IWMEncAudioSource::get_PreProcessPass
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The get_PreProcessPass method retrieves the preprocess pass count.
Syntax
HRESULT get_PreProcessPass(
short* piPassesCount
);
Parameters
piPassesCount
[out] Pointer to a short that indicates the number of passes to make (0 or 1) for preprocessing.
Return Values
If the method succeeds, it returns S_OK. If it fails, it supports the IErrorInfo interface and returns an HRESULT error code.
| Return code | Number | Description |
| E_POINTER | 0x80004003 | The pointer to the preprocess pass count is NULL. |
Remarks
During one-pass encoding (where the get_PreProcessPass method is 0), audio content is analyzed and compressed at the same time.
During two-pass encoding (where the get_PreProcessPass method is 1), audio content is analyzed in the first pass, and then the best combinations of bit rate, frame rate, buffer size, and image quality are applied during the second pass. Two-pass encoding produces a better-quality result but the process takes longer. To use two-pass encoding, the input cannot be a live source and the output cannot be a broadcast.
Requirements
Header: wmencode.h
Library: wmenc.exe
See Also
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