/* * $Id: test_w_saw8.c,v 1.1.1.1 2002/01/22 00:52:55 phil 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; }