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Tables and Assignments

 
Microsoft DirectShow 9.0

Tables and Assignments

This section contains the following frequency tables for international analog TV tuning:

Frequency Tables

Worldwide, there is a finite, known set of broadcast frequency standards. These standards have been identified by their country/region of origin, but in many cases, multiple countries/regions share the same standard. The TV Tuner filter defines a table for each standard.

However, there is no finite, known set of cable frequency standards. The cable providers in some countries/regions are free to broadcast programming on frequencies of their choosing. Frequencies from multiple standards are often mixed. In most cases, this practice correlates directly with the country/region of origin for each of the frequency standards. The TV Tuner filter defines tables for the few cable standards (and countries/regions) that have dependable cable frequency allocations. For all others, it uses the Unicable Frequency Table.

The frequency tables in the following sections are extracted verbatim from the resource file definitions that were used to build the tables in the TV Tuner filter. Each table starts with its resource ID. You can use these resource IDs to cross-reference from the Country/Region Assignments table, to determine which tables are in use for each country/region or locale.

The frequency tables include the theoretical upper and lower channel numbers (or frequency indexes) for each country/region code. This range can be extended by using the registry; for more information, see Frequency Overrides.