Selecting from Multiple Input Devices of the Same Type

This topic applies to Windows XP Home Edition and Windows XP Professional only.

It is possible that some systems may have more than one TV tuner card, even multiple cards of the same type. To handle this case, the application should provide the user a way to specify which particular piece of hardware to use when building the filter graph. An application retrieves the collection of available TV tuner devices on the system by specifying a GUID for each device category it is interested in. Currently two categories are supported. The application enables the user to select the active device by using the Video Control's InputActive property.

The Video Control recognizes the class ID strings for TV tuner device categories listed in the following table.

The following example shows how to obtain a collection of available BDA-compatible tuning devices. For the sake of simplicity, this code just sets the first item in the collection as the active input.

Dim objInputs
Set objInputs = MSVidCtl.InputsAvailable("{71985F4B-1CA1-11D3-9CC8-00C04F7971E0}")
MSVidCtl.InputActive = objInputs(0)