| Microsoft DirectX 9.0 |
The IFrequencyMap interface sets the frequency table used by the BDA Network Provider filter.
A frequency table is a list of broadcast or cable frequencies for a given country/region. The Network Provider uses a frequency table to find the next frequency when IScanningTuner methods are called. On startup, the Network Provider loads a default frequency table. An application can use the IFrequencyMap interface to specify the user's country/region, which causes the Network Provider filter to load the corresponding frequency table. The application can also modify the current table, or provide a completely new table, using the put_FrequencyMapping method.
Frequencies used by this interface are measured in units of kilohertz (kHz), and refer to the center frequency of each band. For more information, see "Terrestrial delivery system descriptor" in EN 300 468.
Note Currently only the DVB-T Network Provider supports this interface.
In addition to the methods inherited from IUnknown, the IFrequencyMap interface exposes the following methods.
| Method | Description |
| get_CountryCode | Returns the country/region code that the Network Provider is currently using. |
| get_CountryCodeList | Returns a list of all the country/region codes for which the Network Provider has a frequency table. |
| get_DefaultFrequencyMapping | Returns the default frequency table for a given country/region code. |
| get_FrequencyMapping | Returns the Network Provider filter's current frequency table. |
| put_CountryCode | Sets the country/region code. |
| put_FrequencyMapping | Sets the frequency table. |