Chris@4: /*
Chris@4:  * $Id: test_w_saw.c 1083 2006-08-23 07:30:49Z rossb $
Chris@4:  * test_w_saw.c
Chris@4:  * Generate stereo sawtooth waveforms.
Chris@4:  *
Chris@4:  * Author: Phil Burk, http://www.softsynth.com
Chris@4:  *
Chris@4:  * This program uses PABLIO, the Portable Audio Blocking I/O Library.
Chris@4:  * PABLIO is built on top of PortAudio, the Portable Audio Library.
Chris@4:  *
Chris@4:  * For more information see: http://www.portaudio.com
Chris@4:  * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
Chris@4:  *
Chris@4:  * Permission is hereby granted, free of charge, to any person obtaining
Chris@4:  * a copy of this software and associated documentation files
Chris@4:  * (the "Software"), to deal in the Software without restriction,
Chris@4:  * including without limitation the rights to use, copy, modify, merge,
Chris@4:  * publish, distribute, sublicense, and/or sell copies of the Software,
Chris@4:  * and to permit persons to whom the Software is furnished to do so,
Chris@4:  * subject to the following conditions:
Chris@4:  *
Chris@4:  * The above copyright notice and this permission notice shall be
Chris@4:  * included in all copies or substantial portions of the Software.
Chris@4:  *
Chris@4:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
Chris@4:  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
Chris@4:  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
Chris@4:  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
Chris@4:  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
Chris@4:  * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
Chris@4:  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Chris@4:  */
Chris@4: 
Chris@4: /*
Chris@4:  * The text above constitutes the entire PortAudio license; however, 
Chris@4:  * the PortAudio community also makes the following non-binding requests:
Chris@4:  *
Chris@4:  * Any person wishing to distribute modifications to the Software is
Chris@4:  * requested to send the modifications to the original developer so that
Chris@4:  * they can be incorporated into the canonical version. It is also 
Chris@4:  * requested that these non-binding requests be included along with the 
Chris@4:  * license above.
Chris@4:  */
Chris@4: 
Chris@4: #include <stdio.h>
Chris@4: #include <stdlib.h>
Chris@4: #include <math.h>
Chris@4: #include "pablio.h"
Chris@4: #include <string.h>
Chris@4: 
Chris@4: #define SAMPLE_RATE         (44100)
Chris@4: #define NUM_SECONDS             (6)
Chris@4: #define SAMPLES_PER_FRAME       (2)
Chris@4: 
Chris@4: #define FREQUENCY           (220.0f)
Chris@4: #define PHASE_INCREMENT     (2.0f * FREQUENCY / SAMPLE_RATE)
Chris@4: #define FRAMES_PER_BLOCK    (100)
Chris@4: 
Chris@4: float   samples[FRAMES_PER_BLOCK][SAMPLES_PER_FRAME];
Chris@4: float   phases[SAMPLES_PER_FRAME];
Chris@4: 
Chris@4: /*******************************************************************/
Chris@4: int main(void);
Chris@4: int main(void)
Chris@4: {
Chris@4:     int             i,j;
Chris@4:     PaError         err;
Chris@4:     PABLIO_Stream  *aOutStream;
Chris@4: 
Chris@4:     printf("Generate sawtooth waves using PABLIO.\n");
Chris@4:     fflush(stdout);
Chris@4: 
Chris@4:     /* Open simplified blocking I/O layer on top of PortAudio. */
Chris@4:     err = OpenAudioStream( &aOutStream, SAMPLE_RATE, paFloat32,
Chris@4:                            (PABLIO_WRITE | PABLIO_STEREO) );
Chris@4:     if( err != paNoError ) goto error;
Chris@4: 
Chris@4:     /* Initialize oscillator phases. */
Chris@4:     phases[0] = 0.0;
Chris@4:     phases[1] = 0.0;
Chris@4: 
Chris@4:     for( i=0; i<(NUM_SECONDS * SAMPLE_RATE); i += FRAMES_PER_BLOCK )
Chris@4:     {
Chris@4:         /* Generate sawtooth waveforms in a block for efficiency. */
Chris@4:         for( j=0; j<FRAMES_PER_BLOCK; j++ )
Chris@4:         {
Chris@4:             /* Generate a sawtooth wave by incrementing a variable. */
Chris@4:             phases[0] += PHASE_INCREMENT;
Chris@4:             /* The signal range is -1.0 to +1.0 so wrap around if we go over. */
Chris@4:             if( phases[0] > 1.0f ) phases[0] -= 2.0f;
Chris@4:             samples[j][0] = phases[0];
Chris@4: 
Chris@4:             /* On the second channel, generate a sawtooth wave a fifth higher. */
Chris@4:             phases[1] += PHASE_INCREMENT * (3.0f / 2.0f);
Chris@4:             if( phases[1] > 1.0f ) phases[1] -= 2.0f;
Chris@4:             samples[j][1] = phases[1];
Chris@4:         }
Chris@4: 
Chris@4:         /* Write samples to output. */
Chris@4:         WriteAudioStream( aOutStream, samples, FRAMES_PER_BLOCK );
Chris@4:     }
Chris@4: 
Chris@4:     CloseAudioStream( aOutStream );
Chris@4: 
Chris@4:     printf("Sawtooth sound test complete.\n" );
Chris@4:     fflush(stdout);
Chris@4:     return 0;
Chris@4: 
Chris@4: error:
Chris@4:     fprintf( stderr, "An error occured while using PABLIO\n" );
Chris@4:     fprintf( stderr, "Error number: %d\n", err );
Chris@4:     fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
Chris@4:     return -1;
Chris@4: }