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Diffstat (limited to 'portaudio/test/patest_sync.c')
| -rw-r--r-- | portaudio/test/patest_sync.c | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/portaudio/test/patest_sync.c b/portaudio/test/patest_sync.c new file mode 100644 index 0000000..51bbf94 --- /dev/null +++ b/portaudio/test/patest_sync.c @@ -0,0 +1,267 @@ +/** @file patest_sync.c + @ingroup test_src + @brief Test time stamping and synchronization of audio and video. + + A high latency is used so we can hear the difference in time. + Random durations are used so we know we are hearing the right beep + and not the one before or after. + + Sequence of events: + -# Foreground requests a beep. + -# Background randomly schedules a beep. + -# Foreground waits for the beep to be heard based on PaUtil_GetTime(). + -# Foreground outputs video (printf) in sync with audio. + -# Repeat. + + @author Phil Burk http://www.softsynth.com +*/ +/* + * $Id: patest_sync.c 1097 2006-08-26 08:27:53Z rossb $ + * + * 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. + * + * 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. + */ + +/* + * The text above constitutes the entire PortAudio license; however, + * the PortAudio community also makes the following non-binding requests: + * + * 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. It is also + * requested that these non-binding requests be included along with the + * license above. + */ + +#include <stdio.h> +#include <math.h> +#include "portaudio.h" +#include "pa_util.h" +#define NUM_BEEPS (6) +#define SAMPLE_RATE (44100) +#define SAMPLE_PERIOD (1.0/44100.0) +#define FRAMES_PER_BUFFER (256) +#define BEEP_DURATION (400) +#define LATENCY_MSEC (2000) +#define SLEEP_MSEC (10) +#define TIMEOUT_MSEC (15000) + +#define STATE_BKG_IDLE (0) +#define STATE_BKG_PENDING (1) +#define STATE_BKG_BEEPING (2) +typedef struct +{ + float left_phase; + float right_phase; + int state; + volatile int requestBeep; /* Set by foreground, cleared by background. */ + PaTime beepTime; + int beepCount; + double latency; /* For debugging. */ +} +paTestData; + +static unsigned long GenerateRandomNumber( void ); +/************************************************************/ +/* Calculate pseudo-random 32 bit number based on linear congruential method. */ +static unsigned long GenerateRandomNumber( void ) +{ + static unsigned long randSeed = 99887766; /* Change this for different random sequences. */ + randSeed = (randSeed * 196314165) + 907633515; + return randSeed; +} + +/* 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( const void *inputBuffer, void *outputBuffer, + unsigned long framesPerBuffer, + const PaStreamCallbackTimeInfo *timeInfo, + PaStreamCallbackFlags statusFlags, void *userData ) +{ + /* Cast data passed through stream to our structure. */ + paTestData *data = (paTestData*)userData; + float *out = (float*)outputBuffer; + unsigned int i; + (void) inputBuffer; + + data->latency = timeInfo->outputBufferDacTime - timeInfo->currentTime; + + for( i=0; i<framesPerBuffer; i++ ) + { + switch( data->state ) + { + case STATE_BKG_IDLE: + /* Schedule beep at some random time in the future. */ + if( data->requestBeep ) + { + int random = GenerateRandomNumber() >> 14; + data->beepTime = timeInfo->outputBufferDacTime + (( (double)(random + SAMPLE_RATE)) * SAMPLE_PERIOD ); + data->state = STATE_BKG_PENDING; + } + *out++ = 0.0; /* left */ + *out++ = 0.0; /* right */ + break; + + case STATE_BKG_PENDING: + if( (timeInfo->outputBufferDacTime + (i*SAMPLE_PERIOD)) >= data->beepTime ) + { + data->state = STATE_BKG_BEEPING; + data->beepCount = BEEP_DURATION; + data->left_phase = data->right_phase = 0.0; + } + *out++ = 0.0; /* left */ + *out++ = 0.0; /* right */ + break; + + case STATE_BKG_BEEPING: + if( data->beepCount <= 0 ) + { + data->state = STATE_BKG_IDLE; + data->requestBeep = 0; + *out++ = 0.0; /* left */ + *out++ = 0.0; /* right */ + } + else + { + /* Play sawtooth wave. */ + *out++ = data->left_phase; /* left */ + *out++ = data->right_phase; /* right */ + /* Generate simple sawtooth phaser that ranges between -1.0 and 1.0. */ + data->left_phase += 0.01f; + /* When signal reaches top, drop back down. */ + if( data->left_phase >= 1.0f ) data->left_phase -= 2.0f; + /* higher pitch so we can distinguish left and right. */ + data->right_phase += 0.03f; + if( data->right_phase >= 1.0f ) data->right_phase -= 2.0f; + } + data->beepCount -= 1; + break; + + default: + data->state = STATE_BKG_IDLE; + break; + } + } + return 0; +} +/*******************************************************************/ +int main(void); +int main(void) +{ + PaStream *stream; + PaError err; + paTestData DATA; + int i, timeout; + PaTime previousTime; + PaStreamParameters outputParameters; + printf("PortAudio Test: you should see BEEP at the same time you hear it.\n"); + printf("Wait for a few seconds random delay between BEEPs.\n"); + printf("BEEP %d times.\n", NUM_BEEPS ); + /* Initialize our DATA for use by callback. */ + DATA.left_phase = DATA.right_phase = 0.0; + DATA.state = STATE_BKG_IDLE; + DATA.requestBeep = 0; + /* Initialize library before making any other calls. */ + err = Pa_Initialize(); + if( err != paNoError ) goto error; + + outputParameters.device = Pa_GetDefaultOutputDevice(); + outputParameters.channelCount = 2; + outputParameters.hostApiSpecificStreamInfo = NULL; + outputParameters.sampleFormat = paFloat32; + outputParameters.suggestedLatency = (double)LATENCY_MSEC / 1000; + + /* Open an audio I/O stream. */ + err = Pa_OpenStream( + &stream, + NULL, /* no input */ + &outputParameters, + SAMPLE_RATE, + FRAMES_PER_BUFFER, /* frames per buffer */ + 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; + + printf("started\n"); + fflush(stdout); + + previousTime = Pa_GetStreamTime( stream ); + for( i=0; i<NUM_BEEPS; i++ ) + { + /* Request a beep from background. */ + DATA.requestBeep = 1; + + /* Wait for background to acknowledge request. */ + timeout = TIMEOUT_MSEC; + while( (DATA.requestBeep == 1) && (timeout-- > 0 ) ) Pa_Sleep(SLEEP_MSEC); + if( timeout <= 0 ) + { + fprintf( stderr, "Timed out waiting for background to acknowledge request.\n" ); + goto error; + } + printf("calc beep for %9.3f, latency = %6.3f\n", DATA.beepTime, DATA.latency ); + fflush(stdout); + + /* Wait for scheduled beep time. */ + timeout = TIMEOUT_MSEC + (10000/SLEEP_MSEC); + while( (Pa_GetStreamTime( stream ) < DATA.beepTime) && (timeout-- > 0 ) ) + { + Pa_Sleep(SLEEP_MSEC); + } + if( timeout <= 0 ) + { + fprintf( stderr, "Timed out waiting for time. Now = %9.3f, Beep for %9.3f.\n", + PaUtil_GetTime(), DATA.beepTime ); + goto error; + } + + /* Beep should be sounding now so print synchronized BEEP. */ + printf("hear \"BEEP\" at %9.3f, delta = %9.3f\n", + Pa_GetStreamTime( stream ), (DATA.beepTime - previousTime) ); + fflush(stdout); + + previousTime = DATA.beepTime; + } + + err = Pa_StopStream( stream ); + if( err != paNoError ) goto error; + + err = Pa_CloseStream( stream ); + if( err != paNoError ) goto error; + + 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; +} |