SourceBuffer: appendWindowStart property

The appendWindowStart property of the SourceBuffer interface controls the timestamp for the start of the append window, a timestamp range that can be used to filter what media data is appended to the SourceBuffer. Coded media frames with timestamps within this range will be appended, whereas those outside the range will be filtered out.

The default value of appendWindowStart is the presentation start time, which is the beginning time of the playable media.


A double, indicating the start time of the append window, in seconds.


The following exceptions may be thrown when setting a new value for this property:

InvalidAccessError DOMException

Thrown if an attempt was made to set the value to less than 0 or to a value greater than or equal to SourceBuffer.appendWindowEnd.

InvalidStateError DOMException

Thrown if this SourceBuffer object is being updated (i.e. its SourceBuffer.updating property is currently true), or this SourceBuffer has been removed from the MediaSource.




Media Source Extensions™
# dom-sourcebuffer-appendwindowstart

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See also