Abstract: A method for decoding an image, according to the present invention, can comprise the steps of: drawing out a vector predictor of a block vector for indicating a reference block with respect to a current block to be predicted within a current picture; drawing out the block vector on the basis of the vector predictor and a vector differential value corresponding to a different value of the block vector and the vector predictor; and generating a prediction block with respect to the current block on the basis of the block vector.

Abstract: A method of coding of video data is disclosed. According to the method, a predicted luma quantization parameter is derived and a luma quantization parameter is generated. The predicted luma quantization parameter is derived by using a tree type specifying whether a single tree or a dual tree is used to partition a coding tree. The luma quantization parameter is generated by using the predicted luma quantization parameter. The predicted luma quantization parameter is set equal to a luma quantization parameter of a coding unit containing a luma coding block covering a neighbouring location by using a current quantization group and a neighbouring block availability.

Abstract: A method comprises dividing a largest coding unit (LCU) of a picture into a plurality of motion estimation regions (MERs) having size equal to or less than a predetermined size. For one or more MERs of the plurality of MERs, a number of first motion searches are performed for determining a first quad-tree based on a cost function associated with a first plurality of prediction units (PUs) of the one or more MERs. A number of second motion searches are performed for the LCU, for determining a second quad-tree, based on the cost function associated with a second plurality of PUs of the LCU. The first quad-tree or the second quad-tree is selected for performing encoding of the picture based on a comparison of a first cost of the first quad-tree with a second cost of the second quad-tree.

Abstract: A method of decoding an encoded video. The method includes obtaining the encoded video bitstream and determining whether a chroma array type of a video sequence included in the encoded video bitstream is a first chroma array type indicating that the video sequence includes multiple color planes and that the multiple color planes are jointly. In addition, based on determining that the chroma array type is not the first chroma array type, the method further includes setting a value of at least one syntax element to zero without parsing the at least one syntax element from the encoded video bitstream, and based on the value of the at least one syntax element being zero, decoding the video sequence without applying at least one tool corresponding to the at least one syntax element.

Abstract: A device for encoding/decoding the image according to the present invention includes an intra prediction module configured to: determine an intra prediction mode of a current block; determine a scanning order of multiple sub blocks in the current block on the basis of the determined intra prediction mode; and perform intra prediction of the current block on the basis of the determined scanning order.

Abstract: In some aspects, the disclosure is directed to methods and systems for reducing memory utilization and increasing efficiency during affine merge mode for versatile video coding by utilizing motion vectors stored in a motion data line buffer for a prediction unit of a second coding tree unit neighboring a first coding tree unit to derive control point motion vectors for the first coding tree unit.

Abstract: A method and apparatus for encoding or decoding a video sequence includes applying a Cross-Component Linear Model (CCLM) to a video sequence, and applying an interpolation filter in the Cross-Component Linear Model (CCLM), wherein the interpolation filter is dependent upon a YUV format of the video sequence.

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: In transform coefficient coding, predetermined sets of transforms may be used. Embodiments of the present invention provide an encoder and a decoder for encoding a picture into/from a data stream using block-based prediction and block-based residual coding, the encoder and decoder supporting a set of transforms for the block-based residual coding. The encoder and decoder are configured to determine a transform candidate list of transforms for a current residual block out of the set of transforms based on a height and a width of the current residual block, and to encode/decode a prediction residual within the residual block using one selected transform out of the selectable list of transforms and selectively signal/derive the selected transform in/from the data stream.

Abstract: An image decoding method according to the present invention can comprise the steps of: deriving merge candidates from neighboring blocks adjacent to a current block; generating a merge candidate list including the merge candidates, wherein the arrangement order of the merge candidates in the merge candidate list is determined on the basis of initial priorities; re-arranging the merge candidates included in the merge candidate list; decoding information for specifying at least one of the merge candidates included in the merge candidate list; and deriving motion information of the current block from a merge candidate corresponding to the information.

Abstract: A method for determining a reference index for a reference picture list is disclosed. A reference picture list structure in one of a sequence parameter set and a slice header is decoded. A reference index for the reference picture list structure is derived according to a value of a reference picture list flag. A number of reference index active syntax in the slice header is decoded, if a number of entries in the reference picture list structure is greater than 1. The number of reference index active syntax is defined for i. A variable is derived by adding one to a value of the number of reference index active syntax. A value subtracted one from a value of the variable specifies a maximum reference index for the reference picture list.

Abstract: A method, computer program, and computer system is provided for coding video data. Video data having a coding tree unit size is received. The coding tree unit size associated with the video data is signaled by setting two or more flags. The video data is encoded/decoded based on the flags corresponding to the signaled coding tree unit size.

Abstract: An image decoding method is disclosed in the present specification. An image decoding method according to the present invention may include: determining a position of a co-located block of a current block within a co-located picture (co-located picture); determining a representative motion vector of the current block by using motion information at the position of the co-located block; and deriving motion information on a sub-block included in the current block by using the representative motion vector.

Abstract: Methods, apparatus, systems for video processing, including video encoding or video decoding are described. One example method includes performing a conversion between a video comprising a video picture that includes a video slice and a bitstream of the video. The bitstream conforms to a format rule specifying that, in case a slice type of the video slice is type P and temporal motion vector prediction is enabled, usage of reference picture resampling (RPR) for a reference picture in a collocated reference picture list is disabled. The reference picture is indicated by a reference index of a collocated picture of the video slice used for the temporal motion vector prediction.

Abstract: A method of decoding an encoded video bitstream using at least one processor, including obtaining a first flag indicating whether a constant picture size is used in a coded video sequence including a current picture; based on the first flag indicating that the constant picture size is used, decoding the current picture without performing reference picture resampling; based on the first flag indicating that the constant picture size is not used, obtaining a second flag indicating whether a conformance window size is signaled; based on the second flag indicating that the conformance window size is signaled: obtaining the conformance window size, determining a resampling ratio between the current picture and a reference picture based on the conformance window size, and performing the reference picture resampling on the current picture using the resampling ratio.

Abstract: The method for deriving a temporal motion vector predictor according to the present invention comprises the steps of: selecting a reference picture for a current block; deciding a predictor block corresponding to a predetermined storage unit block, as a reference prediction unit for the current block, in the reference picture; and deriving the temporal motion vector predictor from motion information of the decided reference prediction unit. The present invention enhances image compression efficiency.

Abstract: Sub-table for history-based affine mode is described. In an exemplary aspect, a method for video processing includes deriving, deriving, for a conversion between a current block of video and a bitstream representation of the current block, an affine model for the current block based on affine related information, wherein the affine related information is stored in at least one first affine history motion vector prediction (HMVP) buffer of M first affine HMVP buffers or at least one affine sub-buffer of M affine sub-buffers (HB0, HB1, . . . HBM-1) into which a second affine HMVP buffer is divided, wherein the first affine HMVP buffer or affine HMVP sub-buffer being used to store affine related information of blocks coded prior the current block, M being an integer larger than 1; and performing the conversion by using the derived affine model.

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: Disclosed is a video signal processing method and device for encoding or decoding a video signal. More specifically, disclosed are a video signal processing method and a video signal processing device for performing the method, the method comprising: obtaining reference line information indicating a reference line for intra prediction of a current block among a plurality of reference lines comprising neighboring samples of the current block; determining, on the basis of the reference line information, an intra prediction mode for the current block among a plurality of intra prediction modes constituting an intra prediction mode set; and decoding the current block on the basis of a plurality of reference samples on the reference line according to the reference line information and the determined intra prediction mode.

Abstract: A digital media encoder/decoder uses a flexible quantization technique that provides the ability to vary quantization along various dimensions of the encoded digital media data, including spatial, frequency sub bands and color channels. The codec utilizes a signaling scheme to signal various permutations of flexible quantization combinations efficiently for primary usage scenarios. When a choice of quantizer is available, the codec efficiently encodes the current quantizer by defining a subset of quantizers and indexes the current quantizer from the set.

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 encoding information about a motion information predictor, comprising: selecting one of a plurality of motion information predictor candidates; and encoding information for identifying the selected motion information predictor candidate using CABAC coding, wherein the CABAC coding comprises, for at least one bit of said information, using the same context variable used for another inter prediction mode when one or both of a Triangle Merge mode or a Merge with Motion Vector Difference (MMVD) Merge mode is used.

Abstract: Overlapped block disparity estimation and compensation is described. Compensating for images with overlapped block disparity compensation (OBDC) involves determining if OBDC is enabled in a video bit stream, and determining if OBDC is enabled for one or more macroblocks that neighbor a first macroblock within the video bit stream. The neighboring macroblocks may be transform coded. If OBDC is enabled in the video bit stream and for the one or more neighboring macroblocks, predictions may be made for a region of the first macroblock that has an edge adjacent with the neighboring macroblocks. OBDC can be causally applied. Disparity compensation parameters or modes may be shared amongst views or layers. A variety of predictions may be used with causally-applied OBDC.

Abstract: A method of decoding an image, includes obtaining at least one offset for a picture, deriving a variable for scaling for the picture based on the at least one offset, and performing inter prediction based on the variable for scaling for the picture. The at least one offset is defined with a direction of scaling.

Abstract: A digital media encoder/decoder uses a flexible quantization technique that provides the ability to vary quantization along various dimensions of the encoded digital media data, including spatial, frequency sub bands and color channels. The codec utilizes a signaling scheme to signal various permutations of flexible quantization combinations efficiently for primary usage scenarios. When a choice of quantizer is available, the codec efficiently encodes the current quantizer by defining a subset of quantizers and indexes the current quantizer from the set.

Abstract: Disclosed are a method for predicting a current block using a current picture referencing mode (also called intra block copy (ibc) mode), and a video encoding or decoding device therefor. The method comprises: decoding, from a bitstream, an enable flag indicating whether the application of the ibc mode is allowed, and type information indicating whether the type of slices is an inter type; depending on the enable flag and the type information, decoding from the bitstream an ibc flag indicating whether a prediction mode for the current block is the ibc mode; when the ibc flag indicates the ibc mode, decoding motion information from the bitstream; and predicting the current block by using a block indicated by the motion information within a current picture in which the current block is located.

Abstract: Disclosed are a method for predicting a current block using a current picture referencing mode (also called intra block copy (ibc) mode), and a video encoding or decoding device therefor. The method comprises: decoding, from a bitstream, an enable flag indicating whether the application of the ibc mode is allowed, and type information indicating whether the type of slices is an inter type; depending on the enable flag and the type information, decoding from the bitstream an ibc flag indicating whether a prediction mode for the current block is the ibc mode; when the ibc flag indicates the ibc mode, decoding motion information from the bitstream; and predicting the current block by using a block indicated by the motion information within a current picture in which the current block is located.

Abstract: Disclosed are a method for predicting a current block using a current picture referencing mode (also called intra block copy (ibc) mode), and a video encoding or decoding device therefor. The method comprises: decoding, from a bitstream, an enable flag indicating whether the application of the ibc mode is allowed, and type information indicating whether the type of slices is an inter type; depending on the enable flag and the type information, decoding from the bitstream an ibc flag indicating whether a prediction mode for the current block is the ibc mode; when the ibc flag indicates the ibc mode, decoding motion information from the bitstream; and predicting the current block by using a block indicated by the motion information within a current picture in which the current block is located.

Abstract: Disclosed are a method for predicting a current block using a current picture referencing mode (also called intra block copy (ibc) mode), and a video encoding or decoding device therefor. The method comprises: decoding, from a bitstream, an enable flag indicating whether the application of the ibc mode is allowed, and type information indicating whether the type of slices is an inter type; depending on the enable flag and the type information, decoding from the bitstream an ibc flag indicating whether a prediction mode for the current block is the ibc mode; when the ibc flag indicates the ibc mode, decoding motion information from the bitstream; and predicting the current block by using a block indicated by the motion information within a current picture in which the current block is located.

Abstract: A decoder for decoding a data stream into which media data is coded has a mode switch configured to activate a low-complexity mode or a high-efficiency mode depending on the data stream, an entropy decoding engine configured to retrieve each symbol of a sequence of symbols by entropy decoding using a selected one of a plurality of entropy decoding schemes, a desymbolizer configured to desymbolize the sequence of symbols to obtain a sequence of syntax elements, a reconstructor configured to reconstruct the media data based on the sequence of syntax elements, selection depending on the activated low-complexity mode or the high-efficiency mode.

Abstract: Devices, systems and methods for the simplification of sub-block motion candidate lists for video coding are described. In a representative aspect, a method for video processing includes determining, during a conversion between a current block of a video and a bitstream representation of the video, a temporal motion vector prediction candidate based on a temporal neighboring block of the current block. The temporal neighboring block is identified based on motion information of a spatial neighboring block selected from one or more spatial neighboring blocks that are different from at least one spatial neighboring block used in a merge list construction process of a video block. The method also includes performing the conversion based on the temporal motion vector prediction candidate.

Abstract: The present invention relates to the encoding and decoding of image information. According to the present invention, the decoding method comprises the steps of: entropy-decoding received information; performing inter prediction on a current block based on the entropy-decoded information; and restoring images by using the prediction results, wherein, in the inter prediction step, a skip mode or merge mode is applied to the current block and movement information of the current block may be determined based on the movement information of a neighboring block of the current block.

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: An image decoding method performed by a decoding apparatus, according to the present document, comprises the steps of: deriving a multilayer output layer set (OLS) index of a target OLS in a list of multilayer OLSs; acquiring hypothetical reference decoder (HRD)-related information and decoded picture buffer (DPB)-related information for the target OLS, on the basis of the multilayer OLS index; and decoding a picture within the target OLS, on the basis of the HRD-related information and the DPB-related information, wherein the multilayer OLSs are OLSs including a plurality of layers, and the target OLS is one of the multilayer OLSs.

Abstract: An encoding method is provided for encoding a picture to generate a coded stream. The encoding method incldues: generating a first prediction image of a current block included in a current picture by referring to a first region included in a reference picture different from the current picture; operating a bi-directional optical flow process to generate a second prediction image based on the first prediction image by referring to a second region included in the first region, and not operating the bi-directional optical flow process by referring to a third region not included in the first region; and encoding the current block based on the second prediction image.

Abstract: The present disclosure is directed to systems and methods for estimating machine rotation state. The rotation state can include the rotation speed and/or angle as the machine rotates. In some implementations, an estimating machine rotation state system can receive image data, timestamped consecutively, from camera devices of a machine. The estimating machine rotation state system can generate optical flow vectors for the pixels of the image data and determine the hue and intensity of the pixels based on the optical flow vectors. Using the hues, intensities, and timestamps of the image data, the estimating machine rotation state system can generate an intensity plot over time. The estimating rotation states system can then determine a rotation speed of the machine based on the intensity plot. The estimating rotation states system can also determine a rotation angle of the machine by integrating the intensity plot over time.

Abstract: The image encoding/decoding method and device according to the present invention can construct a merge candidate list of a current block, derive motion information of the current block on the basis of the merge candidate list and a merge index of the current block, derive a motion vector difference of the current block, correct a motion vector of the current block by means of the motion vector difference, and carry out motion compensation on the current block by means of the corrected motion vector.

Abstract: Provided are an image encoding method and device. When carrying out image encoding for a block within a slice, at least one block in a restored block of the slice is set as a reference block. When this is done, the encoding parameters of the reference block are distinguished, and the block to be encoded is encoded adaptively based on the encoding parameters.

Abstract: Disclosed herein are a method, an apparatus and a storage medium for performing encoding/decoding on an image using a subpicture. A picture may be partitioned into various units such as subpictures and slices, and various syntax elements and structures may be used to specify the units. In an embodiment, there is a method for configuring a reference picture list for motion compensation in the case where the location of a reference subpicture to be referred to for motion compensation is different from the location of a target subpicture. Further, in an embodiment, there is provided a method for providing the configuration of a reference picture list and an override on the number of activated reference indexes.

Abstract: Provided are an image encoding method and device. When carrying out image encoding for a block within a slice, at least one block in a restored block of the slice is set as a reference block. When this is done, the encoding parameters of the reference block are distinguished, and the block to be encoded is encoded adaptively based on the encoding parameters.

Abstract: The present disclosure provides method and apparatus for motion field storage in video coding. An exemplary method includes: determining whether a first uni-prediction motion vector for a first partition of a block and a second uni-prediction motion vector for a second partition of the block are from a same reference picture list; and in response to the first uni-prediction motion vector and the second uni-prediction motion vector being determined to be from the same reference picture list, storing, in a motion field of the block, one of the first uni-prediction motion vector and the second uni-prediction motion vector for a subblock located in a bi-predicted area of the block.

Abstract: A system includes memory and at least one processor coupled to the memory. The processor processes a received bitstream to generate quantized data and control data. The process also generate decoded motion data based on a portion of the control data, fetches one or more reference blocks associated with a current prediction unit (PU) of a DPR based on the decoded motion data and generates refined motion data based on the decoded motion data and the one or more reference blocks. The processor further generates one or more inter-prediction blocks based on the refined motion data and the one or more reference blocks by performing a motion compensation operation.

Abstract: An encoding device that includes a deriving unit and an encoding unit. The deriving unit is configured to derive a first reference value based on fixed point precision representing roughness of a weighting factor that is used for multiplying a reference image. The encoding unit is configured to encode a first difference value that is a difference value between the weighting factor and the first reference value and the fixed point precision. The weighting factor is included in a first range of predetermined bit precision having the first reference value at approximate center. The first difference value is in the predetermined range.

Abstract: Decoding a current block of a current frame includes obtaining motion trajectories between the current frame and at least one previously coded frame by projecting motion vectors from the at least one previously coded frame onto the current frame. A motion field is obtained between the current frame and a reference frame used for coding the current frame. The motion field is obtained by extending the motion trajectories from the current frame towards the reference frame. A motion vector for the current block is identified based on the motion field. A prediction block is obtained for the current block using a reference block of the reference frame identified using the motion vector.

Abstract: In a method to improve the coding efficiency of high-dynamic range (HDR) images, a decoder parses sequence processing set (SPS) data from an input coded bitstream to detect that an HDR extension syntax structure is present in the parsed SPS data. It extracts from the HDR extension syntax structure post-processing information that includes one or more of a color space enabled flag, a color enhancement enabled flag, an adaptive reshaping enabled flag, a dynamic range conversion flag, a color correction enabled flag, or an SDR viewable flag. It decodes the input bitstream to generate a preliminary output decoded signal, and generates a second output signal based on the preliminary output signal and the post-processing information.

Abstract: A method of video decoding includes creating a candidate list for a current block in current picture included in a coded video bitstream. The method further includes determining a coding mode for at candidate block associated with the current block. The method further it determining whether to add, to the candidate list, a vector associated the candidate block based on the determined coding mode. The method further includes reconstructing the current block using at least one candidate from the candidate list.

Abstract: A method by which a decoding device performs image decoding, according to the present document, comprises the steps of: deriving a reference block on the basis of a motion shift; determining whether a subblock temporal motion vector predictor (sbTMVP) candidate is available, on the basis of whether the reference block is a current picture referencing (CPR) block; deriving motion information about a current block on the basis of the sbTMVP candidate when the sbTMVP candidate is available; generating prediction samples on the basis of the motion information; and generating a restored picture on the basis of the prediction samples, wherein the sbTMVP candidate is determined to be unavailable with respect to the reference block which is the CPR block.

Abstract: Disclosed herein are an image encoding method and an image decoding method. The image decoding method of the present disclosure may include reconstructing reference pixel line information, selecting, based on the reference pixel line information, at least one reference pixel line among a plurality of reference pixel lines, and generating a prediction block for a current block by performing intra prediction for the current block based on the selected reference pixel line.

Abstract: Devices, systems and methods for unified rounding in sub-block based prediction are described. In a representative aspect, a method of video processing includes generating, for a processing of a current block of video, a pairwise merge candidate based on a pair of motion candidates, and performing, based on the pairwise merge candidate, a conversion between the current block and a bitstream representation of the video. In another representative aspect, a method of video processing includes generating, for a current block of video coded using a geometry partition mode, a uni-prediction motion candidate based on a scaled motion vector and a List0 motion vector, and performing, based on the uni-prediction motion candidate, a conversion between the current block and a bitstream representation of the video.

Abstract: A method of decoding an image, includes obtaining at least one offset for a picture, deriving a variable for scaling for the picture based on the at least one offset, and performing inter prediction based on the variable for scaling for the picture. The at least one offset is defined with a direction of scaling.