patest_record.c

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/*
 * $Id: patest_record.c,v 1.3 2003/03/02 08:01:42 dmazzoni Exp $
 * patest_record.c
 * Record input into an array.
 * Save array to a file.
 * Playback recorded data.
 *
 * Author: Phil Burk  http://www.softsynth.com
 *
 * This program uses the PortAudio Portable Audio Library.
 * For more information see: http://www.portaudio.com
 * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
 *
 * 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.
 *
 * 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.
 *
 * 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.
 *
 */
#include <stdio.h>
#include <stdlib.h>
#include "portaudio.h"

/* #define SAMPLE_RATE  (17932) /* Test failure to open with this value. */
#define SAMPLE_RATE  (22050)
#define NUM_SECONDS     (5)
#define NUM_CHANNELS    (2)
/* #define DITHER_FLAG     (paDitherOff)  /**/
#define DITHER_FLAG     (0) /**/
#define FRAMES_PER_BUFFER  (1024)

/* Select sample format. */
#if 1
#define PA_SAMPLE_TYPE  paFloat32
typedef float SAMPLE;
#define SAMPLE_SILENCE  (0.0f)
#elif 0
#define PA_SAMPLE_TYPE  paInt16
typedef short SAMPLE;
#define SAMPLE_SILENCE  (0)
#elif 0
#define PA_SAMPLE_TYPE  paInt8
typedef char SAMPLE;
#define SAMPLE_SILENCE  (0)
#else
#define PA_SAMPLE_TYPE  paUInt8
typedef unsigned char SAMPLE;
#define SAMPLE_SILENCE  (128)

#endif

typedef struct
{
    int          frameIndex;  /* Index into sample array. */
    int          maxFrameIndex;
    SAMPLE      *recordedSamples;
}
paTestData;
/* This routine will be called by the PortAudio engine when audio is needed.
** It may be called at interrupt level on some machines so don't do anything
** that could mess up the system like calling malloc() or free().
*/
static int recordCallback( void *inputBuffer, void *outputBuffer,
                           unsigned long framesPerBuffer,
                           PaTimestamp outTime, void *userData )
{
    paTestData *data = (paTestData*)userData;
    SAMPLE *rptr = (SAMPLE*)inputBuffer;
    SAMPLE *wptr = &data->recordedSamples[data->frameIndex * NUM_CHANNELS];
    long framesToCalc;
    long i;
    int finished;
    unsigned long framesLeft = data->maxFrameIndex - data->frameIndex;

    (void) outputBuffer; /* Prevent unused variable warnings. */
    (void) outTime;

    if( framesLeft < framesPerBuffer )
    {
        framesToCalc = framesLeft;
        finished = 1;
    }
    else
    {
        framesToCalc = framesPerBuffer;
        finished = 0;
    }
    if( inputBuffer == NULL )
    {
        for( i=0; i<framesToCalc; i++ )
        {
            *wptr++ = SAMPLE_SILENCE;  /* left */
            if( NUM_CHANNELS == 2 ) *wptr++ = SAMPLE_SILENCE;  /* right */
        }
    }
    else
    {
        for( i=0; i<framesToCalc; i++ )
        {
            *wptr++ = *rptr++;  /* left */
            if( NUM_CHANNELS == 2 ) *wptr++ = *rptr++;  /* right */
        }
    }
    data->frameIndex += framesToCalc;
    return finished;
}

/* This routine will be called by the PortAudio engine when audio is needed.
** It may be called at interrupt level on some machines so don't do anything
** that could mess up the system like calling malloc() or free().
*/
static int playCallback( void *inputBuffer, void *outputBuffer,
                         unsigned long framesPerBuffer,
                         PaTimestamp outTime, void *userData )
{
    paTestData *data = (paTestData*)userData;
    SAMPLE *rptr = &data->recordedSamples[data->frameIndex * NUM_CHANNELS];
    SAMPLE *wptr = (SAMPLE*)outputBuffer;
    unsigned int i;
    int finished;
    unsigned int framesLeft = data->maxFrameIndex - data->frameIndex;
    (void) inputBuffer; /* Prevent unused variable warnings. */
    (void) outTime;

    if( framesLeft < framesPerBuffer )
    {
        /* final buffer... */
        for( i=0; i<framesLeft; i++ )
        {
            *wptr++ = *rptr++;  /* left */
            if( NUM_CHANNELS == 2 ) *wptr++ = *rptr++;  /* right */
        }
        for( ; i<framesPerBuffer; i++ )
        {
            *wptr++ = 0;  /* left */
            if( NUM_CHANNELS == 2 ) *wptr++ = 0;  /* right */
        }
        data->frameIndex += framesLeft;
        finished = 1;
    }
    else
    {
        for( i=0; i<framesPerBuffer; i++ )
        {
            *wptr++ = *rptr++;  /* left */
            if( NUM_CHANNELS == 2 ) *wptr++ = *rptr++;  /* right */
        }
        data->frameIndex += framesPerBuffer;
        finished = 0;
    }
    return finished;
}

/*******************************************************************/
int main(void);
int main(void)
{
    PortAudioStream *stream;
    PaError    err;
    paTestData data;
    int        i;
    int        totalFrames;
    int        numSamples;
    int        numBytes;
    SAMPLE     max, average, val;
    printf("patest_record.c\n"); fflush(stdout);

    data.maxFrameIndex = totalFrames = NUM_SECONDS * SAMPLE_RATE; /* Record for a few seconds. */
    data.frameIndex = 0;
    numSamples = totalFrames * NUM_CHANNELS;

    numBytes = numSamples * sizeof(SAMPLE);
    data.recordedSamples = (SAMPLE *) malloc( numBytes );
    if( data.recordedSamples == NULL )
    {
        printf("Could not allocate record array.\n");
        exit(1);
    }
    for( i=0; i<numSamples; i++ ) data.recordedSamples[i] = 0;

    err = Pa_Initialize();
    if( err != paNoError ) goto error;

    /* Record some audio. -------------------------------------------- */
    err = Pa_OpenStream(
              &stream,
              Pa_GetDefaultInputDeviceID(),
              NUM_CHANNELS,               /* stereo input */
              PA_SAMPLE_TYPE,
              NULL,
              paNoDevice,
              0,
              PA_SAMPLE_TYPE,
              NULL,
              SAMPLE_RATE,
              FRAMES_PER_BUFFER,            /* frames per buffer */
              0,               /* number of buffers, if zero then use default minimum */
              0, //paDitherOff,    /* flags */
              recordCallback,
              &data );
    if( err != paNoError ) goto error;

    err = Pa_StartStream( stream );
    if( err != paNoError ) goto error;
    printf("Now recording!!\n"); fflush(stdout);

    while( Pa_StreamActive( stream ) )
    {
        Pa_Sleep(1000);
        printf("index = %d\n", data.frameIndex ); fflush(stdout);
    }

    err = Pa_CloseStream( stream );
    if( err != paNoError ) goto error;

    /* Measure maximum peak amplitude. */
    max = 0;
    average = 0;
    for( i=0; i<numSamples; i++ )
    {
        val = data.recordedSamples[i];
        if( val < 0 ) val = -val; /* ABS */
        if( val > max )
        {
            max = val;
        }
        average += val;
    }
    
    average = average / numSamples;

    if( PA_SAMPLE_TYPE == paFloat32 )
    {
        printf("sample max amplitude = %f\n", max );
        printf("sample average = %f\n", average );
    }
    else
    {
        printf("sample max amplitude = %d\n", max );
        printf("sample average = %d\n", average );
    }
    
    /* Write recorded data to a file. */
#if 0
    {
        FILE  *fid;
        fid = fopen("recorded.raw", "wb");
        if( fid == NULL )
        {
            printf("Could not open file.");
        }
        else
        {
            fwrite( data.recordedSamples, NUM_CHANNELS * sizeof(SAMPLE), totalFrames, fid );
            fclose( fid );
            printf("Wrote data to 'recorded.raw'\n");
        }
    }
#endif

    /* Playback recorded data.  -------------------------------------------- */
    data.frameIndex = 0;
    printf("Begin playback.\n"); fflush(stdout);
    err = Pa_OpenStream(
              &stream,
              paNoDevice,
              0,               /* NO input */
              PA_SAMPLE_TYPE,
              NULL,
              Pa_GetDefaultOutputDeviceID(),
              NUM_CHANNELS,               /* stereo output */
              PA_SAMPLE_TYPE,
              NULL,
              SAMPLE_RATE,
              FRAMES_PER_BUFFER,            /* frames per buffer */
              0,               /* number of buffers, if zero then use default minimum */
              paClipOff,       /* we won't output out of range samples so don't bother clipping them */
              playCallback,
              &data );
    if( err != paNoError ) goto error;

    if( stream )
    {
        err = Pa_StartStream( stream );
        if( err != paNoError ) goto error;
        printf("Waiting for playback to finish.\n"); fflush(stdout);

        while( Pa_StreamActive( stream ) ) Pa_Sleep(100);

        err = Pa_CloseStream( stream );
        if( err != paNoError ) goto error;
        printf("Done.\n"); fflush(stdout);
    }
    free( data.recordedSamples );

    Pa_Terminate();
    return 0;

error:
    Pa_Terminate();
    fprintf( stderr, "An error occured while using the portaudio stream\n" );
    fprintf( stderr, "Error number: %d\n", err );
    fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
    return -1;
}