arameter set within the slice headers of each picture. Sequence parameter sets are used in the decoding processes of other NAL units as determined by reference to a sequence parameter set within the picture parameter sets of each sequence. No normative decoding process is specified for NAL units with nal_unit_type equal to 6, 9, 10, 11, and 12. Rec. ITU-T H.264 (01/2012) Slice decoding process 8.2.1 Decoding process for picture order count Outputs of this process are TopFieldOrderCnt (if applicable) and BottomFieldOrderCnt (if applicable). Picture order counts are used to determine initial picture orderings for reference pictures in the decoding of B slices (see clauses 8.2.4.2.3 and 8.2.4.2.4), to determine co-located pictures (see clause 8.4.1.2.1) for deriving motion parameters in temporal or spatial direct mode, to represent picture order differences between frames or fields for motion vector derivation in temporal direct mode (see clause 8.4.1.2.3), for implicit mode weighted prediction in B slices (see clause 8.4.2.3.2), and for decoder conformance checking (see clause C.4). Picture order count information is derived for every frame, field (whether decoded from a coded field or as a part of a decoded frame), or complementary field pair as follows: Each coded frame is associated with two picture order counts, called TopFieldOrderCnt and BottomFieldOrderCnt for its top field and bottom field, respectively. Each coded field is associated with a picture order count, called TopFieldOrderCnt for a coded top field and BottomFieldOrderCnt for a bottom field. Each complementary field pair is associated with two picture order counts, which are the TopFieldOrderCnt for its coded top field and the BottomFieldOrderCnt for its coded bottom field, respectively. TopFieldOrderCnt and BottomFieldOrderCnt indicate the picture order of the corresponding top field or bottom field relative to the first output field of the previous IDR picture or the previous reference picture including a memory_management_control_operation equal