cannam@162: /** @file patest_leftright.c cannam@162: @ingroup test_src cannam@162: @brief Play different tone sine waves that cannam@162: alternate between left and right channel. cannam@162: cannam@162: The low tone should be on the left channel. cannam@162: cannam@162: @author Ross Bencina cannam@162: @author Phil Burk cannam@162: */ cannam@162: /* cannam@162: * $Id$ cannam@162: * cannam@162: * This program uses the PortAudio Portable Audio Library. cannam@162: * For more information see: http://www.portaudio.com cannam@162: * Copyright (c) 1999-2000 Ross Bencina and Phil Burk cannam@162: * cannam@162: * Permission is hereby granted, free of charge, to any person obtaining cannam@162: * a copy of this software and associated documentation files cannam@162: * (the "Software"), to deal in the Software without restriction, cannam@162: * including without limitation the rights to use, copy, modify, merge, cannam@162: * publish, distribute, sublicense, and/or sell copies of the Software, cannam@162: * and to permit persons to whom the Software is furnished to do so, cannam@162: * subject to the following conditions: cannam@162: * cannam@162: * The above copyright notice and this permission notice shall be cannam@162: * included in all copies or substantial portions of the Software. cannam@162: * cannam@162: * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, cannam@162: * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF cannam@162: * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. cannam@162: * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR cannam@162: * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF cannam@162: * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION cannam@162: * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. cannam@162: */ cannam@162: cannam@162: /* cannam@162: * The text above constitutes the entire PortAudio license; however, cannam@162: * the PortAudio community also makes the following non-binding requests: cannam@162: * cannam@162: * Any person wishing to distribute modifications to the Software is cannam@162: * requested to send the modifications to the original developer so that cannam@162: * they can be incorporated into the canonical version. It is also cannam@162: * requested that these non-binding requests be included along with the cannam@162: * license above. cannam@162: */ cannam@162: cannam@162: #include cannam@162: #include cannam@162: #include "portaudio.h" cannam@162: cannam@162: #define NUM_SECONDS (8) cannam@162: #define SAMPLE_RATE (44100) cannam@162: #define FRAMES_PER_BUFFER (512) cannam@162: #ifndef M_PI cannam@162: #define M_PI (3.14159265) cannam@162: #endif cannam@162: #define TABLE_SIZE (200) cannam@162: #define BALANCE_DELTA (0.001) cannam@162: cannam@162: typedef struct cannam@162: { cannam@162: float sine[TABLE_SIZE]; cannam@162: int left_phase; cannam@162: int right_phase; cannam@162: float targetBalance; // 0.0 = left, 1.0 = right cannam@162: float currentBalance; cannam@162: } paTestData; cannam@162: cannam@162: /* This routine will be called by the PortAudio engine when audio is needed. cannam@162: ** It may called at interrupt level on some machines so don't do anything cannam@162: ** that could mess up the system like calling malloc() or free(). cannam@162: */ cannam@162: static int patestCallback( const void *inputBuffer, cannam@162: void *outputBuffer, cannam@162: unsigned long framesPerBuffer, cannam@162: const PaStreamCallbackTimeInfo* timeInfo, cannam@162: PaStreamCallbackFlags statusFlags, cannam@162: void *userData ) cannam@162: { cannam@162: paTestData *data = (paTestData*)userData; cannam@162: float *out = (float*)outputBuffer; cannam@162: unsigned long i; cannam@162: int finished = 0; cannam@162: /* Prevent unused variable warnings. */ cannam@162: (void) inputBuffer; cannam@162: cannam@162: for( i=0; icurrentBalance < data->targetBalance ) cannam@162: { cannam@162: data->currentBalance += BALANCE_DELTA; cannam@162: } cannam@162: else if( data->currentBalance > data->targetBalance ) cannam@162: { cannam@162: data->currentBalance -= BALANCE_DELTA; cannam@162: } cannam@162: // Apply left/right balance. cannam@162: *out++ = data->sine[data->left_phase] * (1.0f - data->currentBalance); /* left */ cannam@162: *out++ = data->sine[data->right_phase] * data->currentBalance; /* right */ cannam@162: cannam@162: data->left_phase += 1; cannam@162: if( data->left_phase >= TABLE_SIZE ) data->left_phase -= TABLE_SIZE; cannam@162: data->right_phase += 3; /* higher pitch so we can distinguish left and right. */ cannam@162: if( data->right_phase >= TABLE_SIZE ) data->right_phase -= TABLE_SIZE; cannam@162: } cannam@162: cannam@162: return finished; cannam@162: } cannam@162: cannam@162: /*******************************************************************/ cannam@162: int main(void); cannam@162: int main(void) cannam@162: { cannam@162: PaStream *stream; cannam@162: PaStreamParameters outputParameters; cannam@162: PaError err; cannam@162: paTestData data; cannam@162: int i; cannam@162: printf("Play different tone sine waves that alternate between left and right channel.\n"); cannam@162: printf("The low tone should be on the left channel.\n"); cannam@162: cannam@162: /* initialise sinusoidal wavetable */ cannam@162: for( i=0; idefaultLowOutputLatency; cannam@162: outputParameters.hostApiSpecificStreamInfo = NULL; cannam@162: cannam@162: err = Pa_OpenStream( &stream, cannam@162: NULL, /* No input. */ cannam@162: &outputParameters, /* As above. */ cannam@162: SAMPLE_RATE, cannam@162: FRAMES_PER_BUFFER, cannam@162: paClipOff, /* we won't output out of range samples so don't bother clipping them */ cannam@162: patestCallback, cannam@162: &data ); cannam@162: if( err != paNoError ) goto error; cannam@162: cannam@162: err = Pa_StartStream( stream ); cannam@162: if( err != paNoError ) goto error; cannam@162: cannam@162: printf("Play for several seconds.\n"); cannam@162: for( i=0; i<4; i++ ) cannam@162: { cannam@162: printf("Hear low sound on left side.\n"); cannam@162: data.targetBalance = 0.01; cannam@162: Pa_Sleep( 1000 ); cannam@162: cannam@162: printf("Hear high sound on right side.\n"); cannam@162: data.targetBalance = 0.99; cannam@162: Pa_Sleep( 1000 ); cannam@162: } cannam@162: cannam@162: err = Pa_StopStream( stream ); cannam@162: if( err != paNoError ) goto error; cannam@162: err = Pa_CloseStream( stream ); cannam@162: if( err != paNoError ) goto error; cannam@162: Pa_Terminate(); cannam@162: printf("Test finished.\n"); cannam@162: return err; cannam@162: error: cannam@162: Pa_Terminate(); cannam@162: fprintf( stderr, "An error occured while using the portaudio stream\n" ); cannam@162: fprintf( stderr, "Error number: %d\n", err ); cannam@162: fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) ); cannam@162: return err; cannam@162: }