| Microsoft DirectX 8.1 (C++) |
The GetDecoderLevel method retrieves the closed-captioned decoder level.
Syntax
HRESULT GetDecoderLevel(
AM_LINE21_CCLEVEL *lpLevel
);
Parameters
lpLevel
Pointer to the retrieved decoder level. AM_L21_CCLEVEL_TC2 (TC2) is the only supported operating channel level and is an enhanced and backward-compatible version of the original TC1 level.
Return Values
Returns an HRESULT value that depends on the implementation of the interface. The current DirectShow implementation returns E_INVALIDARG if a parameter is invalid or NOERROR to indicate success.
Remarks
This method is for informational purposes only.
TC1 and TC2 are television set decoder levels that represent whether the television can handle some closed-captioned byte pairs and produce the desired captioning results. The Line 21 Decoder is capable of TC2 level decoding, which includes all TC1 decoding. Only the first 100,000 television sets manufactured that included closed-captioned capability were TC1 compliant; the later TV sets are TC2 compliant.
See Also