includes a plurality of samples. The loop filter apparatus includes processing circuitry configured to apply a first partition to the reconstructed picture or at least a portion thereof so as to partition the reconstructed picture into a plurality of sample blocks and to apply a respective noise suppression filter to the one or more sample blocks to obtain one or more filtered sample blocks. The one or more sample blocks are defined by an application map, the noise suppression filter depends on the application map, and the application map partitions the reconstructed picture into a plurality of regions The processing circuitry is further configured to generate the filtered reconstructed picture. Moreover, the invention relates to a corresponding loop filtering method.

Abstract: An apparatus comprises: a memory; and a processor coupled to the memory and configured to: obtain candidate MVs corresponding to neighboring blocks that neighbor a current block in a video frame, generate a candidate list of the candidate MVs, select final MVs from the candidate list, and apply constraints to the final MVs or a transformation to obtain constrained MVs. An apparatus comprises: a memory; and a processor coupled to the memory and configured to: obtain candidate MVs corresponding to neighboring blocks that neighbor a current block in a video frame, generate a candidate list of the candidate MVs, apply constraints to the candidate MVs or a transformation to obtain constrained MVs, and select final MVs from the constrained MVs.

Abstract: A picture prediction method is provided, which includes: obtaining initial motion information of a current picture block; determining, based on a matching cost criterion, that positions of a pair of reference blocks are a position of a target forward reference block of the current picture block and a position of a target backward reference block of the current picture block, where positions of each pair of reference blocks include a position of a forward reference block and a position of a backward reference block; and for the positions of each pair of reference blocks, a first position offset and a second position offset are in a mirror relationship; and obtaining a predicted value of a pixel value of the current picture block based on a pixel value of the target forward reference block and a pixel value of the target backward reference block.

Abstract: A video data inter prediction method is provided, which includes: determining a candidate motion information list of a current picture block, where the candidate motion information list includes at least one first candidate motion information group, at least one second candidate motion information group, the first candidate motion information group is a motion information group determined based on motion information of preset locations on a first neighboring picture block of the current picture block and a motion model of the first neighboring picture block, the second candidate motion information group is a set of motion information of at least two sample locations that are respectively neighboring to at least two preset locations on the current picture block; determining target motion information from the candidate motion information list; and performing inter prediction on the current picture block based on the target motion information.

Abstract: A video coding mechanism is disclosed. The mechanism includes selecting a split mechanism to split a coding unit (CU) into sub-CUs for application of one or more transform units (TUs), the selection of the split mechanism based on comparing a CU width to a max TU width and comparing a CU height to a max TU height. The selected split mechanism is applied to the CU to obtain sub-CUs. A residual of one of the sub-CUs is determined. The residual includes a difference between sample values for the sub-CU and prediction samples for the sub-CU. The TUs are applied to transform the residual of the CU based on results of the selected split mechanism. A transformed residual for the CU is encoded into a bitstream.

Abstract: An image encoding method includes: determining N encoded units from adjacent encoded units of a to-be-encoded unit according to a first preset rule, where a motion prediction mode of the N encoded units is the same as that of the to-be-encoded unit; generating an nth motion vector group by using a first preset algorithm and based on a motion vector of an nth encoded unit; determining, from obtained N motion vector groups according to a second preset rule, one motion vector group as an optimal motion vector group; determining a prediction sample value of each sample unit in the to-be-encoded unit by using a second preset algorithm and based on the optimal motion vector group; and encoding a prediction residual of each sample unit and an index identifier of the optimal motion vector group, to obtain a bitstream corresponding to the to-be-encoded unit.

Abstract: An inter prediction method includes parsing, by a processor, a bitstream to obtain a location of a target adjacent image block of a current image block. The method further includes obtaining a preset correspondence between an adjacent image block location and a motion vector precision, wherein in the preset correspondence, locations of at least two adjacent image blocks correspond to different motion vector precisions. The method further includes determining, based on the location of the target adjacent image block and the preset correspondence, a target motion vector precision corresponding to the target adjacent image block. The method further includes determining a motion vector predictor of the current image block based on the location of the target adjacent image block and the target motion vector precision.

Abstract: Disclosed is a mechanism for selecting an interpolation filter for use in conjunction with an affine block in video coding. A motion vector is determined for a sub-block of the affine block based on control points. A sub-block size of the sub-block is also determined. The interpolation filter is selected for application to a reference block corresponding to the sub-block. The interpolation filter is selected based on the sub-block size. The motion vector of the sub-block and an offset of a current sample of the sub-block are employed to determine a reference sample at the reference block. This includes applying the interpolation filter to the reference block to determine the reference sample when the motion vector at the offset points to a fractional position at the reference block. The reference samples are employed to determine residual information in order to encode the affine block.

Abstract: A method includes obtaining a first motion vector of a motion compensation unit included in an affine code block. The method also includes determining a second motion vector based on the first motion vector, where a precision of the second motion vector matches a motion vector precision of a storage unit corresponding to the motion compensation unit. The method further includes determining a third motion vector based on the second motion vector, where there is a preset correspondence between the third motion vector and the second motion vector, and the third motion vector is used for subsequent encoding/decoding processing.

Abstract: A picture prediction method includes: determining two pixel samples in a current picture block, and determining a candidate motion information unit set corresponding to each of the two pixel samples; determining a merged motion information unit set i including two motion information units; and predicting a pixel value of the current picture block by using an atone motion model and the merged motion information unit set i.

Abstract: A picture prediction method and a related apparatus are disclosed. A picture prediction method includes: determining K1 pixel samples in a picture block x, and determining a candidate motion information unit set corresponding to each pixel sample in the K1 pixel samples, where the candidate motion information unit set corresponding to each pixel sample includes at least one candidate motion information unit; determining a merged motion information unit set i including K1 motion information units, where each motion information unit in the merged motion information unit set i is selected from at least a part of motion information units in candidate motion information unit sets corresponding to different pixel samples in the K1 pixel samples; and predicting a pixel value of the picture block x by using a non-translational motion model and the merged motion information unit set i.