/* * $Id: test_w_saw8.c,v 1.3 2003/03/02 08:01:47 dmazzoni Exp $ * test_w_saw8.c * Generate stereo 8 bit 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         (22050)#define NUM_SECONDS             (6)#define SAMPLES_PER_FRAME       (2)#define FRAMES_PER_BLOCK    (100)unsigned char   samples[FRAMES_PER_BLOCK][SAMPLES_PER_FRAME];unsigned char   phases[SAMPLES_PER_FRAME];/*******************************************************************/int main(void);int main(void){    int             i,j;    PaError         err;    PABLIO_Stream  *aOutStream;    printf("Generate unsigned 8 bit sawtooth waves using PABLIO.\n");    fflush(stdout);    /* Open simplified blocking I/O layer on top of PortAudio. */    err = OpenAudioStream( &aOutStream, SAMPLE_RATE, paUInt8,                           (PABLIO_WRITE | PABLIO_STEREO) );    if( err != paNoError ) goto error;    /* Initialize oscillator phases to "ground" level for paUInt8. */    phases[0] = 128;    phases[1] = 128;    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] += 1;            /* We don't have to do anything special to wrap when using paUint8 because             * 8 bit arithmetic automatically wraps. */            samples[j][0] = phases[0];            /* On the second channel, generate a higher sawtooth wave. */            phases[1] += 3;            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;}