DD_DXAPI_OPENVIDEOPORT control code
A video capture driver passes DD_DXAPI_OPENVIDEOPORT in the dwFunctionNum parameter of the DxApi function to notify the kernel-mode video transport that the driver requires a hardware video port.
Input Parameters
- lpvInBuffer
Pointer to a DDOPENVIDEOPORTIN structure that contains the DirectDraw VPE object information.
Output Parameters
- lpvOutBuffer
Pointer to a DDOPENVIDEOPORTOUT structure that contains the new VPE object handle information.
Remarks
The object is specified by the dwVideoPortHandle member of DDOPENVIDEOPORTIN, which is the hardware video port ID specified when the VPE object was created in user mode. The hDirectDraw member of DDOPENVIDEOPORTIN specifies the DirectDraw object with which the video port is associated. The driver must also specify a callback that is called when the VPE object becomes unusable due to it being released at user mode. The pContext member of DDOPENVIDEOPORTIN contains a value that is passed if the pfnVideoPortClose callback function is ever called.
If the ddRVal member of DDOPENVIDEOPORTOUT is set to DD_OK, the output from this function identifier is a new DirectDraw surface handle. This new handle must be used on all subsequent calls that reference this VPE object.
This function identifier can only be called from PASSIVE_LEVEL.
Requirements
Header file: Ddkmapi.h (include Ddkmapi.h)