paex_sine.c (5999B)
1 /** @file paex_sine.c 2 @ingroup examples_src 3 @brief Play a sine wave for several seconds. 4 @author Ross Bencina <rossb@audiomulch.com> 5 @author Phil Burk <philburk@softsynth.com> 6 */ 7 /* 8 * $Id$ 9 * 10 * This program uses the PortAudio Portable Audio Library. 11 * For more information see: http://www.portaudio.com/ 12 * Copyright (c) 1999-2000 Ross Bencina and Phil Burk 13 * 14 * Permission is hereby granted, free of charge, to any person obtaining 15 * a copy of this software and associated documentation files 16 * (the "Software"), to deal in the Software without restriction, 17 * including without limitation the rights to use, copy, modify, merge, 18 * publish, distribute, sublicense, and/or sell copies of the Software, 19 * and to permit persons to whom the Software is furnished to do so, 20 * subject to the following conditions: 21 * 22 * The above copyright notice and this permission notice shall be 23 * included in all copies or substantial portions of the Software. 24 * 25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 28 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR 29 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF 30 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 31 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 32 */ 33 34 /* 35 * The text above constitutes the entire PortAudio license; however, 36 * the PortAudio community also makes the following non-binding requests: 37 * 38 * Any person wishing to distribute modifications to the Software is 39 * requested to send the modifications to the original developer so that 40 * they can be incorporated into the canonical version. It is also 41 * requested that these non-binding requests be included along with the 42 * license above. 43 */ 44 #include <stdio.h> 45 #include <math.h> 46 #include "portaudio.h" 47 48 #define NUM_SECONDS (5) 49 #define SAMPLE_RATE (44100) 50 #define FRAMES_PER_BUFFER (64) 51 52 #ifndef M_PI 53 #define M_PI (3.14159265) 54 #endif 55 56 #define TABLE_SIZE (200) 57 typedef struct 58 { 59 float sine[TABLE_SIZE]; 60 int left_phase; 61 int right_phase; 62 char message[20]; 63 } 64 paTestData; 65 66 /* This routine will be called by the PortAudio engine when audio is needed. 67 ** It may called at interrupt level on some machines so don't do anything 68 ** that could mess up the system like calling malloc() or free(). 69 */ 70 static int patestCallback( const void *inputBuffer, void *outputBuffer, 71 unsigned long framesPerBuffer, 72 const PaStreamCallbackTimeInfo* timeInfo, 73 PaStreamCallbackFlags statusFlags, 74 void *userData ) 75 { 76 paTestData *data = (paTestData*)userData; 77 float *out = (float*)outputBuffer; 78 unsigned long i; 79 80 (void) timeInfo; /* Prevent unused variable warnings. */ 81 (void) statusFlags; 82 (void) inputBuffer; 83 84 for( i=0; i<framesPerBuffer; i++ ) 85 { 86 *out++ = data->sine[data->left_phase]; /* left */ 87 *out++ = data->sine[data->right_phase]; /* right */ 88 data->left_phase += 1; 89 if( data->left_phase >= TABLE_SIZE ) data->left_phase -= TABLE_SIZE; 90 data->right_phase += 3; /* higher pitch so we can distinguish left and right. */ 91 if( data->right_phase >= TABLE_SIZE ) data->right_phase -= TABLE_SIZE; 92 } 93 94 return paContinue; 95 } 96 97 /* 98 * This routine is called by portaudio when playback is done. 99 */ 100 static void StreamFinished( void* userData ) 101 { 102 paTestData *data = (paTestData *) userData; 103 printf( "Stream Completed: %s\n", data->message ); 104 } 105 106 /*******************************************************************/ 107 int main(void); 108 int main(void) 109 { 110 PaStreamParameters outputParameters; 111 PaStream *stream; 112 PaError err; 113 paTestData data; 114 int i; 115 116 printf("PortAudio Test: output sine wave. SR = %d, BufSize = %d\n", SAMPLE_RATE, FRAMES_PER_BUFFER); 117 118 /* initialise sinusoidal wavetable */ 119 for( i=0; i<TABLE_SIZE; i++ ) 120 { 121 data.sine[i] = (float) sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. ); 122 } 123 data.left_phase = data.right_phase = 0; 124 125 err = Pa_Initialize(); 126 if( err != paNoError ) goto error; 127 128 outputParameters.device = Pa_GetDefaultOutputDevice(); /* default output device */ 129 if (outputParameters.device == paNoDevice) { 130 fprintf(stderr,"Error: No default output device.\n"); 131 goto error; 132 } 133 outputParameters.channelCount = 2; /* stereo output */ 134 outputParameters.sampleFormat = paFloat32; /* 32 bit floating point output */ 135 outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency; 136 outputParameters.hostApiSpecificStreamInfo = NULL; 137 138 err = Pa_OpenStream( 139 &stream, 140 NULL, /* no input */ 141 &outputParameters, 142 SAMPLE_RATE, 143 FRAMES_PER_BUFFER, 144 paClipOff, /* we won't output out of range samples so don't bother clipping them */ 145 patestCallback, 146 &data ); 147 if( err != paNoError ) goto error; 148 149 sprintf( data.message, "No Message" ); 150 err = Pa_SetStreamFinishedCallback( stream, &StreamFinished ); 151 if( err != paNoError ) goto error; 152 153 err = Pa_StartStream( stream ); 154 if( err != paNoError ) goto error; 155 156 printf("Play for %d seconds.\n", NUM_SECONDS ); 157 Pa_Sleep( NUM_SECONDS * 1000 ); 158 159 err = Pa_StopStream( stream ); 160 if( err != paNoError ) goto error; 161 162 err = Pa_CloseStream( stream ); 163 if( err != paNoError ) goto error; 164 165 Pa_Terminate(); 166 printf("Test finished.\n"); 167 168 return err; 169 error: 170 Pa_Terminate(); 171 fprintf( stderr, "An error occured while using the portaudio stream\n" ); 172 fprintf( stderr, "Error number: %d\n", err ); 173 fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) ); 174 return err; 175 }