Methods and apparatus for video processing are disclosed. The processing may include video encoding, video decoding, or video transcoding. One example method includes performing a conversion between a current block of a video and a bitstream of the video. The bitstream conforms to a rule that specifies that a context index offset is used for including a first sign flag of a first coefficient in the bitstream. The rule specifies that a value of the context index offset is based on whether a first coding mode is applied on the current block in the bitstream.

Methods and apparatus for video processing are disclosed. The processing may include video encoding, video decoding, or video transcoding. One example method includes performing a conversion between a current block of a video and a bitstream of the video. The bitstream conforms to a rule that specifies that a context index offset is used for including a first sign flag of a first coefficient in the bitstream. The rule specifies that a value of the context index offset is based on whether a first coding mode is applied on the current block in the bitstream.

Methods and apparatus for video processing are described. The processing may include video encoding, video decoding, or video transcoding. An example video processing method includes performing a conversion between a video and a bitstream of the video including one or more output layer sets according to a format rule. At least one of the one or more output layer sets consists of a trick mode access representation including only intra random access points pictures or only intra-coded pictures. The format rule specifies whether or how level information for the trick mode representation is indicated in the bitstream.

Methods and apparatus for video processing are described. The processing may include video encoding, video decoding, or video transcoding. An example video processing method includes performing a conversion between a video and a bitstream of the video including one or more output layer sets according to a format rule. At least one of the one or more output layer sets consists of a trick mode access representation including only intra random access points pictures or only intra-coded pictures. The format rule specifies whether or how level information for the trick mode representation is indicated in the bitstream.

A method for deriving a value for a first syntax element, Syntax_A. The method comprises determining whether Syntax_A is present in a bitstream. The method comprises, as a result of determining that Syntax_A is not present in the bitstream, deriving the value for Syntax_A to be equal to a first value, B, if a first condition is satisfied, or deriving the value for Syntax_A to be equal to a second value, C, if a second condition is satisfied.

A method for deriving a value for a first syntax element, Syntax_A. The method comprises determining whether Syntax_A is present in a bitstream. The method comprises, as a result of determining that Syntax_A is not present in the bitstream, deriving the value for Syntax_A to be equal to a first value, B, if a first condition is satisfied, or deriving the value for Syntax_A to be equal to a second value, C, if a second condition is satisfied.

Methods and apparatuses of encoding a video stream using video point cloud coding include determining a projection plane for each point in the point cloud; creating a list of raw points included in the point cloud; generating a list of connected components; determining whether a number of connected components is greater than a first threshold; based on determining that the number of the connected components is greater than the first threshold, processing the connected components and generating one or more patches based on the processed connected components; and generating an encoded video stream based on the generated one or more patches, wherein the list of raw points is updated based on at least one from among a result of the generating of the list of connected components, and a result of the processing of the connected components.

Methods and apparatuses of encoding a video stream using video point cloud coding include determining a projection plane for each point in the point cloud; creating a list of raw points included in the point cloud; generating a list of connected components; determining whether a number of connected components is greater than a first threshold; based on determining that the number of the connected components is greater than the first threshold, processing the connected components and generating one or more patches based on the processed connected components; and generating an encoded video stream based on the generated one or more patches, wherein the list of raw points is updated based on at least one from among a result of the generating of the list of connected components, and a result of the processing of the connected components.

A three-dimensional data encoding method includes: encoding divided data items to generate encoded data items each corresponding to a respective one of the divided data items, the divided data items being included in subspaces obtained by dividing a current space including three-dimensional points, the divided data items each including one or more three-dimensional points among the three-dimensional points; and generating a bitstream including the encoded data items and control information items each corresponding to a respective one of the encoded data items. Each of the control information items includes a first identifier and a second identifier. The first identifier indicates a subspace corresponding to an encoded data item corresponding to the control information item, and the second identifier indicates a divided data item corresponding to the encoded data item corresponding to the control information item.

A three-dimensional data encoding method includes: encoding divided data items to generate encoded data items each corresponding to a respective one of the divided data items, the divided data items being included in subspaces obtained by dividing a current space including three-dimensional points, the divided data items each including one or more three-dimensional points among the three-dimensional points; and generating a bitstream including the encoded data items and control information items each corresponding to a respective one of the encoded data items. Each of the control information items includes a first identifier and a second identifier. The first identifier indicates a subspace corresponding to an encoded data item corresponding to the control information item, and the second identifier indicates a divided data item corresponding to the encoded data item corresponding to the control information item.