paex_write_sine.c

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00001 
00007 /*
00008  * $Id: paex_write_sine.c 1865 2012-09-01 21:16:25Z philburk $
00009  *
00010  * This program uses the PortAudio Portable Audio Library.
00011  * For more information see: http://www.portaudio.com/
00012  * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
00013  *
00014  * Permission is hereby granted, free of charge, to any person obtaining
00015  * a copy of this software and associated documentation files
00016  * (the "Software"), to deal in the Software without restriction,
00017  * including without limitation the rights to use, copy, modify, merge,
00018  * publish, distribute, sublicense, and/or sell copies of the Software,
00019  * and to permit persons to whom the Software is furnished to do so,
00020  * subject to the following conditions:
00021  *
00022  * The above copyright notice and this permission notice shall be
00023  * included in all copies or substantial portions of the Software.
00024  *
00025  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
00026  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00027  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
00028  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
00029  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
00030  * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
00031  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00032  */
00033 
00034 /*
00035  * The text above constitutes the entire PortAudio license; however, 
00036  * the PortAudio community also makes the following non-binding requests:
00037  *
00038  * Any person wishing to distribute modifications to the Software is
00039  * requested to send the modifications to the original developer so that
00040  * they can be incorporated into the canonical version. It is also 
00041  * requested that these non-binding requests be included along with the 
00042  * license above.
00043  */
00044 
00045 #include <stdio.h>
00046 #include <math.h>
00047 #include "portaudio.h"
00048 
00049 #define NUM_SECONDS         (5)
00050 #define SAMPLE_RATE         (44100)
00051 #define FRAMES_PER_BUFFER   (1024)
00052 
00053 #ifndef M_PI
00054 #define M_PI  (3.14159265)
00055 #endif
00056 
00057 #define TABLE_SIZE   (200)
00058 
00059 
00060 int main(void);
00061 int main(void)
00062 {
00063     PaStreamParameters outputParameters;
00064     PaStream *stream;
00065     PaError err;
00066     float buffer[FRAMES_PER_BUFFER][2]; /* stereo output buffer */
00067     float sine[TABLE_SIZE]; /* sine wavetable */
00068     int left_phase = 0;
00069     int right_phase = 0;
00070     int left_inc = 1;
00071     int right_inc = 3; /* higher pitch so we can distinguish left and right. */
00072     int i, j, k;
00073     int bufferCount;
00074     
00075     printf("PortAudio Test: output sine wave. SR = %d, BufSize = %d\n", SAMPLE_RATE, FRAMES_PER_BUFFER);
00076     
00077     /* initialise sinusoidal wavetable */
00078     for( i=0; i<TABLE_SIZE; i++ )
00079     {
00080         sine[i] = (float) sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. );
00081     }
00082 
00083     
00084     err = Pa_Initialize();
00085     if( err != paNoError ) goto error;
00086 
00087     outputParameters.device = Pa_GetDefaultOutputDevice(); /* default output device */
00088     if (outputParameters.device == paNoDevice) {
00089       fprintf(stderr,"Error: No default output device.\n");
00090       goto error;
00091     }
00092     outputParameters.channelCount = 2;       /* stereo output */
00093     outputParameters.sampleFormat = paFloat32; /* 32 bit floating point output */
00094     outputParameters.suggestedLatency = 0.050; // Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
00095     outputParameters.hostApiSpecificStreamInfo = NULL;
00096 
00097     err = Pa_OpenStream(
00098               &stream,
00099               NULL, /* no input */
00100               &outputParameters,
00101               SAMPLE_RATE,
00102               FRAMES_PER_BUFFER,
00103               paClipOff,      /* we won't output out of range samples so don't bother clipping them */
00104               NULL, /* no callback, use blocking API */
00105               NULL ); /* no callback, so no callback userData */
00106     if( err != paNoError ) goto error;
00107 
00108 
00109     printf( "Play 3 times, higher each time.\n" );
00110     
00111     for( k=0; k < 3; ++k )
00112     {
00113         err = Pa_StartStream( stream );
00114         if( err != paNoError ) goto error;
00115 
00116         printf("Play for %d seconds.\n", NUM_SECONDS );
00117 
00118         bufferCount = ((NUM_SECONDS * SAMPLE_RATE) / FRAMES_PER_BUFFER);
00119 
00120         for( i=0; i < bufferCount; i++ )
00121         {
00122             for( j=0; j < FRAMES_PER_BUFFER; j++ )
00123             {
00124                 buffer[j][0] = sine[left_phase];  /* left */
00125                 buffer[j][1] = sine[right_phase];  /* right */
00126                 left_phase += left_inc;
00127                 if( left_phase >= TABLE_SIZE ) left_phase -= TABLE_SIZE;
00128                 right_phase += right_inc;
00129                 if( right_phase >= TABLE_SIZE ) right_phase -= TABLE_SIZE;
00130             }
00131 
00132             err = Pa_WriteStream( stream, buffer, FRAMES_PER_BUFFER );
00133             if( err != paNoError ) goto error;
00134         }   
00135 
00136         err = Pa_StopStream( stream );
00137         if( err != paNoError ) goto error;
00138 
00139         ++left_inc;
00140         ++right_inc;
00141 
00142         Pa_Sleep( 1000 );
00143     }
00144 
00145     err = Pa_CloseStream( stream );
00146     if( err != paNoError ) goto error;
00147 
00148     Pa_Terminate();
00149     printf("Test finished.\n");
00150     
00151     return err;
00152 
00153 error:
00154     fprintf( stderr, "An error occured while using the portaudio stream\n" );
00155     fprintf( stderr, "Error number: %d\n", err );
00156     fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
00157         // Print more information about the error.
00158         if( err == paUnanticipatedHostError )
00159         {
00160                 const PaHostErrorInfo *hostErrorInfo = Pa_GetLastHostErrorInfo();
00161                 fprintf( stderr, "Host API error = #%ld, hostApiType = %d\n", hostErrorInfo->errorCode, hostErrorInfo->hostApiType );
00162                 fprintf( stderr, "Host API error = %s\n", hostErrorInfo->errorText );
00163         }
00164     Pa_Terminate();
00165     return err;
00166 }

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