Sample Properties


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Sample Properties

MPEG samples have the following properties or notifications.

Time stamp Not all samples have start and stop times. The sample stop time for packet and payload data is not useful; it is usually set to the start time plus one. MPEG packet or payload data samples will have a start and stop time set if the system layer packet they are generated from had a valid PTS.
Discontinuity If there is a break in the stream (for example, a gap in the real-time data, or an error in the data or after a seek), the Discontinuity property is set. This property is propagated from the MPEG-1 splitter to the stream handlers in the first sample sent after this property is set in a sample received. This also allows for a time-stamp discontinuity.
End Of Stream This is not a sample property but a separate notification. When this is received, any buffered data must be forced through the decoder. Logically, any new data must then start with the Discontinuity property.

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Time stamp	Not all samples have start and stop times. The sample stop time for packet and payload data is not useful; it is usually set to the start time plus one. MPEG packet or payload data samples will have a start and stop time set if the system layer packet they are generated from had a valid PTS.
Discontinuity	If there is a break in the stream (for example, a gap in the real-time data, or an error in the data or after a seek), the Discontinuity property is set. This property is propagated from the MPEG-1 splitter to the stream handlers in the first sample sent after this property is set in a sample received. This also allows for a time-stamp discontinuity.
End Of Stream	This is not a sample property but a separate notification. When this is received, any buffered data must be forced through the decoder. Logically, any new data must then start with the Discontinuity property.