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                 mlt_properties_set_int( properties, "drop_max", 5 );
  90
  91                 // Default audio frequency and channels
  92                 mlt_properties_set_int( properties, "frequency", 48000 );
  93                 mlt_properties_set_int( properties, "channels", 2 );
  94
  95                 // Default of all consumers is real time
  96                 mlt_properties_set_int( properties, "real_time", 1 );
  97
  98                 // Default to environment test card
  99                 mlt_properties_set( properties, "test_card", mlt_environment( "MLT_TEST_CARD" ) );
 100
 101                 // Hmm - default all consumers to yuv422 :-/
 102                 self->format = mlt_image_yuv422;
 103
 104                 mlt_events_register( properties, "consumer-frame-show", ( mlt_transmitter )mlt_consumer_frame_show );
 105                 mlt_events_register( properties, "consumer-frame-render", ( mlt_transmitter )mlt_consumer_frame_render );
 106                 mlt_events_register( properties, "consumer-stopped", NULL );
 107                 mlt_events_listen( properties, self, "consumer-frame-show", ( mlt_listener )on_consumer_frame_show );
 108
 109                 // Register a property-changed listener to handle the profile property -
 110                 // subsequent properties can override the profile
 111                 self->event_listener = mlt_events_listen( properties, self, "property-changed", ( mlt_listener )mlt_consumer_property_changed );
 112
 113                 // Create the push mutex and condition
 114                 pthread_mutex_init( &self->put_mutex, NULL );
 115                 pthread_cond_init( &self->put_cond, NULL );
 116
 117         }
 118         return error;
 119 }
 120
 121 /** Convert the profile into properties on the consumer.
 122  *
 123  * \private \memberof mlt_consumer_s
 124  * \param self a consumer
 125  * \param profile a profile
 126  * \param properties a properties list (typically, the consumer's)
 127  */
 128
 129 static void apply_profile_properties( mlt_consumer self, mlt_profile profile, mlt_properties properties )
 130 {
 131         mlt_event_block( self->event_listener );
 132         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 133         mlt_properties_set_int( properties, "frame_rate_num", profile->frame_rate_num );
 134         mlt_properties_set_int( properties, "frame_rate_den", profile->frame_rate_den );
 135         mlt_properties_set_int( properties, "width", profile->width );
 136         mlt_properties_set_int( properties, "height", profile->height );
 137         mlt_properties_set_int( properties, "progressive", profile->progressive );
 138         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 139         mlt_properties_set_int( properties, "sample_aspect_num", profile->sample_aspect_num );
 140         mlt_properties_set_int( properties, "sample_aspect_den", profile->sample_aspect_den );
 141         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 142         mlt_properties_set_int( properties, "display_aspect_num", profile->display_aspect_num );
 143         mlt_properties_set_int( properties, "display_aspect_num", profile->display_aspect_num );
 144         mlt_properties_set_int( properties, "colorspace", profile->colorspace );
 145         mlt_event_unblock( self->event_listener );
 146 }
 147
 148 /** The property-changed event listener
 149  *
 150  * \private \memberof mlt_consumer_s
 151  * \param owner the events object
 152  * \param self the consumer
 153  * \param name the name of the property that changed
 154  */
 155
 156 static void mlt_consumer_property_changed( mlt_properties owner, mlt_consumer self, char *name )
 157 {
 158         if ( !strcmp( name, "mlt_profile" ) )
 159         {
 160                 // Get the properies
 161                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 162
 163                 // Get the current profile
 164                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 165
 166                 // Load the new profile
 167                 mlt_profile new_profile = mlt_profile_init( mlt_properties_get( properties, name ) );
 168
 169                 if ( new_profile )
 170                 {
 171                         // Copy the profile
 172                         if ( profile != NULL )
 173                         {
 174                                 free( profile->description );
 175                                 memcpy( profile, new_profile, sizeof( struct mlt_profile_s ) );
 176                                 profile->description = strdup( new_profile->description );
 177                                 mlt_profile_close( new_profile );
 178                         }
 179                         else
 180                         {
 181                                 profile = new_profile;
 182                         }
 183
 184                         // Apply to properties
 185                         apply_profile_properties( self, profile, properties );
 186                 }
 187         }
 188         else if ( !strcmp( name, "frame_rate_num" ) )
 189         {
 190                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 191                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 192                 if ( profile )
 193                 {
 194                         profile->frame_rate_num = mlt_properties_get_int( properties, "frame_rate_num" );
 195                         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 196                 }
 197         }
 198         else if ( !strcmp( name, "frame_rate_den" ) )
 199         {
 200                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 201                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 202                 if ( profile )
 203                 {
 204                         profile->frame_rate_den = mlt_properties_get_int( properties, "frame_rate_den" );
 205                         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 206                 }
 207         }
 208         else if ( !strcmp( name, "width" ) )
 209         {
 210                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 211                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 212                 if ( profile )
 213                         profile->width = mlt_properties_get_int( properties, "width" );
 214         }
 215         else if ( !strcmp( name, "height" ) )
 216         {
 217                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 218                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 219                 if ( profile )
 220                         profile->height = mlt_properties_get_int( properties, "height" );
 221         }
 222         else if ( !strcmp( name, "progressive" ) )
 223         {
 224                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 225                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 226                 if ( profile )
 227                         profile->progressive = mlt_properties_get_int( properties, "progressive" );
 228         }
 229         else if ( !strcmp( name, "sample_aspect_num" ) )
 230         {
 231                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 232                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 233                 profile->sample_aspect_num = mlt_properties_get_int( properties, "sample_aspect_num" );
 234                 if ( profile )
 235                         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 236         }
 237         else if ( !strcmp( name, "sample_aspect_den" ) )
 238         {
 239                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 240                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 241                 profile->sample_aspect_den = mlt_properties_get_int( properties, "sample_aspect_den" );
 242                 if ( profile )
 243                         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 244         }
 245         else if ( !strcmp( name, "display_aspect_num" ) )
 246         {
 247                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 248                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 249                 if ( profile )
 250                 {
 251                         profile->display_aspect_num = mlt_properties_get_int( properties, "display_aspect_num" );
 252                         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 253                 }
 254         }
 255         else if ( !strcmp( name, "display_aspect_den" ) )
 256         {
 257                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 258                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 259                 if ( profile )
 260                 {
 261                         profile->display_aspect_den = mlt_properties_get_int( properties, "display_aspect_den" );
 262                         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 263                 }
 264         }
 265         else if ( !strcmp( name, "colorspace" ) )
 266         {
 267                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 268                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 269                 if ( profile )
 270                         profile->colorspace = mlt_properties_get_int( properties, "colorspace" );
 271         }
 272 }
 273
 274 /** The transmitter for the consumer-frame-show event
 275  *
 276  * Invokes the listener.
 277  *
 278  * \private \memberof mlt_consumer_s
 279  * \param listener a function pointer that will be invoked
 280  * \param owner the events object that will be passed to \p listener
 281  * \param self  a service that will be passed to \p listener
 282  * \param args an array of pointers - the first entry is passed as a string to \p listener
 283  */
 284
 285 static void mlt_consumer_frame_show( mlt_listener listener, mlt_properties owner, mlt_service self, void **args )
 286 {
 287         if ( listener != NULL )
 288                 listener( owner, self, ( mlt_frame )args[ 0 ] );
 289 }
 290
 291 /** The transmitter for the consumer-frame-render event
 292  *
 293  * Invokes the listener.
 294  *
 295  * \private \memberof mlt_consumer_s
 296  * \param listener a function pointer that will be invoked
 297  * \param owner the events object that will be passed to \p listener
 298  * \param self  a service that will be passed to \p listener
 299  * \param args an array of pointers - the first entry is passed as a string to \p listener
 300  */
 301
 302 static void mlt_consumer_frame_render( mlt_listener listener, mlt_properties owner, mlt_service self, void **args )
 303 {
 304         if ( listener != NULL )
 305                 listener( owner, self, ( mlt_frame )args[ 0 ] );
 306 }
 307
 308 /** A listener on the consumer-frame-show event
 309  *
 310  * Saves the position of the frame shown.
 311  *
 312  * \private \memberof mlt_consumer_s
 313  * \param owner the events object
 314  * \param consumer the consumer on which this event occurred
 315  * \param frame the frame that was shown
 316  */
 317
 318 static void on_consumer_frame_show( mlt_properties owner, mlt_consumer consumer, mlt_frame frame )
 319 {
 320         if ( frame )
 321                 consumer->position = mlt_frame_get_position( frame );
 322 }
 323
 324 /** Create a new consumer.
 325  *
 326  * \public \memberof mlt_consumer_s
 327  * \param profile a profile (optional, but recommended)
 328  * \return a new consumer
 329  */
 330
 331 mlt_consumer mlt_consumer_new( mlt_profile profile )
 332 {
 333         // Create the memory for the structure
 334         mlt_consumer self = malloc( sizeof( struct mlt_consumer_s ) );
 335
 336         // Initialise it
 337         if ( self != NULL )
 338                 mlt_consumer_init( self, NULL, profile );
 339
 340         // Return it
 341         return self;
 342 }
 343
 344 /** Get the parent service object.
 345  *
 346  * \public \memberof mlt_consumer_s
 347  * \param self a consumer
 348  * \return the parent service class
 349  * \see MLT_CONSUMER_SERVICE
 350  */
 351
 352 mlt_service mlt_consumer_service( mlt_consumer self )
 353 {
 354         return self != NULL ? &self->parent : NULL;
 355 }
 356
 357 /** Get the consumer properties.
 358  *
 359  * \public \memberof mlt_consumer_s
 360  * \param self a consumer
 361  * \return the consumer's properties list
 362  * \see MLT_CONSUMER_PROPERTIES
 363  */
 364
 365 mlt_properties mlt_consumer_properties( mlt_consumer self )
 366 {
 367         return self != NULL ? MLT_SERVICE_PROPERTIES( &self->parent ) : NULL;
 368 }
 369
 370 /** Connect the consumer to the producer.
 371  *
 372  * \public \memberof mlt_consumer_s
 373  * \param self a consumer
 374  * \param producer a producer
 375  * \return > 0 warning, == 0 success, < 0 serious error,
 376  *         1 = this service does not accept input,
 377  *         2 = the producer is invalid,
 378  *         3 = the producer is already registered with this consumer
 379  */
 380
 381 int mlt_consumer_connect( mlt_consumer self, mlt_service producer )
 382 {
 383         return mlt_service_connect_producer( &self->parent, producer, 0 );
 384 }
 385
 386 /** Start the consumer.
 387  *
 388  * \public \memberof mlt_consumer_s
 389  * \param self a consumer
 390  * \return true if there was an error
 391  */
 392
 393 int mlt_consumer_start( mlt_consumer self )
 394 {
 395         if ( !mlt_consumer_is_stopped( self ) )
 396                 return 0;
 397
 398         // Stop listening to the property-changed event
 399         mlt_event_block( self->event_listener );
 400
 401         // Get the properies
 402         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 403
 404         // Determine if there's a test card producer
 405         char *test_card = mlt_properties_get( properties, "test_card" );
 406
 407         // Just to make sure nothing is hanging around...
 408         self->put = NULL;
 409         self->put_active = 1;
 410
 411         // Deal with it now.
 412         if ( test_card != NULL )
 413         {
 414                 if ( mlt_properties_get_data( properties, "test_card_producer", NULL ) == NULL )
 415                 {
 416                         // Create a test card producer
 417                         mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 418                         mlt_producer producer = mlt_factory_producer( profile, NULL, test_card );
 419
 420                         // Do we have a producer
 421                         if ( producer != NULL )
 422                         {
 423                                 // Test card should loop I guess...
 424                                 mlt_properties_set( MLT_PRODUCER_PROPERTIES( producer ), "eof", "loop" );
 425                                 //mlt_producer_set_speed( producer, 0 );
 426                                 //mlt_producer_set_in_and_out( producer, 0, 0 );
 427
 428                                 // Set the test card on the consumer
 429                                 mlt_properties_set_data( properties, "test_card_producer", producer, 0, ( mlt_destructor )mlt_producer_close, NULL );
 430                         }
 431                 }
 432         }
 433         else
 434         {
 435                 // Allow the hash table to speed things up
 436                 mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
 437         }
 438
 439         // Set the frame duration in microseconds for the frame-dropping heuristic
 440         int frame_duration = 1000000 / mlt_properties_get_int( properties, "frame_rate_num" ) *
 441                         mlt_properties_get_int( properties, "frame_rate_den" );
 442         mlt_properties_set_int( properties, "frame_duration", frame_duration );
 443
 444         // Check and run an ante command
 445         if ( mlt_properties_get( properties, "ante" ) )
 446                 if ( system( mlt_properties_get( properties, "ante" ) ) == -1 )
 447                         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_ERROR, "system(%s) failed!\n", mlt_properties_get( properties, "ante" ) );
 448
 449         // Set the real_time preference
 450         self->real_time = mlt_properties_get_int( properties, "real_time" );
 451
 452         // For worker threads implementation, buffer must be at least # threads
 453         if ( abs( self->real_time ) > 1 && mlt_properties_get_int( properties, "buffer" ) <= abs( self->real_time ) )
 454                 mlt_properties_set_int( properties, "_buffer", abs( self->real_time ) + 1 );
 455
 456         // Start the service
 457         if ( self->start != NULL )
 458                 return self->start( self );
 459
 460         return 0;
 461 }
 462
 463 /** An alternative method to feed frames into the consumer.
 464  *
 465  * Only valid if the consumer itself is not connected.
 466  *
 467  * \public \memberof mlt_consumer_s
 468  * \param self a consumer
 469  * \param frame a frame
 470  * \return true (ignore self for now)
 471  */
 472
 473 int mlt_consumer_put_frame( mlt_consumer self, mlt_frame frame )
 474 {
 475         int error = 1;
 476
 477         // Get the service assoicated to the consumer
 478         mlt_service service = MLT_CONSUMER_SERVICE( self );
 479
 480         if ( mlt_service_producer( service ) == NULL )
 481         {
 482                 struct timeval now;
 483                 struct timespec tm;
 484                 pthread_mutex_lock( &self->put_mutex );
 485                 while ( self->put_active && self->put != NULL )
 486                 {
 487                         gettimeofday( &now, NULL );
 488                         tm.tv_sec = now.tv_sec + 1;
 489                         tm.tv_nsec = now.tv_usec * 1000;
 490                         pthread_cond_timedwait( &self->put_cond, &self->put_mutex, &tm );
 491                 }
 492                 if ( self->put_active && self->put == NULL )
 493                         self->put = frame;
 494                 else
 495                         mlt_frame_close( frame );
 496                 pthread_cond_broadcast( &self->put_cond );
 497                 pthread_mutex_unlock( &self->put_mutex );
 498         }
 499         else
 500         {
 501                 mlt_frame_close( frame );
 502         }
 503
 504         return error;
 505 }
 506
 507 /** Protected method for consumer to get frames from connected service
 508  *
 509  * \public \memberof mlt_consumer_s
 510  * \param self a consumer
 511  * \return a frame
 512  */
 513
 514 mlt_frame mlt_consumer_get_frame( mlt_consumer self )
 515 {
 516         // Frame to return
 517         mlt_frame frame = NULL;
 518
 519         // Get the service assoicated to the consumer
 520         mlt_service service = MLT_CONSUMER_SERVICE( self );
 521
 522         // Get the consumer properties
 523         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 524
 525         // Get the frame
 526         if ( mlt_service_producer( service ) == NULL && mlt_properties_get_int( properties, "put_mode" ) )
 527         {
 528                 struct timeval now;
 529                 struct timespec tm;
 530                 pthread_mutex_lock( &self->put_mutex );
 531                 while ( self->put_active && self->put == NULL )
 532                 {
 533                         gettimeofday( &now, NULL );
 534                         tm.tv_sec = now.tv_sec + 1;
 535                         tm.tv_nsec = now.tv_usec * 1000;
 536                         pthread_cond_timedwait( &self->put_cond, &self->put_mutex, &tm );
 537                 }
 538                 frame = self->put;
 539                 self->put = NULL;
 540                 pthread_cond_broadcast( &self->put_cond );
 541                 pthread_mutex_unlock( &self->put_mutex );
 542                 if ( frame != NULL )
 543                         mlt_service_apply_filters( service, frame, 0 );
 544         }
 545         else if ( mlt_service_producer( service ) != NULL )
 546         {
 547                 mlt_service_get_frame( service, &frame, 0 );
 548         }
 549         else
 550         {
 551                 frame = mlt_frame_init( service );
 552         }
 553
 554         if ( frame != NULL )
 555         {
 556                 // Get the frame properties
 557                 mlt_properties frame_properties = MLT_FRAME_PROPERTIES( frame );
 558
 559                 // Get the test card producer
 560                 mlt_producer test_card = mlt_properties_get_data( properties, "test_card_producer", NULL );
 561
 562                 // Attach the test frame producer to it.
 563                 if ( test_card != NULL )
 564                         mlt_properties_set_data( frame_properties, "test_card_producer", test_card, 0, NULL, NULL );
 565
 566                 // Attach the rescale property
 567                 mlt_properties_set( frame_properties, "rescale.interp", mlt_properties_get( properties, "rescale" ) );
 568
 569                 // Aspect ratio and other jiggery pokery
 570                 mlt_properties_set_double( frame_properties, "consumer_aspect_ratio", mlt_properties_get_double( properties, "aspect_ratio" ) );
 571                 mlt_properties_set_int( frame_properties, "consumer_deinterlace", mlt_properties_get_int( properties, "progressive" ) | mlt_properties_get_int( properties, "deinterlace" ) );
 572                 mlt_properties_set( frame_properties, "deinterlace_method", mlt_properties_get( properties, "deinterlace_method" ) );
 573                 mlt_properties_set_int( frame_properties, "consumer_tff", mlt_properties_get_int( properties, "top_field_first" ) );
 574         }
 575
 576         // Return the frame
 577         return frame;
 578 }
 579
 580 /** Compute the time difference between now and a time value.
 581  *
 582  * \private \memberof mlt_consumer_s
 583  * \param time1 a time value to be compared against now
 584  * \return the difference in microseconds
 585  */
 586
 587 static inline long time_difference( struct timeval *time1 )
 588 {
 589         struct timeval time2;
 590         time2.tv_sec = time1->tv_sec;
 591         time2.tv_usec = time1->tv_usec;
 592         gettimeofday( time1, NULL );
 593         return time1->tv_sec * 1000000 + time1->tv_usec - time2.tv_sec * 1000000 - time2.tv_usec;
 594 }
 595
 596 /** The thread procedure for asynchronously pulling frames through the service
 597  * network connected to a consumer.
 598  *
 599  * \private \memberof mlt_consumer_s
 600  * \param arg a consumer
 601  */
 602
 603 static void *consumer_read_ahead_thread( void *arg )
 604 {
 605         // The argument is the consumer
 606         mlt_consumer self = arg;
 607
 608         // Get the properties of the consumer
 609         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 610
 611         // Get the width and height
 612         int width = mlt_properties_get_int( properties, "width" );
 613         int height = mlt_properties_get_int( properties, "height" );
 614
 615         // See if video is turned off
 616         int video_off = mlt_properties_get_int( properties, "video_off" );
 617         int preview_off = mlt_properties_get_int( properties, "preview_off" );
 618         int preview_format = mlt_properties_get_int( properties, "preview_format" );
 619
 620         // Get the audio settings
 621         mlt_audio_format afmt = mlt_audio_s16;
 622         int counter = 0;
 623         double fps = mlt_properties_get_double( properties, "fps" );
 624         int channels = mlt_properties_get_int( properties, "channels" );
 625         int frequency = mlt_properties_get_int( properties, "frequency" );
 626         int samples = 0;
 627         void *audio = NULL;
 628
 629         // See if audio is turned off
 630         int audio_off = mlt_properties_get_int( properties, "audio_off" );
 631
 632         // Get the maximum size of the buffer
 633         int buffer = mlt_properties_get_int( properties, "buffer" ) + 1;
 634
 635         // General frame variable
 636         mlt_frame frame = NULL;
 637         uint8_t *image = NULL;
 638
 639         // Time structures
 640         struct timeval ante;
 641
 642         // Average time for get_frame and get_image
 643         int count = 0;
 644         int skipped = 0;
 645         int64_t time_process = 0;
 646         int skip_next = 0;
 647         mlt_position pos = 0;
 648         mlt_position start_pos = 0;
 649         mlt_position last_pos = 0;
 650         int frame_duration = mlt_properties_get_int( properties, "frame_duration" );
 651         int drop_max = mlt_properties_get_int( properties, "drop_max" );
 652
 653         if ( preview_off && preview_format != 0 )
 654                 self->format = preview_format;
 655
 656         // Get the first frame
 657         frame = mlt_consumer_get_frame( self );
 658
 659         if ( frame )
 660         {
 661                 // Get the image of the first frame
 662                 if ( !video_off )
 663                 {
 664                         mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 665                         mlt_frame_get_image( frame, &image, &self->format, &width, &height, 0 );
 666                 }
 667
 668                 if ( !audio_off )
 669                 {
 670                         samples = mlt_sample_calculator( fps, frequency, counter++ );
 671                         mlt_frame_get_audio( frame, &audio, &afmt, &frequency, &channels, &samples );
 672                 }
 673
 674                 // Mark as rendered
 675                 mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 676                 last_pos = start_pos = pos = mlt_frame_get_position( frame );
 677         }
 678
 679         // Get the starting time (can ignore the times above)
 680         gettimeofday( &ante, NULL );
 681
 682         // Continue to read ahead
 683         while ( self->ahead )
 684         {
 685                 // Put the current frame into the queue
 686                 pthread_mutex_lock( &self->queue_mutex );
 687                 while( self->ahead && mlt_deque_count( self->queue ) >= buffer )
 688                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
 689                 mlt_deque_push_back( self->queue, frame );
 690                 pthread_cond_broadcast( &self->queue_cond );
 691                 pthread_mutex_unlock( &self->queue_mutex );
 692
 693                 // Get the next frame
 694                 frame = mlt_consumer_get_frame( self );
 695
 696                 // If there's no frame, we're probably stopped...
 697                 if ( frame == NULL )
 698                         continue;
 699                 pos = mlt_frame_get_position( frame );
 700
 701                 // Increment the counter used for averaging processing cost
 702                 count ++;
 703
 704                 // All non-normal playback frames should be shown
 705                 if ( mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "_speed" ) != 1 )
 706                 {
 707 #ifdef DEINTERLACE_ON_NOT_NORMAL_SPEED
 708                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "consumer_deinterlace", 1 );
 709 #endif
 710                         // Indicate seeking or trick-play
 711                         start_pos = pos;
 712                 }
 713
 714                 // If skip flag not set or frame-dropping disabled
 715                 if ( !skip_next || self->real_time == -1 )
 716                 {
 717                         if ( !video_off )
 718                         {
 719                                 // Reset width/height - could have been changed by previous mlt_frame_get_image
 720                                 width = mlt_properties_get_int( properties, "width" );
 721                                 height = mlt_properties_get_int( properties, "height" );
 722
 723                                 // Get the image
 724                                 mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 725                                 mlt_frame_get_image( frame, &image, &self->format, &width, &height, 0 );
 726                         }
 727
 728                         // Indicate the rendered image is available.
 729                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 730
 731                         // Reset consecutively-skipped counter
 732                         skipped = 0;
 733                 }
 734                 else // Skip image processing
 735                 {
 736                         // Increment the number of consecutively-skipped frames
 737                         skipped++;
 738
 739                         // If too many (1 sec) consecutively-skipped frames
 740                         if ( skipped > drop_max )
 741                         {
 742                                 // Reset cost tracker
 743                                 time_process = 0;
 744                                 count = 1;
 745                                 mlt_log_verbose( self, "too many frames dropped - forcing next frame\n" );
 746                         }
 747                 }
 748
 749                 // Always process audio
 750                 if ( !audio_off )
 751                 {
 752                         samples = mlt_sample_calculator( fps, frequency, counter++ );
 753                         mlt_frame_get_audio( frame, &audio, &afmt, &frequency, &channels, &samples );
 754                 }
 755
 756                 // Get the time to process this frame
 757                 int64_t time_current = time_difference( &ante );
 758
 759                 // If the current time is not suddenly some large amount
 760                 if ( time_current < time_process / count * 20 || !time_process || count < 5 )
 761                 {
 762                         // Accumulate the cost for processing this frame
 763                         time_process += time_current;
 764                 }
 765                 else
 766                 {
 767                         mlt_log_debug( self, "current %"PRId64" threshold %"PRId64" count %d\n",
 768                                 time_current, (int64_t) (time_process / count * 20), count );
 769                         // Ignore the cost of this frame's time
 770                         count--;
 771                 }
 772
 773                 // Determine if we started, resumed, or seeked
 774                 if ( pos != last_pos + 1 )
 775                         start_pos = pos;
 776                 last_pos = pos;
 777
 778                 // Do not skip the first 20% of buffer at start, resume, or seek
 779                 if ( pos - start_pos <= buffer / 5 + 1 )
 780                 {
 781                         // Reset cost tracker
 782                         time_process = 0;
 783                         count = 1;
 784                 }
 785
 786                 // Reset skip flag
 787                 skip_next = 0;
 788
 789                 // Only consider skipping if the buffer level is low (or really small)
 790                 if ( mlt_deque_count( self->queue ) <= buffer / 5 + 1 )
 791                 {
 792                         // Skip next frame if average cost exceeds frame duration.
 793                         if ( time_process / count > frame_duration )
 794                                 skip_next = 1;
 795                         if ( skip_next )
 796                                 mlt_log_debug( self, "avg usec %"PRId64" (%"PRId64"/%d) duration %d\n",
 797                                         time_process/count, time_process, count, frame_duration);
 798                 }
 799         }
 800
 801         // Remove the last frame
 802         mlt_frame_close( frame );
 803
 804         return NULL;
 805 }
 806
 807 /** Locate the first unprocessed frame in the queue.
 808  *
 809  * When playing with realtime behavior, we do not use the true head, but
 810  * rather an adjusted process_head. The process_head is adjusted based on
 811  * the rate of frame-dropping or recovery from frame-dropping. The idea is
 812  * that as the level of frame-dropping increases to move the process_head
 813  * closer to the tail because the frames are not completing processing prior
 814  * to their playout! Then, as frames are not dropped the process_head moves
 815  * back closer to the head of the queue so that worker threads can work
 816  * ahead of the playout point (queue head).
 817  *
 818  * \private \memberof mlt_consumer_s
 819  * \param self a consumer
 820  * \return an index into the queue
 821  */
 822
 823 static inline int first_unprocessed_frame( mlt_consumer self )
 824 {
 825         int index = self->real_time <= 0 ? 0 : self->process_head;
 826         while ( index < mlt_deque_count( self->queue ) && MLT_FRAME( mlt_deque_peek( self->queue, index ) )->is_processing )
 827                 index++;
 828         return index;
 829 }
 830
 831 /** The worker thread procedure for parallel processing frames.
 832  *
 833  * \private \memberof mlt_consumer_s
 834  * \param arg a consumer
 835  */
 836
 837 static void *consumer_worker_thread( void *arg )
 838 {
 839         // The argument is the consumer
 840         mlt_consumer self = arg;
 841
 842         // Get the properties of the consumer
 843         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 844
 845         // Get the width and height
 846         int width = mlt_properties_get_int( properties, "width" );
 847         int height = mlt_properties_get_int( properties, "height" );
 848         mlt_image_format format = self->format;
 849
 850         // See if video is turned off
 851         int video_off = mlt_properties_get_int( properties, "video_off" );
 852         int preview_off = mlt_properties_get_int( properties, "preview_off" );
 853         int preview_format = mlt_properties_get_int( properties, "preview_format" );
 854
 855         // General frame variable
 856         mlt_frame frame = NULL;
 857         uint8_t *image = NULL;
 858
 859         if ( preview_off && preview_format != 0 )
 860                 format = preview_format;
 861
 862         // Continue to read ahead
 863         while ( self->ahead )
 864         {
 865                 // Get the next unprocessed frame from the work queue
 866                 pthread_mutex_lock( &self->queue_mutex );
 867                 int index = first_unprocessed_frame( self );
 868                 while ( self->ahead && index >= mlt_deque_count( self->queue ) )
 869                 {
 870                         mlt_log_debug( MLT_CONSUMER_SERVICE(self), "waiting in worker index = %d queue count = %d\n",
 871                                 index, mlt_deque_count( self->queue ) );
 872                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
 873                         index = first_unprocessed_frame( self );
 874                 }
 875
 876                 // Mark the frame for processing
 877                 frame = mlt_deque_peek( self->queue, index );
 878                 if ( frame )
 879                 {
 880                         mlt_log_debug( MLT_CONSUMER_SERVICE(self), "worker processing index = %d frame %d queue count = %d\n",
 881                                 index, mlt_frame_get_position(frame), mlt_deque_count( self->queue ) );
 882                         frame->is_processing = 1;
 883                         mlt_properties_inc_ref( MLT_FRAME_PROPERTIES( frame ) );
 884                 }
 885                 pthread_mutex_unlock( &self->queue_mutex );
 886
 887                 // If there's no frame, we're probably stopped...
 888                 if ( frame == NULL )
 889                         continue;
 890
 891 #ifdef DEINTERLACE_ON_NOT_NORMAL_SPEED
 892                 // All non normal playback frames should be shown
 893                 if ( mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "_speed" ) != 1 )
 894                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "consumer_deinterlace", 1 );
 895 #endif
 896
 897                 // Get the image
 898                 if ( !video_off )
 899                 {
 900                         // Fetch width/height again
 901                         width = mlt_properties_get_int( properties, "width" );
 902                         height = mlt_properties_get_int( properties, "height" );
 903                         mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 904                         mlt_frame_get_image( frame, &image, &format, &width, &height, 0 );
 905                 }
 906                 mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 907                 mlt_frame_close( frame );
 908
 909                 // Tell a waiting thread (non-realtime main consumer thread) that we are done.
 910                 pthread_mutex_lock( &self->done_mutex );
 911                 pthread_cond_broadcast( &self->done_cond );
 912                 pthread_mutex_unlock( &self->done_mutex );
 913         }
 914
 915         return NULL;
 916 }
 917
 918 /** Start the read/render thread.
 919  *
 920  * \private \memberof mlt_consumer_s
 921  * \param self a consumer
 922  */
 923
 924 static void consumer_read_ahead_start( mlt_consumer self )
 925 {
 926         // We're running now
 927         self->ahead = 1;
 928
 929         // Create the frame queue
 930         self->queue = mlt_deque_init( );
 931
 932         // Create the queue mutex
 933         pthread_mutex_init( &self->queue_mutex, NULL );
 934
 935         // Create the condition
 936         pthread_cond_init( &self->queue_cond, NULL );
 937
 938         // Create the read ahead
 939         if ( mlt_properties_get( MLT_CONSUMER_PROPERTIES( self ), "priority" ) )
 940         {
 941                 struct sched_param priority;
 942                 priority.sched_priority = mlt_properties_get_int( MLT_CONSUMER_PROPERTIES( self ), "priority" );
 943                 pthread_attr_t thread_attributes;
 944                 pthread_attr_init( &thread_attributes );
 945                 pthread_attr_setschedpolicy( &thread_attributes, SCHED_OTHER );
 946                 pthread_attr_setschedparam( &thread_attributes, &priority );
 947                 pthread_attr_setinheritsched( &thread_attributes, PTHREAD_EXPLICIT_SCHED );
 948                 pthread_attr_setscope( &thread_attributes, PTHREAD_SCOPE_SYSTEM );
 949                 if ( pthread_create( &self->ahead_thread, &thread_attributes, consumer_read_ahead_thread, self ) < 0 )
 950                         pthread_create( &self->ahead_thread, NULL, consumer_read_ahead_thread, self );
 951                 pthread_attr_destroy( &thread_attributes );
 952         }
 953         else
 954         {
 955                 pthread_create( &self->ahead_thread, NULL, consumer_read_ahead_thread, self );
 956         }
 957         self->started = 1;
 958 }
 959
 960 /** Start the worker threads.
 961  *
 962  * \private \memberof mlt_consumer_s
 963  * \param self a consumer
 964  */
 965
 966 static void consumer_work_start( mlt_consumer self )
 967 {
 968         int n = abs( self->real_time );
 969         pthread_t *thread = calloc( 1, sizeof( pthread_t ) * n );
 970
 971         // We're running now
 972         self->ahead = 1;
 973
 974         // These keep track of the accelleration of frame dropping or recovery.
 975         self->consecutive_dropped = 0;
 976         self->consecutive_rendered = 0;
 977
 978         // This is the position in the queue from which to look for a frame to process.
 979         // If we always start from the head, then we may likely not complete processing
 980         // before the frame is played out.
 981         self->process_head = 0;
 982
 983         // Create the queues
 984         self->queue = mlt_deque_init();
 985         self->worker_threads = mlt_deque_init();
 986
 987         // Create the mutexes
 988         pthread_mutex_init( &self->queue_mutex, NULL );
 989         pthread_mutex_init( &self->done_mutex, NULL );
 990
 991         // Create the conditions
 992         pthread_cond_init( &self->queue_cond, NULL );
 993         pthread_cond_init( &self->done_cond, NULL );
 994
 995         // Create the read ahead
 996         if ( mlt_properties_get( MLT_CONSUMER_PROPERTIES( self ), "priority" ) )
 997         {
 998
 999                 struct sched_param priority;
1000                 pthread_attr_t thread_attributes;
1001
1002                 priority.sched_priority = mlt_properties_get_int( MLT_CONSUMER_PROPERTIES( self ), "priority" );
1003                 pthread_attr_init( &thread_attributes );
1004                 pthread_attr_setschedpolicy( &thread_attributes, SCHED_OTHER );
1005                 pthread_attr_setschedparam( &thread_attributes, &priority );
1006                 pthread_attr_setinheritsched( &thread_attributes, PTHREAD_EXPLICIT_SCHED );
1007                 pthread_attr_setscope( &thread_attributes, PTHREAD_SCOPE_SYSTEM );
1008
1009                 while ( n-- )
1010                 {
1011                         if ( pthread_create( thread, &thread_attributes, consumer_worker_thread, self ) < 0 )
1012                                 if ( pthread_create( thread, NULL, consumer_worker_thread, self ) == 0 )
1013                                         mlt_deque_push_back( self->worker_threads, thread );
1014                         thread++;
1015                 }
1016                 pthread_attr_destroy( &thread_attributes );
1017         }
1018
1019         else
1020         {
1021                 while ( n-- )
1022                 {
1023                         if ( pthread_create( thread, NULL, consumer_worker_thread, self ) == 0 )
1024                                 mlt_deque_push_back( self->worker_threads, thread );
1025                         thread++;
1026                 }
1027         }
1028         self->started = 1;
1029 }
1030
1031 /** Stop the read/render thread.
1032  *
1033  * \private \memberof mlt_consumer_s
1034  * \param self a consumer
1035  */
1036
1037 static void consumer_read_ahead_stop( mlt_consumer self )
1038 {
1039         // Make sure we're running
1040         if ( self->started )
1041         {
1042                 // Inform thread to stop
1043                 self->ahead = 0;
1044
1045                 // Broadcast to the condition in case it's waiting
1046                 pthread_mutex_lock( &self->queue_mutex );
1047                 pthread_cond_broadcast( &self->queue_cond );
1048                 pthread_mutex_unlock( &self->queue_mutex );
1049
1050                 // Broadcast to the put condition in case it's waiting
1051                 pthread_mutex_lock( &self->put_mutex );
1052                 pthread_cond_broadcast( &self->put_cond );
1053                 pthread_mutex_unlock( &self->put_mutex );
1054
1055                 // Join the thread
1056                 pthread_join( self->ahead_thread, NULL );
1057                 self->started = 0;
1058
1059                 // Destroy the frame queue mutex
1060                 pthread_mutex_destroy( &self->queue_mutex );
1061
1062                 // Destroy the condition
1063                 pthread_cond_destroy( &self->queue_cond );
1064
1065                 // Wipe the queue
1066                 while ( mlt_deque_count( self->queue ) )
1067                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1068
1069                 // Close the queue
1070                 mlt_deque_close( self->queue );
1071         }
1072 }
1073
1074 /** Stop the worker threads.
1075  *
1076  * \private \memberof mlt_consumer_s
1077  * \param self a consumer
1078  */
1079
1080 static void consumer_work_stop( mlt_consumer self )
1081 {
1082         // Make sure we're running
1083         if ( self->started )
1084         {
1085                 // Inform thread to stop
1086                 self->ahead = 0;
1087
1088                 // Broadcast to the queue condition in case it's waiting
1089                 pthread_mutex_lock( &self->queue_mutex );
1090                 pthread_cond_broadcast( &self->queue_cond );
1091                 pthread_mutex_unlock( &self->queue_mutex );
1092
1093                 // Broadcast to the put condition in case it's waiting
1094                 pthread_mutex_lock( &self->put_mutex );
1095                 pthread_cond_broadcast( &self->put_cond );
1096                 pthread_mutex_unlock( &self->put_mutex );
1097
1098                 // Broadcast to the done condition in case it's waiting
1099                 pthread_mutex_lock( &self->done_mutex );
1100                 pthread_cond_broadcast( &self->done_cond );
1101                 pthread_mutex_unlock( &self->done_mutex );
1102
1103                 // Join the threads
1104                 pthread_t *thread;
1105                 while ( ( thread = mlt_deque_pop_back( self->worker_threads ) ) )
1106                         pthread_join( *thread, NULL );
1107
1108                 // Deallocate the array of threads
1109                 if ( thread )
1110                         free( thread );
1111
1112                 // Indicate that worker threads no longer running
1113                 self->started = 0;
1114
1115                 // Destroy the mutexes
1116                 pthread_mutex_destroy( &self->queue_mutex );
1117                 pthread_mutex_destroy( &self->done_mutex );
1118
1119                 // Destroy the conditions
1120                 pthread_cond_destroy( &self->queue_cond );
1121                 pthread_cond_destroy( &self->done_cond );
1122
1123                 // Wipe the queues
1124                 while ( mlt_deque_count( self->queue ) )
1125                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1126
1127                 // Close the queues
1128                 mlt_deque_close( self->queue );
1129                 mlt_deque_close( self->worker_threads );
1130         }
1131 }
1132
1133 /** Flush the read/render thread's buffer.
1134  *
1135  * \public \memberof mlt_consumer_s
1136  * \param self a consumer
1137  */
1138
1139 void mlt_consumer_purge( mlt_consumer self )
1140 {
1141         if ( self->ahead )
1142         {
1143                 pthread_mutex_lock( &self->queue_mutex );
1144                 while ( mlt_deque_count( self->queue ) )
1145                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1146                 pthread_cond_broadcast( &self->queue_cond );
1147                 pthread_mutex_unlock( &self->queue_mutex );
1148         }
1149 }
1150
1151 /** Use multiple worker threads and a work queue.
1152  */
1153
1154 static mlt_frame worker_get_frame( mlt_consumer self, mlt_properties properties )
1155 {
1156         // Frame to return
1157         mlt_frame frame = NULL;
1158
1159         double fps = mlt_properties_get_double( properties, "fps" );
1160         int threads = abs( self->real_time );
1161         int buffer = mlt_properties_get_int( properties, "_buffer" );
1162         buffer = buffer > 0 ? buffer : mlt_properties_get_int( properties, "buffer" );
1163         // This is a heuristic to determine a suitable minimum buffer size for the number of threads.
1164         int headroom = 2 + threads * threads;
1165         buffer = buffer < headroom ? headroom : buffer;
1166
1167         // Start worker threads if not already started.
1168         if ( ! self->ahead )
1169         {
1170                 int prefill = mlt_properties_get_int( properties, "prefill" );
1171                 prefill = prefill > 0 && prefill < buffer ? prefill : buffer;
1172
1173                 consumer_work_start( self );
1174
1175                 // Fill the work queue.
1176                 int i = buffer;
1177                 while ( self->ahead && i-- )
1178                 {
1179                         frame = mlt_consumer_get_frame( self );
1180                         if ( frame )
1181                         {
1182                                 pthread_mutex_lock( &self->queue_mutex );
1183                                 mlt_deque_push_back( self->queue, frame );
1184                                 pthread_cond_signal( &self->queue_cond );
1185                                 pthread_mutex_unlock( &self->queue_mutex );
1186                         }
1187                 }
1188
1189                 // Wait for prefill
1190                 while ( self->ahead && first_unprocessed_frame( self ) < prefill )
1191                 {
1192                         pthread_mutex_lock( &self->done_mutex );
1193                         pthread_cond_wait( &self->done_cond, &self->done_mutex );
1194                         pthread_mutex_unlock( &self->done_mutex );
1195                 }
1196                 self->process_head = threads;
1197         }
1198
1199 //      mlt_log_verbose( MLT_CONSUMER_SERVICE(self), "size %d done count %d work count %d process_head %d\n",
1200 //              threads, first_unprocessed_frame( self ), mlt_deque_count( self->queue ), self->process_head );
1201
1202         // Feed the work queue
1203         while ( self->ahead && mlt_deque_count( self->queue ) < buffer )
1204         {
1205                 frame = mlt_consumer_get_frame( self );
1206                 if ( ! frame )
1207                         return frame;
1208                 pthread_mutex_lock( &self->queue_mutex );
1209                 mlt_deque_push_back( self->queue, frame );
1210                 pthread_cond_signal( &self->queue_cond );
1211                 pthread_mutex_unlock( &self->queue_mutex );
1212         }
1213
1214         // Wait if not realtime.
1215         mlt_frame head_frame = MLT_FRAME( mlt_deque_peek_front( self->queue ) );
1216         while ( self->ahead && self->real_time < 0 &&
1217                 !( head_frame && mlt_properties_get_int( MLT_FRAME_PROPERTIES( head_frame ), "rendered" ) ) )
1218         {
1219                 pthread_mutex_lock( &self->done_mutex );
1220                 pthread_cond_wait( &self->done_cond, &self->done_mutex );
1221                 pthread_mutex_unlock( &self->done_mutex );
1222         }
1223
1224         // Get the frame from the queue.
1225         pthread_mutex_lock( &self->queue_mutex );
1226         frame = mlt_deque_pop_front( self->queue );
1227         pthread_mutex_unlock( &self->queue_mutex );
1228
1229         // Adapt the worker process head to the runtime conditions.
1230         if ( self->real_time > 0 )
1231         {
1232                 if ( frame && mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "rendered" ) )
1233                 {
1234                         self->consecutive_dropped = 0;
1235                         if ( self->process_head > threads && self->consecutive_rendered >= self->process_head )
1236                                 self->process_head--;
1237                         else
1238                                 self->consecutive_rendered++;
1239                 }
1240                 else
1241                 {
1242                         self->consecutive_rendered = 0;
1243                         if ( self->process_head < buffer - threads && self->consecutive_dropped > threads )
1244                                 self->process_head++;
1245                         else
1246                                 self->consecutive_dropped++;
1247                 }
1248 //              mlt_log_verbose( MLT_CONSUMER_SERVICE(self), "dropped %d rendered %d process_head %d\n",
1249 //                      self->consecutive_dropped, self->consecutive_rendered, self->process_head );
1250
1251                 // Check for too many consecutively dropped frames
1252                 if ( self->consecutive_dropped > mlt_properties_get_int( properties, "drop_max" ) )
1253                 {
1254                         int orig_buffer = mlt_properties_get_int( properties, "buffer" );
1255                         int prefill = mlt_properties_get_int( properties, "prefill" );
1256                         mlt_log_verbose( self, "too many frames dropped - " );
1257
1258                         // If using a default low-latency buffer level (SDL) and below the limit
1259                         if ( ( orig_buffer == 1 || prefill == 1 ) && buffer < (threads + 1) * 10 )
1260                         {
1261                                 // Auto-scale the buffer to compensate
1262                                 mlt_log_verbose( self, "increasing buffer to %d\n", buffer + threads );
1263                                 mlt_properties_set_int( properties, "_buffer", buffer + threads );
1264                                 self->consecutive_dropped = fps / 2;
1265                         }
1266                         else
1267                         {
1268                                 // Tell the consumer to render it
1269                                 mlt_log_verbose( self, "forcing next frame\n" );
1270                                 mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
1271                                 self->consecutive_dropped = 0;
1272                         }
1273                 }
1274         }
1275
1276         return frame;
1277 }
1278
1279 /** Get the next frame from the producer connected to a consumer.
1280  *
1281  * Typically, one uses this instead of \p mlt_consumer_get_frame to make
1282  * the asynchronous/real-time behavior configurable at runtime.
1283  * You should close the frame returned from this when you are done with it.
1284  *
1285  * \public \memberof mlt_consumer_s
1286  * \param self a consumer
1287  * \return a frame
1288  */
1289
1290 mlt_frame mlt_consumer_rt_frame( mlt_consumer self )
1291 {
1292         // Frame to return
1293         mlt_frame frame = NULL;
1294
1295         // Get the properties
1296         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
1297
1298         // Check if the user has requested real time or not
1299         if ( self->real_time > 1 || self->real_time < -1 )
1300         {
1301                 // see above
1302                 return worker_get_frame( self, properties );
1303         }
1304         else if ( self->real_time == 1 || self->real_time == -1 )
1305         {
1306                 int size = 1;
1307
1308                 // Is the read ahead running?
1309                 if ( self->ahead == 0 )
1310                 {
1311                         int buffer = mlt_properties_get_int( properties, "buffer" );
1312                         int prefill = mlt_properties_get_int( properties, "prefill" );
1313                         consumer_read_ahead_start( self );
1314                         if ( buffer > 1 )
1315                                 size = prefill > 0 && prefill < buffer ? prefill : buffer;
1316                 }
1317
1318                 // Get frame from queue
1319                 pthread_mutex_lock( &self->queue_mutex );
1320                 while( self->ahead && mlt_deque_count( self->queue ) < size )
1321                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
1322                 frame = mlt_deque_pop_front( self->queue );
1323                 pthread_cond_broadcast( &self->queue_cond );
1324                 pthread_mutex_unlock( &self->queue_mutex );
1325         }
1326         else // real_time == 0
1327         {
1328                 // Get the frame in non real time
1329                 frame = mlt_consumer_get_frame( self );
1330
1331                 // This isn't true, but from the consumers perspective it is
1332                 if ( frame != NULL )
1333                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
1334         }
1335
1336         return frame;
1337 }
1338
1339 /** Callback for the implementation to indicate a stopped condition.
1340  *
1341  * \public \memberof mlt_consumer_s
1342  * \param self a consumer
1343  */
1344
1345 void mlt_consumer_stopped( mlt_consumer self )
1346 {
1347         mlt_properties_set_int( MLT_CONSUMER_PROPERTIES( self ), "running", 0 );
1348         mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-stopped", NULL );
1349         mlt_event_unblock( self->event_listener );
1350 }
1351
1352 /** Stop the consumer.
1353  *
1354  * \public \memberof mlt_consumer_s
1355  * \param self a consumer
1356  * \return true if there was an error
1357  */
1358
1359 int mlt_consumer_stop( mlt_consumer self )
1360 {
1361         // Get the properies
1362         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
1363
1364         // Just in case...
1365         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping put waiting\n" );
1366         pthread_mutex_lock( &self->put_mutex );
1367         self->put_active = 0;
1368         pthread_cond_broadcast( &self->put_cond );
1369         pthread_mutex_unlock( &self->put_mutex );
1370
1371         // Stop the consumer
1372         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping consumer\n" );
1373
1374         // Cancel the read ahead threads
1375         self->ahead = 0;
1376         if ( self->started )
1377         {
1378                 // Unblock the consumer calling mlt_consumer_rt_frame
1379                 pthread_mutex_lock( &self->queue_mutex );
1380                 pthread_cond_broadcast( &self->queue_cond );
1381                 pthread_mutex_unlock( &self->queue_mutex );
1382         }
1383
1384         // Invoke the child callback
1385         if ( self->stop != NULL )
1386                 self->stop( self );
1387
1388         // Check if the user has requested real time or not and stop if necessary
1389         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping read_ahead\n" );
1390         if ( abs( self->real_time ) == 1 )
1391                 consumer_read_ahead_stop( self );
1392         else if ( abs( self->real_time ) > 1 )
1393                 consumer_work_stop( self );
1394
1395         // Kill the test card
1396         mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
1397
1398         // Check and run a post command
1399         if ( mlt_properties_get( properties, "post" ) )
1400                 if (system( mlt_properties_get( properties, "post" ) ) == -1 )
1401                         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_ERROR, "system(%s) failed!\n", mlt_properties_get( properties, "post" ) );
1402
1403         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopped\n" );
1404
1405         return 0;
1406 }
1407
1408 /** Determine if the consumer is stopped.
1409  *
1410  * \public \memberof mlt_consumer_s
1411  * \param self a consumer
1412  * \return true if the consumer is stopped
1413  */
1414
1415 int mlt_consumer_is_stopped( mlt_consumer self )
1416 {
1417         // Check if the consumer is stopped
1418         if ( self->is_stopped != NULL )
1419                 return self->is_stopped( self );
1420
1421         return 0;
1422 }
1423
1424 /** Close and destroy the consumer.
1425  *
1426  * \public \memberof mlt_consumer_s
1427  * \param self a consumer
1428  */
1429
1430 void mlt_consumer_close( mlt_consumer self )
1431 {
1432         if ( self != NULL && mlt_properties_dec_ref( MLT_CONSUMER_PROPERTIES( self ) ) <= 0 )
1433         {
1434                 // Get the childs close function
1435                 void ( *consumer_close )( ) = self->close;
1436
1437                 if ( consumer_close )
1438                 {
1439                         // Just in case...
1440                         //mlt_consumer_stop( self );
1441
1442                         self->close = NULL;
1443                         consumer_close( self );
1444                 }
1445                 else
1446                 {
1447                         // Make sure it only gets called once
1448                         self->parent.close = NULL;
1449
1450                         // Destroy the push mutex and condition
1451                         pthread_mutex_destroy( &self->put_mutex );
1452                         pthread_cond_destroy( &self->put_cond );
1453
1454                         mlt_service_close( &self->parent );
1455                 }
1456         }
1457 }
1458
1459 /** Get the position of the last frame shown.
1460  *
1461  * \public \memberof mlt_consumer_s
1462  * \param consumer a consumer
1463  * \return the position
1464  */
1465
1466 mlt_position mlt_consumer_position( mlt_consumer consumer )
1467 {
1468         return consumer->position;
1469 }
1470