Abstract: The present disclosure relates to methods and devices to be employed for encoding and decoding of image or video signal. They include determination of whether or not the size of a current block is larger than a minimum allowed quadtree leaf node size. If the size of the current block is not larger than the minimum allowed quadtree leaf node size, multi-type tree splitting is applied to the current block. The minimum allowed quadtree leaf node size is not larger than a maximum allowed binary tree root node size or the minimum allowed quadtree leaf node size is not larger than a maximum allowed ternary tree root node size.

Abstract: A prediction method for an image block comprising a first prediction sub-block and a second prediction sub-block, the prediction method comprising: parsing a first index from a bitstream, wherein the first index is used to obtain prediction information of the first prediction sub-block; parsing a second index from the bitstream; comparing the first index with the second index; adjusting the second index in the event that the second index is equal to or greater than the first index; and obtaining prediction information of the second prediction sub-block according to the adjusted second index.

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: The present disclosure provides methods and devices of construct a candidate merge list for Intra block copy (IBC) mode, the method comprising: inserting a block vector of a left neighboring block of a current block into an initial merge list, when the left neighboring block is available and the left neighboring block is using IBC mode; inserting a block vector of an above neighboring block of the current block into the initial merge list, when the above neighboring block is available, the above neighboring block is using IBC mode and the block vector of the above neighboring block is not same as the block vector of the left neighboring block; inserting a block vector of the last candidate in a history based motion vector predictor (HMVP) into the initial merge list; obtaining a block vector of the current block according to the initial merge list.

Abstract: A method of coding implemented is provided. The method includes the following operations: obtained the height and width of a prediction block without applying clipping operation; calculating a value of a vertical component of an intra prediction sample based on the height and width of the prediction block; calculating a value of a horizontal component of the intra prediction sample based on the height and width of the prediction block; and generating the intra prediction sample based on the value of the vertical component and the value of the horizon component.

Abstract: A system and method of decoding of a video or picture bitstream implemented by a decoding device are described. The bitstream can include data representing a current video coding layer. Furthermore, when determining that the current video coding layer is the only one layer in the bitstream, the method can include using the identifier of a NAL unit of the current video coding layer as the identifier of the current video coding layer.

Abstract: A method and apparatus are provided for processing with a trained neural network, and for training of such neural network for image modification, which relate to image processing and in particular to modification of an image using the processing such as the neural network. The processing is performed to generate an output image. The output image is generated by processing the input image with the neural network. The processing with the neural network includes at least one stage including image down-sampling and filtering of the down-sampled image and at least one stage of image up-sampling. The image down-sampling is performed by applying a strided convolution. According to the application, efficiency of the neural network is increased, which may lead to faster learning and improved performance.

Abstract: The present disclosure relates to image processing and in particular to modification of an image using a processing such as neural network. The processing is performed to generate a correction image based on an input image. Then, the input image is modified by combining it with the correction image. The processing with the neural network includes at least one stage including image down-sampling and filtering of the down-sampled image; and at least one stage of image up-sampling. An advantage of such approach is increased efficiency of the neural network, which may lead to faster learning and improved performance. The embodiments provide methods and apparatuses for the processing with a trained neural network, as well as methods and apparatuses for training of such neural network for image modification.

Abstract: A method of decoding of a video or picture bitstream implemented by a decoding device, the bitstream including a current sequence parameter set (SPS) comprising syntax elements that apply to a video sequence, the method comprising: obtaining a first syntax element used to determine a maximum number of temporal sublayers that is allowed to be present in each coded layer video sequence) referring to the current SPS, wherein a value of the first syntax element is in a range of 0 to a first value, wherein the first value is a value of a second syntax element used to determine the maximum number of temporal sublayers that is allowed to present in a layer in each coded video sequence referring to a video parameter set, when the second syntax element is referred to by the SPS; decoding the bitstream based on the value of the first syntax element.

Abstract: The present disclosure provides methods and devices. A video method of coding implemented by a decoding device, comprising: when a prediction mode of a current coding block is intra prediction, and the current coding block is processed by using Intra sub-partition coding mode, determining whether a width of a current transform block is larger than or equal to a first threshold or not, and whether the width of the current transform block is smaller than or equal to a second threshold or not, the current transform block corresponding to the current coding block; when the width of the current transform block is larger than or equal to the first threshold and the width of the current transform block is smaller than or equal to the second threshold, performing transform process on the current transform block, wherein a transform core based on DST 7 is used on horizontal direction transform.

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

Abstract: A method to derive candidate intra prediction modes, comprising: recording an intra prediction mode of at least one previous coding unit, wherein the previous coding unit is not adjacent to a to-be-processed coding unit; adding at least one recorded intra prediction mode into a set of candidate intra prediction modes, when the number of the candidate intra prediction modes is less than a preset threshold.

Abstract: Devices and methods for Intra prediction are provided. The method includes: obtaining a value of an indication information of a current block. When the value of the indication information indicates the intra prediction mode of the current block is not comprised in the set of most probable modes, deriving the intra prediction mode IntraPredModeY of the current block by the following ordered steps: i. IntraPredModeY is set equal to intra_luma_mpm_remainder[xCb][yCb], ii. The value of IntraPredModeY is incremented by one. The method can improve the efficiency to determine the intra prediction mode of the current block.

Abstract: The disclosure relates to a method of decoding implemented by a decoding device, comprising: obtaining a value of a reference line index for a current block; constructing a most probable mode, MPM, list for the current block; obtaining a value of intra-prediction mode index for the current block; when the value of the reference line index is not equal to 0, obtaining an intra prediction mode of the current block according to the MPM list for the current block and the value of the intra-prediction mode index for the current block, wherein the value of the intra-prediction mode index indicates a position that corresponds to the intra prediction mode of the current block among angular intra-prediction modes in the MPM list. The disclosure also relates to a coding apparatus and a non-transitory machine-readable medium.

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: A prediction method for an image block comprising a first prediction sub-block and a second prediction sub-block, the prediction method comprising: parsing a first index from a bitstream, wherein the first index is used to obtain prediction information of the first prediction sub-block; parsing a second index from the bitstream; comparing the first index with the second index; adjusting the second index in the event that the second index is equal to or greater than the first index; and obtaining prediction information of the second prediction sub-block according to the adjusted second index.

Abstract: Embodiments provide methods and devices (encoder and/or decoder) of coding a picture. A History Based Motion Vector Prediction (HMVP) list for a current Coding Tree Unit (CTU) row within a tile of a picture is initialized and a CTU of the current CTU row is processed based on the initialized HMVP list.

Abstract: A method of coding implemented by a decoding device, comprising initializing a dedicated buffer for intra block copy (IBC) referencing, when a current coding tree unit (CTU) to be decoded is a first CTU of a CTU row, determining whether a current block in the current CTU is predicted using IBC mode, obtaining an IBC block vector for the current block when the current block is predicted using IBC mode, and obtaining predicted sample values for the current block, based on reference samples from the dedicated buffer and the IBC block vector for the current block.

Abstract: A method of coding implemented by a decoding device and a decoder are disclosed, the method comprising: obtaining a bitstream for a current picture; obtaining a quantity of tiles in a tile row of the current picture; obtaining a value of an address of a current slice, the current slice is comprised in the current picture; obtaining a value of tileX according to the value of the address of the current slice; parsing an indication value for a slice width from the bitstream for the current picture, when a difference value between the quantity of tiles in the tile row of the current picture and the value of tileX is not equal to a first threshold.

Abstract: The present disclosure provides methods and devices of construct a candidate merge list for Intra block copy (IBC) mode, the method comprising: inserting a block vector of a left neighboring block of a current block into an initial merge list, when the left neighboring block is available and the left neighboring block is using IBC mode; inserting a block vector of an above neighboring block of the current block into the initial merge list, when the above neighboring block is available, the above neighboring block is using IBC mode and the block vector of the above neighboring block is not same as the block vector of the left neighboring block; inserting a block vector of the last candidate in a history based motion vector predictor (HMVP) into the initial merge list; obtaining a block vector of the current block according to the initial merge list.