A video processing method includes performing a conversion between a video comprising one or more pictures and a bitstream of the video according to a format rule. The format rule specifies that, in response to satisfying one or more conditions, a syntax element indicating whether a first syntax structure providing a profile, a tier and a level information and a second syntax structure providing decoded picture buffer information are present in a sequence parameter set is set to be equal to 1 to indicate that the first syntax structure and the second syntax structure are present in the sequence parameter set.

A video processing method includes performing a conversion between a video comprising one or more pictures and a bitstream of the video according to a format rule. The format rule specifies that, in response to satisfying one or more conditions, a syntax element indicating whether a first syntax structure providing a profile, a tier and a level information and a second syntax structure providing decoded picture buffer information are present in a sequence parameter set is set to be equal to 1 to indicate that the first syntax structure and the second syntax structure are present in the sequence parameter set.

A video processing method includes performing a conversion between a video comprising a video unit and a bitstream of the video according to a rule. The rule specifies whether or how to include, in an adaptation parameter set (APS), information related to a scaling list of the video is based on a first syntax element. The first syntax element indicates whether the APS includes chroma component related syntax elements and is independent of one or more syntax elements in a sequence parameter set (SPS).

Methods and apparatuses for video coding are provided. The method includes that a decoder determines whether a disable flag is present in a picture header (PH) associated with a picture, wherein the disable flag specifies whether a coding tool is disabled in one or more slices associated with the PH. Additionally, the method includes that the decoder infers value of the disable flag according to one or more enable flags signaled in a sequence parameter set (SPS) of the picture in response to determining that the disable flag is not present in the PH, inferring, by the decoder.

Methods and apparatuses for video coding are provided. The method includes that a decoder determines whether a disable flag is present in a picture header (PH) associated with a picture, wherein the disable flag specifies whether a coding tool is disabled in one or more slices associated with the PH. Additionally, the method includes that the decoder infers value of the disable flag according to one or more enable flags signaled in a sequence parameter set (SPS) of the picture in response to determining that the disable flag is not present in the PH, inferring, by the decoder.

A video processing method includes checking, during a conversion from a coded representation of a current video block to the current video block, a position of a last non-zero coefficient of the current video block, wherein the position is relative to a top-left position of the current video block; and performing a determination, based on the position, whether or not to parse a syntax element which signals a transform information in the coded representation.

Disclosed herein includes a system, a method, and a device for reducing latency and jitter by reserving a transmission duration for a transmit opportunity. A device can compress a first slice of a plurality of slices of a video frame to obtain a size of the first slice after compression. The device can estimate a size of the video frame after compression, according to the size of the first slice after compression. The device can generate a request to send (RTS) to reserve, a transmission channel for a transmission duration corresponding to the size of the video frame after compression. The device can broadcast the RTS to one or more other devices.

Disclosed herein includes a system, a method, and a device for reducing latency and jitter by reserving a transmission duration for a transmit opportunity. A device can compress a first slice of a plurality of slices of a video frame to obtain a size of the first slice after compression. The device can estimate a size of the video frame after compression, according to the size of the first slice after compression. The device can generate a request to send (RTS) to reserve, a transmission channel for a transmission duration corresponding to the size of the video frame after compression. The device can broadcast the RTS to one or more other devices.

Systems, methods, and instrumentalities for sub-block motion derivation and motion vector refinement for merge mode may be disclosed herein. Video data may be coded (e.g., encoded and/or decoded). A collocated picture for a current slice of the video data may be identified. The current slice may include one or more coding units (CUs). One or more neighboring CUs may be identified for a current CU. A neighboring CU (e.g., each neighboring CU) may correspond to a reference picture. A (e.g., one) neighboring CU may be selected to be a candidate neighboring CU based on the reference pictures and the collocated picture. A motion vector (MV) (e.g., collocated MV) may be identified from the collocated picture based on an MV (e.g., a reference MV) of the candidate neighboring CU. The current CU may be coded (e.g., encoded and/or decoded) using the collocated MV.

Systems, methods, and instrumentalities for sub-block motion derivation and motion vector refinement for merge mode may be disclosed herein. Video data may be coded (e.g., encoded and/or decoded). A collocated picture for a current slice of the video data may be identified. The current slice may include one or more coding units (CUs). One or more neighboring CUs may be identified for a current CU. A neighboring CU (e.g., each neighboring CU) may correspond to a reference picture. A (e.g., one) neighboring CU may be selected to be a candidate neighboring CU based on the reference pictures and the collocated picture. A motion vector (MV) (e.g., collocated MV) may be identified from the collocated picture based on an MV (e.g., a reference MV) of the candidate neighboring CU. The current CU may be coded (e.g., encoded and/or decoded) using the collocated MV.