Scalable nesting SEI messages for specified layers

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.

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<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.