/* * $Id: debug_sine_amp.c,v 1.1.1.1 2003-05-09 16:03:56 ggeiger Exp $ * Play a different sine wave on each channels, * using the Portable Audio api. * Allos amplitude to be set interactively. * * Author: Phil Burk http://www.softsynth.com * * This program uses the PortAudio Portable Audio Library. * For more information see: http://www.portaudio.com * 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 #include #include "portaudio.h" #define OUTPUT_DEVICE (Pa_GetDefaultOutputDeviceID()) #define SAMPLE_RATE (44100) #define FRAMES_PER_BUFFER (256) #define FREQ_INCR (300.0 / SAMPLE_RATE) #define MAX_CHANNELS (64) #ifndef M_PI #define M_PI (3.14159265) #endif typedef struct { int numChannels; double phases[MAX_CHANNELS]; float amplitude; } paTestData; /* This routine will be called by the PortAudio engine when audio is needed. ** It may called at interrupt level on some machines so don't do anything ** that could mess up the system like calling malloc() or free(). */ static int patestCallback( void *inputBuffer, void *outputBuffer, unsigned long framesPerBuffer, PaTimestamp outTime, void *userData ) { paTestData *data = (paTestData*)userData; float *out = (float*)outputBuffer; int frameIndex, channelIndex; (void) outTime; /* Prevent unused variable warnings. */ (void) inputBuffer; for( frameIndex=0; frameIndex<(int)framesPerBuffer; frameIndex++ ) { for( channelIndex=0; channelIndexnumChannels; channelIndex++ ) { /* Output sine wave on every channel. */ *out++ = (float) ( data->amplitude * sin(data->phases[channelIndex]) ); /* Play each channel at a higher frequency. */ data->phases[channelIndex] += FREQ_INCR * (4 + channelIndex); if( data->phases[channelIndex] >= (2.0 * M_PI) ) data->phases[channelIndex] -= (2.0 * M_PI); } } return 0; } /*******************************************************************/ int main(void); int main(void) { char pad[256]; PortAudioStream *stream; PaError err; const PaDeviceInfo *pdi; paTestData data = {0}; printf("PortAudio Test: output sine wave on each channel.\n" ); err = Pa_Initialize(); if( err != paNoError ) goto error; pdi = Pa_GetDeviceInfo( OUTPUT_DEVICE ); data.numChannels = pdi->maxOutputChannels; if( data.numChannels > MAX_CHANNELS ) data.numChannels = MAX_CHANNELS; printf("Number of Channels = %d\n", data.numChannels ); data.amplitude = 1.0; err = Pa_OpenStream( &stream, paNoDevice, /* default input device */ 0, /* no input */ paFloat32, /* 32 bit floating point input */ NULL, OUTPUT_DEVICE, data.numChannels, paFloat32, /* 32 bit floating point output */ NULL, SAMPLE_RATE, FRAMES_PER_BUFFER, /* frames per buffer */ 0, /* number of buffers, if zero then use default minimum */ paClipOff, /* we won't output out of range samples so don't bother clipping them */ patestCallback, &data ); if( err != paNoError ) goto error; err = Pa_StartStream( stream ); if( err != paNoError ) goto error; do { printf("Current amplitude = %f\n", data.amplitude ); printf("Enter new amplitude or 'q' to quit.\n"); fflush(stdout); gets( pad ); if( pad[0] != 'q' ) { // I tried to use atof but it seems to be broken on Mac OS X 10.1 float amp; sscanf( pad, "%f", & ); data.amplitude = amp; } } while( pad[0] != 'q' ); err = Pa_StopStream( stream ); if( err != paNoError ) goto error; Pa_CloseStream( stream ); Pa_Terminate(); printf("Test finished.\n"); return err; error: Pa_Terminate(); fprintf( stderr, "An error occured while using the portaudio stream\n" ); fprintf( stderr, "Error number: %d\n", err ); fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) ); return err; }