nits from the CPB and output timing from the DPB are specified in the picture timing SEI message as specified in clauses D.1.2 and D.2.2. All timing information relating to a specific access unit shall arrive prior to the CPB removal time of the access unit. When the coded video sequence conforms to one or more of the profiles specified in Annex G and the decoding process specified in Annex G is applied, the following is specified: (a) When an access unit contains one or more buffering period SEI messages that are included in scalable nesting SEI messages and are associated with values of DQId in the range of ( (DQIdMax >4) to ( DQIdMax + inclusive, the last of these buffering period SEI messages in decoding order is the buffering period SEI message that initialises the HRD. Let hrdDQId be the largest value of 16 sei_dependency_id[ sei_quality_id[ that is associated with the scalable nesting SEI message containing the buffering period SEI message that initialises the HRD, let hrdDId and hrdQId be equal to hrdDQId >> 4 and hrdDQId & 15, respectively, and let hrdTId be the value of sei_temporal_i that is associated with the scalable nesting SEI message containing the buffering period SEI message that initialises the HRD. (b) The picture timing SEI messages that specify the removal timing of access units from the CPB and output timing from the DPB are the picture timing SEI messages that are included in scalable nesting SEI messages associated with values of dependency_id[ sei_quality_id[i], and sei_temporal_io equal to hrdDId, hrdQId, and hrdTId, respectively. (c) The HRD parameter sets that are used for conformance checking are the HRD parameter sets, included in the SVC video usability information extension of the active SVC sequence parameter set, that are associated with values of vui_ext_dependency_id[i vui_ext_quality_id[i and rui_ext_temporal_id[i equal to hrdDId, hrdQId, and hrdTId, respectively. For the specification in this annex, num_units_in_tick, time_scale, Rec. ITU-T H.264 (01/2012) fixed_frame_rate_