## Time Stamps

For more information about time stamps, see section 2.4.1 of ISO1-11172: "The packet header may contain decoding and/or presentation time stamps (DTS and PTS) that refer to the first access unit in the packet."

For MPEG_Stream major types, the start time is the byte position of the first byte, rated at 1 byte per second. The stop time is the byte position of the last byte. Thus, consecutive samples should have the stop time of the first packet equal to the start time of the next packet. For Video CD data, the origin of the medium must match the format of a video-CD file exposed by CDFS with the standard RIFF chunk at the start.

For MPEG video packet and payload types, the time stamp is the presentation time for the first video frame whose picture start code begins in the sample.

For MPEG audio packet and payload types, the time stamp is the presentation time for the first audio frame whose sync code starts in the sample.

It is assumed that packet and payload data without time stamps can be successfully prerolled by the handling filters.

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