Returns the number of input frames required to generate the given number of output frames.
UINT32 CalcInputFrames( UINT32 OutputFrameCount );
The number of output frames desired.
Returns the number of input frames required.
XAudio2 calls this method to determine what size input buffer an XAPO requires to generate the given number of output frames. This method only needs to be called once while an XAPO is locked. CalcInputFrames is only called by XAudio2 if the XAPO is locked.
This function should not block, because it may be called from the realtime audio processing thread.