2.2.4.4 TfxdBox
The TfxdBox field and related fields encapsulate the absolute timestamp and duration of a fragment in a live presentation. This field SHOULD be ignored if it appears in an on-demand presentation.
TfxdBox (variable): The metadata container for per-sample defaults.
TfxdBoxLength (4 bytes): The length of the TfxdBox field, in bytes, including the TfxdBoxLength field. If the value of the TfxdBoxLength field is %00.00.00.01, the TfxdBoxLongLength field MUST be present.
TfxdBoxLongLength (8 bytes): The length of the TfxdBox field, in bytes, including the TfxdBoxLongLength field.
TfxdBoxVersion (1 byte): The box version. If this field contains the value %x01, the TfxdBoxDataFields64 field MUST be present inside the TfxdBoxFields field. Otherwise, the TfxdBoxDataFields32 field MUST be present inside the TfxdBoxFields field.
FragmentAbsoluteTime32 (4 bytes): The absolute timestamp of the first sample of the fragment, in timescale increments for the track.
FragmentDuration32 (4 bytes): The total duration of all samples in the fragment, in timescale increments for the track.
FragmentAbsoluteTime64 (8 bytes): The absolute timestamp of the first sample of the fragment, in timescale increments for the track.
FragmentDuration64 (8 bytes): The total duration of all samples in the fragment, in timescale increments for the track.
The syntax of the fields that are defined in this section, specified in ABNF [RFC5234], is as follows.
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TfxdBox = TfxdBoxLength TfxdBoxType [TfxdBoxLongLength] TfxdBoxUUID TfxdBoxFields TfxdBoxChildren TfxdBoxType = %d117 %d117 %d105 %d100 TfxdBoxLength = BoxLength TfxdBoxLongLength = LongBoxLength TfxdBoxUUID = %x6D %x1D %x9B %x05 %x42 %xD5 %x44 %xE6 %x80 %xE2 %x14 %x1D %xAF %xF7 %x57 %xB2 TfxdBoxFields = TfxdBoxVersion TfxdBoxFlags TfxdBoxDataFields32 / TfxdBoxDataFields64 TfxdBoxVersion = %x00-01 TfxdBoxFlags = 24*24RESERVED-BIT TfxdBoxDataFields32 = FragmentAbsoluteTime32 FragmentDuration32 TfxdBoxDataFields64 = FragmentAbsoluteTime64 FragmentDuration64 FragmentAbsoluteTime32 = UNSIGNED-INT32 FragmentDuration32 = UNSIGNED-INT32 FragmentAbsoluteTime64 = UNSIGNED-INT64 FragmentDuration64 = UNSIGNED-INT64 TfxdBoxChildren = *( VendorExtensionUUIDBox )