Microsoft DirectX 8.1 (C++) |
Note The ICaptureGraphBuilder interface is deprecated.
Sends stream control messages to the pin of the specified category on one or more capture filters in a graph.
Syntax
HRESULT ControlStream(
const GUID *pCategory,
IBaseFilter *pFilter,
REFERENCE_TIME *pstart,
REFERENCE_TIME *pstop,
WORD wStartCookie,
WORD wStopCookie
);
Parameters
pCategory
[in] Pointer to a GUID specifying the output pin category. See Pin Property Set for a list of all pin categories. This value cannot be NULL.
pFilter
[in] Pointer to an IBaseFilter interface on the filter to control. Specifying NULL controls all capture filters in the graph. You will get one notification for each capture filter.
pstart
[in] Pointer to the start time for capture. NULL means start now. MAX_TIME means cancel previous request, or take no action if there is no previous request.
pstop
[in] Pointer to the stop time for capture. NULL means stop now. MAX_TIME means cancel previous request, or take no action if there is no previous request.
wStartCookie
[in] Specifies a particular value to be sent when the start occurs.
wStopCookie
[in] Specifies a particular value to be sent when the stop occurs.
Return Value
Returns S_FALSE if the stop notification is sent before the last sample sent by the capture filter is rendered, otherwise returns S_OK.
If this method returns S_FALSE, the application might want to wait before stopping the filter graph to allow all samples to pass through the graph and be rendered. Otherwise, samples might be lost.
If there are no pins matching the description you provide, or if stream control cannot be supported on all of the indicated pins, this function will return a failure code.
Remarks
Use this method for frame-accurate capture, or for individual control of capture and preview. For example, you could turn off writing of the captured image to disk if you only want to preview the captured image.
This method uses the IAMStreamControl interface on the pins.
This method sends one notification for each filter found with a pin of the specified category.
See Also