Abstract: Decoding a current block includes obtaining at least one of a maximum motion vector (MV) precision or a minimum MV precision for a group of blocks. The group of blocks includes the current block. A block-level MV precision for decoding the current block is obtained. The block-level MV precision is such that it is limited by the at least one of the maximum MV precision or the minimum MV precision. An MV for the current block is decoded using the block-level MV precision. A prediction block is obtained for the block using the MV.

Abstract: Motion vector (MV) coding using an MV precision is described. An MV class of a motion vector difference (MVD) is decoded. Whether to omit decoding least significant bits of offset bits of an integer portion of the MVD is determined using a MV precision. The integer portion is obtained using at least some decoded offset bits and the least significant bits of the integer portion. Whether to omit decoding least significant bits of fractional bits of a fractional portion is determined using the MV precision. The fractional portion is obtained using at least some decoded fractional bits and the least significant bits of the fractional portion. The MVD is obtained using at least the integer portion and the fractional portion. An MV for the current block is obtained using the MVD.

Abstract: A method of decoding a coded video bitstream implemented by a video decoder is provided. The method includes the video decoder determining whether a gradual decoding refresh (GDR) picture in the coded video bitstream is an initial picture in decoding order or the initial picture following an end of sequence (EOS) network abstraction layer (NAL) unit in the decoding order; setting a flag to a value to prevent the GDR picture from being output when the GDR picture is the initial picture in decoding order or the initial picture following the EOS NAL unit in the decoding order; decoding the GDR picture; and storing the GDR picture in a decoded picture buffer (DPB).

Abstract: A method of decoding a coded video bitstream implemented by a video decoder is provided. The method includes the video decoder determining whether a value for a first flag is provided by an external input; setting a first flag equal to the value provided by the external input and a second flag equal to the value of the first flag to prevent a gradual decoding refresh (GDR) picture from being output when the value for the first flag is provided by the external input; decoding the GDR picture; and storing the GDR picture in a decoded picture buffer (DPB).

Abstract: A method of decoding is provided. The method includes receiving a video bitstream including a picture unit (PU), where the PU includes a picture header (PH) network abstraction layer (NAL) unit preceding a first video coding layer (VCL) NAL unit, and decoding a coded picture from the PU to obtain a decoded picture.

Abstract: A method of coding, implemented by a decoding device, includes obtaining a bitstream, wherein at least one bit in the bitstream represents a syntax element for a current block, wherein the syntax element specifies the clipping index of the clipping value for an adaptive loop filter (ALF); parsing the bitstream to obtain a value of the syntax element for the current block, wherein the syntax element is coded using a fixed length code; applying adaptive loop filtering on the current block, based on the value of the syntax element for the current block. Herein fixed length code means that all possible values of the syntax element are signaled using the same number of bits.

Abstract: A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising a slice and a luma mapping with chroma scaling (LMCS) adaptation parameter set (APS) including LMCS parameters. The mechanism further includes determining that the LMCS APS is referenced in data related to the slice. The mechanism further includes decoding the slice using LMCS parameters from the LMCS APS based on the reference to the LMCS APS. The mechanism further includes forwarding the slice for display as part of a decoded video sequence.

Abstract: A partitioning method comprises determining whether a current block of a picture is a boundary block and whether the size of the current block is larger than a minimum allowed quadtree leaf node size; and if the current block is the boundary block and the size of the current block is not larger than the minimum allowed quadtree leaf node size (MinQTSize), applying forced binary tree (BT) partitioning to the current block. A method comprises making a determination that a current block of a picture is a boundary block and that a size of the current block is less than or equal to a minimum allowed quadtree (QT) leaf node size (MinQTSize); and applying, in response to the determination, forced binary tree (BT) partitioning to the current block.

Abstract: The present disclosure provides methods and devices of intra predicting a block of a picture. The method comprises for a sample of the block: obtaining a predicted sample value from one or more reference sample values by performing intra-prediction using a DC intra-prediction mode; multiplying the predicted sample value by a sample weighting factor to produce a weighted predicted sample value; adding an additional value to the weighted predicted sample value to produce a non-normalized predicted sample value; and normalizing the non-normalized predicted sample value by an arithmetic right shift; wherein the sample weighting factor is ((2<<p)?wL?wT), wherein p is a parameter of the sample weighting factor, wL is a horizontal weighting factor, and wT is a vertical weighting factor.

Abstract: A method of decoding a coded video bitstream implemented by a video decoder is provided. The method includes the video decoder receiving the coded video bitstream, the coded video bitstream containing a gradual decoding refresh (GDR) flag corresponding to a coded video sequence (CVS); determining, by the video decoder, whether a GDR picture is present in the CVS based on a value of the GDR flag; initiating, by the video decoder, decoding of the CVS at the GDR picture when the value of the GDR flag indicates that the GDR picture is present; and generating, by the video decoder, an image according to the CVS as decoded. A corresponding method of encoding implemented by a video encoder is also disclosed.

Abstract: An image prediction method, apparatus, and system, a device, and a storage medium are provided. The method includes: (401) obtaining a split mode of a current node, where the current node is an image block in a coding tree unit in a current image; (402) determining, based on the split mode of the current node and a size of the current node, whether the current node satisfies a first condition; and (403) when it is determined that the current node satisfies the first condition, performing intra prediction on all coding blocks belonging to the current node, to obtain predictors of all the coding blocks belonging to the current node.

Abstract: A method of decoding includes receiving the coded video bitstream, the coded video bitstream containing reference picture lists; obtaining reference pictures for a current picture from the reference picture lists; setting a motion vector refinement flag to a first value to enable motion vector refinement for a current block of the current picture when the reference pictures are in a same layer as the current picture; setting the motion vector refinement flag to a second value to disable the motion vector refinement for the current block of the current picture when the reference pictures are in a different layer than the current picture; and refining a motion vector corresponding to the current block when the motion vector refinement flag is set to the first value.

Abstract: The present disclosure provides methods and devices of processing a block according to a merge candidate list, the method comprising: constructing a first list according to motion information of neighboring blocks of a current block; obtaining prediction information of the current block; when the prediction information of the current block indicates that a sub-block prediction is applied to the current block, obtaining a uni-prediction candidate for the current block according to the first list; using, the uni-prediction candidate for the current block to perform inter prediction of the current block. According to embodiment of the present disclosure, the regular merge list can be directly used and there is no need to explicitly generate the uni-prediction merge candidate list for sub-block prediction.

Abstract: Encoding and decoding using warped reference list includes generating a reconstructed frame from an encoded bitstream by, for decoding a current block for the reconstructed frame, obtaining a dynamic reference list, obtaining a warped reference list, decoding a warped reference list index value, obtaining optimal predicted warped model parameters from the warped reference list in accordance with the index value, decoding differential warped model parameters, obtaining, as optimal warped model parameters, a result of adding the optimal predicted warped model parameters and the differential warped model parameters, obtaining predicted block data in accordance with the optimal warped model parameters, decoding residual block data, and obtaining, as decoded block data for the current block, a result of adding the residual block data and the predicted block data.

Abstract: A decoding method and a decoder for decoding a current block of a video frame is provided, wherein the decoding method comprises determining a list of Most Probable Modes (MPMs) for the current block. When at least one condition is satisfied, the list of MPMs includes a DC mode, a Vertical mode, a Horizontal mode, an intra prediction mode corresponding to a value of the Vertical mode with a first offset, and an intra prediction mode corresponding to the value of the Vertical mode with a second offset. The decoding method further includes obtaining a MPM flag and a MPM index for the current block from a bitstream of the video, and obtaining an intra prediction mode for the current block for reconstructing the current block.

Abstract: An example device for filtering decoded video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: decode a picture of video data; code a value for a syntax element representing a neural network model to be used to filter a portion of the decoded picture, the value representing an index into a set of pre-defined neural network models, the index corresponding to the neural network model in the set of pre-defined neural network models; and filter the portion of the decoded picture using the neural network model corresponding to the index.

Abstract: An example device for filtering decoded video data includes one or more processors configured to execute a neural network filtering unit to: receive data from one or more other units of the device, the data from the one or more other units of the device being different than data for a decoded picture of video data, and wherein to receive the data from the one or more other units of the device, the one or more processors are configured to execute the neural network filtering unit to receive boundary strength data from a deblocking unit of the device; determine one or more neural network models to be used to filter a portion of the decoded picture; and filter the portion of the decoded picture using the one or more neural network models and the data from the one or more other units of the device, including the boundary strength data.

Abstract: A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising a first header parameter set (HPS) containing a first type of coding tool parameters, a second HPS containing a second type of coding tool parameters, a slice header, and a slice associated with the slice header. The mechanism further includes determining that the slice header contains a first reference to the first HPS and a second reference to the second HPS. The mechanism further includes decoding the slice using the first type of coding tool parameters and the second type of coding tool parameters based on the determination that the slice header contains the first reference and the second reference. The mechanism further includes forwarding the slice for display as part of a decoded video sequence.

Abstract: A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising a slice and a plurality of adaptation parameter sets (APSs) including a plurality of APS types, wherein each APS includes an APS identifier (ID), and wherein APS IDs for the APS types are assigned in sequence over a plurality of different value spaces. The mechanism further includes decoding the slice using parameters from the plurality of APSs. The mechanism further includes forwarding the slice for display as part of a decoded video sequence.

Abstract: It is provided a method of prediction coding of a current block, comprising: obtaining an intra prediction mode of a left neighbor block of the current block and an intra prediction mode of an above neighbor block of the current block; constructing a Most Probable Mode (MPM) list of intra prediction modes for the current block, the MPM list comprising at least 5 entries of intra prediction modes as follows: {ang, 2+((ang+61)%64), 2+((ang?1)%64), 2+((ang+60)%64), 2+((ang) %64)} when at least a first condition is fulfilled, where ang represents the intra prediction mode of the left neighbor block or the intra prediction mode of the above neighbor block.