Stream Buffer Engine Event Codes

Microsoft DirectShow 9.0

Stream Buffer Engine Event Codes

This topic applies only to Windows XP Service Pack 1 or later.

The Stream Buffer Engine posts the following events to the Filter Graph Manager.

Event notification code Description
STREAMBUFFER_EC_CONTENT_BECOMING_STALE The Stream Buffer Source has lagged behind the Stream Buffer Sink by more than a pre-set number of backing files. For more information, see IStreamBufferConfigure::GetBackingFileCount.
STREAMBUFFER_EC_PRIMARY_AUDIO The Stream Buffer Engine is processing primarily audio data. This event is sent if video samples are captured at a very low frame rate. This event most often occurs with audio services on a DVB stream, but it might also indicate a problem with capturing or encoding the video. (Applies to Update Rollup 2 for Microsoft Windows XP Media Center Edition 2005 or later.)
STREAMBUFFER_EC_RATE_CHANGED The playback rate has changed.

param1 = old playback rate x 1000

param2 = new playback rate x 1000

For example, 2x speed is represented as 2000.

STREAMBUFFER_EC_READ_FAILURE A read failure has occurred.

param1 = HRESULT code of the failure

param2 = not used

STREAMBUFFER_EC_STALE_DATA_READ The Stream Buffer Source is reading a backing file that has been marked for deletion.
STREAMBUFFER_EC_STALE_FILE_DELETED A backing file has been deleted.
STREAMBUFFER_EC_TIMEHOLE The Stream Buffer Source filter has reached a gap in the content.

param1 = Time of the start of the gap, in milliseconds, relative to the content start.

param2 = Duration of the gap, in milliseconds.

STREAMBUFFER_EC_WRITE_FAILURE A write failure has occurred.

See Also