git.sesse.net Git - mlt/blob - src/modules/sdl/consumer_sdl_audio.c

   1 /*
   2  * consumer_sdl_audio.c -- A Simple DirectMedia Layer audio-only consumer
   3  * Copyright (C) 2009 Ushodaya Enterprises Limited
   4  * Author: Dan Dennedy <dan@dennedy.org>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include <framework/mlt_consumer.h>
  22 #include <framework/mlt_frame.h>
  23 #include <framework/mlt_deque.h>
  24 #include <framework/mlt_factory.h>
  25 #include <framework/mlt_filter.h>
  26 #include <framework/mlt_log.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <pthread.h>
  31 #include <SDL/SDL.h>
  32 #include <sys/time.h>
  33
  34 /** This classes definition.
  35 */
  36
  37 typedef struct consumer_sdl_s *consumer_sdl;
  38
  39 struct consumer_sdl_s
  40 {
  41         struct mlt_consumer_s parent;
  42         mlt_properties properties;
  43         mlt_deque queue;
  44         pthread_t thread;
  45         int joined;
  46         int running;
  47         uint8_t audio_buffer[ 4096 * 10 ];
  48         int audio_avail;
  49         pthread_mutex_t audio_mutex;
  50         pthread_cond_t audio_cond;
  51         pthread_mutex_t video_mutex;
  52         pthread_cond_t video_cond;
  53         int playing;
  54
  55         pthread_cond_t refresh_cond;
  56         pthread_mutex_t refresh_mutex;
  57         int refresh_count;
  58 };
  59
  60 /** Forward references to static functions.
  61 */
  62
  63 static int consumer_start( mlt_consumer parent );
  64 static int consumer_stop( mlt_consumer parent );
  65 static int consumer_is_stopped( mlt_consumer parent );
  66 static void consumer_close( mlt_consumer parent );
  67 static void *consumer_thread( void * );
  68 static void consumer_refresh_cb( mlt_consumer sdl, mlt_consumer this, char *name );
  69
  70 /** This is what will be called by the factory - anything can be passed in
  71         via the argument, but keep it simple.
  72 */
  73
  74 mlt_consumer consumer_sdl_audio_init( mlt_profile profile, mlt_service_type type, const char *id, char *arg )
  75 {
  76         // Create the consumer object
  77         consumer_sdl this = calloc( sizeof( struct consumer_sdl_s ), 1 );
  78
  79         // If no malloc'd and consumer init ok
  80         if ( this != NULL && mlt_consumer_init( &this->parent, this, profile ) == 0 )
  81         {
  82                 // Create the queue
  83                 this->queue = mlt_deque_init( );
  84
  85                 // Get the parent consumer object
  86                 mlt_consumer parent = &this->parent;
  87
  88                 // We have stuff to clean up, so override the close method
  89                 parent->close = consumer_close;
  90
  91                 // get a handle on properties
  92                 mlt_service service = MLT_CONSUMER_SERVICE( parent );
  93                 this->properties = MLT_SERVICE_PROPERTIES( service );
  94
  95                 // Set the default volume
  96                 mlt_properties_set_double( this->properties, "volume", 1.0 );
  97
  98                 // This is the initialisation of the consumer
  99                 pthread_mutex_init( &this->audio_mutex, NULL );
 100                 pthread_cond_init( &this->audio_cond, NULL);
 101                 pthread_mutex_init( &this->video_mutex, NULL );
 102                 pthread_cond_init( &this->video_cond, NULL);
 103
 104                 // Default scaler (for now we'll use nearest)
 105                 mlt_properties_set( this->properties, "rescale", "nearest" );
 106
 107                 // Default buffer for low latency
 108                 mlt_properties_set_int( this->properties, "buffer", 1 );
 109
 110                 // Default audio buffer
 111                 mlt_properties_set_int( this->properties, "audio_buffer", 512 );
 112
 113                 // Ensure we don't join on a non-running object
 114                 this->joined = 1;
 115
 116                 // Allow thread to be started/stopped
 117                 parent->start = consumer_start;
 118                 parent->stop = consumer_stop;
 119                 parent->is_stopped = consumer_is_stopped;
 120
 121                 // Initialize the refresh handler
 122                 pthread_cond_init( &this->refresh_cond, NULL );
 123                 pthread_mutex_init( &this->refresh_mutex, NULL );
 124                 mlt_events_listen( MLT_CONSUMER_PROPERTIES( parent ), this, "property-changed", ( mlt_listener )consumer_refresh_cb );
 125
 126                 // Return the consumer produced
 127                 return parent;
 128         }
 129
 130         // malloc or consumer init failed
 131         free( this );
 132
 133         // Indicate failure
 134         return NULL;
 135 }
 136
 137 static void consumer_refresh_cb( mlt_consumer sdl, mlt_consumer parent, char *name )
 138 {
 139         if ( !strcmp( name, "refresh" ) )
 140         {
 141                 consumer_sdl this = parent->child;
 142                 pthread_mutex_lock( &this->refresh_mutex );
 143                 this->refresh_count = this->refresh_count <= 0 ? 1 : this->refresh_count ++;
 144                 pthread_cond_broadcast( &this->refresh_cond );
 145                 pthread_mutex_unlock( &this->refresh_mutex );
 146         }
 147 }
 148
 149 int consumer_start( mlt_consumer parent )
 150 {
 151         consumer_sdl this = parent->child;
 152
 153         if ( !this->running )
 154         {
 155                 consumer_stop( parent );
 156
 157                 this->running = 1;
 158                 this->joined = 0;
 159
 160                 if ( SDL_Init( SDL_INIT_AUDIO | SDL_INIT_NOPARACHUTE ) < 0 )
 161                 {
 162                         mlt_log_error( MLT_CONSUMER_SERVICE(parent), "Failed to initialize SDL: %s\n", SDL_GetError() );
 163                         return -1;
 164                 }
 165
 166                 pthread_create( &this->thread, NULL, consumer_thread, this );
 167         }
 168
 169         return 0;
 170 }
 171
 172 int consumer_stop( mlt_consumer parent )
 173 {
 174         // Get the actual object
 175         consumer_sdl this = parent->child;
 176
 177         if ( this->joined == 0 )
 178         {
 179                 // Kill the thread and clean up
 180                 this->joined = 1;
 181                 this->running = 0;
 182
 183                 // Unlatch the consumer thread
 184                 pthread_mutex_lock( &this->refresh_mutex );
 185                 pthread_cond_broadcast( &this->refresh_cond );
 186                 pthread_mutex_unlock( &this->refresh_mutex );
 187
 188                 // Cleanup the main thread
 189                 if ( this->thread )
 190                         pthread_join( this->thread, NULL );
 191
 192                 // Unlatch the audio callback
 193                 pthread_mutex_lock( &this->audio_mutex );
 194                 pthread_cond_broadcast( &this->audio_cond );
 195                 pthread_mutex_unlock( &this->audio_mutex );
 196
 197                 SDL_QuitSubSystem( SDL_INIT_AUDIO );
 198         }
 199
 200         return 0;
 201 }
 202
 203 int consumer_is_stopped( mlt_consumer parent )
 204 {
 205         consumer_sdl this = parent->child;
 206         return !this->running;
 207 }
 208
 209 static void sdl_fill_audio( void *udata, uint8_t *stream, int len )
 210 {
 211         consumer_sdl this = udata;
 212
 213         // Get the volume
 214         double volume = mlt_properties_get_double( this->properties, "volume" );
 215
 216         pthread_mutex_lock( &this->audio_mutex );
 217
 218         // Block until audio received
 219         while ( this->running && len > this->audio_avail )
 220                 pthread_cond_wait( &this->audio_cond, &this->audio_mutex );
 221
 222         if ( this->audio_avail >= len )
 223         {
 224                 // Place in the audio buffer
 225                 if ( volume != 1.0 )
 226                         SDL_MixAudio( stream, this->audio_buffer, len, ( int )( ( float )SDL_MIX_MAXVOLUME * volume ) );
 227                 else
 228                         memcpy( stream, this->audio_buffer, len );
 229
 230                 // Remove len from the audio available
 231                 this->audio_avail -= len;
 232
 233                 // Remove the samples
 234                 memmove( this->audio_buffer, this->audio_buffer + len, this->audio_avail );
 235         }
 236         else
 237         {
 238                 // Just to be safe, wipe the stream first
 239                 memset( stream, 0, len );
 240
 241                 // Mix the audio
 242                 SDL_MixAudio( stream, this->audio_buffer, len, ( int )( ( float )SDL_MIX_MAXVOLUME * volume ) );
 243
 244                 // No audio left
 245                 this->audio_avail = 0;
 246         }
 247
 248         // We're definitely playing now
 249         this->playing = 1;
 250
 251         pthread_cond_broadcast( &this->audio_cond );
 252         pthread_mutex_unlock( &this->audio_mutex );
 253 }
 254
 255 static int consumer_play_audio( consumer_sdl this, mlt_frame frame, int init_audio, int *duration )
 256 {
 257         // Get the properties of this consumer
 258         mlt_properties properties = this->properties;
 259         mlt_audio_format afmt = mlt_audio_pcm;
 260
 261         // Set the preferred params of the test card signal
 262         int channels = mlt_properties_get_int( properties, "channels" );
 263         int frequency = mlt_properties_get_int( properties, "frequency" );
 264         static int counter = 0;
 265
 266         int samples = mlt_sample_calculator( mlt_properties_get_double( this->properties, "fps" ), frequency, counter++ );
 267
 268         int16_t *pcm;
 269         int bytes;
 270
 271         mlt_frame_get_audio( frame, &pcm, &afmt, &frequency, &channels, &samples );
 272         *duration = ( ( samples * 1000 ) / frequency );
 273
 274         if ( mlt_properties_get_int( properties, "audio_off" ) )
 275         {
 276                 this->playing = 1;
 277                 init_audio = 1;
 278                 return init_audio;
 279         }
 280
 281         if ( init_audio == 1 )
 282         {
 283                 SDL_AudioSpec request;
 284                 SDL_AudioSpec got;
 285
 286                 int audio_buffer = mlt_properties_get_int( properties, "audio_buffer" );
 287
 288                 // specify audio format
 289                 memset( &request, 0, sizeof( SDL_AudioSpec ) );
 290                 this->playing = 0;
 291                 request.freq = frequency;
 292                 request.format = AUDIO_S16SYS;
 293                 request.channels = channels;
 294                 request.samples = audio_buffer;
 295                 request.callback = sdl_fill_audio;
 296                 request.userdata = (void *)this;
 297                 if ( SDL_OpenAudio( &request, &got ) != 0 )
 298                 {
 299                         mlt_log_error( MLT_CONSUMER_SERVICE( this ), "SDL failed to open audio: %s\n", SDL_GetError() );
 300                         init_audio = 2;
 301                 }
 302                 else if ( got.size != 0 )
 303                 {
 304                         SDL_PauseAudio( 0 );
 305                         init_audio = 0;
 306                 }
 307         }
 308
 309         if ( init_audio == 0 )
 310         {
 311                 mlt_properties properties = MLT_FRAME_PROPERTIES( frame );
 312                 bytes = ( samples * channels * 2 );
 313                 pthread_mutex_lock( &this->audio_mutex );
 314                 while ( this->running && bytes > ( sizeof( this->audio_buffer) - this->audio_avail ) )
 315                         pthread_cond_wait( &this->audio_cond, &this->audio_mutex );
 316                 if ( this->running )
 317                 {
 318                         if ( mlt_properties_get_double( properties, "_speed" ) == 1 )
 319                                 memcpy( &this->audio_buffer[ this->audio_avail ], pcm, bytes );
 320                         else
 321                                 memset( &this->audio_buffer[ this->audio_avail ], 0, bytes );
 322                         this->audio_avail += bytes;
 323                 }
 324                 pthread_cond_broadcast( &this->audio_cond );
 325                 pthread_mutex_unlock( &this->audio_mutex );
 326         }
 327         else
 328         {
 329                 this->playing = 1;
 330         }
 331
 332         return init_audio;
 333 }
 334
 335 static int consumer_play_video( consumer_sdl this, mlt_frame frame )
 336 {
 337         // Get the properties of this consumer
 338         mlt_properties properties = this->properties;
 339         if ( this->running && !mlt_consumer_is_stopped( &this->parent ) )
 340                 mlt_events_fire( properties, "consumer-frame-show", frame, NULL );
 341
 342         return 0;
 343 }
 344
 345 static void *video_thread( void *arg )
 346 {
 347         // Identify the arg
 348         consumer_sdl this = arg;
 349
 350         // Obtain time of thread start
 351         struct timeval now;
 352         int64_t start = 0;
 353         int64_t elapsed = 0;
 354         struct timespec tm;
 355         mlt_frame next = NULL;
 356         mlt_properties properties = NULL;
 357         double speed = 0;
 358
 359         // Get real time flag
 360         int real_time = mlt_properties_get_int( this->properties, "real_time" );
 361
 362         // Get the current time
 363         gettimeofday( &now, NULL );
 364
 365         // Determine start time
 366         start = ( int64_t )now.tv_sec * 1000000 + now.tv_usec;
 367
 368         while ( this->running )
 369         {
 370                 // Pop the next frame
 371                 pthread_mutex_lock( &this->video_mutex );
 372                 next = mlt_deque_pop_front( this->queue );
 373                 while ( next == NULL && this->running )
 374                 {
 375                         pthread_cond_wait( &this->video_cond, &this->video_mutex );
 376                         next = mlt_deque_pop_front( this->queue );
 377                 }
 378                 pthread_mutex_unlock( &this->video_mutex );
 379
 380                 if ( !this->running || next == NULL ) break;
 381
 382                 // Get the properties
 383                 properties =  MLT_FRAME_PROPERTIES( next );
 384
 385                 // Get the speed of the frame
 386                 speed = mlt_properties_get_double( properties, "_speed" );
 387
 388                 // Get the current time
 389                 gettimeofday( &now, NULL );
 390
 391                 // Get the elapsed time
 392                 elapsed = ( ( int64_t )now.tv_sec * 1000000 + now.tv_usec ) - start;
 393
 394                 // See if we have to delay the display of the current frame
 395                 if ( mlt_properties_get_int( properties, "rendered" ) == 1 && this->running )
 396                 {
 397                         // Obtain the scheduled playout time
 398                         int64_t scheduled = mlt_properties_get_int( properties, "playtime" );
 399
 400                         // Determine the difference between the elapsed time and the scheduled playout time
 401                         int64_t difference = scheduled - elapsed;
 402
 403                         // Smooth playback a bit
 404                         if ( real_time && ( difference > 20000 && speed == 1.0 ) )
 405                         {
 406                                 tm.tv_sec = difference / 1000000;
 407                                 tm.tv_nsec = ( difference % 1000000 ) * 500;
 408                                 nanosleep( &tm, NULL );
 409                         }
 410
 411                         // Show current frame if not too old
 412                         if ( !real_time || ( difference > -10000 || speed != 1.0 || mlt_deque_count( this->queue ) < 2 ) )
 413                                 consumer_play_video( this, next );
 414
 415                         // If the queue is empty, recalculate start to allow build up again
 416                         if ( real_time && ( mlt_deque_count( this->queue ) == 0 && speed == 1.0 ) )
 417                         {
 418                                 gettimeofday( &now, NULL );
 419                                 start = ( ( int64_t )now.tv_sec * 1000000 + now.tv_usec ) - scheduled + 20000;
 420                         }
 421                 }
 422
 423                 // This frame can now be closed
 424                 mlt_frame_close( next );
 425                 next = NULL;
 426         }
 427
 428         if ( next != NULL )
 429                 mlt_frame_close( next );
 430
 431         mlt_consumer_stopped( &this->parent );
 432
 433         return NULL;
 434 }
 435
 436 /** Threaded wrapper for pipe.
 437 */
 438
 439 static void *consumer_thread( void *arg )
 440 {
 441         // Identify the arg
 442         consumer_sdl this = arg;
 443
 444         // Get the consumer
 445         mlt_consumer consumer = &this->parent;
 446
 447         // Get the properties
 448         mlt_properties consumer_props = MLT_CONSUMER_PROPERTIES( consumer );
 449
 450         // Video thread
 451         pthread_t thread;
 452
 453         // internal intialization
 454         int init_audio = 1;
 455         int init_video = 1;
 456         mlt_frame frame = NULL;
 457         mlt_properties properties = NULL;
 458         int duration = 0;
 459         int64_t playtime = 0;
 460         struct timespec tm = { 0, 100000 };
 461         int last_position = -1;
 462         this->refresh_count = 0;
 463
 464         // Loop until told not to
 465         while( this->running )
 466         {
 467                 // Get a frame from the attached producer
 468                 frame = mlt_consumer_rt_frame( consumer );
 469
 470                 // Ensure that we have a frame
 471                 if ( frame )
 472                 {
 473                         // Get the frame properties
 474                         properties =  MLT_FRAME_PROPERTIES( frame );
 475
 476                         // Get the speed of the frame
 477                         double speed = mlt_properties_get_double( properties, "_speed" );
 478
 479                         // Get refresh request for the current frame
 480                         int refresh = mlt_properties_get_int( consumer_props, "refresh" );
 481
 482                         // Clear refresh
 483                         mlt_events_block( consumer_props, consumer_props );
 484                         mlt_properties_set_int( consumer_props, "refresh", 0 );
 485                         mlt_events_unblock( consumer_props, consumer_props );
 486
 487                         // Play audio
 488                         init_audio = consumer_play_audio( this, frame, init_audio, &duration );
 489
 490                         // Determine the start time now
 491                         if ( this->playing && init_video )
 492                         {
 493                                 // Create the video thread
 494                                 pthread_create( &thread, NULL, video_thread, this );
 495
 496                                 // Video doesn't need to be initialised any more
 497                                 init_video = 0;
 498                         }
 499
 500                         // Set playtime for this frame
 501                         mlt_properties_set_int( properties, "playtime", playtime );
 502
 503                         while ( this->running && speed != 0 && mlt_deque_count( this->queue ) > 15 )
 504                                 nanosleep( &tm, NULL );
 505
 506                         // Push this frame to the back of the queue
 507                         if ( this->running && speed )
 508                         {
 509                                 pthread_mutex_lock( &this->video_mutex );
 510                                 mlt_deque_push_back( this->queue, frame );
 511                                 pthread_cond_broadcast( &this->video_cond );
 512                                 pthread_mutex_unlock( &this->video_mutex );
 513
 514                                 // Calculate the next playtime
 515                                 playtime += ( duration * 1000 );
 516                         }
 517                         else if ( this->running )
 518                         {
 519                                 pthread_mutex_lock( &this->refresh_mutex );
 520                                 if ( refresh == 0 && this->refresh_count <= 0 )
 521                                 {
 522                                         consumer_play_video( this, frame );
 523                                         pthread_cond_wait( &this->refresh_cond, &this->refresh_mutex );
 524                                 }
 525                                 this->refresh_count --;
 526                                 pthread_mutex_unlock( &this->refresh_mutex );
 527                         }
 528
 529                         // Optimisation to reduce latency
 530                         if ( speed == 1.0 )
 531                         {
 532                                 if ( last_position != -1 && last_position + 1 != mlt_frame_get_position( frame ) )
 533                                         mlt_consumer_purge( consumer );
 534                                 last_position = mlt_frame_get_position( frame );
 535                         }
 536                         else
 537                         {
 538                                 mlt_consumer_purge( consumer );
 539                                 last_position = -1;
 540                         }
 541                 }
 542         }
 543
 544         // Kill the video thread
 545         if ( init_video == 0 )
 546         {
 547                 pthread_mutex_lock( &this->video_mutex );
 548                 pthread_cond_broadcast( &this->video_cond );
 549                 pthread_mutex_unlock( &this->video_mutex );
 550                 pthread_join( thread, NULL );
 551         }
 552
 553         while( mlt_deque_count( this->queue ) )
 554                 mlt_frame_close( mlt_deque_pop_back( this->queue ) );
 555
 556         this->audio_avail = 0;
 557
 558         return NULL;
 559 }
 560
 561 /** Callback to allow override of the close method.
 562 */
 563
 564 static void consumer_close( mlt_consumer parent )
 565 {
 566         // Get the actual object
 567         consumer_sdl this = parent->child;
 568
 569         // Stop the consumer
 570         mlt_consumer_stop( parent );
 571
 572         // Now clean up the rest
 573         mlt_consumer_close( parent );
 574
 575         // Close the queue
 576         mlt_deque_close( this->queue );
 577
 578         // Destroy mutexes
 579         pthread_mutex_destroy( &this->audio_mutex );
 580         pthread_cond_destroy( &this->audio_cond );
 581
 582         // Finally clean up this
 583         free( this );
 584 }