v2.0.1

Added

• Recognize m4s as a valid extension for init segment (#331). It is used to be
  allowed as the extension for media segments only.
• Improve DASH multi-period support: calculate presentationTimeOffset and
  Period@duration from video segment presentation timestamps. This avoids
  video playback jitters due to gaps.

Fixed

• Handle invalid WebVTT with start_time == end_time gracefully (#335).
• Ignore invalid meta box in mp4 files, which Android's camera app generates
  (#319).
• Set stream duration in init segment for mp4 with static live profile (#340).