Sub BufferLinesMix( _
   ByVal _bsLineFrom As String, _
   ByVal _bsLineTo As String, _
   ByRef _plSamplesMix As Integer, _
   ByVal _dblGainFromStartDb As Double, _
   ByVal _dblGainFromEndDb As Double, _
   ByVal _dblGainToStartDb As Double, _
   ByVal _dblGainToEndDb As Double, _
   ByVal _bsChannelsListIn As String, _
   ByVal _bsChannelsListOut As String _
) 

void BufferLinesMix( 
   string _bsLineFrom,
   string _bsLineTo,
   out int _plSamplesMix,
   double _dblGainFromStartDb,
   double _dblGainFromEndDb,
   double _dblGainToStartDb,
   double _dblGainToEndDb,
   string _bsChannelsListIn,
   string _bsChannelsListOut
)

procedure BufferLinesMix( 
    _bsLineFrom: String;
    _bsLineTo: String;
   Out  _plSamplesMix: Integer;
    _dblGainFromStartDb: Double;
    _dblGainFromEndDb: Double;
    _dblGainToStartDb: Double;
    _dblGainToEndDb: Double;
    _bsChannelsListIn: String;
    _bsChannelsListOut: String
); 

void BufferLinesMix( 
   BSTR* _bsLineFrom,
   BSTR* _bsLineTo,
   [PARAMFLAG::Out] int _plSamplesMix,
   double _dblGainFromStartDb,
   double _dblGainFromEndDb,
   double _dblGainToStartDb,
   double _dblGainToEndDb,
   BSTR* _bsChannelsListIn,
   BSTR* _bsChannelsListOut
) 

Parameters

_bsLineFrom

line from which audio is mixed

_bsLineTo

line to which audio is mixed

_plSamplesMix

mixed samples

_dblGainFromStartDb

start gain in dB for "from" line

_dblGainFromEndDb

end gain in dB for "from" line

_dblGainToStartDb

start gain in dB for "to" line

_dblGainToEndDb

end gain in dB for "to" line

_bsChannelsListIn

list of input audio channels, for example "0,1,2,3"

_bsChannelsListOut

list of output audio channels, for example "0,3,2,1"

Reference

IMFAudioBuffer Interface
IMFAudioBuffer Members