/*
*	File:		ProcessFloatSamples.h
*
*	Contains:	This file provides the interface to a simple filter that implements a lowpass filter with with a 400 Hz cutoff.  
*				Good references for the implementation of filters include:
*				 -Discrete-Time Signal Processing, Schafer
*				 -Introduction to Signal Processing, Orfanidis
*				 -Understanding Digital Signal Processing, Lyons
*	
*	Version:	1.0
*
*	Created:	11-23-2004
*
*   � Copyright 2004-2013 Apple Computer, Inc. All rights reserved.
*
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#include <IOKit/IOTypes.h>

// _ParamStruct - coefficients for filter

__BEGIN_DECLS

typedef struct _ParamStruct 
{
	float		b0;
	float		b1;
	float		b2;
	float		a1;
	float		a2;
} ParamStruct, *ParamStructPtr;

// _StateStruct - state variables for filter

typedef struct _StateStruct 
{
	float		xstate1l;
	float		xstate2l;
	float		ystate1l;
	float		ystate2l;
	float		xstate1r;
	float		xstate2r;
	float		ystate1r;
	float		ystate2r;
} StateStruct, *StateStructPtr;

void processSamples (float * dataBuffer, UInt32 numSampleFrames, UInt32 numChannels, ParamStructPtr inParamStructPtr, StateStructPtr inStateStructPtr);
void resetProcessingState (StateStructPtr inStateStructPtr);
void setProcessingParameters (ParamStructPtr inParamStructPtr, UInt32 inSampleRate, UInt32 inNumChannels);

__END_DECLS