IDvbLogicalChannelDescriptor Interface

Microsoft DirectShow 9.0

IDvbLogicalChannelDescriptor Interface

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

The IDvbLogicalChannelDescriptor interface enables the client to get a logical channel descriptor from a DVB stream. The logical channel descriptor may be present in the network information table (NIT).

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

Method Description
GetCountOfRecords Returns the number of records in the logical channel descriptor.
GetLength Returns the length of the descriptor body.
GetRecordLogicalChannelNumber Returns the logical channel number at a specified index in the channel list.
GetRecordServiceId Returns the service identifier at a specified index in the channel list.
GetTag Returns the descriptor tag.


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 logical channel descriptor tag (0x83). If the descriptor is present, the method returns an IGenericDescriptor pointer.
  3. Query the returned IGenericDescriptor pointer for the IDvbLogicalChannelDescriptor interface.


Header: Include dvbsiparser.h.

See Also