RESTRICTIONS ON GRADUAL DECODING REFRESH (GDR) UNIT

摘要

Methods, devices and systems for video coding and encoding, which include constraints, restrictions and signaling for subpictures, slices, and tiles, are described. One example method of video processing includes performing a conversion between a video comprising one or more pictures and a bitstream of the video, wherein the bitstream conforms to a format rule, wherein the format rule disallows coding of a picture of the one or more pictures to include a coded slice network abstraction layer (NAL) unit having a gradual decoding refresh type and to associate with a flag indicating that the picture contains mixed types of NAL units.