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/*
* $Id$
* 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.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.
*
* 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.
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "pablio.h"
#include <string.h>
#define SAMPLE_RATE (44100)
#define NUM_SECONDS (6)
#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 occurred while using PABLIO\n" );
fprintf( stderr, "Error number: %d\n", err );
fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
return -1;
}
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