mirror of
https://github.com/cookiengineer/audacity
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113 lines
3.9 KiB
C
113 lines
3.9 KiB
C
/*
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* $Id: test_w_saw8.c 1083 2006-08-23 07:30:49Z rossb $
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* test_w_saw8.c
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* Generate stereo 8 bit sawtooth waveforms.
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*
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* Author: Phil Burk, http://www.softsynth.com
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*
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* This program uses PABLIO, the Portable Audio Blocking I/O Library.
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* PABLIO is built on top of PortAudio, the Portable Audio Library.
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*
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* For more information see: http://www.portaudio.com
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* Copyright (c) 1999-2000 Ross Bencina and Phil Burk
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*
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files
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* (the "Software"), to deal in the Software without restriction,
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* including without limitation the rights to use, copy, modify, merge,
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* publish, distribute, sublicense, and/or sell copies of the Software,
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* and to permit persons to whom the Software is furnished to do so,
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* subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
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* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
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* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
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* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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/*
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* The text above constitutes the entire PortAudio license; however,
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* the PortAudio community also makes the following non-binding requests:
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*
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* Any person wishing to distribute modifications to the Software is
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* requested to send the modifications to the original developer so that
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* they can be incorporated into the canonical version. It is also
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* requested that these non-binding requests be included along with the
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* license above.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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#include "pablio.h"
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#include <string.h>
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#define SAMPLE_RATE (22050)
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#define NUM_SECONDS (6)
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#define SAMPLES_PER_FRAME (2)
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#define FRAMES_PER_BLOCK (100)
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unsigned char samples[FRAMES_PER_BLOCK][SAMPLES_PER_FRAME];
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unsigned char phases[SAMPLES_PER_FRAME];
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/*******************************************************************/
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int main(void);
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int main(void)
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{
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int i,j;
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PaError err;
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PABLIO_Stream *aOutStream;
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printf("Generate unsigned 8 bit sawtooth waves using PABLIO.\n");
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fflush(stdout);
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/* Open simplified blocking I/O layer on top of PortAudio. */
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err = OpenAudioStream( &aOutStream, SAMPLE_RATE, paUInt8,
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(PABLIO_WRITE | PABLIO_STEREO) );
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if( err != paNoError ) goto error;
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/* Initialize oscillator phases to "ground" level for paUInt8. */
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phases[0] = 128;
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phases[1] = 128;
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for( i=0; i<(NUM_SECONDS * SAMPLE_RATE); i += FRAMES_PER_BLOCK )
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{
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/* Generate sawtooth waveforms in a block for efficiency. */
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for( j=0; j<FRAMES_PER_BLOCK; j++ )
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{
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/* Generate a sawtooth wave by incrementing a variable. */
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phases[0] += 1;
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/* We don't have to do anything special to wrap when using paUint8 because
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* 8 bit arithmetic automatically wraps. */
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samples[j][0] = phases[0];
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/* On the second channel, generate a higher sawtooth wave. */
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phases[1] += 3;
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samples[j][1] = phases[1];
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}
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/* Write samples to output. */
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WriteAudioStream( aOutStream, samples, FRAMES_PER_BLOCK );
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}
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CloseAudioStream( aOutStream );
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printf("Sawtooth sound test complete.\n" );
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fflush(stdout);
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return 0;
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error:
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fprintf( stderr, "An error occured while using PABLIO\n" );
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fprintf( stderr, "Error number: %d\n", err );
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fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
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return -1;
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}
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