g is equal to 1, the following conditions shall be fulfilled as follows: If t1 is not equal to t2, the following condition shall be true: average_bit_rate == ( * 1000) ) (D-10) Otherwise (t1 is equal to t2), the following condition shall be true: average_bit_rate ==0 (D-11) average_frame_rate indicates the average frame rate in units of frames/(256 seconds) of the target sub-sequence. All NAL units of the target sub-sequence are taken into account in the calculation. The average frame rate is derived according to the access unit removal time specified in clause C.1.2. In the following, fC is the number of frames, complementary field pairs and non-paired fields in the sub-sequence. t1 is the removal time (in seconds) of the first access unit of the sub-sequence (in decoding order), and t2 is the removal time (in seconds) of the last access unit of the sub-sequence (in decoding order). When accurate_statistics_flag is equal to 1, the following conditions shall be fulfilled as follows: If t1 is not equal to t2, the following condition shall be true: average_frame_rate ==Round(fC*25 (t2-t1) (D-12) Otherwise (t1 is equal to t2), the following condition shall be true: average_frame_rate ==0 (D-13) Rec. ITU-T H.264 (01/2012) num_referenced_subseqs specifies the number of sub-sequences that contain pictures that are used as reference pictures for inter prediction in the pictures of the target sub-sequence. num_referenced_subseqs shall be in the range of 0 to 255, inclusive. ref_sub_seq_layer_num, ref_sub_seq_id, and ref_sub_seq_direction identify the sub-sequence that contains pictures that are used as reference pictures for inter prediction in the pictures of the target sub-sequence. Depending on ref_sub_seq_direction, the following applies: If ref_sub_seq_direction is equal to 0, a set of candidate sub-sequences consists of the sub-sequences which have a value of sub_seq_id equal to ref_sub_seq_id, which reside in the sub-sequence layer having sub_seq_layer_num equal to ref_sub_seq_layer_num, and for which the first pi