Abstract: A method of processing media data. The method includes determining, for a conversion between the media data and a media data file, whether a preselection element includes an indicator, wherein the indicator indicates that video data units representing a target picture-in-picture region of a main video are able to be replaced by corresponding video data units of a supplementary video; and performing the conversion between the media data and the media data file based on the indicator. A corresponding video coding apparatus and non-transitory computer-readable recording medium are also disclosed.

Abstract: Methods and apparatus for processing of video are described. The processing may include video encoding, decoding or transcoding. One example video processing method includes performing a conversion between a video including one or more pictures including one or more subpictures and a bitstream of the video, wherein the bitstream conforms to a format rule that specifies a syntax of network abstraction layer (NAL) units in the bitstream, and wherein the format rule specifies that a NAL unit of a video coding layer (VCL) NAL unit type includes a content associated with a particular type of picture or a particular type of subpicture.

Abstract: A method of digital media processing includes performing a conversion between a media segment and a bitstream of the media segment. The conversion conforming to a format rule and an encryption rule. The format rule specifying that verification information, which includes an indication of an integrity of a portion of the media segment, is signaled in the bitstream.

Abstract: A method of processing media data. The method includes determining, for a conversion between a media data and a media data file, that a preselection element includes an indicator, wherein the indicator indicates which video data units of a main video represent a target picture-in-picture region; and performing the conversion between the media data and the media data file based on the indicator. A corresponding video coding apparatus and non-transitory computer-readable recording medium are also disclosed.

Abstract: A method includes performing a conversion between a video including video pictures that include one or more subpictures and a bitstream of the video. The bitstream conforms to a format rule specifying that one or more syntax structures are constrained based on a constraint flag of a syntax element that includes general constraints information.

Abstract: Methods, devices and systems for configuring different access units in scalable video coding are described. In one example aspect, a method of video processing include performing a conversion between a video including one or more pictures in one or more video layers and a bitstream of a video. The bitstream includes a coded video sequence that includes one or more access units. The bitstream conforms to a format rule that specifies that each access unit of the one or more access units that is a gradual decoding refresh access unit includes exactly one picture for each video layer present in the coded video sequence.

Abstract: A video processing method is provided to include performing a conversion between a video including a plurality of pictures each including at least one slice and a bitstream of the video, wherein the bitstream conforms to a format rule; wherein the format rule specifies that a first flag in the bitstream indicates whether a picture header syntax structure of a picture is included in a slice header of a slice of the picture; and wherein the format rule specifies that, responsive to any of six flags in a picture parameter set associated with the picture is equal to 1, the first flag is equal to 0.

Abstract: A video coding mechanism is disclosed. The mechanism includes partitioning a picture into a plurality of tiles. A number of the tiles are included in a tile group. The mechanism determines whether the tile group is a raster scan tile group or a rectangular tile group. The number of tiles in the tile group is determined based on whether the tile group is the raster scan tile group or the rectangular tile group. The tiles are encoded into a bitstream based on the tile group. The bitstream is stored for communication toward a decoder.

Abstract: Methods, devices and systems for configuring different access units in scalable video coding are described. In one example aspect, a method of video processing include performing a conversion between a video comprising one or more pictures in one or more video layers and a bitstream of a video, wherein the bitstream comprises a coded video sequence that includes one or more access units, and wherein the bitstream further comprises a first syntax element indicating whether an access unit includes a picture for each video layer making up the coded video sequence.

Abstract: A method of processing media data. The method includes determining, for a conversion between the media data and a media data file, that a preselection element includes an indicator, wherein the indicator indicates that a purpose of the preselection element is for providing a picture-in-picture experience where a supplementary video appears to be overlaid on a target picture-in-picture region in a main video; and performing a conversion between the media data and the media data file based on the indicator. A corresponding video coding apparatus and non-transitory computer-readable recording medium are also disclosed.

Abstract: Several techniques for video encoding and video decoding are described. One example method includes performing a conversion between a video block of a video and a bitstream of the video. The video block uses a low frequency non-separable transform for the conversion. The bitstream conforms to a format rule specifying that a syntax element is included at a syntax level for the bitstream. The syntax element is indicative of whether use of a scaling matrix which is derived from a reference scaling list is enabled for the video block. The syntax level is a sequence level, a picture level, or a slice level.

Abstract: A method includes performing a conversion between a video including a video picture and a bitstream of the video according to a rule, wherein the video picture including a subpicture, a tile, and a slice, and wherein the rule specifies that, due to the subpicture including the slice that is partitioned from the tile, the conversion is performed by refraining from counting a height of the subpicture using a number of tiles of the video picture.

Abstract: A method includes performing a conversion between a video including a video picture including one or more tiles and a bitstream of the video. The video picture refers to a picture parameter set, and the picture parameter set conforms to a format rule specifying that the picture parameter set includes a list of column widths for N tile columns, where N is an integer. An (N?1)-th tile column exists in the video picture and the (N?1)-th tile column has a width that is equal to an (N?1)-th entry in a list of explicitly included tile column widths plus one number of coding tree blocks.

Abstract: A method includes making a determination, according to a rule, about whether a height of a subpicture of a video picture of a video is less than a height of a tile row of the video picture; and performing, using the determination, a conversion between the video and a bitstream of the video.

Abstract: A method includes performing a conversion between a video including one or more video pictures and a bitstream of the video, wherein each video picture includes one or more tiles that include one or more tile columns, wherein the bitstream conforms to a format rule, and wherein the format rule specifies that a tile column index is derived for each coding tree unit (CTU) column of a tile of a video picture.

Abstract: A video processing method includes performing a conversion between a video having one or more video layers including one or more video pictures and a bitstream of the video according to a rule. The rule specifies a condition under which no picture that has been generated by a decoding process for generating an unavailable reference picture is referred to by an active entry in a reference picture list of a current slice of a current picture.

Abstract: A method of decoding a coded video bitstream is provided. The method includes obtaining a first reference picture list structure and a second reference picture list structure represented in the coded video bitstream; deriving, based on the first reference picture list structure and the second reference picture list structure, a first reference picture list of a current slice and a second reference picture list of the current slice, wherein the current slice comprises an intra (I) slice or a uni-predictive (P) slice; and obtaining at least one reconstructed block of the current slice following derivation of the first reference picture list and the second reference picture list.

Abstract: A method includes performing a conversion between a video that includes at least a video tile and a bitstream of the video according to a rule. The rule specifies that a height of a slice in the video tile in units of coding tree units is derived based on a value of a first syntax element in the bitstream indicating a number of explicitly provided slice heights for slices in the video tile that includes the slice.

Abstract: A method includes performing a conversion between a video including at least one video picture and a bitstream of the video according to a rule, wherein the at least one video picture includes one or more slices and one or more subpictures, and wherein the rule specifies that an order of slice indices of the one or more slices in the at least one video picture is indicated responsive to a syntax element associated with the at least one picture indicative of whether a single slice is included per subpicture of the at least one video picture.

Abstract: Provided are an electroluminescent compound having a structure represented by Formula I, a thermally activated delayed fluorescence material and an application thereof. The electroluminescent compound has TADF characteristics and may be applied to a light emitting layer of an OLED device as a thermally activated delayed fluorescence material. The OLED device includes an anode, a cathode, and at least one organic thin film layer comprising the thermally activated delayed fluorescence material in a light emitting layer between the anode and the cathode. The electroluminescent compound effectively reduces the overlap between HOMO and LUMO through special molecular structure design, so that ?EST is reduced to less than 0.25 eV, which satisfies reverse crossing of energy from a triplet state to a singlet state, effectively improves transmission capacities of two kinds of carriers, improves carrier balance, and thus significantly improves light emitting efficiency of the OLED device.