cannam@89: /** @file patest_leftright.c cannam@89: @ingroup test_src cannam@89: @brief Play different tone sine waves that cannam@89: alternate between left and right channel. cannam@89: cannam@89: The low tone should be on the left channel. cannam@89: cannam@89: @author Ross Bencina cannam@89: @author Phil Burk cannam@89: */ cannam@89: /* cannam@89: * $Id: patest_leftright.c 1609 2011-02-27 00:06:07Z philburk $ cannam@89: * cannam@89: * This program uses the PortAudio Portable Audio Library. cannam@89: * For more information see: http://www.portaudio.com cannam@89: * Copyright (c) 1999-2000 Ross Bencina and Phil Burk cannam@89: * cannam@89: * Permission is hereby granted, free of charge, to any person obtaining cannam@89: * a copy of this software and associated documentation files cannam@89: * (the "Software"), to deal in the Software without restriction, cannam@89: * including without limitation the rights to use, copy, modify, merge, cannam@89: * publish, distribute, sublicense, and/or sell copies of the Software, cannam@89: * and to permit persons to whom the Software is furnished to do so, cannam@89: * subject to the following conditions: cannam@89: * cannam@89: * The above copyright notice and this permission notice shall be cannam@89: * included in all copies or substantial portions of the Software. cannam@89: * cannam@89: * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, cannam@89: * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF cannam@89: * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. cannam@89: * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR cannam@89: * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF cannam@89: * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION cannam@89: * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. cannam@89: */ cannam@89: cannam@89: /* cannam@89: * The text above constitutes the entire PortAudio license; however, cannam@89: * the PortAudio community also makes the following non-binding requests: cannam@89: * cannam@89: * Any person wishing to distribute modifications to the Software is cannam@89: * requested to send the modifications to the original developer so that cannam@89: * they can be incorporated into the canonical version. It is also cannam@89: * requested that these non-binding requests be included along with the cannam@89: * license above. cannam@89: */ cannam@89: cannam@89: #include cannam@89: #include cannam@89: #include "portaudio.h" cannam@89: cannam@89: #define NUM_SECONDS (8) cannam@89: #define SAMPLE_RATE (44100) cannam@89: #define FRAMES_PER_BUFFER (512) cannam@89: #ifndef M_PI cannam@89: #define M_PI (3.14159265) cannam@89: #endif cannam@89: #define TABLE_SIZE (200) cannam@89: #define BALANCE_DELTA (0.001) cannam@89: cannam@89: typedef struct cannam@89: { cannam@89: float sine[TABLE_SIZE]; cannam@89: int left_phase; cannam@89: int right_phase; cannam@89: float targetBalance; // 0.0 = left, 1.0 = right cannam@89: float currentBalance; cannam@89: } paTestData; cannam@89: cannam@89: /* This routine will be called by the PortAudio engine when audio is needed. cannam@89: ** It may called at interrupt level on some machines so don't do anything cannam@89: ** that could mess up the system like calling malloc() or free(). cannam@89: */ cannam@89: static int patestCallback( const void *inputBuffer, cannam@89: void *outputBuffer, cannam@89: unsigned long framesPerBuffer, cannam@89: const PaStreamCallbackTimeInfo* timeInfo, cannam@89: PaStreamCallbackFlags statusFlags, cannam@89: void *userData ) cannam@89: { cannam@89: paTestData *data = (paTestData*)userData; cannam@89: float *out = (float*)outputBuffer; cannam@89: unsigned long i; cannam@89: int finished = 0; cannam@89: /* Prevent unused variable warnings. */ cannam@89: (void) inputBuffer; cannam@89: cannam@89: for( i=0; icurrentBalance < data->targetBalance ) cannam@89: { cannam@89: data->currentBalance += BALANCE_DELTA; cannam@89: } cannam@89: else if( data->currentBalance > data->targetBalance ) cannam@89: { cannam@89: data->currentBalance -= BALANCE_DELTA; cannam@89: } cannam@89: // Apply left/right balance. cannam@89: *out++ = data->sine[data->left_phase] * (1.0f - data->currentBalance); /* left */ cannam@89: *out++ = data->sine[data->right_phase] * data->currentBalance; /* right */ cannam@89: cannam@89: data->left_phase += 1; cannam@89: if( data->left_phase >= TABLE_SIZE ) data->left_phase -= TABLE_SIZE; cannam@89: data->right_phase += 3; /* higher pitch so we can distinguish left and right. */ cannam@89: if( data->right_phase >= TABLE_SIZE ) data->right_phase -= TABLE_SIZE; cannam@89: } cannam@89: cannam@89: return finished; cannam@89: } cannam@89: cannam@89: /*******************************************************************/ cannam@89: int main(void); cannam@89: int main(void) cannam@89: { cannam@89: PaStream *stream; cannam@89: PaStreamParameters outputParameters; cannam@89: PaError err; cannam@89: paTestData data; cannam@89: int i; cannam@89: printf("Play different tone sine waves that alternate between left and right channel.\n"); cannam@89: printf("The low tone should be on the left channel.\n"); cannam@89: cannam@89: /* initialise sinusoidal wavetable */ cannam@89: for( i=0; idefaultLowOutputLatency; cannam@89: outputParameters.hostApiSpecificStreamInfo = NULL; cannam@89: cannam@89: err = Pa_OpenStream( &stream, cannam@89: NULL, /* No input. */ cannam@89: &outputParameters, /* As above. */ cannam@89: SAMPLE_RATE, cannam@89: FRAMES_PER_BUFFER, cannam@89: paClipOff, /* we won't output out of range samples so don't bother clipping them */ cannam@89: patestCallback, cannam@89: &data ); cannam@89: if( err != paNoError ) goto error; cannam@89: cannam@89: err = Pa_StartStream( stream ); cannam@89: if( err != paNoError ) goto error; cannam@89: cannam@89: printf("Play for several seconds.\n"); cannam@89: for( i=0; i<4; i++ ) cannam@89: { cannam@89: printf("Hear low sound on left side.\n"); cannam@89: data.targetBalance = 0.01; cannam@89: Pa_Sleep( 1000 ); cannam@89: cannam@89: printf("Hear high sound on right side.\n"); cannam@89: data.targetBalance = 0.99; cannam@89: Pa_Sleep( 1000 ); cannam@89: } cannam@89: cannam@89: err = Pa_StopStream( stream ); cannam@89: if( err != paNoError ) goto error; cannam@89: err = Pa_CloseStream( stream ); cannam@89: if( err != paNoError ) goto error; cannam@89: Pa_Terminate(); cannam@89: printf("Test finished.\n"); cannam@89: return err; cannam@89: error: cannam@89: Pa_Terminate(); cannam@89: fprintf( stderr, "An error occured while using the portaudio stream\n" ); cannam@89: fprintf( stderr, "Error number: %d\n", err ); cannam@89: fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) ); cannam@89: return err; cannam@89: }