Partager via

IDvbFrequencyListDescriptor Interface

  • Article
 
Microsoft DirectShow 9.0

IDvbFrequencyListDescriptor Interface

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

The IDvbFrequencyListDescriptor interface enables the client to get a frequency list descriptor from a DVB stream. The frequency list 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 IDvbFrequencyListDescriptor interface exposes the following methods.

Method Description
GetCodingType Returns a flag that specifies how the frequency is coded.
GetCountOfRecords Returns the number of records in the frequency list descriptor.
GetLength Returns the length of the descriptor body.
GetRecordCentreFrequency Returns the frequency at a specified index in the frequency list.
GetTag Returns the descriptor tag.

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 frequency list descriptor tag (0x62). If the descriptor is present, the method returns an IGenericDescriptor pointer.
  3. Query the returned IGenericDescriptor pointer for the IDvbFrequencyListDescriptor interface.

Requirements

Header: Include dvbsiparser.h.

See Also