IMFSensorDevice::GetStreamAttributesCount method (mfidl.h)

Article
02/22/2024

Gets the count of stream attribute stores for the sensor device. This number represents the number of total streams available for the device because every valid stream must have an attribute store that contains at least the stream ID and stream category.

Syntax

HRESULT GetStreamAttributesCount(
  [in]  MFSensorStreamType eType,
  [out] DWORD              *pdwCount
);

Parameters

[in] eType

A member of the MFSensorStreamType enumeration specifying whether the attribute store count is being requested for an input or output stream.

[out] pdwCount

The number of stream attributes available for this sensor device.

Return value

The method returns an HRESULT. Possible values include, but are not limited to, those in the following table.

Return code	Description
S_OK	The method succeeded.
E_POINTER	The pdwCount parameter is null.
MF_E_NOT_INITIALIZED	The sensor group has not been initialized.

Remarks

The caller can use the number of stream attributes to indicate the number of streams provided by the sensor device.

Note Depending on the sharing mode in which the sensor device was activated, not all streams may be present during runtime. Streams marked as shared, i.e. with the MF_DEVICESTREAM_FRAMESERVER_SHARED attribute set to non-zero value, and streams with pins with the category PINNAME_VIDEO_PREVIEW will be present in devices that are set to used shared mode. Put a device in shared mode by passing MFSensorDeviceMode_Shared into SetSensorDeviceMode. If no streams are marked as shared and no preview stream is available, the first capture stream, with the category PINNAME_VIDEO_CAPTURE, will be shared.

Requirements

Requirement	Value
Minimum supported client	Windows 10, version 1607 [desktop apps only]
Minimum supported server	None supported
Target Platform	Windows
Header	mfidl.h
Library	Mfplat.lib; Mfplat.dll