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IDvbTerrestrialDeliverySystemDescriptor Interface

 
Microsoft DirectShow 9.0

IDvbTerrestrialDeliverySystemDescriptor Interface

This topic applies to Update Rollup 2 for Microsoft Windows XP Media Center Edition 2005 and later.

The IDvbTerrestrialDeliverySystemDescriptor interface enables the client to get a terrestrial delivery system descriptor from a DVB stream. The terrestrial delivery system descriptor may be present in the network information table (NIT). For more information, refer to ETSI EN 300 468.

In addition to the methods inherited from IUnknown, the IDvbTerrestrialDeliverySystemDescriptor interface exposes the following methods.

Method Description
GetBandwidth Returns the bandwidth in use.
GetCentreFrequency Returns the center frequency.
GetCodeRateHPStream Returns the code rate for the high-priority (HP) stream.
GetCodeRateLPStream Returns the code rate for the low-priority (LP) stream.
GetConstellation Returns the constellation pattern.
GetGuardInterval Returns the guard interval.
GetHierarchyInformation Returns the hierarchy alpha information.
GetLength Returns the length of the descriptor body.
GetOtherFrequencyFlag Returns a flag that specifies whether other frequencies are in use.
GetTag Returns the descriptor tag.
GetTransmissionMode Returns the transmission mode.

Remarks

To obtain a pointer to this interface, do the following:

  1. Call IDvbSiParser::GetNIT to get the IDVB_NIT interface.
  2. Call IDVB_NIT::GetRecordDescriptorByTag and pass in the terrestrial delivery system descriptor tag (0x5A). If the descriptor is present, the method returns an IGenericDescriptor pointer.
  3. Query the returned IGenericDescriptor pointer for the IDvbTerrestrialDeliverySystemDescriptor interface.

Requirements

Header: Include dvbsiparser.h.

See Also