git.sesse.net Git - mlt/blob - src/framework/mlt_consumer.c

   1 /**
   2  * \file mlt_consumer.c
   3  * \brief abstraction for all consumer services
   4  * \see mlt_consumer_s
   5  *
   6  * Copyright (C) 2003-2010 Ushodaya Enterprises Limited
   7  * \author Charles Yates <charles.yates@pandora.be>
   8  * \author Dan Dennedy <dan@dennedy.org>
   9  *
  10  * This library is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * This library is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with this library; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23  */
  24
  25 #include "mlt_consumer.h"
  26 #include "mlt_factory.h"
  27 #include "mlt_producer.h"
  28 #include "mlt_frame.h"
  29 #include "mlt_profile.h"
  30 #include "mlt_log.h"
  31
  32 #include <stdio.h>
  33 #include <string.h>
  34 #include <stdlib.h>
  35 #include <sys/time.h>
  36
  37 /** Define this if you want an automatic deinterlace (if necessary) when the
  38  * consumer's producer is not running at normal speed.
  39  */
  40 #undef DEINTERLACE_ON_NOT_NORMAL_SPEED
  41
  42 /** This is not the ideal place for this, but it is needed by VDPAU as well.
  43  */
  44 pthread_mutex_t mlt_sdl_mutex = PTHREAD_MUTEX_INITIALIZER;
  45
  46 static void mlt_consumer_frame_render( mlt_listener listener, mlt_properties owner, mlt_service self, void **args );
  47 static void mlt_consumer_frame_show( mlt_listener listener, mlt_properties owner, mlt_service self, void **args );
  48 static void mlt_consumer_property_changed( mlt_properties owner, mlt_consumer self, char *name );
  49 static void apply_profile_properties( mlt_consumer self, mlt_profile profile, mlt_properties properties );
  50 static void on_consumer_frame_show( mlt_properties owner, mlt_consumer self, mlt_frame frame );
  51
  52 /** Initialize a consumer service.
  53  *
  54  * \public \memberof mlt_consumer_s
  55  * \param self the consumer to initialize
  56  * \param child a pointer to the object for the subclass
  57  * \param profile the \p mlt_profile_s to use (optional but recommended,
  58  * uses the environment variable MLT if self is NULL)
  59  * \return true if there was an error
  60  */
  61
  62 int mlt_consumer_init( mlt_consumer self, void *child, mlt_profile profile )
  63 {
  64         int error = 0;
  65         memset( self, 0, sizeof( struct mlt_consumer_s ) );
  66         self->child = child;
  67         error = mlt_service_init( &self->parent, self );
  68         if ( error == 0 )
  69         {
  70                 // Get the properties from the service
  71                 mlt_properties properties = MLT_SERVICE_PROPERTIES( &self->parent );
  72
  73                 // Apply profile to properties
  74                 if ( profile == NULL )
  75                 {
  76                         // Normally the application creates the profile and controls its lifetime
  77                         // This is the fallback exception handling
  78                         profile = mlt_profile_init( NULL );
  79                         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
  80                         mlt_properties_set_data( properties, "_profile", profile, 0, (mlt_destructor)mlt_profile_close, NULL );
  81                 }
  82                 apply_profile_properties( self, profile, properties );
  83
  84                 // Default rescaler for all consumers
  85                 mlt_properties_set( properties, "rescale", "bilinear" );
  86
  87                 // Default read ahead buffer size
  88                 mlt_properties_set_int( properties, "buffer", 25 );
  89
  90                 // Default audio frequency and channels
  91                 mlt_properties_set_int( properties, "frequency", 48000 );
  92                 mlt_properties_set_int( properties, "channels", 2 );
  93
  94                 // Default of all consumers is real time
  95                 mlt_properties_set_int( properties, "real_time", 1 );
  96
  97                 // Default to environment test card
  98                 mlt_properties_set( properties, "test_card", mlt_environment( "MLT_TEST_CARD" ) );
  99
 100                 // Hmm - default all consumers to yuv422 :-/
 101                 self->format = mlt_image_yuv422;
 102
 103                 mlt_events_register( properties, "consumer-frame-show", ( mlt_transmitter )mlt_consumer_frame_show );
 104                 mlt_events_register( properties, "consumer-frame-render", ( mlt_transmitter )mlt_consumer_frame_render );
 105                 mlt_events_register( properties, "consumer-stopped", NULL );
 106                 mlt_events_listen( properties, self, "consumer-frame-show", ( mlt_listener )on_consumer_frame_show );
 107
 108                 // Register a property-changed listener to handle the profile property -
 109                 // subsequent properties can override the profile
 110                 self->event_listener = mlt_events_listen( properties, self, "property-changed", ( mlt_listener )mlt_consumer_property_changed );
 111
 112                 // Create the push mutex and condition
 113                 pthread_mutex_init( &self->put_mutex, NULL );
 114                 pthread_cond_init( &self->put_cond, NULL );
 115
 116         }
 117         return error;
 118 }
 119
 120 /** Convert the profile into properties on the consumer.
 121  *
 122  * \private \memberof mlt_consumer_s
 123  * \param self a consumer
 124  * \param profile a profile
 125  * \param properties a properties list (typically, the consumer's)
 126  */
 127
 128 static void apply_profile_properties( mlt_consumer self, mlt_profile profile, mlt_properties properties )
 129 {
 130         mlt_event_block( self->event_listener );
 131         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 132         mlt_properties_set_int( properties, "frame_rate_num", profile->frame_rate_num );
 133         mlt_properties_set_int( properties, "frame_rate_den", profile->frame_rate_den );
 134         mlt_properties_set_int( properties, "width", profile->width );
 135         mlt_properties_set_int( properties, "height", profile->height );
 136         mlt_properties_set_int( properties, "progressive", profile->progressive );
 137         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 138         mlt_properties_set_int( properties, "sample_aspect_num", profile->sample_aspect_num );
 139         mlt_properties_set_int( properties, "sample_aspect_den", profile->sample_aspect_den );
 140         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 141         mlt_properties_set_int( properties, "display_aspect_num", profile->display_aspect_num );
 142         mlt_properties_set_int( properties, "display_aspect_num", profile->display_aspect_num );
 143         mlt_properties_set_int( properties, "colorspace", profile->colorspace );
 144         mlt_event_unblock( self->event_listener );
 145 }
 146
 147 /** The property-changed event listener
 148  *
 149  * \private \memberof mlt_consumer_s
 150  * \param owner the events object
 151  * \param self the consumer
 152  * \param name the name of the property that changed
 153  */
 154
 155 static void mlt_consumer_property_changed( mlt_properties owner, mlt_consumer self, char *name )
 156 {
 157         if ( !strcmp( name, "profile" ) )
 158         {
 159                 // Get the properies
 160                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 161
 162                 // Get the current profile
 163                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 164
 165                 // Load the new profile
 166                 mlt_profile new_profile = mlt_profile_init( mlt_properties_get( properties, name ) );
 167
 168                 if ( new_profile )
 169                 {
 170                         // Copy the profile
 171                         if ( profile != NULL )
 172                         {
 173                                 free( profile->description );
 174                                 memcpy( profile, new_profile, sizeof( struct mlt_profile_s ) );
 175                                 profile->description = strdup( new_profile->description );
 176                                 mlt_profile_close( new_profile );
 177                         }
 178                         else
 179                         {
 180                                 profile = new_profile;
 181                         }
 182
 183                         // Apply to properties
 184                         apply_profile_properties( self, profile, properties );
 185                 }
 186         }
 187         else if ( !strcmp( name, "frame_rate_num" ) )
 188         {
 189                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 190                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 191                 if ( profile )
 192                 {
 193                         profile->frame_rate_num = mlt_properties_get_int( properties, "frame_rate_num" );
 194                         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 195                 }
 196         }
 197         else if ( !strcmp( name, "frame_rate_den" ) )
 198         {
 199                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 200                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 201                 if ( profile )
 202                 {
 203                         profile->frame_rate_den = mlt_properties_get_int( properties, "frame_rate_den" );
 204                         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 205                 }
 206         }
 207         else if ( !strcmp( name, "width" ) )
 208         {
 209                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 210                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 211                 if ( profile )
 212                         profile->width = mlt_properties_get_int( properties, "width" );
 213         }
 214         else if ( !strcmp( name, "height" ) )
 215         {
 216                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 217                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 218                 if ( profile )
 219                         profile->height = mlt_properties_get_int( properties, "height" );
 220         }
 221         else if ( !strcmp( name, "progressive" ) )
 222         {
 223                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 224                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 225                 if ( profile )
 226                         profile->progressive = mlt_properties_get_int( properties, "progressive" );
 227         }
 228         else if ( !strcmp( name, "sample_aspect_num" ) )
 229         {
 230                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 231                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 232                 profile->sample_aspect_num = mlt_properties_get_int( properties, "sample_aspect_num" );
 233                 if ( profile )
 234                         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 235         }
 236         else if ( !strcmp( name, "sample_aspect_den" ) )
 237         {
 238                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 239                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 240                 profile->sample_aspect_den = mlt_properties_get_int( properties, "sample_aspect_den" );
 241                 if ( profile )
 242                         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 243         }
 244         else if ( !strcmp( name, "display_aspect_num" ) )
 245         {
 246                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 247                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 248                 if ( profile )
 249                 {
 250                         profile->display_aspect_num = mlt_properties_get_int( properties, "display_aspect_num" );
 251                         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 252                 }
 253         }
 254         else if ( !strcmp( name, "display_aspect_den" ) )
 255         {
 256                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 257                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 258                 if ( profile )
 259                 {
 260                         profile->display_aspect_den = mlt_properties_get_int( properties, "display_aspect_den" );
 261                         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 262                 }
 263         }
 264         else if ( !strcmp( name, "colorspace" ) )
 265         {
 266                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 267                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 268                 if ( profile )
 269                         profile->colorspace = mlt_properties_get_int( properties, "colorspace" );
 270         }
 271 }
 272
 273 /** The transmitter for the consumer-frame-show event
 274  *
 275  * Invokes the listener.
 276  *
 277  * \private \memberof mlt_consumer_s
 278  * \param listener a function pointer that will be invoked
 279  * \param owner the events object that will be passed to \p listener
 280  * \param self  a service that will be passed to \p listener
 281  * \param args an array of pointers - the first entry is passed as a string to \p listener
 282  */
 283
 284 static void mlt_consumer_frame_show( mlt_listener listener, mlt_properties owner, mlt_service self, void **args )
 285 {
 286         if ( listener != NULL )
 287                 listener( owner, self, ( mlt_frame )args[ 0 ] );
 288 }
 289
 290 /** The transmitter for the consumer-frame-render event
 291  *
 292  * Invokes the listener.
 293  *
 294  * \private \memberof mlt_consumer_s
 295  * \param listener a function pointer that will be invoked
 296  * \param owner the events object that will be passed to \p listener
 297  * \param self  a service that will be passed to \p listener
 298  * \param args an array of pointers - the first entry is passed as a string to \p listener
 299  */
 300
 301 static void mlt_consumer_frame_render( mlt_listener listener, mlt_properties owner, mlt_service self, void **args )
 302 {
 303         if ( listener != NULL )
 304                 listener( owner, self, ( mlt_frame )args[ 0 ] );
 305 }
 306
 307 /** A listener on the consumer-frame-show event
 308  *
 309  * Saves the position of the frame shown.
 310  *
 311  * \private \memberof mlt_consumer_s
 312  * \param owner the events object
 313  * \param consumer the consumer on which this event occurred
 314  * \param frame the frame that was shown
 315  */
 316
 317 static void on_consumer_frame_show( mlt_properties owner, mlt_consumer consumer, mlt_frame frame )
 318 {
 319         if ( frame )
 320                 consumer->position = mlt_frame_get_position( frame );
 321 }
 322
 323 /** Create a new consumer.
 324  *
 325  * \public \memberof mlt_consumer_s
 326  * \param profile a profile (optional, but recommended)
 327  * \return a new consumer
 328  */
 329
 330 mlt_consumer mlt_consumer_new( mlt_profile profile )
 331 {
 332         // Create the memory for the structure
 333         mlt_consumer self = malloc( sizeof( struct mlt_consumer_s ) );
 334
 335         // Initialise it
 336         if ( self != NULL )
 337                 mlt_consumer_init( self, NULL, profile );
 338
 339         // Return it
 340         return self;
 341 }
 342
 343 /** Get the parent service object.
 344  *
 345  * \public \memberof mlt_consumer_s
 346  * \param self a consumer
 347  * \return the parent service class
 348  * \see MLT_CONSUMER_SERVICE
 349  */
 350
 351 mlt_service mlt_consumer_service( mlt_consumer self )
 352 {
 353         return self != NULL ? &self->parent : NULL;
 354 }
 355
 356 /** Get the consumer properties.
 357  *
 358  * \public \memberof mlt_consumer_s
 359  * \param self a consumer
 360  * \return the consumer's properties list
 361  * \see MLT_CONSUMER_PROPERTIES
 362  */
 363
 364 mlt_properties mlt_consumer_properties( mlt_consumer self )
 365 {
 366         return self != NULL ? MLT_SERVICE_PROPERTIES( &self->parent ) : NULL;
 367 }
 368
 369 /** Connect the consumer to the producer.
 370  *
 371  * \public \memberof mlt_consumer_s
 372  * \param self a consumer
 373  * \param producer a producer
 374  * \return > 0 warning, == 0 success, < 0 serious error,
 375  *         1 = this service does not accept input,
 376  *         2 = the producer is invalid,
 377  *         3 = the producer is already registered with this consumer
 378  */
 379
 380 int mlt_consumer_connect( mlt_consumer self, mlt_service producer )
 381 {
 382         return mlt_service_connect_producer( &self->parent, producer, 0 );
 383 }
 384
 385 /** Start the consumer.
 386  *
 387  * \public \memberof mlt_consumer_s
 388  * \param self a consumer
 389  * \return true if there was an error
 390  */
 391
 392 int mlt_consumer_start( mlt_consumer self )
 393 {
 394         // Stop listening to the property-changed event
 395         mlt_event_block( self->event_listener );
 396
 397         // Get the properies
 398         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 399
 400         // Determine if there's a test card producer
 401         char *test_card = mlt_properties_get( properties, "test_card" );
 402
 403         // Just to make sure nothing is hanging around...
 404         self->put = NULL;
 405         self->put_active = 1;
 406
 407         // Deal with it now.
 408         if ( test_card != NULL )
 409         {
 410                 if ( mlt_properties_get_data( properties, "test_card_producer", NULL ) == NULL )
 411                 {
 412                         // Create a test card producer
 413                         mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 414                         mlt_producer producer = mlt_factory_producer( profile, NULL, test_card );
 415
 416                         // Do we have a producer
 417                         if ( producer != NULL )
 418                         {
 419                                 // Test card should loop I guess...
 420                                 mlt_properties_set( MLT_PRODUCER_PROPERTIES( producer ), "eof", "loop" );
 421                                 //mlt_producer_set_speed( producer, 0 );
 422                                 //mlt_producer_set_in_and_out( producer, 0, 0 );
 423
 424                                 // Set the test card on the consumer
 425                                 mlt_properties_set_data( properties, "test_card_producer", producer, 0, ( mlt_destructor )mlt_producer_close, NULL );
 426                         }
 427                 }
 428         }
 429         else
 430         {
 431                 // Allow the hash table to speed things up
 432                 mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
 433         }
 434
 435         // Set the frame duration in microseconds for the frame-dropping heuristic
 436         int frame_duration = 1000000 / mlt_properties_get_int( properties, "frame_rate_num" ) *
 437                         mlt_properties_get_int( properties, "frame_rate_den" );
 438         mlt_properties_set_int( properties, "frame_duration", frame_duration );
 439
 440         // Check and run an ante command
 441         if ( mlt_properties_get( properties, "ante" ) )
 442                 if ( system( mlt_properties_get( properties, "ante" ) ) == -1 )
 443                         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_ERROR, "system(%s) failed!\n", mlt_properties_get( properties, "ante" ) );
 444
 445         // Set the real_time preference
 446         self->real_time = mlt_properties_get_int( properties, "real_time" );
 447
 448         // For worker threads implementation, buffer must be at least # threads
 449         if ( abs( self->real_time ) > 1 && mlt_properties_get_int( properties, "buffer" ) <= abs( self->real_time ) )
 450                 mlt_properties_set_int( properties, "buffer", abs( self->real_time ) + 1 );
 451
 452         // Start the service
 453         if ( self->start != NULL )
 454                 return self->start( self );
 455
 456         return 0;
 457 }
 458
 459 /** An alternative method to feed frames into the consumer.
 460  *
 461  * Only valid if the consumer itself is not connected.
 462  *
 463  * \public \memberof mlt_consumer_s
 464  * \param self a consumer
 465  * \param frame a frame
 466  * \return true (ignore self for now)
 467  */
 468
 469 int mlt_consumer_put_frame( mlt_consumer self, mlt_frame frame )
 470 {
 471         int error = 1;
 472
 473         // Get the service assoicated to the consumer
 474         mlt_service service = MLT_CONSUMER_SERVICE( self );
 475
 476         if ( mlt_service_producer( service ) == NULL )
 477         {
 478                 struct timeval now;
 479                 struct timespec tm;
 480                 pthread_mutex_lock( &self->put_mutex );
 481                 while ( self->put_active && self->put != NULL )
 482                 {
 483                         gettimeofday( &now, NULL );
 484                         tm.tv_sec = now.tv_sec + 1;
 485                         tm.tv_nsec = now.tv_usec * 1000;
 486                         pthread_cond_timedwait( &self->put_cond, &self->put_mutex, &tm );
 487                 }
 488                 if ( self->put_active && self->put == NULL )
 489                         self->put = frame;
 490                 else
 491                         mlt_frame_close( frame );
 492                 pthread_cond_broadcast( &self->put_cond );
 493                 pthread_mutex_unlock( &self->put_mutex );
 494         }
 495         else
 496         {
 497                 mlt_frame_close( frame );
 498         }
 499
 500         return error;
 501 }
 502
 503 /** Protected method for consumer to get frames from connected service
 504  *
 505  * \public \memberof mlt_consumer_s
 506  * \param self a consumer
 507  * \return a frame
 508  */
 509
 510 mlt_frame mlt_consumer_get_frame( mlt_consumer self )
 511 {
 512         // Frame to return
 513         mlt_frame frame = NULL;
 514
 515         // Get the service assoicated to the consumer
 516         mlt_service service = MLT_CONSUMER_SERVICE( self );
 517
 518         // Get the consumer properties
 519         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 520
 521         // Get the frame
 522         if ( mlt_service_producer( service ) == NULL && mlt_properties_get_int( properties, "put_mode" ) )
 523         {
 524                 struct timeval now;
 525                 struct timespec tm;
 526                 pthread_mutex_lock( &self->put_mutex );
 527                 while ( self->put_active && self->put == NULL )
 528                 {
 529                         gettimeofday( &now, NULL );
 530                         tm.tv_sec = now.tv_sec + 1;
 531                         tm.tv_nsec = now.tv_usec * 1000;
 532                         pthread_cond_timedwait( &self->put_cond, &self->put_mutex, &tm );
 533                 }
 534                 frame = self->put;
 535                 self->put = NULL;
 536                 pthread_cond_broadcast( &self->put_cond );
 537                 pthread_mutex_unlock( &self->put_mutex );
 538                 if ( frame != NULL )
 539                         mlt_service_apply_filters( service, frame, 0 );
 540         }
 541         else if ( mlt_service_producer( service ) != NULL )
 542         {
 543                 mlt_service_get_frame( service, &frame, 0 );
 544         }
 545         else
 546         {
 547                 frame = mlt_frame_init( service );
 548         }
 549
 550         if ( frame != NULL )
 551         {
 552                 // Get the frame properties
 553                 mlt_properties frame_properties = MLT_FRAME_PROPERTIES( frame );
 554
 555                 // Get the test card producer
 556                 mlt_producer test_card = mlt_properties_get_data( properties, "test_card_producer", NULL );
 557
 558                 // Attach the test frame producer to it.
 559                 if ( test_card != NULL )
 560                         mlt_properties_set_data( frame_properties, "test_card_producer", test_card, 0, NULL, NULL );
 561
 562                 // Attach the rescale property
 563                 mlt_properties_set( frame_properties, "rescale.interp", mlt_properties_get( properties, "rescale" ) );
 564
 565                 // Aspect ratio and other jiggery pokery
 566                 mlt_properties_set_double( frame_properties, "consumer_aspect_ratio", mlt_properties_get_double( properties, "aspect_ratio" ) );
 567                 mlt_properties_set_int( frame_properties, "consumer_deinterlace", mlt_properties_get_int( properties, "progressive" ) | mlt_properties_get_int( properties, "deinterlace" ) );
 568                 mlt_properties_set( frame_properties, "deinterlace_method", mlt_properties_get( properties, "deinterlace_method" ) );
 569         }
 570
 571         // Return the frame
 572         return frame;
 573 }
 574
 575 /** Compute the time difference between now and a time value.
 576  *
 577  * \private \memberof mlt_consumer_s
 578  * \param time1 a time value to be compared against now
 579  * \return the difference in microseconds
 580  */
 581
 582 static inline long time_difference( struct timeval *time1 )
 583 {
 584         struct timeval time2;
 585         time2.tv_sec = time1->tv_sec;
 586         time2.tv_usec = time1->tv_usec;
 587         gettimeofday( time1, NULL );
 588         return time1->tv_sec * 1000000 + time1->tv_usec - time2.tv_sec * 1000000 - time2.tv_usec;
 589 }
 590
 591 /** The thread procedure for asynchronously pulling frames through the service
 592  * network connected to a consumer.
 593  *
 594  * \private \memberof mlt_consumer_s
 595  * \param arg a consumer
 596  */
 597
 598 static void *consumer_read_ahead_thread( void *arg )
 599 {
 600         // The argument is the consumer
 601         mlt_consumer self = arg;
 602
 603         // Get the properties of the consumer
 604         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 605
 606         // Get the width and height
 607         int width = mlt_properties_get_int( properties, "width" );
 608         int height = mlt_properties_get_int( properties, "height" );
 609
 610         // See if video is turned off
 611         int video_off = mlt_properties_get_int( properties, "video_off" );
 612         int preview_off = mlt_properties_get_int( properties, "preview_off" );
 613         int preview_format = mlt_properties_get_int( properties, "preview_format" );
 614
 615         // Get the audio settings
 616         mlt_audio_format afmt = mlt_audio_s16;
 617         int counter = 0;
 618         double fps = mlt_properties_get_double( properties, "fps" );
 619         int channels = mlt_properties_get_int( properties, "channels" );
 620         int frequency = mlt_properties_get_int( properties, "frequency" );
 621         int samples = 0;
 622         void *audio = NULL;
 623
 624         // See if audio is turned off
 625         int audio_off = mlt_properties_get_int( properties, "audio_off" );
 626
 627         // Get the maximum size of the buffer
 628         int buffer = mlt_properties_get_int( properties, "buffer" ) + 1;
 629
 630         // General frame variable
 631         mlt_frame frame = NULL;
 632         uint8_t *image = NULL;
 633
 634         // Time structures
 635         struct timeval ante;
 636
 637         // Average time for get_frame and get_image
 638         int count = 1;
 639         int skipped = 0;
 640         int64_t time_wait = 0;
 641         int64_t time_frame = 0;
 642         int64_t time_process = 0;
 643         int skip_next = 0;
 644
 645         if ( preview_off && preview_format != 0 )
 646                 self->format = preview_format;
 647
 648         // Get the first frame
 649         frame = mlt_consumer_get_frame( self );
 650
 651         // Get the image of the first frame
 652         if ( !video_off )
 653         {
 654                 mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 655                 mlt_frame_get_image( frame, &image, &self->format, &width, &height, 0 );
 656         }
 657
 658         if ( !audio_off )
 659         {
 660                 samples = mlt_sample_calculator( fps, frequency, counter++ );
 661                 mlt_frame_get_audio( frame, &audio, &afmt, &frequency, &channels, &samples );
 662         }
 663
 664         // Mark as rendered
 665         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 666
 667         // Get the starting time (can ignore the times above)
 668         gettimeofday( &ante, NULL );
 669
 670         // Continue to read ahead
 671         while ( self->ahead )
 672         {
 673                 // Fetch width/height again
 674                 width = mlt_properties_get_int( properties, "width" );
 675                 height = mlt_properties_get_int( properties, "height" );
 676
 677                 // Put the current frame into the queue
 678                 pthread_mutex_lock( &self->queue_mutex );
 679                 while( self->ahead && mlt_deque_count( self->queue ) >= buffer )
 680                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
 681                 mlt_deque_push_back( self->queue, frame );
 682                 pthread_cond_broadcast( &self->queue_cond );
 683                 pthread_mutex_unlock( &self->queue_mutex );
 684
 685                 time_wait += time_difference( &ante );
 686
 687                 // Get the next frame
 688                 frame = mlt_consumer_get_frame( self );
 689                 time_frame += time_difference( &ante );
 690
 691                 // If there's no frame, we're probably stopped...
 692                 if ( frame == NULL )
 693                         continue;
 694
 695                 // Increment the count
 696                 count ++;
 697
 698                 // All non normal playback frames should be shown
 699                 if ( mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "_speed" ) != 1 )
 700                 {
 701 #ifdef DEINTERLACE_ON_NOT_NORMAL_SPEED
 702                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "consumer_deinterlace", 1 );
 703 #endif
 704                         skipped = 0;
 705                         time_frame = 0;
 706                         time_process = 0;
 707                         time_wait = 0;
 708                         count = 1;
 709                         skip_next = 0;
 710                 }
 711
 712                 // Get the image
 713                 if ( !skip_next || self->real_time == -1 )
 714                 {
 715                         // Get the image, mark as rendered and time it
 716                         if ( !video_off )
 717                         {
 718                                 mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 719                                 mlt_frame_get_image( frame, &image, &self->format, &width, &height, 0 );
 720                         }
 721                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 722                 }
 723                 else
 724                 {
 725                         // Increment the number of sequentially skipped frames
 726                         skipped ++;
 727                         skip_next = 0;
 728
 729                         // If we've reached an unacceptable level, reset everything
 730                         if ( skipped > fps * 2 )
 731                         {
 732                                 skipped = 0;
 733                                 time_frame = 0;
 734                                 time_process = 0;
 735                                 time_wait = 0;
 736                                 count = 1;
 737                         }
 738                 }
 739
 740                 // Always process audio
 741                 if ( !audio_off )
 742                 {
 743                         samples = mlt_sample_calculator( fps, frequency, counter++ );
 744                         mlt_frame_get_audio( frame, &audio, &afmt, &frequency, &channels, &samples );
 745                 }
 746
 747                 // Increment the time take for self frame
 748                 time_process += time_difference( &ante );
 749
 750                 // Determine if the next frame should be skipped
 751                 if ( mlt_deque_count( self->queue ) <= 5 )
 752                 {
 753                         int frame_duration = mlt_properties_get_int( properties, "frame_duration" );
 754                         if ( ( ( time_wait + time_frame + time_process ) / count ) > frame_duration )
 755                                 skip_next = 1;
 756                 }
 757         }
 758
 759         // Remove the last frame
 760         mlt_frame_close( frame );
 761
 762         return NULL;
 763 }
 764
 765 /** Locate the first unprocessed frame in the queue.
 766  *
 767  * When playing with realtime behavior, we do not use the true head, but
 768  * rather an adjusted process_head. The process_head is adjusted based on
 769  * the rate of frame-dropping or recovery from frame-dropping. The idea is
 770  * that as the level of frame-dropping increases to move the process_head
 771  * closer to the tail because the frames are not completing processing prior
 772  * to their playout! Then, as frames are not dropped the process_head moves
 773  * back closer to the head of the queue so that worker threads can work
 774  * ahead of the playout point (queue head).
 775  *
 776  * \private \memberof mlt_consumer_s
 777  * \param self a consumer
 778  * \return an index into the queue
 779  */
 780
 781 static inline int first_unprocessed_frame( mlt_consumer self )
 782 {
 783         int index = self->real_time <= 0 ? 0 : self->process_head;
 784         while ( index < mlt_deque_count( self->queue ) && MLT_FRAME( mlt_deque_peek( self->queue, index ) )->is_processing )
 785                 index++;
 786         return index;
 787 }
 788
 789 /** The worker thread procedure for parallel processing frames.
 790  *
 791  * \private \memberof mlt_consumer_s
 792  * \param arg a consumer
 793  */
 794
 795 static void *consumer_worker_thread( void *arg )
 796 {
 797         // The argument is the consumer
 798         mlt_consumer self = arg;
 799
 800         // Get the properties of the consumer
 801         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 802
 803         // Get the width and height
 804         int width = mlt_properties_get_int( properties, "width" );
 805         int height = mlt_properties_get_int( properties, "height" );
 806         mlt_image_format format = self->format;
 807
 808         // See if video is turned off
 809         int video_off = mlt_properties_get_int( properties, "video_off" );
 810         int preview_off = mlt_properties_get_int( properties, "preview_off" );
 811         int preview_format = mlt_properties_get_int( properties, "preview_format" );
 812
 813         // General frame variable
 814         mlt_frame frame = NULL;
 815         uint8_t *image = NULL;
 816
 817         if ( preview_off && preview_format != 0 )
 818                 format = preview_format;
 819
 820         // Continue to read ahead
 821         while ( self->ahead )
 822         {
 823                 // Get the next unprocessed frame from the work queue
 824                 pthread_mutex_lock( &self->queue_mutex );
 825                 int index = first_unprocessed_frame( self );
 826                 while ( self->ahead && index >= mlt_deque_count( self->queue ) )
 827                 {
 828                         mlt_log_debug( MLT_CONSUMER_SERVICE(self), "waiting in worker index = %d queue count = %d\n",
 829                                 index, mlt_deque_count( self->queue ) );
 830                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
 831                         index = first_unprocessed_frame( self );
 832                 }
 833
 834                 // Mark the frame for processing
 835                 frame = mlt_deque_peek( self->queue, index );
 836                 if ( frame )
 837                 {
 838                         mlt_log_debug( MLT_CONSUMER_SERVICE(self), "worker processing index = %d frame %d queue count = %d\n",
 839                                 index, mlt_frame_get_position(frame), mlt_deque_count( self->queue ) );
 840                         frame->is_processing = 1;
 841                         mlt_properties_inc_ref( MLT_FRAME_PROPERTIES( frame ) );
 842                 }
 843                 pthread_mutex_unlock( &self->queue_mutex );
 844
 845                 // If there's no frame, we're probably stopped...
 846                 if ( frame == NULL )
 847                         continue;
 848
 849 #ifdef DEINTERLACE_ON_NOT_NORMAL_SPEED
 850                 // All non normal playback frames should be shown
 851                 if ( mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "_speed" ) != 1 )
 852                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "consumer_deinterlace", 1 );
 853 #endif
 854
 855                 // Get the image
 856                 if ( !video_off )
 857                 {
 858                         // Fetch width/height again
 859                         width = mlt_properties_get_int( properties, "width" );
 860                         height = mlt_properties_get_int( properties, "height" );
 861                         mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 862                         mlt_frame_get_image( frame, &image, &format, &width, &height, 0 );
 863                 }
 864                 mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 865                 mlt_frame_close( frame );
 866
 867                 // Tell a waiting thread (non-realtime main consumer thread) that we are done.
 868                 pthread_mutex_lock( &self->done_mutex );
 869                 pthread_cond_broadcast( &self->done_cond );
 870                 pthread_mutex_unlock( &self->done_mutex );
 871         }
 872
 873         return NULL;
 874 }
 875
 876 /** Start the read/render thread.
 877  *
 878  * \private \memberof mlt_consumer_s
 879  * \param self a consumer
 880  */
 881
 882 static void consumer_read_ahead_start( mlt_consumer self )
 883 {
 884         // We're running now
 885         self->ahead = 1;
 886
 887         // Create the frame queue
 888         self->queue = mlt_deque_init( );
 889
 890         // Create the queue mutex
 891         pthread_mutex_init( &self->queue_mutex, NULL );
 892
 893         // Create the condition
 894         pthread_cond_init( &self->queue_cond, NULL );
 895
 896         // Create the read ahead
 897         if ( mlt_properties_get( MLT_CONSUMER_PROPERTIES( self ), "priority" ) )
 898         {
 899                 struct sched_param priority;
 900                 priority.sched_priority = mlt_properties_get_int( MLT_CONSUMER_PROPERTIES( self ), "priority" );
 901                 pthread_attr_t thread_attributes;
 902                 pthread_attr_init( &thread_attributes );
 903                 pthread_attr_setschedpolicy( &thread_attributes, SCHED_OTHER );
 904                 pthread_attr_setschedparam( &thread_attributes, &priority );
 905                 pthread_attr_setinheritsched( &thread_attributes, PTHREAD_EXPLICIT_SCHED );
 906                 pthread_attr_setscope( &thread_attributes, PTHREAD_SCOPE_SYSTEM );
 907                 if ( pthread_create( &self->ahead_thread, &thread_attributes, consumer_read_ahead_thread, self ) < 0 )
 908                         pthread_create( &self->ahead_thread, NULL, consumer_read_ahead_thread, self );
 909                 pthread_attr_destroy( &thread_attributes );
 910         }
 911         else
 912         {
 913                 pthread_create( &self->ahead_thread, NULL, consumer_read_ahead_thread, self );
 914         }
 915         self->started = 1;
 916 }
 917
 918 /** Start the worker threads.
 919  *
 920  * \private \memberof mlt_consumer_s
 921  * \param self a consumer
 922  */
 923
 924 static void consumer_work_start( mlt_consumer self )
 925 {
 926         int n = abs( self->real_time );
 927         pthread_t *thread = calloc( 1, sizeof( pthread_t ) );
 928
 929         // We're running now
 930         self->ahead = 1;
 931
 932         // These keep track of the accelleration of frame dropping or recovery.
 933         self->consecutive_dropped = 0;
 934         self->consecutive_rendered = 0;
 935
 936         // This is the position in the queue from which to look for a frame to process.
 937         // If we always start from the head, then we may likely not complete processing
 938         // before the frame is played out.
 939         self->process_head = 0;
 940
 941         // Create the queues
 942         self->queue = mlt_deque_init();
 943         self->worker_threads = mlt_deque_init();
 944
 945         // Create the mutexes
 946         pthread_mutex_init( &self->queue_mutex, NULL );
 947         pthread_mutex_init( &self->done_mutex, NULL );
 948
 949         // Create the conditions
 950         pthread_cond_init( &self->queue_cond, NULL );
 951         pthread_cond_init( &self->done_cond, NULL );
 952
 953         // Create the read ahead
 954         if ( mlt_properties_get( MLT_CONSUMER_PROPERTIES( self ), "priority" ) )
 955         {
 956
 957                 struct sched_param priority;
 958                 pthread_attr_t thread_attributes;
 959
 960                 priority.sched_priority = mlt_properties_get_int( MLT_CONSUMER_PROPERTIES( self ), "priority" );
 961                 pthread_attr_init( &thread_attributes );
 962                 pthread_attr_setschedpolicy( &thread_attributes, SCHED_OTHER );
 963                 pthread_attr_setschedparam( &thread_attributes, &priority );
 964                 pthread_attr_setinheritsched( &thread_attributes, PTHREAD_EXPLICIT_SCHED );
 965                 pthread_attr_setscope( &thread_attributes, PTHREAD_SCOPE_SYSTEM );
 966
 967                 while ( n-- )
 968                 {
 969                         if ( pthread_create( thread, &thread_attributes, consumer_read_ahead_thread, self ) < 0 )
 970                                 if ( pthread_create( thread, NULL, consumer_read_ahead_thread, self ) == 0 )
 971                                         mlt_deque_push_back( self->worker_threads, thread );
 972                 }
 973                 pthread_attr_destroy( &thread_attributes );
 974         }
 975
 976         else
 977         {
 978                 while ( n-- )
 979                 {
 980                         if ( pthread_create( thread, NULL, consumer_worker_thread, self ) == 0 )
 981                                 mlt_deque_push_back( self->worker_threads, thread );
 982                 }
 983         }
 984         self->started = 1;
 985 }
 986
 987 /** Stop the read/render thread.
 988  *
 989  * \private \memberof mlt_consumer_s
 990  * \param self a consumer
 991  */
 992
 993 static void consumer_read_ahead_stop( mlt_consumer self )
 994 {
 995         // Make sure we're running
 996         if ( self->started )
 997         {
 998                 // Inform thread to stop
 999                 self->ahead = 0;
1000
1001                 // Broadcast to the condition in case it's waiting
1002                 pthread_mutex_lock( &self->queue_mutex );
1003                 pthread_cond_broadcast( &self->queue_cond );
1004                 pthread_mutex_unlock( &self->queue_mutex );
1005
1006                 // Broadcast to the put condition in case it's waiting
1007                 pthread_mutex_lock( &self->put_mutex );
1008                 pthread_cond_broadcast( &self->put_cond );
1009                 pthread_mutex_unlock( &self->put_mutex );
1010
1011                 // Join the thread
1012                 pthread_join( self->ahead_thread, NULL );
1013                 self->started = 0;
1014
1015                 // Destroy the frame queue mutex
1016                 pthread_mutex_destroy( &self->queue_mutex );
1017
1018                 // Destroy the condition
1019                 pthread_cond_destroy( &self->queue_cond );
1020
1021                 // Wipe the queue
1022                 while ( mlt_deque_count( self->queue ) )
1023                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1024
1025                 // Close the queue
1026                 mlt_deque_close( self->queue );
1027         }
1028 }
1029
1030 /** Stop the worker threads.
1031  *
1032  * \private \memberof mlt_consumer_s
1033  * \param self a consumer
1034  */
1035
1036 static void consumer_work_stop( mlt_consumer self )
1037 {
1038         // Make sure we're running
1039         if ( self->started )
1040         {
1041                 // Inform thread to stop
1042                 self->ahead = 0;
1043
1044                 // Broadcast to the queue condition in case it's waiting
1045                 pthread_mutex_lock( &self->queue_mutex );
1046                 pthread_cond_broadcast( &self->queue_cond );
1047                 pthread_mutex_unlock( &self->queue_mutex );
1048
1049                 // Broadcast to the put condition in case it's waiting
1050                 pthread_mutex_lock( &self->put_mutex );
1051                 pthread_cond_broadcast( &self->put_cond );
1052                 pthread_mutex_unlock( &self->put_mutex );
1053
1054                 // Broadcast to the done condition in case it's waiting
1055                 pthread_mutex_lock( &self->done_mutex );
1056                 pthread_cond_broadcast( &self->done_cond );
1057                 pthread_mutex_unlock( &self->done_mutex );
1058
1059                 // Join the threads
1060                 pthread_t *thread;
1061                 while ( ( thread = mlt_deque_pop_front( self->worker_threads ) ) )
1062                         pthread_join( *thread, NULL );
1063                 self->started = 0;
1064
1065                 // Destroy the mutexes
1066                 pthread_mutex_destroy( &self->queue_mutex );
1067                 pthread_mutex_destroy( &self->done_mutex );
1068
1069                 // Destroy the conditions
1070                 pthread_cond_destroy( &self->queue_cond );
1071                 pthread_cond_destroy( &self->done_cond );
1072
1073                 // Wipe the queues
1074                 while ( mlt_deque_count( self->queue ) )
1075                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1076
1077                 // Close the queues
1078                 mlt_deque_close( self->queue );
1079                 mlt_deque_close( self->worker_threads );
1080         }
1081 }
1082
1083 /** Flush the read/render thread's buffer.
1084  *
1085  * \public \memberof mlt_consumer_s
1086  * \param self a consumer
1087  */
1088
1089 void mlt_consumer_purge( mlt_consumer self )
1090 {
1091         if ( self->ahead )
1092         {
1093                 pthread_mutex_lock( &self->queue_mutex );
1094                 while ( mlt_deque_count( self->queue ) )
1095                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1096                 pthread_cond_broadcast( &self->queue_cond );
1097                 pthread_mutex_unlock( &self->queue_mutex );
1098         }
1099 }
1100
1101 /** Use multiple worker threads and a work queue.
1102  */
1103
1104 static mlt_frame worker_get_frame( mlt_consumer self, mlt_properties properties )
1105 {
1106         // Frame to return
1107         mlt_frame frame = NULL;
1108
1109         int size = abs( self->real_time );
1110         int buffer = mlt_properties_get_int( properties, "buffer" );
1111         // This is a heuristic to determine a suitable minimum buffer size for the number of threads.
1112         int headroom = 2 + size * size;
1113         buffer = buffer < headroom ? headroom : buffer;
1114
1115         // Start worker threads if not already started.
1116         if ( ! self->ahead )
1117         {
1118                 int prefill = mlt_properties_get_int( properties, "prefill" );
1119                 prefill = prefill > 0 && prefill < buffer ? prefill : buffer;
1120
1121                 consumer_work_start( self );
1122
1123                 // Fill the work queue.
1124                 int i = buffer;
1125                 while ( self->ahead && i-- )
1126                 {
1127                         frame = mlt_consumer_get_frame( self );
1128                         if ( frame )
1129                         {
1130                                 pthread_mutex_lock( &self->queue_mutex );
1131                                 mlt_deque_push_back( self->queue, frame );
1132                                 pthread_cond_signal( &self->queue_cond );
1133                                 pthread_mutex_unlock( &self->queue_mutex );
1134                         }
1135                 }
1136
1137                 // Wait for prefill
1138                 while ( self->ahead && first_unprocessed_frame( self ) < prefill )
1139                 {
1140                         pthread_mutex_lock( &self->done_mutex );
1141                         pthread_cond_wait( &self->done_cond, &self->done_mutex );
1142                         pthread_mutex_unlock( &self->done_mutex );
1143                 }
1144                 self->process_head = size;
1145         }
1146
1147 //      mlt_log_verbose( MLT_CONSUMER_SERVICE(self), "size %d done count %d work count %d process_head %d\n",
1148 //              size, first_unprocessed_frame( self ), mlt_deque_count( self->queue ), self->process_head );
1149
1150         // Feed the work queue
1151         while ( self->ahead && mlt_deque_count( self->queue ) < buffer )
1152         {
1153                 frame = mlt_consumer_get_frame( self );
1154                 if ( ! frame )
1155                         return frame;
1156                 pthread_mutex_lock( &self->queue_mutex );
1157                 mlt_deque_push_back( self->queue, frame );
1158                 pthread_cond_signal( &self->queue_cond );
1159                 pthread_mutex_unlock( &self->queue_mutex );
1160         }
1161
1162         // Wait if not realtime.
1163         while( self->ahead && self->real_time < 0 &&
1164                ! mlt_properties_get_int( MLT_FRAME_PROPERTIES( MLT_FRAME( mlt_deque_peek_front( self->queue ) ) ), "rendered" ) )
1165         {
1166                 pthread_mutex_lock( &self->done_mutex );
1167                 pthread_cond_wait( &self->done_cond, &self->done_mutex );
1168                 pthread_mutex_unlock( &self->done_mutex );
1169         }
1170
1171         // Get the frame from the queue.
1172         pthread_mutex_lock( &self->queue_mutex );
1173         frame = mlt_deque_pop_front( self->queue );
1174         pthread_mutex_unlock( &self->queue_mutex );
1175
1176         // Adapt the worker process head to the runtime conditions.
1177         if ( self->real_time > 0 )
1178         {
1179                 if ( mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "rendered" ) )
1180                 {
1181                         self->consecutive_dropped = 0;
1182                         if ( self->process_head > size && self->consecutive_rendered >= self->process_head )
1183                                 self->process_head--;
1184                         else
1185                                 self->consecutive_rendered++;
1186                 }
1187                 else
1188                 {
1189                         self->consecutive_rendered = 0;
1190                         if ( self->process_head < buffer - size && self->consecutive_dropped > size )
1191                                 self->process_head++;
1192                         else
1193                                 self->consecutive_dropped++;
1194                 }
1195 //              mlt_log_verbose( MLT_CONSUMER_SERVICE(self), "dropped %d rendered %d process_head %d\n",
1196 //                      self->consecutive_dropped, self->consecutive_rendered, self->process_head );
1197         }
1198
1199         return frame;
1200 }
1201
1202 /** Get the next frame from the producer connected to a consumer.
1203  *
1204  * Typically, one uses this instead of \p mlt_consumer_get_frame to make
1205  * the asynchronous/real-time behavior configurable at runtime.
1206  * You should close the frame returned from this when you are done with it.
1207  *
1208  * \public \memberof mlt_consumer_s
1209  * \param self a consumer
1210  * \return a frame
1211  */
1212
1213 mlt_frame mlt_consumer_rt_frame( mlt_consumer self )
1214 {
1215         // Frame to return
1216         mlt_frame frame = NULL;
1217
1218         // Get the properties
1219         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
1220
1221         // Check if the user has requested real time or not
1222         if ( self->real_time > 1 || self->real_time < -1 )
1223         {
1224                 // see above
1225                 return worker_get_frame( self, properties );
1226         }
1227         else if ( self->real_time == 1 || self->real_time == -1 )
1228         {
1229                 int size = 1;
1230
1231                 // Is the read ahead running?
1232                 if ( self->ahead == 0 )
1233                 {
1234                         int buffer = mlt_properties_get_int( properties, "buffer" );
1235                         int prefill = mlt_properties_get_int( properties, "prefill" );
1236                         consumer_read_ahead_start( self );
1237                         if ( buffer > 1 )
1238                                 size = prefill > 0 && prefill < buffer ? prefill : buffer;
1239                 }
1240
1241                 // Get frame from queue
1242                 pthread_mutex_lock( &self->queue_mutex );
1243                 while( self->ahead && mlt_deque_count( self->queue ) < size )
1244                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
1245                 frame = mlt_deque_pop_front( self->queue );
1246                 pthread_cond_broadcast( &self->queue_cond );
1247                 pthread_mutex_unlock( &self->queue_mutex );
1248         }
1249         else // real_time == 0
1250         {
1251                 // Get the frame in non real time
1252                 frame = mlt_consumer_get_frame( self );
1253
1254                 // This isn't true, but from the consumers perspective it is
1255                 if ( frame != NULL )
1256                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
1257         }
1258
1259         return frame;
1260 }
1261
1262 /** Callback for the implementation to indicate a stopped condition.
1263  *
1264  * \public \memberof mlt_consumer_s
1265  * \param self a consumer
1266  */
1267
1268 void mlt_consumer_stopped( mlt_consumer self )
1269 {
1270         mlt_properties_set_int( MLT_CONSUMER_PROPERTIES( self ), "running", 0 );
1271         mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-stopped", NULL );
1272         mlt_event_unblock( self->event_listener );
1273 }
1274
1275 /** Stop the consumer.
1276  *
1277  * \public \memberof mlt_consumer_s
1278  * \param self a consumer
1279  * \return true if there was an error
1280  */
1281
1282 int mlt_consumer_stop( mlt_consumer self )
1283 {
1284         // Get the properies
1285         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
1286
1287         // Just in case...
1288         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping put waiting\n" );
1289         pthread_mutex_lock( &self->put_mutex );
1290         self->put_active = 0;
1291         pthread_cond_broadcast( &self->put_cond );
1292         pthread_mutex_unlock( &self->put_mutex );
1293
1294         // Stop the consumer
1295         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping consumer\n" );
1296
1297         // Cancel the read ahead threads
1298         self->ahead = 0;
1299         if ( self->started )
1300         {
1301                 // Unblock the consumer calling mlt_consumer_rt_frame
1302                 pthread_mutex_lock( &self->queue_mutex );
1303                 pthread_cond_broadcast( &self->queue_cond );
1304                 pthread_mutex_unlock( &self->queue_mutex );
1305         }
1306
1307         // Invoke the child callback
1308         if ( self->stop != NULL )
1309                 self->stop( self );
1310
1311         // Check if the user has requested real time or not and stop if necessary
1312         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping read_ahead\n" );
1313         if ( abs( self->real_time ) == 1 )
1314                 consumer_read_ahead_stop( self );
1315         else if ( abs( self->real_time ) > 1 )
1316                 consumer_work_stop( self );
1317
1318         // Kill the test card
1319         mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
1320
1321         // Check and run a post command
1322         if ( mlt_properties_get( properties, "post" ) )
1323                 if (system( mlt_properties_get( properties, "post" ) ) == -1 )
1324                         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_ERROR, "system(%s) failed!\n", mlt_properties_get( properties, "post" ) );
1325
1326         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopped\n" );
1327
1328         return 0;
1329 }
1330
1331 /** Determine if the consumer is stopped.
1332  *
1333  * \public \memberof mlt_consumer_s
1334  * \param self a consumer
1335  * \return true if the consumer is stopped
1336  */
1337
1338 int mlt_consumer_is_stopped( mlt_consumer self )
1339 {
1340         // Check if the consumer is stopped
1341         if ( self->is_stopped != NULL )
1342                 return self->is_stopped( self );
1343
1344         return 0;
1345 }
1346
1347 /** Close and destroy the consumer.
1348  *
1349  * \public \memberof mlt_consumer_s
1350  * \param self a consumer
1351  */
1352
1353 void mlt_consumer_close( mlt_consumer self )
1354 {
1355         if ( self != NULL && mlt_properties_dec_ref( MLT_CONSUMER_PROPERTIES( self ) ) <= 0 )
1356         {
1357                 // Get the childs close function
1358                 void ( *consumer_close )( ) = self->close;
1359
1360                 if ( consumer_close )
1361                 {
1362                         // Just in case...
1363                         //mlt_consumer_stop( self );
1364
1365                         self->close = NULL;
1366                         consumer_close( self );
1367                 }
1368                 else
1369                 {
1370                         // Make sure it only gets called once
1371                         self->parent.close = NULL;
1372
1373                         // Destroy the push mutex and condition
1374                         pthread_mutex_destroy( &self->put_mutex );
1375                         pthread_cond_destroy( &self->put_cond );
1376
1377                         mlt_service_close( &self->parent );
1378                 }
1379         }
1380 }
1381
1382 /** Get the position of the last frame shown.
1383  *
1384  * \public \memberof mlt_consumer_s
1385  * \param consumer a consumer
1386  * \return the position
1387  */
1388
1389 mlt_position mlt_consumer_position( mlt_consumer consumer )
1390 {
1391         return consumer->position;
1392 }
1393