Chris@39: /** @file Chris@39: @ingroup test_src Chris@39: @brief Hear the latency caused by big buffers. Chris@39: Play a sine wave and change frequency based on letter input. Chris@39: @author Phil Burk , and Darren Gibbs Chris@39: */ Chris@39: /* Chris@39: * $Id: patest_latency.c 1368 2008-03-01 00:38:27Z rossb $ Chris@39: * Chris@39: * This program uses the PortAudio Portable Audio Library. Chris@39: * For more information see: http://www.portaudio.com Chris@39: * Copyright (c) 1999-2000 Ross Bencina and Phil Burk Chris@39: * Chris@39: * Permission is hereby granted, free of charge, to any person obtaining Chris@39: * a copy of this software and associated documentation files Chris@39: * (the "Software"), to deal in the Software without restriction, Chris@39: * including without limitation the rights to use, copy, modify, merge, Chris@39: * publish, distribute, sublicense, and/or sell copies of the Software, Chris@39: * and to permit persons to whom the Software is furnished to do so, Chris@39: * subject to the following conditions: Chris@39: * Chris@39: * The above copyright notice and this permission notice shall be Chris@39: * included in all copies or substantial portions of the Software. Chris@39: * Chris@39: * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, Chris@39: * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF Chris@39: * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. Chris@39: * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR Chris@39: * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF Chris@39: * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION Chris@39: * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Chris@39: */ Chris@39: Chris@39: /* Chris@39: * The text above constitutes the entire PortAudio license; however, Chris@39: * the PortAudio community also makes the following non-binding requests: Chris@39: * Chris@39: * Any person wishing to distribute modifications to the Software is Chris@39: * requested to send the modifications to the original developer so that Chris@39: * they can be incorporated into the canonical version. It is also Chris@39: * requested that these non-binding requests be included along with the Chris@39: * license above. Chris@39: */ Chris@39: Chris@39: #include Chris@39: #include Chris@39: #include "portaudio.h" Chris@39: Chris@39: #define OUTPUT_DEVICE (Pa_GetDefaultOutputDevice()) Chris@39: #define SAMPLE_RATE (44100) Chris@39: #define FRAMES_PER_BUFFER (64) Chris@39: Chris@39: #define MIN_FREQ (100.0f) Chris@39: #define CalcPhaseIncrement(freq) ((freq)/SAMPLE_RATE) Chris@39: #ifndef M_PI Chris@39: #define M_PI (3.14159265) Chris@39: #endif Chris@39: #define TABLE_SIZE (400) Chris@39: Chris@39: typedef struct Chris@39: { Chris@39: float sine[TABLE_SIZE + 1]; /* add one for guard point for interpolation */ Chris@39: float phase_increment; Chris@39: float left_phase; Chris@39: float right_phase; Chris@39: } Chris@39: paTestData; Chris@39: Chris@39: float LookupSine( paTestData *data, float phase ); Chris@39: /* Convert phase between and 1.0 to sine value Chris@39: * using linear interpolation. Chris@39: */ Chris@39: float LookupSine( paTestData *data, float phase ) Chris@39: { Chris@39: float fIndex = phase*TABLE_SIZE; Chris@39: int index = (int) fIndex; Chris@39: float fract = fIndex - index; Chris@39: float lo = data->sine[index]; Chris@39: float hi = data->sine[index+1]; Chris@39: float val = lo + fract*(hi-lo); Chris@39: return val; Chris@39: } Chris@39: Chris@39: /* This routine will be called by the PortAudio engine when audio is needed. Chris@39: ** It may called at interrupt level on some machines so don't do anything Chris@39: ** that could mess up the system like calling malloc() or free(). Chris@39: */ Chris@39: static int patestCallback( const void *inputBuffer, void *outputBuffer, Chris@39: unsigned long framesPerBuffer, Chris@39: const PaStreamCallbackTimeInfo* timeInfo, Chris@39: PaStreamCallbackFlags statusFlags, Chris@39: void *userData ) Chris@39: { Chris@39: paTestData *data = (paTestData*)userData; Chris@39: float *out = (float*)outputBuffer; Chris@39: int i; Chris@39: Chris@39: (void) inputBuffer; /* Prevent unused variable warning. */ Chris@39: Chris@39: for( i=0; ileft_phase); /* left */ Chris@39: *out++ = LookupSine(data, data->right_phase); /* right */ Chris@39: data->left_phase += data->phase_increment; Chris@39: if( data->left_phase >= 1.0f ) data->left_phase -= 1.0f; Chris@39: data->right_phase += (data->phase_increment * 1.5f); /* fifth above */ Chris@39: if( data->right_phase >= 1.0f ) data->right_phase -= 1.0f; Chris@39: } Chris@39: return 0; Chris@39: } Chris@39: Chris@39: /*******************************************************************/ Chris@39: int main(void); Chris@39: int main(void) Chris@39: { Chris@39: PaStream *stream; Chris@39: PaStreamParameters outputParameters; Chris@39: PaError err; Chris@39: paTestData data; Chris@39: int i; Chris@39: int done = 0; Chris@39: Chris@39: printf("PortAudio Test: enter letter then hit ENTER.\n" ); Chris@39: /* initialise sinusoidal wavetable */ Chris@39: for( i=0; idefaultLowOutputLatency; Chris@39: outputParameters.hostApiSpecificStreamInfo = NULL; Chris@39: Chris@39: printf("Requested output latency = %.4f seconds.\n", outputParameters.suggestedLatency ); Chris@39: printf("%d frames per buffer.\n.", FRAMES_PER_BUFFER ); Chris@39: Chris@39: err = Pa_OpenStream( Chris@39: &stream, Chris@39: NULL, /* no input */ Chris@39: &outputParameters, Chris@39: SAMPLE_RATE, Chris@39: FRAMES_PER_BUFFER, Chris@39: paClipOff|paDitherOff, /* we won't output out of range samples so don't bother clipping them */ Chris@39: patestCallback, Chris@39: &data ); Chris@39: if( err != paNoError ) goto error; Chris@39: Chris@39: err = Pa_StartStream( stream ); Chris@39: if( err != paNoError ) goto error; Chris@39: printf("Play ASCII keyboard. Hit 'q' to stop. (Use RETURN key on Mac)\n"); Chris@39: fflush(stdout); Chris@39: while ( !done ) Chris@39: { Chris@39: float freq; Chris@39: int index; Chris@39: char c; Chris@39: do Chris@39: { Chris@39: c = getchar(); Chris@39: } Chris@39: while( c < ' '); /* Strip white space and control chars. */ Chris@39: Chris@39: if( c == 'q' ) done = 1; Chris@39: index = c % 26; Chris@39: freq = MIN_FREQ + (index * 40.0); Chris@39: data.phase_increment = CalcPhaseIncrement(freq); Chris@39: } Chris@39: printf("Call Pa_StopStream()\n"); Chris@39: err = Pa_StopStream( stream ); Chris@39: if( err != paNoError ) goto error; Chris@39: Pa_Terminate(); Chris@39: printf("Test finished.\n"); Chris@39: return err; Chris@39: error: Chris@39: Pa_Terminate(); Chris@39: fprintf( stderr, "An error occured while using the portaudio stream\n" ); Chris@39: fprintf( stderr, "Error number: %d\n", err ); Chris@39: fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) ); Chris@39: return err; Chris@39: }