SCTE 35 Part 1
pts_time
splice_time · Time90kHz
The intended splice time in ticks of the 90 kHz clock. Add pts_adjustment to this value, then the splice happens at the first PES packet whose PTS reaches that adjusted time (the sum wraps at 2 to the 33rd). At an Out Point the splice time refers to the point just before the first qualifying presentation unit, while at an In Point it refers to that unit itself (clause 9.9.2.1).