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: A method for receiving and displaying media content may be provided. The method may include requesting a set of DASH video segments that are associated with various viewports and qualities. The method may include displaying the DASH video segments. The method may include determining a latency metric based on a time difference between the display of a DASH video segment and one of: a device beginning to move, the device ceasing to move, the device determining that the device has begun to move, the device determining that the device has stopped moving, or the display of a different DASH video segment. The different DASH video segment may be associated with one or more of a different quality or a different viewport.

Abstract: Systems, methods, and instrumentalities are described herein for calculating local illumination compensation (LIC) parameters for bi-predicted coding unit (CU). The LIC parameters may be used to generate adjusted samples for the current CU and to address local illumination changes that may exist among temporal neighboring pictures. LIC parameters may be calculated based on bi-predicted reference template samples and template samples for a current CU. Bi-predicted reference template samples may be generated based on reference template samples neighboring temporal reference CUs. For example, the bi-predicted reference template samples may be generated based on averaging the reference template samples. The reference template samples may correspond to template samples for the current CU. A CU may be or may include a coding block and/or a sub-block that may be derived by dividing the coding block.

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: Systems, methods, and instrumentalities are disclosed for processing history-based motion vector prediction (HMVP). A video coding device may generate a history-based motion vector prediction (HMVP) list for a current block. The video coding device derive an HMVP candidate from a previously coded block. The HMVP candidate may include motion information associated with a neighboring block of the current block, one or more reference indices, and a bi-prediction weight index. The video coding device may add the HMVP candidate to the HMVP list for motion compensated prediction of a motion vector associated with the current block. The video coding device use one HMVP selected from the HMVP list to perform motion compensated prediction of the current block. The motion compensated prediction may be performed using the motion information associated with the neighboring block of the current block, the one or more reference indices, and the bi-prediction weight index.

Abstract: A media content processing device may decode visual volumetric content based on one or more messages, which may indicate which attribute sub-bitstream of one or more attribute sub-bitstreams indicated in a parameter set is active, The parameter set may include a visual volumetric video-based parameter set. The message indicating one or more active attribute sub-bitstreams may be received by the decoder, A decoder may perform decoding, such as determining which attribute sub-bitstream to use for decoding visual media content, based on the one or more messages, The one or more messages may be generated and sent to a decoder, for example, to indicate the deactivation of the one or more attribute sub-bitstreams. The decoder may determine an inactive attribute sub-bitstream and skip the inactive attribute sub-bitstream for decoding the visual media content based on the one or more messages.

Abstract: Procedures, methods, architectures, apparatuses, systems, devices, and computer program products directed to improved linear model estimation for template-based video coding are provided. Included therein is a method comprising determining minimum and maximum (“min/max”) values of luma and chroma samples neighboring a coding block, wherein the min/max chroma values correspond to the min/max luma values; determining a first linear model parameter of a template-based video coding technique (i) based on a single look-up table and the min/max chroma values and (ii) at a precision no greater than 16 bits; determining a second linear model parameter of the template-based video coding technique (i) based on the first linear model parameter and the minimum chroma and luma values and (ii) at a precision no greater than 16 bits; and predicting chroma samples of the coding block based on reconstructed luma samples of the coding block and the first and second linear model parameters.

Abstract: Video data may be palette decoded. Data defining a palette table may be received. The palette table may comprise index values corresponding to respective colors. Palette index prediction data may be received and may comprise data indicating index values for at least a portion of a palette index map mapping pixels of the video data to color indices in the palette table. The palette index prediction data may comprise run value data associating run values with index values for at least a portion of a palette index map. A run value may be associated with an escape color index. The palette index map may be generated from the palette index prediction data at least in part by determining whether to adjust an index value of the palette index prediction data based on a last index value. The video data may be reconstructed in accordance with the palette index map.

Abstract: Coding techniques for 360-degree video are described. An encoder selects a projection format and maps the 360-degree video to a 2D planar video using the selected projection format. The encoder encodes the 2D planar video in a bitstream and further signals, in the bitstream, parameters identifying the projection format. The parameters identifying the projection format may be signaled in a video parameter set, sequence parameter set, and/or picture parameter set of the bitstream. Different projection formats that may be signaled include formats using geometries such as equirectangular, cubemap, equal-area, octahedron, icosahedron, cylinder, and user-specified polygon. Other parameters that may be signaled include different arrangements of geometric faces or different encoding quality for different faces. Corresponding decoders are also described. In some embodiments, projection parameters may further include relative geometry rotation parameters that define an orientation of the projection geometry.

Abstract: Systems, methods, and instrumentalities are disclosed relating to intra prediction of a video signal based on mode-dependent subsampling. A block of coefficients associated with a first sub block of a video block, one or more blocks of coefficients associated with one or more remaining sub blocks of the video block, and an indication of a prediction mode for the video block may be received. One or more interpolating techniques, a predicted first sub block, and the predicted sub blocks of the one or more remaining sub blocks may be determined. A reconstructed first sub block and one or more reconstructed remaining sub blocks may be generated. A reconstructed video block may be formed based on the prediction mode, the reconstructed first sub block, and the one or more reconstructed remaining sub blocks.

Abstract: Systems and methods are described for video coding using affine motion prediction. In an example method, motion vector gradients are determined from respective motion vectors of a plurality of neighboring sub-blocks neighboring a current block. An estimate of at least one affine parameter for the current block is determined based on the motion vector gradients. An affine motion model is determined based at least in part on the estimated affine parameter(s), and a prediction of the current block is generated using the affine motion model. The estimated parameter(s) may be used in the affine motion model itself. Alternatively, the estimated parameter(s) may be used in a prediction of the affine motion model. In some embodiments, only neighboring sub-blocks above and/or to the left of the current block are used in estimating the affine parameter(s).

Abstract: Systems, methods, and instrumentalities are disclosed for a 360-degree video streaming. A video streaming device may receive a 360-degree video stream from a network node. The video streaming device may determine a viewport associated with the video streaming device and/or the 360-degree video stream. The video streaming device may determine (e.g., based on the viewport) to request in advance a first segment and a second segment of the 360-degree video stream. The video streaming device may determine a relative priority order for the first segment and the second segment. The video streaming device may generate an anticipated requests message. The anticipated requests message may indicate the determined relative priority order, for example, by listing the first segment and the second segment in decreasing relative priority based on the determined relative priority order. The video streaming device may send the anticipated requests message to the network node.

Abstract: Processing a 360-degree video content for video coding may include receiving the video content in a first geometry. The video content may include unaligned chroma and luma components associated with a first chroma sampling scheme. The unaligned chroma and luma components may be aligned to a sampling grid associated with a second chroma sampling scheme that has aligned chroma and luma components. A geometric conversion to the video content may be performed. The video content, that may comprise the aligned chroma and luma components, in the first geometry may be converted to a second geometry. The first geometry may be a stitched geometry, and the second geometry may be a coding geometry. The converted video content in the second geometry may include the chroma and luma components aligned to the sampling grid associated with the second chroma sampling scheme.

Abstract: Described herein are methods and systems associated with viewing condition adaption of multimedia content. A method for receiving multimedia content with a device from a network may include determining a viewing parameter, transmitting a request for the multimedia content to the network, whereby the request may be based on the viewing parameter, and receiving the multimedia content from the network, whereby the multimedia content may be processed at a rate according to the viewing parameter. The viewing parameter may include at least one of: a user viewing parameter, a device viewing parameter, or a content viewing parameter. The method may further include receiving a multimedia presentation description (MPD) file from the network. The MPD file may include information relating to the rate of the multimedia content and information relating to the rate may include a descriptor relating to the viewing parameter, whereby the descriptor may be required or optional.

Abstract: A method for receiving and displaying media content may be provided. The method may include requesting a set of DASH video segments that are associated with various viewports and qualities. The method may include displaying the DASH video segments. The method may include determining a latency metric based on a time difference between the display of a DASH video segment and one of: a device beginning to move, the device ceasing to move, the device determining that the device has begun to move, the device determining that the device has stopped moving, or the display of a different DASH video segment. The different DASH video segment may be associated with one or more of a different quality or a different viewport.

Abstract: Systems, methods and instrumentalities are disclosed for adaptively selecting an adaptive loop filter (ALF) procedure for a frame based on which temporal layer the frame is in. ALF procedures may vary in computational complexity. One or more frames including the current frame may be in a temporal layer of a coding scheme. The decoder may determine the current frame's temporal layer level within the coding scheme. The decoder may select an ALF procedure based on the current frame's temporal layer level. If the current frame's temporal layer level is higher within the coding scheme than some other temporal layer levels, an ALF procedure that is less computationally complex may be selected for the current frame. Then the decoder may perform the selected ALF procedure on the current frame.

Abstract: A video coding system (e.g., an encoder and/or a decoder) may perform face-based sub-block motion compensation for 360-degree video to predict samples (e.g., of a sub-block). The video coding system may receive a 360-degree video content. The 360-degree video content may include a current block. The current block may include a plurality of sub-blocks. The system may determine whether a sub-block mode is used for the current block. The system may predict a sample in the current block based on the sub-block level face association. For a first sub-block in the current block, the system may identify a first location of the first sub-block. The system may associate the first sub-block with a first face based on the identified first location of the first sub-block. The system may predict a first sample in the first sub-block based on the first face that is associated with the first sub-block.

Abstract: A video encoding device (e.g., a wireless transmit/receive unit (WTRU)) may transmit an encoded frame with a frame sequence number using a transmission protocol. The video encoding device, an application on the video encoding device, and/or a protocol layer on the encoding device may detect a packet loss by receiving an error notification. The packet loss may be detected at the MAC layer. The packet loss may be signaled using spoofed packets, such as a spoofed NAM packet, a spoofed XR packet, or a spoofed ACK packet. A lost packet may be retransmitted at the MAC layer (e.g., by the encoding device or another device on the wireless path). Packet loss detection may be performed in uplink operations and/or downlink operations, and/or may be performed in video gaining applications via the cloud. The video encoding device may generate and send a second encoded frame based on the error notification.

Abstract: Systems, methods, and instrumentalities are disclosed relating to intra prediction of a video signal based on mode-dependent subsampling. A block of coefficients associated with a first sub block of a video block, one or more blocks of coefficients associated with one or more remaining sub blocks of the video block, and an indication of a prediction mode for the video block may be received. One or more interpolating techniques, a predicted first sub block, and the predicted sub blocks of the one or more remaining sub blocks may be determined. A reconstructed first sub block and one or more reconstructed remaining sub blocks may be generated. A reconstructed video block may be formed based on the prediction mode, the reconstructed first sub block, and the one or more reconstructed remaining sub blocks.

Abstract: Processing a 360-degree video content for video coding may include receiving the video content in a first geometry. The video content may include unaligned chroma and luma components associated with a first chroma sampling scheme. The unaligned chroma and luma components may be aligned to a sampling grid associated with a second chroma sampling scheme that has aligned chroma and luma components. A geometric conversion to the video content may be performed. The video content, that may comprise the aligned chroma and luma components, in the first geometry may be converted to a second geometry. The first geometry may be a stitched geometry, and the second geometry may be a coding geometry. The converted video content in the second geometry may include the chroma and luma components aligned to the sampling grid associated with the second chroma sampling scheme.