Abstract: In certain aspects of the disclosure, a method, a computer-readable medium, and a system for foveated rendering of omnidirectional media content are provided. The method includes receiving a request to access a stream of media data associated with the omnidirectional media content at a point in time the client is accessing the stream of media data for foveated rendering of the omnidirectional media content; determining an initial portion of media data, starting from the point in time the client requests to access, for foveated rendering of the omnidirectional media content for delivery to a client device; and transmitting, in response to the request, the initial portion of media data. The initial portion of media data comprises a portion of the omnidirectional media content for a viewport that is foveated rendered or to be displayed using foveated rendering on the client device according to the request.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to encode and/or decode video data. Immersive media data includes a first patch track comprising first encoded immersive media data that corresponds to a first spatial portion of immersive media content, a second patch track comprising second encoded immersive media data that corresponds to a second spatial portion of the immersive media content that is different than the first spatial portion, an elementary data track comprising first immersive media elementary data, wherein the first patch track and/or the second patch track reference the elementary data track, and grouping data that specifies a spatial relationship between the first patch track and the second patch track. An encoding and/or decoding operation is performed based on the first patch track, the second patch track, the elementary data track and the grouping data to generate decoded immersive media data.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to generate media data for an immersive media experience. A set of parameters for processing a scene description for an immersive media experience are accessed. Multimedia data for the immersive media experience is accessed, including a plurality of media tracks, each media track comprising an associated series of samples of media data for a different component of the immersive media experience, and a derived track comprising a set of derivation operations to perform to generate a series of samples of media data for the client for the immersive media experience. A derivation operation is performed to generate a portion of media data for a derived media track, including processing the plurality of media tracks to generate a first series of samples of the media data for the immersive media experience, and outputting the derived media track.

Abstract: Method and apparatus for signaling or parsing constrained active entries in reference picture lists for multi-layer coding are disclosed. For the decoder side, when the current picture is a RADL (Random Access Decodable Leading) picture, reference picture list 0 or reference picture list 1 of the current picture is mandatorily required to contain no active entry corresponding to a RASL (Random Access Skipped Leading) picture with pps_mixed_nalu_types_in_pic_flag equal to 0 or a picture that precedes an associated IRAP (Intra Random Access Point) picture in decoding order, and wherein an active entry in the reference picture list 0 or the reference picture list 1 of the RADL picture can refer to a RASL picture with the pps_mixed_nalu_types_in_pic_flag equal to 1 and a referenced RASL picture either belongs to the same layer or a different layer than a layer containing the current picture which is the RADL picture.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to encode and/or decode video data. Immersive media data includes a set of one or more tracks, each track comprising associated immersive media data corresponding to an associated spatial portion of immersive media content and metadata specifying a six degree of freedom (6DoF) viewing region in the immersive media content, wherein the metadata comprises viewing region type data indicating a type of the viewing region. An encoding and/or decoding operation is performed based on the set of one or more tracks and the viewing region metadata to generate encoded and/or decoded immersive media data. The viewing region type data can be specified by a data structure attribute of the metadata specifying a viewing region and/or by an attribute of the metadata specifying a viewing region.

Abstract: A method for specifying layout of subpictures is provided. A video decoder receives data from a bitstream to be decoded as a current picture of a video. The video decoder parses the bitstream for positions and sizes of multiple subpictures of the current picture. A position of a first subpicture and a size of a last subpicture are skipped during the parsing. The video decoder reconstructs the current picture and the subpictures of the current picture according to the positions and the sizes of the subpictures.

Abstract: A method for performing transform skip mode (TSM) in a video decoder is provided. A video decoder receives data from a bitstream to be decoded as a plurality of video pictures. The video decoder parses the bitstream for a first syntax element in a sequence parameter set (SPS) of a current sequence of video pictures. When the first syntax element indicates that transform skip mode is allowed for the current sequence of video pictures and when transform skip mode is used for a current block in a current picture of the current sequence, the video decoder reconstructs the current block by using quantized residual signals that are not transformed.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to access media data for a first three-dimensional (3D) immersive media experience including media tracks each including an associated series of samples of media data for a different component of the first 3D immersive media experience and derived immersive tracks, each comprising a set of derivation operations to perform to generate an associated series of samples of media data for a different component of a second 3D immersive media experience and perform, for each of the one or more derived immersive tracks, a derivation operation of the set of derivation operations by processing associated samples of the one or more media tracks as specified by the derivation operation to generate the associated series of samples of media data of the second 3D immersive media experience.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to accessing multimedia data that includes a plurality of media tracks that each include an associated series of samples of media data, and a derived track comprising a set of derivation operations to perform to generate a series of samples of media data for the derived track. A derivation operation of the set is performed to generate a portion of media data for the derived track, which includes: determining, based on the derivation operation, a group of media tracks from the plurality by determining each media track in the group meets a grouping criteria, selecting one media track from the group of media tracks, and adding a sample from the one media track to the derived track to generate the portion of the derived track.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to access multimedia data comprising a hierarchical track structure comprising at least a first track at a first level of the hierarchical track structure comprising first media data, wherein the first media data comprises a first sequence of video media units, and a second track at a second level in the hierarchical track structure different than the first level of the first track, the second track comprising metadata specifying a re-timing derivation operation. Output video media units are generated according to the second track, comprising performing the re-timing derivation operation on the first sequence of video media units to modify a timing of the first sequence of video media units by removing one or more video media units associated with the re-timing derivation operation and/or shifting timing information of the first sequence of video media units.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to provide video data for immersive media implemented by a server in communication with a client device. A request to access a stream of media data associated with immersive content at a point in time the client is first accessing the stream of media data for the immersive content is received from the client device. In response to the request from the client, the server transmits a response indication whether it has rendered at least part of the stream of media data. The server may also determine, based on the request from the client, whether to render at least part of the stream of media data for delivery to the client device.

Abstract: A method and system of multimedia streaming services using DASH (Dynamic Adaptive Streaming over HTTP) are disclosed. According to this method, one or more Push Directives are sent from a client to a server to indicate information related to media data requested. Each Push Directive comprises a Push type including Push-rate and Push-rate Directive includes information associated with a push data rate related to the media data requested. If the Push-rate Directive is received by the server, one or more groups of data for the media data requested are pushed from the server to the client according to the push data rate. According to another method, fragmented MPDS are used, where at least one fragmented MPD omits a MPD header, MPD payload, Period header or Period payload. In yet another method, a status message group includes SharedResourceAllocation message that comprises parameters including bandwidth and pacingRate.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to perform media processing tasks. A media processing entity includes a processor in communication with a memory, wherein the memory stores computer-readable instructions that, when executed by the processor, cause the processor to perform receiving, from a remote computing device, multi-view multimedia data comprising a hierarchical track structure comprising at least a first track comprising first media data at a first level of the hierarchical track structure, and a second track comprising task instruction data at a second level in the hierarchical track structure that is different than the first level of the first track. The instructions further cause the processor to perform processing the first media data of the first track based on the task instruction data of the second track to generate modified media data and an output track that includes the modified media data.

Abstract: Video processing methods and apparatuses for processing a current block in a current picture by reference picture resampling include receiving input data of the current block, determining a scaling window of the current picture and a scaling window of a reference picture. The current picture and reference picture may have different scaling window sizes. A ratio between a scaling window width, height, or size of the current picture and a scaling window width, height, or size of the reference picture is constrained to be within a ratio constraint. A reference block is generated from the reference picture according to the ratio, and used to encode or decode the current block.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to provide video data for immersive media implemented by a server in communication with a client device. A request to access a stream of media data associated with immersive content at a point in time the client is first accessing the stream of media data for the immersive content is received from the client device. An initial portion of media data is determined, starting from the point in time the client requests to access, for the immersive content for delivery to the client device. In response to the request to access the stream of media data, the initial portion of media data is transmitted to the client device.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to perform media processing. A media processing entity includes at least one processor in communication with a memory, wherein the memory stores computer-readable instructions that, when executed by the at least one processor, cause the at least one processor to perform receiving, from a remote computing device, multi-view multimedia data comprising a hierarchical track structure comprising at least a first track comprising first media data at a first level of the hierarchical track structure, and metadata associated with a second track at a second level in the hierarchical track structure that is different than the first level of the first track. The instructions further cause the processor to perform processing the first media data of the first track based on the metadata associated with the second track to generate second media data for the second track.

Abstract: Methods and apparatus for video coding are disclosed. According to one method, a bitstream is generated or received, where the bitstream includes a first syntax and a second syntax. The first syntax is related to a target number of bits used to represent a set of third syntaxes and each third syntax specifies one subpicture ID for one subpicture in a set of subpictures. The second syntax is related to a total number of subpictures in the set of subpicture, where a first number that can be represented by the target number of bits is equal to or greater than the total number of subpictures. According to another method, the subpicture ID syntaxes have different values for different subpictures.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to accessing multimedia data that includes a plurality of media tracks that each include an associated series of samples of media data, and a derived track comprising a set of derivation operations to perform to generate a series of samples of media data for the derived track. A derivation operation of the set is performed to generate a portion of media data for the derived track, which includes: determining, based on the derivation operation, a group of media tracks from the plurality by determining each media track in the group meets a grouping criteria, selecting one media track from the group of media tracks, and adding a sample from the one media track to the derived track to generate the portion of the derived track.

Abstract: Methods and apparatuses for processing video data include receiving input data associated with a current video picture, dividing the current video picture into non-overlapping rectangular tiles, grouping the tiles in the current video picture into tile groups, and encoding or decoding video data in the tile groups within the current video picture. According to one embodiment, each tile group is composed of an integer number of tiles, and shapes of all the tile groups are constrained to be rectangle. According to one embodiment, a flag is used to indicate whether one or more in-loop filtering operations are performed across tile group boundaries.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to encode and/or decode video data. Point cloud video data includes a plurality of tracks. first metadata of a first track of the plurality of tracks, the first metadata specifying a first source region of a plurality of source regions of the point cloud video data, wherein each source region corresponds to a different spatial portion of the point cloud video data. The first metadata specifies a sub-region of the first track in the first source region comprising data indicative of a spatial position of video data of the first track in the first source region. Point cloud media is generated, based on the first metadata, for the sub-region of the first source region using the video data of the first track.