g SEI message applies. The bitstream may or may not contain access units with temporal_idequalto sei_temporal_i When the scalable nesting SEI message contains one or more SEI messages with payloadTyp not equal to 0 or 1, sei_temporal_id shall be equal to the value of temporal_io for the access unit associated with the scalable nesting SEI message. For an nested SEI message with payloadType not equal to 0 or 1, the values of i_dependency_id[i sei_quality_id and sei temporal_io present in or inferred for the associated scalable nesting SEI message, indicate the values of dependency_ quality_id, and temporal_id, respectively, of the VCL NAL units to which the nested SEI message applies. sei_nesting_zero_bit shall be equal to 0. G.13.2.8 Base layer temporal HRD SEI message semantics The base layer temporal HRD SEI message provides HRD parameters for subsets of the base layer bitstream. The base layer temporal HRD SEI message shall not be included in a scalable nesting SEI message. The base layer temporal HRD SEI message shall not be present in access units that do not contain VCL NAL units of the primary coded picture with nal_unit_type equal to 5. When present, this SEI message applies to the target access unit set that consists of the current access unit and all subsequent access units in decoding order until, but excluding, the next access unit containing a NAL unit of the primary coded picture with nal_unit_type equal to 5 (if present) or the end of the bitstream (otherwise). aum_of_temporal_layers_in_base_layer_minus1 plus 1 specifies the number of bitstream subsets inside the target access unit set for which the following syntax elements are specified in the base layer temporal HRD SEI message. The value of aum_of_temporal_layers_in_base_layer_minus1 shall be in the range of 0 to 7, inclusive. sei_temporal_ id| ] specifies the temporal id value of the i-th bitstream subset. When i is greater than 0, the value of sei_temporal_ id| shall not be equal to any of the values of sei_temporal_id[j with j =0..(i-1). = A