Abstract: The present disclosure provides methods, apparatus and non-transitory computer readable medium for processing video data. According to certain disclosed embodiments, a method includes: determining a set of parameters from a plurality of sets of parameters wherein the set of parameters includes a scaling factor; determining a predicted sample value of a first chroma component based on the set of the parameters, a reconstructed sample value of a luma component and a reconstructed sample value of a second chroma component; and signaling an index associated with the set of parameters in a bitstream.

Abstract: Systems and methods are described for reducing the complexity of using bi-directional optical flow (BIO) in video coding. In some embodiments, bit-width reduction steps are introduced in the BIO motion refinement process to reduce the maximum bit-width used for BIO calculations. In some embodiments, simplified interpolation filters are used to generate predicted samples in an extended region around a current coding unit. In some embodiments, different interpolation filters are used for vertical versus horizontal interpolation. In some embodiments, BIO is disabled for coding units with small heights and/or for coding units that are predicted using a sub-block level inter prediction technique, such as advanced temporal motion vector prediction (ATMVP) or affine prediction.

Abstract: Methods and apparatus for using flexible grid regions in picture or video frames are disclosed. In one embodiment, a method includes receiving a set of first parameters that defines a plurality of first grid regions comprising a frame. For each first grid region, the method includes receiving a set of second parameters that defines a plurality of second grid regions, and the plurality of second grid regions partitions the respective first grid region. The method further includes partitioning the frame into the plurality of first grid regions based on the set of first parameters, and partitioning each first grid region into the plurality of second grid regions based on the respective set of second parameters.

Abstract: Power aware adaptation for a power aware video streaming system may be based on the complexity information conveyed in different ways. A complexity level of a data stream, such as a video data stream, may be selected as a function of a remaining battery power of a wireless transmit/receive unit (WTRU) and on a state set of a plurality of state sets that may be stored and/or managed by the WTRU. These state sets may correspond to, for example, different content sources and/or different complexity estimation algorithms and may be used to select the complexity level of the data stream. The data stream may then be received at the selected complexity level. The complexity level and/or a bitrate of the data stream may be adapted to accommodate, for example, the remaining battery power and/or other circumstances. The adaptation may be customized according to the objectives of use cases.

Abstract: Exemplary embodiments include systems and methods for coding a video comprising a plurality of pictures including a current picture, a first reference picture, and a second reference picture, where each picture includes a plurality of blocks. In one method, for at least a current block in the current picture, a number of available bi-prediction weights is determined based at least in part on a temporal layer and/or a quantization parameter of the current picture. From among available bi-prediction weights a pair of weights are identified. Using the identified weights, the current block is then predicted as a weighted sum of a first reference block in the first reference picture and a second reference block in the second reference picture. Encoding techniques are also described for efficient searching and selection of a pair of bi-prediction weights to use for prediction of a block.

Abstract: The present disclosure provides video decoding method. An exemplary method includes: decoding a first parameter for a coding unit from a bitstream, and determining a candidate for the coding unit based on the first parameter; determining a value of a second parameter associated with the coding unit based on a value of a second parameter associated with the candidate, wherein the second parameter indicates whether a bi-directional prediction correction is enabled; and in response to the value of the second parameter associated with the coding unit indicating the bi-directional prediction correction being enabled, performing the bi-directional prediction correction on the coding unit.

Abstract: 360-degree video content may be coded. A sampling position in a projection format may be determined to code 360-degree video content. For example, a sampling position in a target projection format and a sampling position in a reference projection format may be identified. The sample position in the target projection format may be related to the corresponding sample position in the reference projection format via a transform function. A parameter weight (e.g., a reference parameter weight) for the sampling position in the reference projection format may be identified. An adjustment factor associated with the parameter weight for the sampling position in the reference projection format may be determined. The parameter weight (e.g., adjusted parameter weight) for the sampling position in the target projection format may be calculated. The calculated adjusted parameter weight may be applied to the sampling position in the target projection format when coding the 360-degree video content.

Abstract: Systems, methods, and instrumentalities are disclosed for performing horizontal geometry padding on a current sample based on receiving a wraparound enabled indication that indicates whether a horizontal wraparound motion compensation is enabled. If the horizontal wraparound motion compensation is enabled based on the wraparound enabled indication, a video coding device may determine a reference sample wraparound offset of a current sample in a picture. The reference sample wraparound offset may indicate a face width of the picture. The video coding device may determine a reference sample location for the current sample based on the reference sample wraparound offset, a picture width of the picture, and a current sample location. The video coding device may predict the current sample based on the reference sample location in a horizontal direction. Repetitive padding or clipping may be used in the vertical direction.

Abstract: Systems, methods, and instrumentalities may be provided for determining whether to bypass bi-directional optical flow (BDOF) if BDOF is used in combination with bi-prediction with coding unit (CU) weights (e.g., generalized bi-prediction (GBi)). A coding system may combine coding modes, coding techniques, and/or coding tools. The coding system may include a wireless transmit/receive unit (WTRU). For example, the coding system may combine BDOF and bi-prediction with GU weights (BCW). BDOF may include refining a motion vector associated with a current CU based at least in part on gradients associated with a location in the current CU. The coding system may determine that BDOF is enabled, and/or that bi-prediction with CU weights is enabled for the current CU. The coding system's determination that bi-prediction with CU weights is enabled and/or that BDOF is enabled may be based on one or more indications.

Abstract: The present disclosure provides methods and systems for motion compensation. The method can include: determining a plurality of intermediate interpolation coefficients of an interpolation filter, the determining of the plurality of intermediate interpolation coefficients being: based on positions of a plurality of integer samples respectively, and based on fractional reference positions of a plurality of fractional samples respectively; determining a plurality of integer interpolation coefficients of the interpolation filter by rounding the plurality of intermediate interpolation coefficients to a plurality of integers respectively; and applying the plurality of integer interpolation coefficients on a picture to perform motion compensation prediction.

Abstract: Conversion between different projection formats of a 360-degree video may be performed in a uniform way. The geometric characteristics of the different projection formats may be considered when applying 3D-to-2D and 2D-to-3D mapping. Parameters reflective of the geometric characteristics of the different projection formats may be determined and used in the mapping and/or conversion. The parameters may include a normal vector that is perpendicular to a projection plane, a reference point in the projection plane, and/or unit vectors defined in the projection plane. An architecture with consolidated modules for handling the various projection formats may be provided.

Abstract: The present disclosure provides systems and methods for inter prediction process in video data coding. One exemplary method comprises: selecting one of a DMVR process and a BDOF process, based on a video bitstream; and inter predicting an image block based on the selected process. The selection can be made either through explicit signaling, or implicit derivation at the decoder side. According to one exemplary method, selecting the one of the DMVR process and the BDOF process can be performed by selecting the one of the DMVR process and the BDOF process based on: a flag signaled at at least one of a coding unit (CU) level and a coding tree unit (CTU) level, or a merge candidate index associated with an extended merge candidate list.

Abstract: The present disclosure provides a computer-implemented method for decoding video. The method includes: receiving a bitstream comprising a first flag indicating whether an angular weighted prediction (AWP) mode is used for a coded unit; and in response to a determination that the AWP mode is used for the coded unit, decoding the bitstream in the AWP mode for an inter prediction.

Abstract: The present disclosure provides methods, apparatus and non-transitory computer readable medium for processing video data. According to certain disclosed embodiments, a method includes: receiving one or more video sequences for processing; and coding the one or more video sequences using only one of a low-frequency non-separable transform (LFNST) and an adaptive color transform (ACT).

Abstract: Techniques for selecting a coding mode for an image coding process are described. Coding modes can be selected through a coding mode transition state machine, a re-quantization process, selection of an optimal transform size, by skipping some quantization parameters, or by performing motion search.

Abstract: The present disclosure provides systems and methods for performing adaptive resolution change during video encoding and decoding. The methods include: comparing resolutions of a target picture and a first reference picture; in response to the target picture and the first reference picture having different resolutions, resampling the first reference picture to generate a second reference picture; and encoding or decoding the target picture using the second reference picture.

Abstract: The present disclosure provides systems and methods for processing video content. The method can include: receiving a bitstream comprising video content; determining whether a first signal associated with the video content satisfies a given condition; and in response to the determination that the first signal satisfies the given condition, disabling both a cross component adaptive loop filter (CCALF) process and a chroma adaptive loop filter (ALF) process.

Abstract: The present disclosure provides systems and methods for video decoding. The method can include: receiving a video bitstream; determining whether a first flag associated with the bitstream satisfies a given condition; and in response to the determination that the first flag satisfies the given condition, disabling the process for the bitstream, wherein the decoding process comprises at least one of position dependent intra prediction combination (PDPC) and intra reference filtering.

Abstract: The present disclosure provides a computer-implemented method for video processing. The method includes deriving a total number by summing a number of reference picture list structures in sequence parameter set (SPS) and one; allocating memory for the total number of reference picture list structures in response to a reference picture list structure being signaled in a picture header of a current picture or a slice header of a current slice; and processing a current picture or a current slice using the allocated memory.

Abstract: The present disclosure provides a computer-implemented method for encoding or decoding video. The method includes encoding or decoding, in a plurality of picture parameter sets (PPS) associated with pictures of a coded layer video sequence (CLVS), corresponding first PPS flags indicating whether pictures are allowed to be partitioned into a plurality of tiles or slices. In a first PPS, a corresponding first PPS flag with a first value indicates a first picture of the CLVS is unpartitioned, and in a second PPS, another corresponding first PPS flag with a second value being different from the first value indicates that a second picture of the CLVS is allowed to be partitioned.