@type t() :: %ExMP4.SampleMetadata{
  dts: pos_integer(),
  duration: pos_integer(),
  offset: pos_integer(),
  pts: pos_integer(),
  size: pos_integer(),
  sync?: boolean(),
  track_id: integer()
}

Sample metadata struct.

• track_id - The track id of the sample.
• dts - The decoding time of the sample in track timescale units.
• pts - The presentation (compoistion) time of the sample in track timescale units.
• sync? - Indicates wether the sample is a sync or rap (random access point).
• duration - The duration of the sample in track timescale units.
• size - The size of the sample.
• offset - The offset of the sample in the container.