Microsoft DirectX 9.0

Microsoft Unified Tuning Model Interfaces

These interfaces are used primarily by guide store loaders, to create tune requests for an EPG database (guide store), and by applications that install custom tuning spaces on a system. Applications can also use these interfaces to:

Create or modify a tune request dynamically.
Test the validity of a tuning space.
Create a default preferred components list that indicates user preferences for options such as the audio stream language.
Examine the components (such as audio substreams) available on a specified service.

For more information, see The Microsoft Unified Tuning Model.

Tuning Space Interfaces

These interfaces manage tuning space objects. You will never use the base class ITuningSpace interface directly; you will always use a derived interface that is specific to a particular network type.

Interface	Description
IAnalogRadioTuningSpace	Represents a tuning space for analog radio networks. (Not implemented in this release.)
IAnalogTVTuningSpace	Represents a tuning space for analog TV networks.
IATSCTuningSpace	Represents a tuning space for ATSC networks.
IAuxInTuningSpace	Represents a tuning space for S-video or composite video inputs.
ICreatePropBagOnRegKey	Creates a property bag for saving a default tune request to the system registry.
IDVBSTuningSpace	Represents a tuning space for satellite DVB (DVB-S) networks.
IDVBTuningSpace	Represents a tuning space for DVB networks.
IDVBTuningSpace2	Represents a tuning space for DVB networks; extends the IDVBTuningSpace interface.
IEnumTuningSpaces	Standard COM enumeration interface for tuning spaces.
IMPEG2TuneRequestFactory	Creates a minimal MPEG-2 tune request for a specified tuning space.
ITuningSpace	Base interface for all tuning spaces.
ITuningSpaceContainer	Provides access to all of the tuning spaces installed on the host system.
ITuningSpaces	Represents a collection of tuning spaces.

Tune Request Interfaces

Tune requests are not created directly. They are obtained through a call to CreateTuneRequest on a network-specific tuning space interface, such as IDVBTuningSpace.

Interface	Description
IATSCChannelTuneRequest	Provides tuning information specific to ATSC TV networks.
IChannelTuneRequest	Provides tuning information specific to analog TV networks.
IDVBTuneRequest	Provides tuning information specific to DVB TV networks.
IMPEG2TuneRequest	Represents a minimal MPEG-2 tune request.
ITuneRequest	Provides tuning information relevant for all network types.

Stream Component Interfaces

A "component" in this context refers to a substream within a broadcast. Applications create a default preferred components collection based on user input, in order to specify, for example, a preferred audio stream language. When an audio stream is specified in this way, the Network Provider will always attempt to use it for all tune request in the tuning space (See ITuningSpace::put_DefaultPreferredComponentTypes.) In some cases the actual components of a broadcast stream can only be discovered after reception begins, or the actual components may differ from what was advertised in the EPG information. At that time the BDA Network Provider will fill in the Component information in the tune request, and the application can then retrieve it and use it, for example, to change the audio stream or determine which audio streams are currently available.

Interface	Description
IATSCComponentType	Provides a method that indicates whether the audio substream is in AC-3 format.
IComponent	Base class for all derived component interfaces.
IComponents	Provides a standard COM enumeration of components.
IComponentType	Base class for all derived component type interfaces.
IComponentTypes	Provides a standard COM enumeration of component types.
IEnumComponents	Implemented on a standard COM collection object containing all the active or inactive components on the current broadcast stream.
ILanguageComponentType	Provides methods that describe the language of the substream.
IMPEG2ComponentType	Provides methods that describe a component type associated with an MPEG-2 stream type.

Locator Interfaces

Locators are used by the Network Provider and other filters in the graph to determine how to locate a specified program. These interfaces are not used by applications except possibly for debugging purposes. Third parties that install new tuning spaces should also provide a default locator for the tuning space. An individual tune request contains a locator, which can be different from the default locator. If present, the locator in the tune request takes precedence over the default locator

Interface	Description
IATSCLocator	Provides tuning information for an ATSC network.
IDVBCLocator	Provides tuning information for a DVB-C network.
IDVBSLocator	Provides tuning information for a DVB-S network.
IDVBTLocator	Provides tuning information for a DVB-T network.
ILocator	Base interface for all derived locator interfaces. Not used directly.