HlsCaptionSegmentLengthControl

Set Caption segment length control (CaptionSegmentLengthControl) to Match video (MATCH_VIDEO) to create caption segments that align with the video segments from the first video output in this output group. For example, if the video segments are 2 seconds long, your WebVTT segments will also be 2 seconds long. Keep the default setting, Large segments (LARGE_SEGMENTS) to create caption segments that are 300 seconds long.