# US 12,120,354 B2 · Scalable nesting SEI messages for specified layers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,120,354 B2 - Document ID: US12120354B2 - Status: Granted - Kind: B2 - Application number: 17/702,032 - Filed: 2022-03-23 - Published: 2022-07-07 - Granted: 2024-10-15 - Earliest claimed: 2019-09-24 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Ye-Kui Wang - Web page: https://patentgrep.com/patent/US12120354B2 ## CPC - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N 19/172: the region being a picture, frame or field - H04N 19/187: the unit being a scalable video layer - H04N 19/188: {the unit being a video data packet, e.g. a network abstraction layer [NAL] unit} - H04N 19/30: using hierarchical techniques, e.g. scalability (H04N19/63 takes precedence) - H04N 19/46: Embedding additional information in the video signal during the compression process (H04N19/517, H04N19/68, H04N19/70 take precedence) - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A video coding mechanism is disclosed. The mechanism includes encoding a bitstream comprising one or more layers. A scalable nesting supplemental enhancement information (SEI) message is encoded into the bitstream in a current SEI network abstraction layer (NAL) unit. The scalable nesting SEI message contains one or more scalable-nested SEI messages and one or more scalable nesting layer identifiers (Ids) that specify layer Id values of the layers to which the scalable-nested SEI messages apply except a layer Id value of the current SEI NAL unit. A set of bitstream conformance tests are performed on the layers based on the scalable-nested SEI messages. The bitstream is stored for communication toward a decoder. ## Claims ### Claim 1 A method implemented in a decoder, the method comprising: receiving a bitstream comprising one or more layers and a scalable nesting supplemental enhancement information (SEI) message in a current SEI network abstraction layer (NAL) unit, wherein the scalable nesting SEI message contains one or more scalable-nested SEI messages and one or more scalable nesting layer identifiers (Ids) that specify layer Id values of the layers to which the scalable-nested SEI messages apply except a layer Id value of the current SEI NAL unit; deriving a number of nesting layers (nestingNumLayers) variable that specifies a number of layers to which the scalable-nested SEI messages apply; deriving a list of nesting layer Ids (NestingLayerId[i]) that specifies a list of nuh_layer_id values of the layers to which the scalable-nested SEI messages apply for i in a range of zero to nestingNumLayers minus one, inclusive; and decoding a coded picture from the one or more layers to produce a decoded picture, wherein the nestingNumLayers and the NestingLayerId[i] are derived as follows: if( scalable nesting all_layers_flag ) { nestingNumLayers = vps_max_layers_minus1 + 1 − GeneralLayerIdx[ nuh_layer_id ] for( i = 0; i < nestingNumLayers; i ++) NestingLayerId[ i ] = vps_layer_id[ GeneralLayerIdx[ nuh_layer_id ] + i ] } else { nestingNumLayers = scalable nesting num_layers_minus1 + 1 for( i = 0; i < nestingNumLayers; i ++) NestingLayerId[ i ] = (i = = 0 ) ? nuh_layer_id : scalable nesting layer_id[ i ] } where scalable nesting all_layers_flag specifies whether the scalable-nested SEI messages apply to all layers that have a NAL unit header layer Id (nuh_layer_id) greater than or equal to a nuh_layer_id of a current SEI NAL unit, vps_max_layers_minus1 plus one specifies a number of layers specified by a video parameter set (VPS), GeneralLayerIdx is a variable specifying a layer index of a layer with nuh_layer_id equal to vps_layer_id[i], vps_layer_id[i] specifies a nuh_layer_id value of an i-th layer, and scalable nesting num_layers_minus1 plus one specifies a number of layers to which the scalable-nested SEI messages apply. ### Claim 2 (depends on 1) The method of claim 1, wherein the scalable nesting layer Ids are a scalable nesting layer_id[i] syntax element that specifies a nuh_layer_id value of an i-th layer to which the scalable-nested SEI messages apply when a scalable nesting all layers flag (all_layers_flag) is equal to zero. ### Claim 3 (depends on 2) The method of claim 2, wherein each value of scalable nesting layer_id[i] is greater than a nuh_layer_id value of the current SEI NAL unit. ### Claim 4 (depends on 1) The method of claim 1, wherein scalable nesting num_layers_minus1 is in a to range of zero vps_max_layers_minus1-GeneralLayerIdx[nuh_layer_id], inclusive, where nuh_layer_id is the nuh_layer_id of the current SEI NAL unit. ### Claim 5 (depends on 1) The method of claim 1, wherein the coded picture is decoded based on the scalable nested SEI messages. ### Claim 6 (depends on 1) The method of claim 1, wherein the scalable nesting SEI message includes at least one scalable-nested SEI message that applies to a layer of the current SEI NAL unit. ### Claim 7 A method implemented in an encoder, the method comprising: encoding a bitstream comprising one or more layers; encoding into the bitstream a scalable nesting supplemental enhancement information (SEI) message in a current SEI network abstraction layer (NAL) unit, wherein the scalable nesting SEI message contains one or more scalable-nested SEI messages and one or more scalable nesting layer identifiers (Ids) that specify layer Id values of the layers to which the scalable-nested SEI messages apply while applying a constraint to omit a layer Id value of the current SEI NAL unit; performing a set of bitstream conformance tests on the layers based on the scalable-nested SEI messages; and storing the bitstream for communication toward a decoder, wherein performing the set of bitstream conformance tests further comprises: deriving a number of nesting layers (nestingNumLayers) variable that specifies a number of layers to which the scalable-nested SEI messages apply; and deriving a list of nesting layer Ids (NestingLayerId[i]) that specifies a list of nuh_layer_id values of the layers to which the scalable-nested SEI messages apply for i in a range of zero to nestingNumLayers minus one, inclusive, wherein the nestingNumLayers and the NestingLayerId[i] are derived as follows: if( scalable nesting all_layers_flag ) { nestingNumLayers = vps_max_layers_minus1 + 1 − GeneralLayerIdx[ nuh_layer_id ] for( i = 0; i < nestingNumLayers; i ++) NestingLayerId[ i ] = vps_layer_id[ GeneralLayerIdx[ nuh_layer_id ] + i ] } else { nestingNumLayers = scalable nesting num_layers_minus1 + 1 for( i = 0; i < nestingNumLayers; i ++) NestingLayerId[ i ] = (i = = 0 ) ? nuh_layer_id : scalable nesting layer_id[ i ] } where scalable nesting all_layers_flag specifies whether the scalable-nested SEI messages apply to all layers that have a NAL unit header layer Id (nuh_layer_id) greater than or equal to a nuh_layer_id of a current SEI NAL unit, vps_max_layers_minus1 plus one specifies a number of layers specified by a video parameter set (VPS), GeneralLayerIdx is a variable specifying a layer index of a layer with nuh_layer_id equal to vps_layer_id[i], vps_layer_id[i] specifies a nuh_layer_id value of an i-th layer, and scalable nesting num_layers_minus1 plus one specifies a number of layers to which the scalable-nested SEI messages apply. ### Claim 8 (depends on 7) The method of claim 7, wherein the scalable nesting layer Id is a scalable nesting layer_id[i] syntax element that specifies a nuh_layer_Id value of an i-th layer to which the scalable-nested SEI messages apply when a scalable nesting all layers flag (all_layers_flag) is equal to zero. ### Claim 9 (depends on 8) The method of claim 8, wherein each value of scalable nesting layer_id[i] is greater than a nuh_layer_id value of the current SEI NAL unit. ### Claim 10 (depends on 7) The method of claim 7, wherein scalable nesting num_layers_minus1 is in a range of zero to vps_max_layers_minus1-GeneralLayerIdx[nuh_layer_id], inclusive, where nuh_layer_id is the nuh_layer_id of the current SEI NAL unit. ### Claim 11 (depends on 7) The method of claim 7, wherein the scalable nesting SEI message includes at least one scalable-nested SEI message that applies to a layer of the current SEI NAL unit. ### Claim 12 A video coding device comprising: a receiver configured to receive a bitstream comprising one or more layers and a scalable nesting supplemental enhancement information (SEI) message in a current SEI network abstraction layer (NAL) unit, wherein the scalable nesting SEI message contains one or more scalable-nested SEI messages and one or more scalable nesting layer identifiers (Ids) that specify layer Id values of the layers to which the scalable-nested SEI messages apply except a layer Id value of the current SEI NAL unit; and a processor coupled to the receiver and configured to: derive a number of nesting layers (nestingNumLayers) variable that specifies a number of layers to which the scalable-nested SEI messages apply; derive a list of nesting layer Ids (NestingLayerId[i]) that specifies a list of nuh layer id values of the layers to which the scalable-nested SEI messages apply for i in a range of zero to nestingNumLayers minus one, inclusive; and decode a coded picture from the one or more layers to produce a decoded picture, wherein the nestingNumLayers and the NestingLayerId[i] are derived as follows: if(scaleable nesting all_layers_flag)} nestingNumLayers=vps_max_layers_minus1+1−GeneralLayerIdx[nuh_layer_id] for(i=0; i