SCTE 104
insert_sub_segment_info
insert_segmentation_descriptor_request_data
When true, the sub_segment_num and sub_segments_expected fields are carried into the resulting SCTE 35 segmentation_descriptor. When false, they are omitted. The flag itself is not passed through. Together with those two fields it can form an optional appendix to the segmentation descriptor, whose presence is determined by the descriptor loop's data_length; the sub-segment fields were added in the SCTE 104 2017 edition.