audio_analyzer.h

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/*
 * PortAudio Portable Real-Time Audio Library
 * Latest Version at: http://www.portaudio.com
 *
 * Copyright (c) 1999-2010 Phil Burk and Ross Bencina
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * The text above constitutes the entire PortAudio license; however, 
 * the PortAudio community also makes the following non-binding requests:
 *
 * Any person wishing to distribute modifications to the Software is
 * requested to send the modifications to the original developer so that
 * they can be incorporated into the canonical version. It is also 
 * requested that these non-binding requests be included along with the 
 * license above.
 */

#ifndef _AUDIO_ANALYZER_H
#define _AUDIO_ANALYZER_H

#include "biquad_filter.h"

#define MATH_PI  (3.141592653589793238462643)
#define MATH_TWO_PI  (2.0 * MATH_PI)

typedef struct PaQaSineGenerator_s
{
        double    phase;
        double    phaseIncrement;
        double    frequency;
        double    amplitude;
} PaQaSineGenerator;

typedef struct PaQaRecording_s
{
        int       maxFrames;
        float    *buffer;
        int       numFrames;
        int       sampleRate;
} PaQaRecording;

typedef struct PaQaTestTone_s
{
        int       samplesPerFrame;
        int       startDelay;
        double    sampleRate;
        double    frequency;
        double    amplitude;
} PaQaTestTone;

typedef struct PaQaAnalysisResult_s
{
        int       valid;
        double    latency;
        double    amplitudeRatio;
        double    popAmplitude;
        double    popPosition;
        double    numDroppedFrames;
        double    droppedFramesPosition;
        double    numAddedFrames;
        double    addedFramesPosition;
} PaQaAnalysisResult;


/*================================================================*/
/*================= General DSP Tools ============================*/
/*================================================================*/
double PaQa_GetNthFrequency( double baseFrequency, int index );

void PaQa_EraseBuffer( float *buffer, int numFrames, int samplesPerFrame );

void PaQa_MixSine( PaQaSineGenerator *generator, float *buffer, int numSamples, int stride );

void PaQa_WriteSine( float *buffer, int numSamples, int stride,
                                        double frequency, double amplitude );

void PaQa_GenerateCrack( float *buffer, int numSamples, int stride );

double PaQa_ComputePhaseDifference( double phase1, double phase2 );

double PaQa_MeasureArea( float *buffer, int numFrames, int stride  );

double PaQa_MeasureCrossingSlope( float *buffer, int numFrames );


void PaQa_SetupSineGenerator( PaQaSineGenerator *generator, double frequency, double amplitude, double frameRate );

/*================================================================*/
/*================= Recordings ===================================*/
/*================================================================*/
 int PaQa_InitializeRecording( PaQaRecording *recording, int maxSamples, int sampleRate );
 
 void PaQa_TerminateRecording( PaQaRecording *recording );
 
void PaQa_FilterRecording( PaQaRecording *input, PaQaRecording *output, BiquadFilter *filter );


int PaQa_SaveRecordingToWaveFile( PaQaRecording *recording, const char *filename );
 
int PaQa_WriteRecording( PaQaRecording *recording, float *buffer, int numSamples, int stride );
 
int PaQa_WriteSilence( PaQaRecording *recording, int numSamples );
 
int PaQa_RecordFreeze( PaQaRecording *recording, int numSamples );

double PaQa_CorrelateSine( PaQaRecording *recording, double frequency, double frameRate,
                                                  int startFrame, int numSamples, double *phasePtr );

double PaQa_FindFirstMatch( PaQaRecording *recording, float *buffer, int numSamples, double tolerance  );

double PaQa_MeasureSineAmplitudeBySlope( PaQaRecording *recording,
                                                                                double frequency, double frameRate,
                                                                                int startFrame, int numFrames );

double PaQa_MeasureRootMeanSquare( float *buffer, int numFrames );

double PaQa_CompareAmplitudes( PaQaRecording *recording, int startAt, float *buffer, int numSamples );

int PaQa_AnalyseRecording( PaQaRecording *recording, PaQaTestTone *testTone, PaQaAnalysisResult *analysisResult );

#endif /* _AUDIO_ANALYZER_H */