Abstract: A method of encoding a motion vector predictor index, in particular a Merge index, comprises generating a list of motion vector predictor candidates, in particular merge candidates. The list includes an ATMVP candidate. One of the motion vector predictor candidates in the list is selected. A motion vector predictor index for the selected motion vector predictor candidate is generated using CABAC coding. One or more bits of the motion vector predictor index are bypass CABAC coded. For example, only the first bit of the motion vector predictor index is CABAC coded using a single context.

Abstract: Embodiments of video coding systems and methods are described for reducing coding latency introduced by decoder-side motion vector refinement (DMVR). In one example, two non-refined motion vectors are identified for coding of a first block of samples (e.g. a first coding unit) using bi-prediction. One or both of the non-refined motion vectors are used to predict motion information for a second block of samples (e.g. a second coding unit). The two non-refined motion vectors are refined using DMVR, and the refined motion vectors are used to generate a prediction signal of the first block of samples. Such embodiments allow the second block of samples to be coded substantially in parallel with the first block without waiting for completion of DMVR on the first block. In additional embodiments, optical-flow-based techniques are described for motion vector refinement.

Abstract: A method of decoding motion information includes: identifying a type of omission motion information not included in a bitstream from among a plurality of pieces of motion information used to decode a current block that is inter predicted; obtaining the omission motion information by using a predetermined method; and decoding the current block based on the plurality of pieces of motion information including the obtained omission motion information.

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.

Abstract: A set of tensor-product B-Spline (TPB) basis functions is determined. A set of selected TPB prediction parameters to be used with the set of TPB basis functions for generating predicted image data in mapped images from source image data in source images of a source color grade is generated. The set of selected TPB prediction parameters is generated by minimizing differences between the predicted image data in the mapped images and reference image data in reference images of a reference color grade. The reference images correspond to the source images and depict same visual content as depicted by the source images. The set of selected TPB prediction parameters is encoded in a video signal as a part of image metadata along with the source image data in the source images. The mapped images are caused to be reconstructed and rendered with a recipient device of the video signal.

Abstract: A method of coding implemented by a decoding device, comprising obtaining a bitstream; obtaining a value of an indicator for a current block according to the bitstream; obtaining a value of a first parameter for the current block and a value of a second parameter for the current block, according to the value of the indicator and a predefined lookup table; obtaining a value of a sample distance for a sample which is located in the current block, according to the value of the first parameter and the value of the second parameter; obtaining a prediction value for the sample, according to the value of the sample distance for the sample.

Abstract: Disclosed are methods and apparatuses for decoding an image. A method includes receiving a bitstream obtained by encoding the image; dividing a first coding block into a plurality of second coding blocks; generating a prediction block of a second coding block based on syntax information obtained from the bitstream; and reconstructing the second coding block based on the prediction block and a residual block of the second coding block, the residual block being obtained by performing a dequantization and an inverse-transform on quantized transform coefficients from the bitstream. The first coding block has a recursive division structure. The first coding block is divided based on at least one of a quad tree division, a binary tree division or a triple tree division.

Abstract: Devices, systems and methods for encoding and decoding digital video using a look-up tables (LUTs) containing motion candidates are described. In a representative aspect, a method of video processing includes maintaining one or more tables, wherein at least one table of the one or more tables is associated with one or more entries, deriving, based on a first set of motion candidates in the at least one table, a second set of motion candidates, and performing, based on the second set of motion candidates, a conversion between a current block of a video and a bitstream representation of the video.

Abstract: Difference calculation based on partial position is described. In a representative aspect, a method of video processing comprising: calculating, during a conversion between a current block of video and a bitstream representation of the current block, differences between two reference blocks associated with the current block or differences between two reference sub-blocks associated with a sub-block within the current block based on representative positions of the reference blocks or representative positions of the reference sub-blocks; and performing the conversion based on the differences.

Abstract: The method includes receiving data representing a first frame of video content including a plurality of frames and determining, for at least one object in a first frame, an object type and position in the first frame. The method further includes determining a number of frames N to skip over based on the type and position of the object in the first frame and the type and position of one or more objects in one or more prior frames, and for providing the N+1 frame, and not the skipped-over frames.

Abstract: A device and method for coding video data is described. The device may generate filtered samples by performing, in a predicted samples domain, interpolation filtering and a second filtering from a group of one or more of: an adaptive filter, a domain transform filter, a scaler, or a local illumination compensation (LIC). The device may generate one or more of: residual data based on the filtered samples, or reconstructed samples based on the filtered samples; and code the video data based on one or more of the residual data or the reconstructed samples.

Abstract: An apparatus for video decoding includes processing circuitry. The circuitry can be configured to receive a current block that is affine coded and included in a current coding tree unit (CTU), and determine an inherited affine candidate based on regular motion information of two minimum blocks in a rightmost column of minimum blocks of a left neighboring CTU of the current CTU when the current block is adjacent to a left boundary of the current CTU.

Abstract: An apparatus for video decoding includes processing circuitry. The processing circuitry determines a string vector for a current string in a current coding tree unit (CTU). The string vector points to a reference string for the current string. The processing circuitry determines that the string vector satisfies a requirement for an allowance of a partial overlapping of the current string and the reference string, and then reconstructs the current string based on the reference string.

Abstract: The present disclosure provides a video picture coding method, a video picture decoding method, a coding device, and a decoding device. The method includes: determining a distance between control points for an affine picture block; determining a motion vector difference for the affine picture block, motion vectors of the control points being used to determine the motion vector difference; and performing coding processing on the affine picture block over a size that includes a horizontal length and a vertical length, wherein the horizontal length and the vertical length vary based on the distance between the control points, the motion vector difference, and a motion vector precision.

Abstract: Disclosed are methods and apparatuses for decoding an image. A method includes receiving a bitstream obtained by encoding the image; dividing a first coding block into a plurality of second coding blocks; generating a prediction block of a second coding block based on syntax information obtained from the bitstream; and reconstructing the second coding block based on the prediction block and a residual block of the second coding block, the residual block being obtained by performing a dequantization and an inverse-transform on quantized transform coefficients from the bitstream. The first coding block has a recursive division structure. The first coding block is divided based on at least one of a quad tree division, a binary tree division or a triple tree division.

Abstract: A method of decoding an image according to an embodiment includes: when a size of a current block in the image is equal to or greater than a certain size, determining a candidate list including, as a candidate, a first reference block indicated by a temporal motion vector; when the first reference block is selected from among candidates included in the candidate list, determining motion vectors of sub-blocks in the current block by using motion vectors obtained from the first reference block; and reconstructing the current block based on sample values of a second reference block indicated by the motion vectors of the sub-blocks.

Abstract: Systems, methods, and instrumentalities for affine motion estimation for affine model-based video coding may be disclosed herein. A first motion vector (MV) set including one or more MVs may be derived for a first coding block. The MVs may be control point MVs (CPMVs) and the MVs may be derived by performing affine motion estimation (ME) associated with the first coding block. The first MV set may be added to a recently-estimated MV list. A head of the recently-estimated MV list may be set to the first MV set. The recently-estimated MV list may be empty or may contain one or more previously-added MV sets.

Abstract: Disclosed are methods and apparatuses for decoding an image. A method includes receiving a bitstream obtained by encoding the image; dividing a first coding block into a plurality of second coding blocks; generating a prediction block of a second coding block based on syntax information obtained from the bitstream; and reconstructing the second coding block based on the prediction block and a residual block of the second coding block, the residual block being obtained by performing a dequantization and an inverse-transform on quantized transform coefficients from the bitstream. The first coding block has a recursive division structure. The first coding block is divided based on at least one of a quad tree division, a binary tree division or a triple tree division.

Abstract: A method of performing bi-directional optical flow, BDOF, processing for a video sequence of images, with each image including a plurality of blocks with bidirectional-predicted inter coding blocks, BPICBs. The method includes obtaining a shifted pair of refinement parameters per a subblock of a bidirectional-predicted inter coding block, wherein the shifted pair of refinement parameters includes a shifted first refinement parameter and a shifted second refinement parameter.

Abstract: An image decoding method includes: deriving a refined L0 motion vector and a refined L1 motion vector by applying decoder-side motion vector refinement (DMVR) based on an L0 motion vector and an L1 motion vector of a current block, deriving prediction samples for the current block based on L0 prediction samples derived based on the refined L0 motion vector and L1 prediction samples derived based on the refined L1 motion vector, and generating reconstructed samples for the current block based on the prediction samples. The L0 prediction samples are derived based on an L0 reference picture and the refined L0 motion vector, and the L1 prediction samples are derived based on an L1 reference picture and the refined L1 motion vector, and deriving the prediction samples comprises determining whether to apply bi-directional optical flow (BDOF) process based on a first POC difference and a second POC difference are the same.

Abstract: A method of video processing is provided to include: deciding a coding mode used for representing a current video block of a video in a coded representation of the video; and coding the current video block into the coded representation according to the coding mode, wherein use of alternative half-pel accuracy filters in addition to a default half-pel accuracy filter for representing motion information is disabled for the current video block due to use of the coding mode.

Abstract: A video decoder can be configured to determine that a current block in a current picture of the video data is coded in an affine prediction mode; determine one or more control-point motion vectors (CPMVs) for the current block; identify an initial prediction block for the current block in a reference picture using the one or more CPMVs; determine a current template for the current block in the current picture; and determine an initial reference template for the initial prediction block in the reference picture; and perform a motion vector refinement process to determine a modified prediction block based on a comparison of the current template to the initial reference template.

Abstract: Motion vectors (MVs) are used as predictors for prediction of an image for a current coding unit (CU) within a current video frame. The MVs are from a list of motion vector candidates (MVCs), which is generated. The list includes MVs determined from a first or second pattern, each pattern specifying MVC positions. The first MV positions are within a current video frame, while the second MV positions are for a video frame different from the current frame. The MVC list is generated for a current CU with the MV positions being relative to a position of the current CU. In particular, the MVC list is generated in dependence on a size of the current CU and a size of a grid specifying a minimum distance between two MV positions. One or more MVs as specified by the MV positions of said pattern are included into the MVC list.

Abstract: A video decoding method performed by a video decoding apparatus, according to the present document, comprises the steps of: acquiring general constraint information from a bitstream; parsing, from the bitstream, a flag indicating whether or not the general constraint information includes information about constraints to which output layer sets conform; parsing the information about the constraints in the general constraint information on the basis of the flag; and decoding a current picture on the basis of the information about the constraints, wherein the general constraint information includes number information and alignment information about the constraints, and, within the general constraint information, the alignment information may be present after the number information.

Abstract: An encoder calculates a first local encoding parameter for a first block of video content based on one or more local metrics. The encoder modifies the first local encoding parameter based on one or more second local encoding parameters for one or more second blocks of video content that are adjacent to the first block of video content. The encoder then encodes the first block using the modified first local encoding parameter. In some cases, the local encoding parameters are quantization parameters used to quantize values of pixels or compression parameters used to compress values of the pixels. The local metric can include one or more of a target bit rate, a texture complexity, a contrast, an indicator of motion in the first block, and an importance map.

Abstract: Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes receiving circuitry and processing circuitry. In some embodiments, processing circuitry decodes, prediction information for a block in an I slice from a coded video bitstream, and determines, whether an intra block copy (IBC) mode is possible for the block in the I slice. In response to a slice type parameter indicating I slice and at least a width or height of the block being greater than 64, the processing circuitry sets a current mode type parameter to MODE_TYPE_INTRA. Further, in an embodiment, the processing circuitry decodes a flag that indicates whether a skip mode is applied on the block from the coded video bitstream. Then, the processing circuitry reconstructs the block at least partially based on the flag.

Abstract: A first motion vector and a second motion vector are determined for a first block in a current picture of a video, where the first motion vector is indicative of a first reference block in a first picture, and the second motion vector is indicative of a second reference block in a second picture. A bilateral template is generated based on a weighted combination of the first reference block and the second reference block. A refined first motion vector is determined based on the bilateral template and a first set of reference blocks in the first picture. A refined second motion vector is determined based on the bilateral template and a second set of reference blocks in the second picture. Prediction information of the first block is generated according to (i) the refined first motion vector, (ii) the refined second motion vector, and (iii) a final motion compensation interpolation filter.

Abstract: The disclosure discloses a method for processing video signals and an apparatus therefor. Specifically, the method of processing video signals based on history based motion vector prediction, comprising: configuring a merge candidate list based on a neighboring block to a current block; adding a history based merge candidate of the current block to the merge candidate list when a number of merge candidates included in the merge candidate list is smaller than a first predetermined number; adding a zero motion vector to the merge candidate list when the number of merge candidates included in the merge candidate list is smaller than a second predetermined number; obtaining a merge index indicating a merge candidate used for inter prediction of the current block in the merge candidate list; generating a prediction sample of the current block based on motion information of the merge candidate indicated by the merge index; and updating a history based merge candidate list based on the motion information.

Abstract: The present disclosure describes techniques for coding and decoding video in which a plurality of coding hypotheses are developed for an input pixel block of frame content. Each coding hypothesis may include generation of prediction data for the input pixel block according to a respective prediction search. The input pixel block may be coded with reference to a prediction block formed from prediction data derived according to plurality of hypotheses. Data of the coded pixel block may be transmitted to a decoder along with data identifying a number of the hypotheses used during the coding to a channel. At a decoder, an inverse process may be performed, which may include generation of a counterpart prediction block from prediction data derived according to the hypothesis identified with the coded pixel block data, then decoding of the coded pixel block according to the prediction data.

Abstract: An image decoding method performed by a decoding device according to the present disclosure comprises the steps of: obtaining motion prediction information relating to a current block from a bitstream; generating an affine MVP candidate list for the current block; deriving CPMVPs for CPs of the current block on the basis of the affine MVP candidate list; deriving CPMVDs for the CPs of the current block on the basis of the motion prediction information; deriving CPMVs for the CPs of the current block on the basis of the CPMVPs and the CPMVDs; and deriving prediction samples for the current block on the basis of the CPMVs.

Abstract: Embodiments of this application provide for a video super-resolution processing method. The method includes obtaining encoded information of a coding block in a video stream. The method further includes determining an inter-frame prediction mode of the coding block based on an inter-frame prediction marker included in the encoded information. The method further includes determining a super-resolution pixel block of the coding block based on the inter-frame prediction mode of the coding block and pixel information of a matched coding block identified by a matched coding block index included in the encoded information. The method further includes stitching super-resolution pixel blocks of all coding blocks that belong to a same image frame in the video stream to obtain a super-resolution image. Power consumption can be reduced while an effect of super-resolution processing performed on a single frame of image in a video is ensured.

Abstract: Methods, systems and devices for implementing constraints used in video encoding and video decoding are described. An example method of video processing includes performing a conversion between a video including one or more pictures including one or more slices and a bitstream of the video, wherein the bitstream is organized into a plurality of access units (AUs), AU 0 to AU n, based on a format rule, where n is a positive integer, wherein the format rule specifies a relationship between removal times of each of the plurality of AUs from a coded picture buffer (CPB) during decoding and a number of slices in the each of the plurality of AUs.

Abstract: Decoding a current block includes decoding a subset of quantized transform coefficients of a quantized transform block using a first scan order. A second scan order is determined based on the subset of the quantized transform coefficients. Remaining quantized transform coefficients of the quantized transform block are decoded based on the second scan order. A context model for decoding an intra-prediction mode is determined based on at least the subset of the quantized transform coefficients. The intra-prediction mode is decoded based on the context model. The current block is obtained based on the quantized transform coefficients and the intra-prediction mode.

Abstract: A method includes performing a conversion, according to a rule, between a current slice of a current picture of a video and a bitstream of the video, wherein the rule specifies that a first syntax element of a picture parameter set (PPS) and a second syntax element of the PPS control whether a third syntax element is included in the bitstream, and wherein the first syntax element indicates whether a weighted prediction is enabled for bi-directional slices of coded pictures referring to the PPS, the second syntax element indicates whether information related to the weighted prediction is present in picture headers or slice headers of coded pictures referring to the PPS, and the third syntax element indicates a number of weights associated with a reference picture list 1 of the current slice.

Abstract: A method of video processing comprises determining, for a conversion between a first block of video and a bitstream representation of the first block, a range of motion vector difference (MVD) component associated with the first block, wherein the range of MVD component is [?2M, 2M?1], where M=17; constraining value of the MVD component to be in the range of MVD component; and performing the conversion based on the constrained MVD component.

Abstract: Difference calculation based on partial position is described. In a representative aspect, a method of video processing comprising: calculating, during a conversion between a current block of video and a bitstream representation of the current block, differences between two reference blocks associated with the current block or differences between two reference sub-blocks associated with a sub-block within the current block based on representative positions of the reference blocks or representative positions of the reference sub-blocks; and performing the conversion based on the differences.

Abstract: An image decoding method according to the present disclosure may include the steps of: determining whether a combined prediction mode is applied to a current block; when the combined prediction mode is applied to the current block, obtaining first and second prediction blocks with respect to the current block; and, on the basis of a calculation of a weighted sum of the first and second prediction blocks, obtaining a third prediction block with respect to the current block.

Abstract: The application relates to an encoding and decoding method and apparatus, an encoding-side device, and a decoding-side device. The method includes: if characteristic information of a current block meets a specific condition, determining a first reference block corresponding to the current block according to a first original motion vector of the current block, and determining a second reference block corresponding to the current block according to a second original motion vector of the current block; adjusting the first and second original motion vectors according to a first pixel value of the first reference block and a second pixel value of the second reference block to obtain a first target motion vector corresponding to the first original motion vector and a second target motion vector corresponding to the second original motion vector; encoding or decoding the current block according to the first and second target motion vectors.

Abstract: An image decoding method according to the present document comprises the steps of: acquiring, from a bitstream, reference line index information indicating a reference line to be used for intra prediction of a current block; constructing a most probable mode (MPM) list by deriving candidate intra prediction modes of the current block on the basis of the value of the reference line index information; deriving the intra prediction mode of the current block on the basis of the MPM list; generating prediction samples for the current block on the basis of the intra prediction mode; and generating restoration samples for the current block on the basis of the prediction samples, wherein, on the basis of the case in which the value of the reference line index information is not zero, one of the candidate intra prediction modes is a DC mode and the number of candidate intra prediction modes including the DC mode is 5.

Abstract: A method, computer program, and computer system for encoding or decoding video data, and indicating, with a syntax element, types of slices for all slices of a coded picture, the syntax element being coded using an unsigned integer.

Abstract: The present invention relates to a method for encoding/decoding a video. To this end, the method for decoding a video may include: generating a merge candidate list of a current block including at least one merge candidate corresponding to each of a plurality of reference picture lists; determining at least one piece of motion information by using the merge candidate list; and generating a prediction block of the current block by using the determined at least one piece of motion information.

Abstract: A method and apparatus of encoding or decoding for a coding system, where bi-directional CU (coding unit) weighting (BCW) is enabled for the coding system to allow using multiple pairs of weights, are disclosed. According to this method, a Merge candidate list is generated for the current block, where current bi-directional CU weights for a bi-directional predictor of the current block associated with a target Merge candidate in the Merge candidate list are set to a pre-define pair of weights when the target Merge candidate corresponds to a selected Merge candidate. In another method, current bi-directional CU weights for a bi-directional predictor associated with a target Merge candidate in the Merge candidate list are inherited from the target Merge candidate when the target Merge candidate corresponds to a selected Merge candidate.

Abstract: An example device includes memory configured to store the video data and one or more processors implemented in circuitry and communicatively coupled to the memory. The one or more processors are configured to determine at least one of a temporal candidate or a history-based candidate and determine at least one non-adjacent candidate, wherein the at least one non-adjacent candidate is from a unit that is not adjacent to a current prediction unit (PU). The one or more processors are configured to determine an advanced motion vector predictor (AMVP) candidate list including the at least one of the temporal candidate or the history-based candidate and the at least one non-adjacent candidate. The at least one non-adjacent candidate is added to the AMVP candidate list after the temporal candidate or before the history-based candidate. The one or more processors are configured to code the current PU based on the AMVP candidate list.

Abstract: A transmitting method for transmitting a bitstream to a terminal is provided. The bit stream is generated by coding a current block of a picture and has an index for identifying a motion vector candidate from a motion vector candidate list. The motion vector candidate list is generated and includes motion vector candidates and a value for each motion vector candidate. A second candidate is arranged before a first candidate in the motion vector candidate list. The first candidate is sorted before the second candidate in the motion vector candidate list based on the values of the first and second candidates. The value of the first candidate is higher than the value of the second candidate. For each motion vector candidate, the value is based on a number of times the motion vector candidate is selected as a motion vector predictor for neighboring blocks.

Abstract: An image decoding method according to the present disclosure includes deriving a history-based motion vector prediction (HMVP) buffer for a current block, deriving motion information of the current block based on an HMVP candidate included in the HMVP buffer, generating prediction samples for the current block based on the motion information, and generating reconstructed samples based on the prediction samples, and the HMVP buffer is initialized when processing a first-ordered CTU in a CTU row in which a current CTU is located, and the current block is included in the current CTU.

Abstract: Devices, systems and methods for coding video using one or more tables to store motion information and process subsequent blocks are described. In one aspect, a video coding method is provided to include deriving motion information for a first video block which is coded using an intra block copy mode, wherein one or more candidates of one or more tables are selectively checked during a motion candidate list construction process which is used to derive the motion information for the first video block, wherein each table of the one or more tables includes motion candidates derived from previously coded video blocks that are coded prior to the first video block; and coding, based on the motion information, the first video block.

Abstract: A video coding method and apparatus for codes a video in a data stream using block-based predictive coding by deriving a collection of one or more primitive predictions for a block using a set of primitive prediction modes adapted for predicting blocks of a picture of the video. Each primitive prediction in the collection of primitive predictions is derived using a respective primitive prediction mode from the set of primitive prediction modes. A composite prediction signal for the block is composed by combining primitive predictions from the collection of one or more primitive predictions, and the block is predicted using the composite prediction signal.

Abstract: An image coding method includes: generating a first flag indicating whether or not a motion vector predictor is to be selected from among one or more motion vector predictor candidates; generating a second flag indicating whether or not a motion vector predictor is to be selected from among the one or more motion vector predictor candidates in coding a current block to be coded in a predetermined coding mode, when the first flag indicates that a motion vector predictor is to be selected; and generating a coded signal in which the first flag and the second flag are included in header information, when the first flag indicates that a motion vector predictor is to be selected.

Abstract: A method for coding image information includes generating prediction information by predicting information on a current coding unit, and determining whether the information on the current coding unit is the same as the prediction information. When the information on the current coding unit is the same as the prediction information, a flag indicating that the information on the current coding unit is the same as the prediction information is coded and transmitted. When the information on the current coding unit is not the same as the prediction information, a flag indicating that the information on the current coding unit is not the same as the prediction information and the information on the current coding unit are coded and transmitted. At the generating of the prediction information, the prediction information is generated by using the information on the coding unit neighboring to the current coding unit.

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.