A forward error correction (FEC) data generator has an input for at least two datastreams for which FEC data shall be generated in a joint manner, each datastream having a plurality of symbols. A FEC data symbol is based on a FEC source block possibly having a subset of symbols of the at least two data streams. The FEC data generator further has a signaling information generator configured to generate signaling information for the FEC data symbol regarding which symbols within the at least two datastreams belong to the corresponding source block by determining pointers to start symbols within a first and a second datastream, respectively, of the at least two datastreams and a number of symbols within the first datastream and second datastreams, respectively, that belong to the corresponding source block.

A video coding mechanism is disclosed. The mechanism includes a bitstream comprising a parameter set and one or more sub-pictures partitioned from a picture. The parameter set is parsed to obtain a flag indicating that a current sub-picture is a temporal motion constrained sub-picture. The current sub-picture is extracted from the bitstream independently of the picture and based on the flag. The current sub-picture is decoded to create a video sequence. The video sequence is forwarded for display.

A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising a plurality of sub-pictures partitioned from a picture such that a union of the sub-pictures covers a total area of the picture without overlap. The bitstream is parsed to obtain the one or more sub-pictures. The one or more sub-pictures are decoded to create a video sequence. The video sequence is forwarded for display.

A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising a sub-picture partitioned from a picture and a sequence parameter set (SPS) comprising a sub-picture size and a sub-picture location. The SPS is parsed to obtain the sub-picture size of the sub-picture and the sub-picture location of the sub-picture. The sub-picture is decoded based on the sub-picture size and the sub-picture location to create a video sequence. The video sequence is forwarded for display.

A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising one or more sub-pictures partitioned from a picture and a sub-picture level indicator indicating resource requirements for decoding a current sub-picture. The bitstream is parsed to obtain the sub-picture level indicator and the current sub-picture. Resources are allocated to decode the current sub-picture based on the sub-picture level indicator. The current sub-picture is decoded to create a video sequence by employing the allocated resources. The video sequence is forwarded for display.

A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising a sequence parameter set (SPS), one or more sub-pictures partitioned from a picture, and one or more slice headers associated with one or more slices. The SPS is parsed to obtain sub-picture identifiers (IDs) for the one or more sub-pictures. The slice headers are parsed to obtain a current sub-picture ID associated with a current sub-picture. The current sub-picture ID indicating the slices are included in the current sub-picture of the one or more sub-pictures. The current sub-picture is decoded based on the current sub-picture ID to create a video sequence. The video sequence is forwarded for display.

A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising one or more sub-pictures partitioned from a picture such that each sub-picture includes a sub-picture width that is an integer multiple of a coding tree unit (CTU) size when the each sub-picture includes a right boundary that does not coincide with a right boundary of the picture. The bitstream is parsed to obtain the one or more sub-pictures. The one or more sub-pictures are decoded to create a video sequence. The video sequence is forwarded for display.

Aspects of the present disclosure provide techniques for reducing latency and improving image quality of a viewport extracted from multi-directional video communications. According to such techniques, first streams of coded video data are received from a source. The first streams include coded data for each of a plurality of tiles representing a multi-directional video, where each tile corresponding to a predetermined spatial region of the multi-directional video, and at least one tile of the plurality of tiles in the first streams contains a current viewport location at a receiver. The techniques include decoding the first streams and displaying the tile containing the current viewport location. When the viewport location at the receiver changes to include a new tile of the plurality of tiles, retrieving and decoding first streams for the new tile, displaying the decoded content for the changed viewport location, and transmitting the changed viewport location to the source.

Aspects of the present disclosure provide techniques for reducing latency and improving image quality of a viewport extracted from multi-directional video communications. According to such techniques, first streams of coded video data are received from a source. The first streams include coded data for each of a plurality of tiles representing a multi-directional video, where each tile corresponding to a predetermined spatial region of the multi-directional video, and at least one tile of the plurality of tiles in the first streams contains a current viewport location at a receiver. The techniques include decoding the first streams and displaying the tile containing the current viewport location. When the viewport location at the receiver changes to include a new tile of the plurality of tiles, retrieving and decoding first streams for the new tile, displaying the decoded content for the changed viewport location, and transmitting the changed viewport location to the source.

Methods are provided for reducing the size of a transpose buffer used for computation of a two-dimensional (2D) separable transform. Scaling factors and clip bit widths determined for a particular transpose buffer size and the expected transform sizes are used to reduce the size of the intermediate results of applying the 2D separable transform. The reduced bit widths of the intermediate results may vary across the intermediate results. In some embodiments, the scaling factors and associated clip bit widths may be adapted during encoding.