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This specification defines a Media Source Extensions byte stream format specification based on MPEG-2 Transport Streams.
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This specification defines segment formats for implementations that choose to support MPEG-2 Transport Streams (MPEG-2 TS) specified in ISO/IEC 13818-1.
It defines the MIME-type parameters used to signal codecs, and provides the necessary format specific definitions for initialization segments, media segments, and random access points required by the byte stream formats section of the Media Source Extensions spec. This document also defines extra behaviors and state that only apply to this byte stream format.The MIME-type/subtype pair of "video/MP2T", as specified in RFC 3551, MUST be used for byte streams that conform to this specification.
This following parameters can be used in the MIME-type passed to isTypeSupported() or addSourceBuffer().
MPEG-2 TS media and initialization segments MUST conform to the MPEG-2 TS Adaptive Profile (ISO/IEC 13818-1:2012 Amd. 2).
The user agent MUST run the append error algorithm with the decode error parameter set to true if any of the following conditions are met:
An MPEG-2 TS initialization segment consists of a single PAT and a single PMT.
The user agent MUST run the append error algorithm with the decode error parameter set to true if any of the following conditions are met:
The user agent MUST accept and ignore other SI, such as CAT, that are invariant for all subsequent media segments.
The user agent MUST source attribute values for id, kind, label and language for AudioTrack, VideoTrack and
TextTrack objects as described for MPEG-2 Transport Streams in the in-band tracks spec [INBANDTRACKS].
The user agent MUST run the append error algorithm with the decode error parameter set to true if any of the following conditions are met:
A random access point as defined in this specification corresponds to Elementary Stream Random Access Point as defined in ISO/IEC 13818-1.
Timestamp rollovers and discontinuities MUST be handled by the UA. The UA's MPEG-2 TS implementation MUST maintain an internal offset
variable, MPEG2TS_timestampOffset, to keep track of the offset that needs to be applied to timestamps
that have rolled over or are part of a discontinuity. MPEG2TS_timestampOffset is initially set to 0 when the SourceBuffer is
created. This offset MUST be applied to the timestamps as part of the conversion process from MPEG-2 TS packets
into coded frames for the coded frame processing algorithm. This results in the coded frame timestamps
for a packet being computed by the following equations:
Coded Frame Presentation Timestamp = (MPEG-2 TS presentation timestamp) + MPEG2TS_timestampOffset
Coded Frame Decode Timestamp = (MPEG-2 TS decode timestamp) + MPEG2TS_timestampOffset
MPEG2TS_timestampOffset is updated in the following ways:
abort() is called, MPEG2TS_timestampOffset MUST be set to 0.timestampOffset is successfully set, MPEG2TS_timestampOffset MUST be set to 0.As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.
The key words MAY, MUST, and SHOULD are to be interpreted as described in [RFC2119].