 Type I conformance point is also assured to fall within the bounds of item i) of clause A.3.1. For conforming bitstreams, all of the following conditions shall be fulfilled for each of the tests: 1. For each access unit n, with n>0, associated with a buffering period SEI message, with Atg,90( specified by Atg,90(n)=90000(t(n)-taf(n-1)) (C-14) the value of nitial_cpb_removal_delay[SchedSelldx] shall be constrained as follows: Rec. ITU-T H.264 (01/2012) If cbr_flag[ SchedSelIdx ] is equal to 0, initial_cpb_removal_delay[ SchedSelIdx (C-15) Otherwise (cbr_flag[ SchedSelIdx ] is equal to 1), Floor( Atg,90( n)) initial_cpb_removal_delay SchedSelIdx Atg,90( (C-16) NOTE 2 - The exact number of bits in the CPB at the removal time of each picture may depend on which buffering period SEI message is selected to initialise the HRD. Encoders must take this into account to ensure that all specified constraints must be obeyed regardless of which buffering period SEI message is selected to initialise the HRD, as the HRD may be initialised at any one of the buffering period SEI messages. 2. A CPB overflow is specified as the condition in which the total number of bits in the CPB is larger than the CPB size. The CPB shall never overflow. 3. A CPB underflow is specified as the condition in which tr,n(n) is less than tar(n). When low_delay_hrd_flag is equal to 0, the CPB shall never underflow. 4. The nominal removal times of pictures from the CPB (starting from the second picture in decoding order), shall satisfy the constraints on tr,(n) and t,(n) expressed in clauses A.3.1 through A.3.3 for the profile and level specified in the bitstream when a coded video sequence conforming to one or more of the profiles specified in Annex A is decoded by applying the decoding process specified in clauses 2-9, and they shall satisfy the constraints on tr,(n) and t,(n) expressed in clauses G.10.2.1 and G.10.2.2 for profile and level specified in the bitstream when a coded video sequence conforming to one or more of the profiles specified in Ann