/* * $Id: test_w_saw.c,v 1.3 2003/03/02 08:01:47 dmazzoni Exp $ * test_w_saw.c * Generate stereo sawtooth waveforms. * * Author: Phil Burk, http://www.softsynth.com * * This program uses PABLIO, the Portable Audio Blocking I/O Library. * PABLIO is built on top of PortAudio, the Portable Audio Library. * * For more information see: http://www.audiomulch.com/portaudio/ * 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 <math.h>#include "pablio.h"#include <string.h>#define SAMPLE_RATE         (44100)#define NUM_SECONDS            (15)#define SAMPLES_PER_FRAME       (2)#define FREQUENCY           (220.0f)#define PHASE_INCREMENT     (2.0f * FREQUENCY / SAMPLE_RATE)#define FRAMES_PER_BLOCK    (100)float   samples[FRAMES_PER_BLOCK][SAMPLES_PER_FRAME];float   phases[SAMPLES_PER_FRAME];/*******************************************************************/int main(void);int main(void){    int             i,j;    PaError         err;    PABLIO_Stream  *aOutStream;    printf("Generate sawtooth waves using PABLIO.\n");    fflush(stdout);    /* Open simplified blocking I/O layer on top of PortAudio. */    err = OpenAudioStream( &aOutStream, SAMPLE_RATE, paFloat32,                           (PABLIO_WRITE | PABLIO_STEREO) );    if( err != paNoError ) goto error;    /* Initialize oscillator phases. */    phases[0] = 0.0;    phases[1] = 0.0;    for( i=0; i<(NUM_SECONDS * SAMPLE_RATE); i += FRAMES_PER_BLOCK )    {        /* Generate sawtooth waveforms in a block for efficiency. */        for( j=0; j<FRAMES_PER_BLOCK; j++ )        {            /* Generate a sawtooth wave by incrementing a variable. */            phases[0] += PHASE_INCREMENT;            /* The signal range is -1.0 to +1.0 so wrap around if we go over. */            if( phases[0] > 1.0f ) phases[0] -= 2.0f;            samples[j][0] = phases[0];            /* On the second channel, generate a sawtooth wave a fifth higher. */            phases[1] += PHASE_INCREMENT * (3.0f / 2.0f);            if( phases[1] > 1.0f ) phases[1] -= 2.0f;            samples[j][1] = phases[1];        }        /* Write samples to output. */        WriteAudioStream( aOutStream, samples, FRAMES_PER_BLOCK );    }    CloseAudioStream( aOutStream );    printf("Sawtooth sound test complete.\n" );    fflush(stdout);    return 0;error:    fprintf( stderr, "An error occured while using PABLIO\n" );    fprintf( stderr, "Error number: %d\n", err );    fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );    return -1;}