Athugasemd
Aðgangur að þessari síðu krefst heimildar. Þú getur prófað aðskrá þig inn eða breyta skráasöfnum.
Aðgangur að þessari síðu krefst heimildar. Þú getur prófað að breyta skráasöfnum.
A video capture minidriver uses an extended header in its output streams to provide auxiliary information about the stream and current frame contents. For example, image stream headers provide information about the current frame number, number of dropped frames, and field polarity flags. As each frame is completed, the minidriver fills in the extended header with the auxiliary information about the frame captured.
Stream class video capture minidrivers indicate their ability to provide this additional information for a pin by setting the StreamHeaderMediaSpecific member of the HW_STREAM_OBJECT structure to the sizeof one of the two following structures.
| Structure name | Purpose |
|---|---|
Frame count, drop frame count, field polarity flags, and DirectDraw surface handles. |
|
VBI format, channel change information, video standard. |
If a Stream class minidriver does not provide this additional information, it should set StreamHeaderMediaSpecific to zero.
For more information about when to specify a value in StreamHeaderMediaSpecific, see Stream Categories.