File formats and parsing and coding of video data are defined to promote more efficient random accessibility of coded video data. Constraints may be imposed on placement of parameter sets and the definition of sync samples in video files. Parameter set data for video data may be coded, for a non-sync sample, only in the sample entry for the sample, the sample, a previous sample in decoding order that is a sync sample, or in a sample occurring in decoding order between the sample and the previous sample in decoding order that is a sync sample.

An example client device for retrieving media data includes a memory configured to store media data; and one or more processors implemented in circuitry and configured to execute a plurality of video decoders; determine a complexity value for the media data including a plurality of encoded video streams, the complexity value representing complexity of an aggregation of the encoded video streams; retrieve the media data including the encoded video streams in response to determining that the client device is capable of decoding the encoded video streams using the complexity value; and distribute the encoded video streams and synchronization information to corresponding video decoders of the plurality of video decoders to cause the video decoders to decode the corresponding video streams and to output decoded video data from the video streams in a synchronized fashion.

A device for processing video data can be configured to receive a configuration record for decoding a bitstream of the video data, wherein the configuration record for the bitstream includes a toolset indication syntax element that includes information identifying, from a set of video decoding tools, tools that are required to decode the bitstream associated with the configuration record; based on the toolset indication syntax element, determine whether to retrieve the bitstream associated with the configuration record; and based on the determination to retrieve the bitstream associated with the configuration record, retrieve the bitstream and outputting the bitstream to a video decoder for decoding.

A receiving method of receiving a first data unit in which data making up an encoded stream is stored and the first data unit stores a plurality of second data units. The receiving method includes: receiving the first data unit, first time information indicating a presentation time of the first data unit, second time information indicating, together with the first time information, a presentation time or a decoding time of each of the plurality of second data units, and identification information; calculating the presentation time or the decoding time of each of the plurality of second data units using the first time information and the second time information; and correcting the presentation time or the decoding time of each of the plurality of second data units based on the identification information.

Methods and device for encoding/decoding data representative of a 3D scene. To reach that aim, first data representative of texture of the 3D scene visible according to a first viewpoint is encoded into one or more first tracks, the first data being arranged in first tiles of a first frame, a part of the 3D scene being associated with each first tile; second data representative of depth associated with points of the 3D scene is encoded into one or more second tracks, the second data being arranged in second tiles of a second frame, the total number of second tiles being greater than the total number of first tiles, a set of second tiles being allocated to each first tile and patches are arranged in the set of second tiles a set, each patch corresponding to a two-dimensional parametrization of a group of 3D points comprised into the part of the 3D scene associated with each first tile and comprising second data representative of depth associated with the 3D points of the group; and instructions to extract at least a part of the first data and second data from at least a part of the at least a first track and at least a second track are further encoded into one or more third tracks.

Systems, methods and apparatus for encoding or decoding a file format that stores one or more images are described. One example method includes performing a conversion between a visual media file and a bitstream of a visual media data according to a format rule, where the bitstream includes one or more output layer sets and one or more parameter sets that include one or more profile tier level syntax structures, where at least one of the profile tier level syntax structures includes a general constraints information syntax structure, where the format rule specifies that a syntax element is included in a configuration record in the visual media file, and where the syntax element indicates a profile, a tier, or a level to which an output layer set identified by an output layer set index indicated in the configuration record conforms.

Systems, methods and apparatus for encoding or decoding a file format that stores one or more images are described. One example method includes performing a conversion between a visual media file and a bitstream of a visual media data according to a format rule, wherein the format rule specifies a characteristic of a syntax element in the visual media file, wherein the syntax element has a value that is indicative of a number of bytes used for indicating a constraint information associated with the bitstream.

Systems, methods and apparatus for encoding or decoding a file format that stores one or more images are described. One example method includes performing a conversion between a visual media file and a bitstream of a visual media data according to a format rule, wherein the format rule specifies a characteristic of a syntax element in the visual media file, and wherein the format rule specifies that the syntax element that has a value indicative of a level identification is coded in any one or both of a subpicture common group box or a subpicture multiple groups box using eight bits.

Systems, methods and apparatus for visual media data processing are described. One method includes performing a conversion between a visual media data and a visual media file that stores a bitstream of the visual media data in multiple tracks according to a format rule that specifies that the file-level information includes a syntax element that identifies one or more tracks from the multiple tracks that contain a specific type of sample group that includes operation point information.

Systems, methods and apparatus for storing or parsing a visual media file according a file format include performing a conversion between a visual media data and a visual media file that stores a bitstream of the visual media data according to a format rule. The visual media file stores one or more tracks comprising one or more video layers. The format rule specifies that whether a first set of syntax elements indicative of layer dependency information is stored in the visual media file is dependent on whether a second syntax element indicating that all layers in the visual media file are independent has a value 1.