Abstract: A method includes performing a conversion between a current slice of a current picture of a video and a bitstream of the video, wherein the bitstream conforms to a format rule, and wherein the format rule specifies that a general constraint information syntax structure, which comprises one or more constraint flags indicating constraints on an explicit weighted prediction being enabled for slices of a set of pictures, is present.

Abstract: A method of video processing includes performing a conversion between a video and a bitstream of the video. The bitstream includes one or more output layer sets each comprising one or more video layers. The bitstream conforms to a format rule, wherein the format rule specifies that a number of decoded picture buffer parameter syntax structures included in a video parameter set for the bitstream is equal to: zero, in a case that each output layer set includes a single video layer; or one plus a value of a syntax element, in a case that each output layer set includes a single layer is not true.

Abstract: Several techniques for video encoding and video decoding are described. One example method includes performing a conversion between a video and a bitstream of the video including one or more output layer sets (OLSs) according to a rule. The rule specifies that a subpicture level information (SLI) supplemental enhancement information (SEI) message includes information about a level of subpicture sequences in a set of coded video sequences of the one or more OLSs to which the SLI SEI message applies. A syntax structure of the SLI SEI message includes at least (1) a first syntax element specifying a maximum number of sublayers for the subpicture sequences and (2) a second syntax element specifying whether level information for the subpicture sequences is present for one or more sublayer representations.

Abstract: Examples of video encoding methods and apparatus and video decoding methods and apparatus are described. An example method of video processing includes performing a conversion between a video and a bitstream of the video according to a rule, wherein the bitstream includes network abstraction layer (NAL) units for multiple video layers according to a rule; wherein the rule defines that a sub-bitstream extraction process to generate an output bitstream comprising an output layer set (OLS) includes one or more operations that are selectively performed responsive to the following conditions: (1) a list of NAL unit header layer identifier values in the OLS does not includes all values of NAL unit header layer identifiers in all video coding layer (VCL) NAL units in the bitstream, and (2) the output bitstream containing a supplemental enhancement information (SEI) NAL unit that contains a scalable-nesting SEI message.

Abstract: Methods, apparatus, systems for performing video processing such as video encoding, video decoding or video transcoding are described. One example method of video processing includes performing a conversion between a video comprising one or more video layers and a bitstream of the video according to a rule. The rule specifies that responsive to a value of a first field in a sequence parameter set (SPS) that is referred to by a video layer, a second field in a video parameter set referred to by the SPS that is indicative of a maximum number of sublayers allowed in the bitstream is construed to be equal to a third field in the SPS. The third field is indicative of a maximum number of sublayers allowed in the video layer.

Abstract: Methods, systems, and devices for signaling of general constraint information are described. An example method of video processing includes performing a conversion between a video including one or more pictures and a bitstream of the video according to a rule. The rule specifies that a syntax structure in a profile-tier-level syntax structure is after a syntax element. The syntax structure includes information related to general constraint information (GCI) for the bitstream. The syntax element indicates a level to which an output layer set associated with the profile-tier-level syntax structure conforms.

Abstract: A video processing method is provided to include performing a conversion between a video and a bitstream of the video, wherein the bitstream conforms to a format rule, and wherein the format rule specifies a condition that controls whether or how one or more syntax elements related to picture order counts for a long term reference picture are included in a reference picture list syntax structure in the bitstream.

Abstract: Methods, systems, and devices for picture output ordering constraints in video bitstreams are described. An example method of video processing includes performing a conversion between a video including one or more pictures and a bitstream of the video according to a rule, wherein the rule specifies that the bitstream includes at least a first picture that is output, wherein the first picture is in an output layer, wherein the first picture includes a syntax element equaling one, and wherein the syntax element affects a decoded picture output and a removal process associated with a hypothetical reference decoder (HRD).

Abstract: A method of decoding a coded video bitstream is provided. The method includes receiving a bitstream containing an external decoder refresh (EDR) picture and a list of pictures for the EDR picture. The list of pictures lists pictures referred to by entries in a first reference picture list, pictures referred to by entries in a second reference picture list, and external pictures in increasing decoding order. A difference between picture order count values for any two consecutive pictures in the list of pictures is greater than one half of a negative of maximum picture order count least significant bits and less than one half of the maximum picture order count least significant bits. The method further includes obtaining an external picture from the the external pictures referred to in the list of pictures and decoding the EDR picture using the external picture that was obtained.

Abstract: A method of decoding a coded video bitstream is provided. The method includes parsing a parameter set represented in the coded video bitstream. The parameter set contains a set of syntax elements that include a set of reference picture list structures. The method also includes parsing a slice header of a current slice represented in the coded video bitstream. The slice header contains an index of a reference picture list structure among the set of reference picture list structures in the parameter set. The method further includes deriving, based on the set of syntax elements in the parameter set and the index of the reference picture list structure, a reference picture list of the current slice. The method also includes obtaining, based on the reference picture list, at least one reconstructed block of the current slice.

Abstract: A method for implementing an adaptive colour transform (ACT) mode during image/video encoding and decoding includes performing a conversion between a current video block of a video and a bitstream of the video, wherein the current video block is coded using the ACT mode, wherein the conversion comprises applying an inverse ACT transform on the current video block according to a rule, and wherein the rule specifies that a clipping operation, based on a bit depth of the current video block, is applied to an input of the inverse ACT transform.

Abstract: Several embodiments for video encoding and video decoding are described. An example method of processing video data includes performing a conversion between a video including one or more subpictures and a bitstream of the video, wherein one or more supplemental enhancement information messages that have filler payloads are processed during the conversion according to a format rule, and wherein the format rule disallows the one or more supplemental enhancement information messages having filler payloads to be in a scalable nesting supplemental enhancement information message.

Abstract: A method for determining a productivity of a coalbed methane well without shutting down the well includes steps of: obtaining coalbed methane basic data; based on PVT experimental data, determining a relationship table between a pressure and a coalbed methane deviation factor, and a relationship table between the pressure and a pseudo-pressure; recording daily gas production rates, bottomhole flow pressures, and cumulative gas productions at each stabilized flow pressure test moment in at least three different production stages; determining formation pressures corresponding to each stabilized flow pressure test moment based on a material balance equation; according to the formation pressures, the bottomhole flow pressures and the production rates, determining coefficients in a deliverability equation of the coalbed methane well for determining the deliverability equation; substituting the formation pressures and the bottomhole flow pressures into the deliverability equation for obtaining corresponding product

Abstract: 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.

Abstract: A method of video data processing includes performing a conversion between a video and a bitstream of the video. The bitstream comprises multiple layers comprising one or more subpictures according to a rule which specifies that, during a subpicture sub-bitstream extraction process by which an output bitstream is extracted from the bitstream, a supplemental enhancement information (SEI) network abstraction layer (NAL) unit that includes a scalable nested SEI message that is not applicable to the output bitstream is omitted in the output bitstream.

Abstract: Systems, methods and apparatus for video processing are described. The video processing may include video encoding, video decoding, or video transcoding. One example method of video processing includes performing a conversion between a video and a bitstream of the video according to a format rule. The format rule specifies that constraints on values of one or more first syntax elements in an adaptation parameter set are defined based on semantics of second syntax elements in a picture header and/or a slice header when a picture or a slice referring to the adaptation parameter set.

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 format rule. The format rule specifies that a first video picture is an associated intra random access point picture of a second picture and that the second picture are constrained to belong to a same video layer.

Abstract: A surface cleaning device includes a nozzle and an odor dial assembly. The nozzle includes a nozzle housing and a dirty air passageway. The odor dial assembly include a fragrance member and a dial body configured to be removably coupled to the nozzle housing. The dial body at least partially defines a fragrance cavity configured to at least partially receive the fragrance member and a fragrance passageway extending therethrough. The odor dial assembly is configured to transition between a plurality of user-selectable positions to adjust an amount of fragrance particles released by the fragrance member into the dirty air passageway.

Abstract: Examples of video encoding methods and apparatus and video decoding methods and apparatus are described. An example method of video processing includes performing a conversion between a current picture of a video and a bitstream of the video according to a rule. The rule specifies that responsive to a picture being referred to by an inter-layer reference picture (ILRP) entry in a reference picture list of a slice of the current picture, the picture is allowed to have a gradual decoding refresh (GDR) type and a syntax element specifying a recovery point of the picture in an output order is 0.

Abstract: Embodiments of this application disclose a data protection method and system, a medium, and an electronic device, and belong to the field of communication technologies. In embodiments of this application, a first electronic device establishes a communication connection to a second electronic device. The first electronic device is a trusted device of the second electronic device. When detecting a first trigger condition, the first electronic device sends first data to the second electronic device. The first data is used to trigger the second electronic device to enter a maintenance mode. According to embodiments of this application, the first electronic device triggers the second electronic device to enter the maintenance mode, to protect data of the electronic devices.