272 lines
		
	
	
		
			9.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			272 lines
		
	
	
		
			9.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /** @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
 | ||
|  | */ | ||
|  | /*
 | ||
|  |  * $Id$ | ||
|  |  * | ||
|  |  * 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(); | ||
|  |     if (outputParameters.device == paNoDevice) { | ||
|  |         fprintf(stderr,"Error: No default output device.\n"); | ||
|  |         goto error; | ||
|  |     } | ||
|  |     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 occurred while using the portaudio stream\n" ); | ||
|  |     fprintf( stderr, "Error number: %d\n", err ); | ||
|  |     fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) ); | ||
|  |     return err; | ||
|  | } |