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                 mlt_properties_set( properties, "mlt_image_format", mlt_image_format_name( self->format ) );
 104                 mlt_properties_set( properties, "mlt_audio_format", mlt_audio_format_name( mlt_audio_s16 ) );
 105
 106                 mlt_events_register( properties, "consumer-frame-show", ( mlt_transmitter )mlt_consumer_frame_show );
 107                 mlt_events_register( properties, "consumer-frame-render", ( mlt_transmitter )mlt_consumer_frame_render );
 108                 mlt_events_register( properties, "consumer-stopped", NULL );
 109                 mlt_events_listen( properties, self, "consumer-frame-show", ( mlt_listener )on_consumer_frame_show );
 110
 111                 // Register a property-changed listener to handle the profile property -
 112                 // subsequent properties can override the profile
 113                 self->event_listener = mlt_events_listen( properties, self, "property-changed", ( mlt_listener )mlt_consumer_property_changed );
 114
 115                 // Create the push mutex and condition
 116                 pthread_mutex_init( &self->put_mutex, NULL );
 117                 pthread_cond_init( &self->put_cond, NULL );
 118
 119         }
 120         return error;
 121 }
 122
 123 /** Convert the profile into properties on the consumer.
 124  *
 125  * \private \memberof mlt_consumer_s
 126  * \param self a consumer
 127  * \param profile a profile
 128  * \param properties a properties list (typically, the consumer's)
 129  */
 130
 131 static void apply_profile_properties( mlt_consumer self, mlt_profile profile, mlt_properties properties )
 132 {
 133         mlt_event_block( self->event_listener );
 134         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 135         mlt_properties_set_int( properties, "frame_rate_num", profile->frame_rate_num );
 136         mlt_properties_set_int( properties, "frame_rate_den", profile->frame_rate_den );
 137         mlt_properties_set_int( properties, "width", profile->width );
 138         mlt_properties_set_int( properties, "height", profile->height );
 139         mlt_properties_set_int( properties, "progressive", profile->progressive );
 140         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 141         mlt_properties_set_int( properties, "sample_aspect_num", profile->sample_aspect_num );
 142         mlt_properties_set_int( properties, "sample_aspect_den", profile->sample_aspect_den );
 143         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 144         mlt_properties_set_int( properties, "display_aspect_num", profile->display_aspect_num );
 145         mlt_properties_set_int( properties, "display_aspect_num", profile->display_aspect_num );
 146         mlt_properties_set_int( properties, "colorspace", profile->colorspace );
 147         mlt_event_unblock( self->event_listener );
 148 }
 149
 150 /** The property-changed event listener
 151  *
 152  * \private \memberof mlt_consumer_s
 153  * \param owner the events object
 154  * \param self the consumer
 155  * \param name the name of the property that changed
 156  */
 157
 158 static void mlt_consumer_property_changed( mlt_properties owner, mlt_consumer self, char *name )
 159 {
 160         if ( !strcmp( name, "mlt_profile" ) )
 161         {
 162                 // Get the properies
 163                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 164
 165                 // Get the current profile
 166                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 167
 168                 // Load the new profile
 169                 mlt_profile new_profile = mlt_profile_init( mlt_properties_get( properties, name ) );
 170
 171                 if ( new_profile )
 172                 {
 173                         // Copy the profile
 174                         if ( profile != NULL )
 175                         {
 176                                 free( profile->description );
 177                                 memcpy( profile, new_profile, sizeof( struct mlt_profile_s ) );
 178                                 profile->description = strdup( new_profile->description );
 179                         }
 180                         else
 181                         {
 182                                 profile = new_profile;
 183                         }
 184
 185                         // Apply to properties
 186                         apply_profile_properties( self, profile, properties );
 187                         mlt_profile_close( new_profile );
 188                 }
 189         }
 190         else if ( !strcmp( name, "frame_rate_num" ) )
 191         {
 192                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 193                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 194                 if ( profile )
 195                 {
 196                         profile->frame_rate_num = mlt_properties_get_int( properties, "frame_rate_num" );
 197                         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 198                 }
 199         }
 200         else if ( !strcmp( name, "frame_rate_den" ) )
 201         {
 202                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 203                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 204                 if ( profile )
 205                 {
 206                         profile->frame_rate_den = mlt_properties_get_int( properties, "frame_rate_den" );
 207                         mlt_properties_set_double( properties, "fps", mlt_profile_fps( profile ) );
 208                 }
 209         }
 210         else if ( !strcmp( name, "width" ) )
 211         {
 212                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 213                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 214                 if ( profile )
 215                         profile->width = mlt_properties_get_int( properties, "width" );
 216         }
 217         else if ( !strcmp( name, "height" ) )
 218         {
 219                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 220                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 221                 if ( profile )
 222                         profile->height = mlt_properties_get_int( properties, "height" );
 223         }
 224         else if ( !strcmp( name, "progressive" ) )
 225         {
 226                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 227                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 228                 if ( profile )
 229                         profile->progressive = mlt_properties_get_int( properties, "progressive" );
 230         }
 231         else if ( !strcmp( name, "sample_aspect_num" ) )
 232         {
 233                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 234                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 235                 if ( profile )
 236                 {
 237                         profile->sample_aspect_num = mlt_properties_get_int( properties, "sample_aspect_num" );
 238                         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 239                 }
 240         }
 241         else if ( !strcmp( name, "sample_aspect_den" ) )
 242         {
 243                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 244                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 245                 profile->sample_aspect_den = mlt_properties_get_int( properties, "sample_aspect_den" );
 246                 if ( profile )
 247                         mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( profile )  );
 248         }
 249         else if ( !strcmp( name, "display_aspect_num" ) )
 250         {
 251                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 252                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 253                 if ( profile )
 254                 {
 255                         profile->display_aspect_num = mlt_properties_get_int( properties, "display_aspect_num" );
 256                         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 257                 }
 258         }
 259         else if ( !strcmp( name, "display_aspect_den" ) )
 260         {
 261                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 262                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 263                 if ( profile )
 264                 {
 265                         profile->display_aspect_den = mlt_properties_get_int( properties, "display_aspect_den" );
 266                         mlt_properties_set_double( properties, "display_ratio", mlt_profile_dar( profile )  );
 267                 }
 268         }
 269         else if ( !strcmp( name, "colorspace" ) )
 270         {
 271                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 272                 mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 273                 if ( profile )
 274                         profile->colorspace = mlt_properties_get_int( properties, "colorspace" );
 275         }
 276 }
 277
 278 /** The transmitter for the consumer-frame-show event
 279  *
 280  * Invokes the listener.
 281  *
 282  * \private \memberof mlt_consumer_s
 283  * \param listener a function pointer that will be invoked
 284  * \param owner the events object that will be passed to \p listener
 285  * \param self  a service that will be passed to \p listener
 286  * \param args an array of pointers - the first entry is passed as a string to \p listener
 287  */
 288
 289 static void mlt_consumer_frame_show( mlt_listener listener, mlt_properties owner, mlt_service self, void **args )
 290 {
 291         if ( listener != NULL )
 292                 listener( owner, self, ( mlt_frame )args[ 0 ] );
 293 }
 294
 295 /** The transmitter for the consumer-frame-render event
 296  *
 297  * Invokes the listener.
 298  *
 299  * \private \memberof mlt_consumer_s
 300  * \param listener a function pointer that will be invoked
 301  * \param owner the events object that will be passed to \p listener
 302  * \param self  a service that will be passed to \p listener
 303  * \param args an array of pointers - the first entry is passed as a string to \p listener
 304  */
 305
 306 static void mlt_consumer_frame_render( mlt_listener listener, mlt_properties owner, mlt_service self, void **args )
 307 {
 308         if ( listener != NULL )
 309                 listener( owner, self, ( mlt_frame )args[ 0 ] );
 310 }
 311
 312 /** A listener on the consumer-frame-show event
 313  *
 314  * Saves the position of the frame shown.
 315  *
 316  * \private \memberof mlt_consumer_s
 317  * \param owner the events object
 318  * \param consumer the consumer on which this event occurred
 319  * \param frame the frame that was shown
 320  */
 321
 322 static void on_consumer_frame_show( mlt_properties owner, mlt_consumer consumer, mlt_frame frame )
 323 {
 324         if ( frame )
 325                 consumer->position = mlt_frame_get_position( frame );
 326 }
 327
 328 /** Create a new consumer.
 329  *
 330  * \public \memberof mlt_consumer_s
 331  * \param profile a profile (optional, but recommended)
 332  * \return a new consumer
 333  */
 334
 335 mlt_consumer mlt_consumer_new( mlt_profile profile )
 336 {
 337         // Create the memory for the structure
 338         mlt_consumer self = malloc( sizeof( struct mlt_consumer_s ) );
 339
 340         // Initialise it
 341         if ( self != NULL && mlt_consumer_init( self, NULL, profile ) == 0 )
 342         {
 343                 // Return it
 344                 return self;
 345         }
 346         else
 347         {
 348                 free(self);
 349                 return NULL;
 350         }
 351 }
 352
 353 /** Get the parent service object.
 354  *
 355  * \public \memberof mlt_consumer_s
 356  * \param self a consumer
 357  * \return the parent service class
 358  * \see MLT_CONSUMER_SERVICE
 359  */
 360
 361 mlt_service mlt_consumer_service( mlt_consumer self )
 362 {
 363         return self != NULL ? &self->parent : NULL;
 364 }
 365
 366 /** Get the consumer properties.
 367  *
 368  * \public \memberof mlt_consumer_s
 369  * \param self a consumer
 370  * \return the consumer's properties list
 371  * \see MLT_CONSUMER_PROPERTIES
 372  */
 373
 374 mlt_properties mlt_consumer_properties( mlt_consumer self )
 375 {
 376         return self != NULL ? MLT_SERVICE_PROPERTIES( &self->parent ) : NULL;
 377 }
 378
 379 /** Connect the consumer to the producer.
 380  *
 381  * \public \memberof mlt_consumer_s
 382  * \param self a consumer
 383  * \param producer a producer
 384  * \return > 0 warning, == 0 success, < 0 serious error,
 385  *         1 = this service does not accept input,
 386  *         2 = the producer is invalid,
 387  *         3 = the producer is already registered with this consumer
 388  */
 389
 390 int mlt_consumer_connect( mlt_consumer self, mlt_service producer )
 391 {
 392         return mlt_service_connect_producer( &self->parent, producer, 0 );
 393 }
 394
 395 /** Start the consumer.
 396  *
 397  * \public \memberof mlt_consumer_s
 398  * \param self a consumer
 399  * \return true if there was an error
 400  */
 401
 402 int mlt_consumer_start( mlt_consumer self )
 403 {
 404         if ( !mlt_consumer_is_stopped( self ) )
 405                 return 0;
 406
 407         // Stop listening to the property-changed event
 408         mlt_event_block( self->event_listener );
 409
 410         // Get the properies
 411         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 412
 413         // Determine if there's a test card producer
 414         char *test_card = mlt_properties_get( properties, "test_card" );
 415
 416         // Just to make sure nothing is hanging around...
 417         pthread_mutex_lock( &self->put_mutex );
 418         self->put = NULL;
 419         self->put_active = 1;
 420         pthread_mutex_unlock( &self->put_mutex );
 421
 422         // Deal with it now.
 423         if ( test_card != NULL )
 424         {
 425                 if ( mlt_properties_get_data( properties, "test_card_producer", NULL ) == NULL )
 426                 {
 427                         // Create a test card producer
 428                         mlt_profile profile = mlt_service_profile( MLT_CONSUMER_SERVICE( self ) );
 429                         mlt_producer producer = mlt_factory_producer( profile, NULL, test_card );
 430
 431                         // Do we have a producer
 432                         if ( producer != NULL )
 433                         {
 434                                 // Test card should loop I guess...
 435                                 mlt_properties_set( MLT_PRODUCER_PROPERTIES( producer ), "eof", "loop" );
 436                                 //mlt_producer_set_speed( producer, 0 );
 437                                 //mlt_producer_set_in_and_out( producer, 0, 0 );
 438
 439                                 // Set the test card on the consumer
 440                                 mlt_properties_set_data( properties, "test_card_producer", producer, 0, ( mlt_destructor )mlt_producer_close, NULL );
 441                         }
 442                 }
 443         }
 444         else
 445         {
 446                 // Allow the hash table to speed things up
 447                 mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
 448         }
 449
 450         // Set the frame duration in microseconds for the frame-dropping heuristic
 451         int frame_duration = 1000000 / mlt_properties_get_int( properties, "frame_rate_num" ) *
 452                         mlt_properties_get_int( properties, "frame_rate_den" );
 453         mlt_properties_set_int( properties, "frame_duration", frame_duration );
 454
 455         // Check and run an ante command
 456         if ( mlt_properties_get( properties, "ante" ) )
 457                 if ( system( mlt_properties_get( properties, "ante" ) ) == -1 )
 458                         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_ERROR, "system(%s) failed!\n", mlt_properties_get( properties, "ante" ) );
 459
 460         // Set the real_time preference
 461         self->real_time = mlt_properties_get_int( properties, "real_time" );
 462
 463         // For worker threads implementation, buffer must be at least # threads
 464         if ( abs( self->real_time ) > 1 && mlt_properties_get_int( properties, "buffer" ) <= abs( self->real_time ) )
 465                 mlt_properties_set_int( properties, "_buffer", abs( self->real_time ) + 1 );
 466
 467         // Get the image format to use for rendering threads
 468         const char* format = mlt_properties_get( properties, "mlt_image_format" );
 469         if ( format )
 470         {
 471                 if ( !strcmp( format, "rgb24" ) )
 472                         self->format = mlt_image_rgb24;
 473                 else if ( !strcmp( format, "rgb24a" ) )
 474                         self->format = mlt_image_rgb24a;
 475                 else if ( !strcmp( format, "yuv420p" ) )
 476                         self->format = mlt_image_yuv420p;
 477                 else if ( !strcmp( format, "none" ) )
 478                         self->format = mlt_image_none;
 479                 else
 480                         self->format = mlt_image_yuv422;
 481         }
 482
 483         // Start the service
 484         if ( self->start != NULL )
 485                 return self->start( self );
 486
 487         return 0;
 488 }
 489
 490 /** An alternative method to feed frames into the consumer.
 491  *
 492  * Only valid if the consumer itself is not connected.
 493  *
 494  * \public \memberof mlt_consumer_s
 495  * \param self a consumer
 496  * \param frame a frame
 497  * \return true (ignore self for now)
 498  */
 499
 500 int mlt_consumer_put_frame( mlt_consumer self, mlt_frame frame )
 501 {
 502         int error = 1;
 503
 504         // Get the service assoicated to the consumer
 505         mlt_service service = MLT_CONSUMER_SERVICE( self );
 506
 507         if ( mlt_service_producer( service ) == NULL )
 508         {
 509                 struct timeval now;
 510                 struct timespec tm;
 511                 pthread_mutex_lock( &self->put_mutex );
 512                 while ( self->put_active && self->put != NULL )
 513                 {
 514                         gettimeofday( &now, NULL );
 515                         tm.tv_sec = now.tv_sec + 1;
 516                         tm.tv_nsec = now.tv_usec * 1000;
 517                         pthread_cond_timedwait( &self->put_cond, &self->put_mutex, &tm );
 518                 }
 519                 if ( self->put_active && self->put == NULL )
 520                         self->put = frame;
 521                 else
 522                         mlt_frame_close( frame );
 523                 pthread_cond_broadcast( &self->put_cond );
 524                 pthread_mutex_unlock( &self->put_mutex );
 525         }
 526         else
 527         {
 528                 mlt_frame_close( frame );
 529         }
 530
 531         return error;
 532 }
 533
 534 /** Protected method for consumer to get frames from connected service
 535  *
 536  * \public \memberof mlt_consumer_s
 537  * \param self a consumer
 538  * \return a frame
 539  */
 540
 541 mlt_frame mlt_consumer_get_frame( mlt_consumer self )
 542 {
 543         // Frame to return
 544         mlt_frame frame = NULL;
 545
 546         // Get the service assoicated to the consumer
 547         mlt_service service = MLT_CONSUMER_SERVICE( self );
 548
 549         // Get the consumer properties
 550         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 551
 552         // Get the frame
 553         if ( mlt_service_producer( service ) == NULL && mlt_properties_get_int( properties, "put_mode" ) )
 554         {
 555                 struct timeval now;
 556                 struct timespec tm;
 557                 pthread_mutex_lock( &self->put_mutex );
 558                 while ( self->put_active && self->put == NULL )
 559                 {
 560                         gettimeofday( &now, NULL );
 561                         tm.tv_sec = now.tv_sec + 1;
 562                         tm.tv_nsec = now.tv_usec * 1000;
 563                         pthread_cond_timedwait( &self->put_cond, &self->put_mutex, &tm );
 564                 }
 565                 frame = self->put;
 566                 self->put = NULL;
 567                 pthread_cond_broadcast( &self->put_cond );
 568                 pthread_mutex_unlock( &self->put_mutex );
 569                 if ( frame != NULL )
 570                         mlt_service_apply_filters( service, frame, 0 );
 571         }
 572         else if ( mlt_service_producer( service ) != NULL )
 573         {
 574                 mlt_service_get_frame( service, &frame, 0 );
 575         }
 576         else
 577         {
 578                 frame = mlt_frame_init( service );
 579         }
 580
 581         if ( frame != NULL )
 582         {
 583                 // Get the frame properties
 584                 mlt_properties frame_properties = MLT_FRAME_PROPERTIES( frame );
 585
 586                 // Get the test card producer
 587                 mlt_producer test_card = mlt_properties_get_data( properties, "test_card_producer", NULL );
 588
 589                 // Attach the test frame producer to it.
 590                 if ( test_card != NULL )
 591                         mlt_properties_set_data( frame_properties, "test_card_producer", test_card, 0, NULL, NULL );
 592
 593                 // Pass along the interpolation and deinterlace options
 594                 // TODO: get rid of consumer_deinterlace and use profile.progressive
 595                 mlt_properties_set( frame_properties, "rescale.interp", mlt_properties_get( properties, "rescale" ) );
 596                 mlt_properties_set_int( frame_properties, "consumer_deinterlace", mlt_properties_get_int( properties, "progressive" ) | mlt_properties_get_int( properties, "deinterlace" ) );
 597                 mlt_properties_set( frame_properties, "deinterlace_method", mlt_properties_get( properties, "deinterlace_method" ) );
 598                 mlt_properties_set_int( frame_properties, "consumer_tff", mlt_properties_get_int( properties, "top_field_first" ) );
 599         }
 600
 601         // Return the frame
 602         return frame;
 603 }
 604
 605 /** Compute the time difference between now and a time value.
 606  *
 607  * \private \memberof mlt_consumer_s
 608  * \param time1 a time value to be compared against now
 609  * \return the difference in microseconds
 610  */
 611
 612 static inline long time_difference( struct timeval *time1 )
 613 {
 614         struct timeval time2;
 615         time2.tv_sec = time1->tv_sec;
 616         time2.tv_usec = time1->tv_usec;
 617         gettimeofday( time1, NULL );
 618         return time1->tv_sec * 1000000 + time1->tv_usec - time2.tv_sec * 1000000 - time2.tv_usec;
 619 }
 620
 621 /** The thread procedure for asynchronously pulling frames through the service
 622  * network connected to a consumer.
 623  *
 624  * \private \memberof mlt_consumer_s
 625  * \param arg a consumer
 626  */
 627
 628 static void *consumer_read_ahead_thread( void *arg )
 629 {
 630         // The argument is the consumer
 631         mlt_consumer self = arg;
 632
 633         // Get the properties of the consumer
 634         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 635
 636         // Get the width and height
 637         int width = mlt_properties_get_int( properties, "width" );
 638         int height = mlt_properties_get_int( properties, "height" );
 639
 640         // See if video is turned off
 641         int video_off = mlt_properties_get_int( properties, "video_off" );
 642         int preview_off = mlt_properties_get_int( properties, "preview_off" );
 643         int preview_format = mlt_properties_get_int( properties, "preview_format" );
 644
 645         // Get the audio settings
 646         mlt_audio_format afmt = mlt_audio_s16;
 647         const char *format = mlt_properties_get( properties, "mlt_audio_format" );
 648         if ( format )
 649         {
 650                 if ( !strcmp( format, "none" ) )
 651                         afmt = mlt_audio_none;
 652                 else if ( !strcmp( format, "s32" ) )
 653                         afmt = mlt_audio_s32;
 654                 else if ( !strcmp( format, "s32le" ) )
 655                         afmt = mlt_audio_s32le;
 656                 else if ( !strcmp( format, "float" ) )
 657                         afmt = mlt_audio_float;
 658                 else if ( !strcmp( format, "f32le" ) )
 659                         afmt = mlt_audio_f32le;
 660         }
 661         int counter = 0;
 662         double fps = mlt_properties_get_double( properties, "fps" );
 663         int channels = mlt_properties_get_int( properties, "channels" );
 664         int frequency = mlt_properties_get_int( properties, "frequency" );
 665         int samples = 0;
 666         void *audio = NULL;
 667
 668         // See if audio is turned off
 669         int audio_off = mlt_properties_get_int( properties, "audio_off" );
 670
 671         // Get the maximum size of the buffer
 672         int buffer = mlt_properties_get_int( properties, "buffer" ) + 1;
 673
 674         // General frame variable
 675         mlt_frame frame = NULL;
 676         uint8_t *image = NULL;
 677
 678         // Time structures
 679         struct timeval ante;
 680
 681         // Average time for get_frame and get_image
 682         int count = 0;
 683         int skipped = 0;
 684         int64_t time_process = 0;
 685         int skip_next = 0;
 686         mlt_position pos = 0;
 687         mlt_position start_pos = 0;
 688         mlt_position last_pos = 0;
 689         int frame_duration = mlt_properties_get_int( properties, "frame_duration" );
 690         int drop_max = mlt_properties_get_int( properties, "drop_max" );
 691
 692         if ( preview_off && preview_format != 0 )
 693                 self->format = preview_format;
 694
 695         // Get the first frame
 696         frame = mlt_consumer_get_frame( self );
 697
 698         if ( frame )
 699         {
 700                 // Get the image of the first frame
 701                 if ( !video_off )
 702                 {
 703                         mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 704                         mlt_frame_get_image( frame, &image, &self->format, &width, &height, 0 );
 705                 }
 706
 707                 if ( !audio_off )
 708                 {
 709                         samples = mlt_sample_calculator( fps, frequency, counter++ );
 710                         mlt_frame_get_audio( frame, &audio, &afmt, &frequency, &channels, &samples );
 711                 }
 712
 713                 // Mark as rendered
 714                 mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 715                 last_pos = start_pos = pos = mlt_frame_get_position( frame );
 716         }
 717
 718         // Get the starting time (can ignore the times above)
 719         gettimeofday( &ante, NULL );
 720
 721         // Continue to read ahead
 722         while ( self->ahead )
 723         {
 724                 // Put the current frame into the queue
 725                 pthread_mutex_lock( &self->queue_mutex );
 726                 while( self->ahead && mlt_deque_count( self->queue ) >= buffer )
 727                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
 728                 mlt_deque_push_back( self->queue, frame );
 729                 pthread_cond_broadcast( &self->queue_cond );
 730                 pthread_mutex_unlock( &self->queue_mutex );
 731
 732                 // Get the next frame
 733                 frame = mlt_consumer_get_frame( self );
 734
 735                 // If there's no frame, we're probably stopped...
 736                 if ( frame == NULL )
 737                         continue;
 738                 pos = mlt_frame_get_position( frame );
 739
 740                 // Increment the counter used for averaging processing cost
 741                 count ++;
 742
 743                 // All non-normal playback frames should be shown
 744                 if ( mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "_speed" ) != 1 )
 745                 {
 746 #ifdef DEINTERLACE_ON_NOT_NORMAL_SPEED
 747                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "consumer_deinterlace", 1 );
 748 #endif
 749                         // Indicate seeking or trick-play
 750                         start_pos = pos;
 751                 }
 752
 753                 // If skip flag not set or frame-dropping disabled
 754                 if ( !skip_next || self->real_time == -1 )
 755                 {
 756                         if ( !video_off )
 757                         {
 758                                 // Reset width/height - could have been changed by previous mlt_frame_get_image
 759                                 width = mlt_properties_get_int( properties, "width" );
 760                                 height = mlt_properties_get_int( properties, "height" );
 761
 762                                 // Get the image
 763                                 mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 764                                 mlt_frame_get_image( frame, &image, &self->format, &width, &height, 0 );
 765                         }
 766
 767                         // Indicate the rendered image is available.
 768                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 769
 770                         // Reset consecutively-skipped counter
 771                         skipped = 0;
 772                 }
 773                 else // Skip image processing
 774                 {
 775                         // Increment the number of consecutively-skipped frames
 776                         skipped++;
 777
 778                         // If too many (1 sec) consecutively-skipped frames
 779                         if ( skipped > drop_max )
 780                         {
 781                                 // Reset cost tracker
 782                                 time_process = 0;
 783                                 count = 1;
 784                                 mlt_log_verbose( self, "too many frames dropped - forcing next frame\n" );
 785                         }
 786                 }
 787
 788                 // Always process audio
 789                 if ( !audio_off )
 790                 {
 791                         samples = mlt_sample_calculator( fps, frequency, counter++ );
 792                         mlt_frame_get_audio( frame, &audio, &afmt, &frequency, &channels, &samples );
 793                 }
 794
 795                 // Get the time to process this frame
 796                 int64_t time_current = time_difference( &ante );
 797
 798                 // If the current time is not suddenly some large amount
 799                 if ( time_current < time_process / count * 20 || !time_process || count < 5 )
 800                 {
 801                         // Accumulate the cost for processing this frame
 802                         time_process += time_current;
 803                 }
 804                 else
 805                 {
 806                         mlt_log_debug( self, "current %"PRId64" threshold %"PRId64" count %d\n",
 807                                 time_current, (int64_t) (time_process / count * 20), count );
 808                         // Ignore the cost of this frame's time
 809                         count--;
 810                 }
 811
 812                 // Determine if we started, resumed, or seeked
 813                 if ( pos != last_pos + 1 )
 814                         start_pos = pos;
 815                 last_pos = pos;
 816
 817                 // Do not skip the first 20% of buffer at start, resume, or seek
 818                 if ( pos - start_pos <= buffer / 5 + 1 )
 819                 {
 820                         // Reset cost tracker
 821                         time_process = 0;
 822                         count = 1;
 823                 }
 824
 825                 // Reset skip flag
 826                 skip_next = 0;
 827
 828                 // Only consider skipping if the buffer level is low (or really small)
 829                 if ( mlt_deque_count( self->queue ) <= buffer / 5 + 1 )
 830                 {
 831                         // Skip next frame if average cost exceeds frame duration.
 832                         if ( time_process / count > frame_duration )
 833                                 skip_next = 1;
 834                         if ( skip_next )
 835                                 mlt_log_debug( self, "avg usec %"PRId64" (%"PRId64"/%d) duration %d\n",
 836                                         time_process/count, time_process, count, frame_duration);
 837                 }
 838         }
 839
 840         // Remove the last frame
 841         mlt_frame_close( frame );
 842
 843         return NULL;
 844 }
 845
 846 /** Locate the first unprocessed frame in the queue.
 847  *
 848  * When playing with realtime behavior, we do not use the true head, but
 849  * rather an adjusted process_head. The process_head is adjusted based on
 850  * the rate of frame-dropping or recovery from frame-dropping. The idea is
 851  * that as the level of frame-dropping increases to move the process_head
 852  * closer to the tail because the frames are not completing processing prior
 853  * to their playout! Then, as frames are not dropped the process_head moves
 854  * back closer to the head of the queue so that worker threads can work
 855  * ahead of the playout point (queue head).
 856  *
 857  * \private \memberof mlt_consumer_s
 858  * \param self a consumer
 859  * \return an index into the queue
 860  */
 861
 862 static inline int first_unprocessed_frame( mlt_consumer self )
 863 {
 864         int index = self->real_time <= 0 ? 0 : self->process_head;
 865         while ( index < mlt_deque_count( self->queue ) && MLT_FRAME( mlt_deque_peek( self->queue, index ) )->is_processing )
 866                 index++;
 867         return index;
 868 }
 869
 870 /** The worker thread procedure for parallel processing frames.
 871  *
 872  * \private \memberof mlt_consumer_s
 873  * \param arg a consumer
 874  */
 875
 876 static void *consumer_worker_thread( void *arg )
 877 {
 878         // The argument is the consumer
 879         mlt_consumer self = arg;
 880
 881         // Get the properties of the consumer
 882         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
 883
 884         // Get the width and height
 885         int width = mlt_properties_get_int( properties, "width" );
 886         int height = mlt_properties_get_int( properties, "height" );
 887         mlt_image_format format = self->format;
 888
 889         // See if video is turned off
 890         int video_off = mlt_properties_get_int( properties, "video_off" );
 891         int preview_off = mlt_properties_get_int( properties, "preview_off" );
 892         int preview_format = mlt_properties_get_int( properties, "preview_format" );
 893
 894         // General frame variable
 895         mlt_frame frame = NULL;
 896         uint8_t *image = NULL;
 897
 898         if ( preview_off && preview_format != 0 )
 899                 format = preview_format;
 900
 901         // Continue to read ahead
 902         while ( self->ahead )
 903         {
 904                 // Get the next unprocessed frame from the work queue
 905                 pthread_mutex_lock( &self->queue_mutex );
 906                 int index = first_unprocessed_frame( self );
 907                 while ( self->ahead && index >= mlt_deque_count( self->queue ) )
 908                 {
 909                         mlt_log_debug( MLT_CONSUMER_SERVICE(self), "waiting in worker index = %d queue count = %d\n",
 910                                 index, mlt_deque_count( self->queue ) );
 911                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
 912                         index = first_unprocessed_frame( self );
 913                 }
 914
 915                 // Mark the frame for processing
 916                 frame = mlt_deque_peek( self->queue, index );
 917                 if ( frame )
 918                 {
 919                         mlt_log_debug( MLT_CONSUMER_SERVICE(self), "worker processing index = %d frame %d queue count = %d\n",
 920                                 index, mlt_frame_get_position(frame), mlt_deque_count( self->queue ) );
 921                         frame->is_processing = 1;
 922                         mlt_properties_inc_ref( MLT_FRAME_PROPERTIES( frame ) );
 923                 }
 924                 pthread_mutex_unlock( &self->queue_mutex );
 925
 926                 // If there's no frame, we're probably stopped...
 927                 if ( frame == NULL )
 928                         continue;
 929
 930 #ifdef DEINTERLACE_ON_NOT_NORMAL_SPEED
 931                 // All non normal playback frames should be shown
 932                 if ( mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "_speed" ) != 1 )
 933                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "consumer_deinterlace", 1 );
 934 #endif
 935
 936                 // Get the image
 937                 if ( !video_off )
 938                 {
 939                         // Fetch width/height again
 940                         width = mlt_properties_get_int( properties, "width" );
 941                         height = mlt_properties_get_int( properties, "height" );
 942                         mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-frame-render", frame, NULL );
 943                         mlt_frame_get_image( frame, &image, &format, &width, &height, 0 );
 944                 }
 945                 mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
 946                 mlt_frame_close( frame );
 947
 948                 // Tell a waiting thread (non-realtime main consumer thread) that we are done.
 949                 pthread_mutex_lock( &self->done_mutex );
 950                 pthread_cond_broadcast( &self->done_cond );
 951                 pthread_mutex_unlock( &self->done_mutex );
 952         }
 953
 954         return NULL;
 955 }
 956
 957 /** Start the read/render thread.
 958  *
 959  * \private \memberof mlt_consumer_s
 960  * \param self a consumer
 961  */
 962
 963 static void consumer_read_ahead_start( mlt_consumer self )
 964 {
 965         // We're running now
 966         self->ahead = 1;
 967
 968         // Create the frame queue
 969         self->queue = mlt_deque_init( );
 970
 971         // Create the queue mutex
 972         pthread_mutex_init( &self->queue_mutex, NULL );
 973
 974         // Create the condition
 975         pthread_cond_init( &self->queue_cond, NULL );
 976
 977         // Create the read ahead
 978         if ( mlt_properties_get( MLT_CONSUMER_PROPERTIES( self ), "priority" ) )
 979         {
 980                 struct sched_param priority;
 981                 priority.sched_priority = mlt_properties_get_int( MLT_CONSUMER_PROPERTIES( self ), "priority" );
 982                 pthread_attr_t thread_attributes;
 983                 pthread_attr_init( &thread_attributes );
 984                 pthread_attr_setschedpolicy( &thread_attributes, SCHED_OTHER );
 985                 pthread_attr_setschedparam( &thread_attributes, &priority );
 986                 pthread_attr_setinheritsched( &thread_attributes, PTHREAD_EXPLICIT_SCHED );
 987                 pthread_attr_setscope( &thread_attributes, PTHREAD_SCOPE_SYSTEM );
 988                 if ( pthread_create( &self->ahead_thread, &thread_attributes, consumer_read_ahead_thread, self ) < 0 )
 989                         pthread_create( &self->ahead_thread, NULL, consumer_read_ahead_thread, self );
 990                 pthread_attr_destroy( &thread_attributes );
 991         }
 992         else
 993         {
 994                 pthread_create( &self->ahead_thread, NULL, consumer_read_ahead_thread, self );
 995         }
 996         self->started = 1;
 997 }
 998
 999 /** Start the worker threads.
1000  *
1001  * \private \memberof mlt_consumer_s
1002  * \param self a consumer
1003  */
1004
1005 static void consumer_work_start( mlt_consumer self )
1006 {
1007         int n = abs( self->real_time );
1008         pthread_t *thread = calloc( 1, sizeof( pthread_t ) * n );
1009
1010         // We're running now
1011         self->ahead = 1;
1012         self->threads = thread;
1013
1014         // These keep track of the accelleration of frame dropping or recovery.
1015         self->consecutive_dropped = 0;
1016         self->consecutive_rendered = 0;
1017
1018         // This is the position in the queue from which to look for a frame to process.
1019         // If we always start from the head, then we may likely not complete processing
1020         // before the frame is played out.
1021         self->process_head = 0;
1022
1023         // Create the queues
1024         self->queue = mlt_deque_init();
1025         self->worker_threads = mlt_deque_init();
1026
1027         // Create the mutexes
1028         pthread_mutex_init( &self->queue_mutex, NULL );
1029         pthread_mutex_init( &self->done_mutex, NULL );
1030
1031         // Create the conditions
1032         pthread_cond_init( &self->queue_cond, NULL );
1033         pthread_cond_init( &self->done_cond, NULL );
1034
1035         // Create the read ahead
1036         if ( mlt_properties_get( MLT_CONSUMER_PROPERTIES( self ), "priority" ) )
1037         {
1038
1039                 struct sched_param priority;
1040                 pthread_attr_t thread_attributes;
1041
1042                 priority.sched_priority = mlt_properties_get_int( MLT_CONSUMER_PROPERTIES( self ), "priority" );
1043                 pthread_attr_init( &thread_attributes );
1044                 pthread_attr_setschedpolicy( &thread_attributes, SCHED_OTHER );
1045                 pthread_attr_setschedparam( &thread_attributes, &priority );
1046                 pthread_attr_setinheritsched( &thread_attributes, PTHREAD_EXPLICIT_SCHED );
1047                 pthread_attr_setscope( &thread_attributes, PTHREAD_SCOPE_SYSTEM );
1048
1049                 while ( n-- )
1050                 {
1051                         if ( pthread_create( thread, &thread_attributes, consumer_worker_thread, self ) < 0 )
1052                                 if ( pthread_create( thread, NULL, consumer_worker_thread, self ) == 0 )
1053                                         mlt_deque_push_back( self->worker_threads, thread );
1054                         thread++;
1055                 }
1056                 pthread_attr_destroy( &thread_attributes );
1057         }
1058
1059         else
1060         {
1061                 while ( n-- )
1062                 {
1063                         if ( pthread_create( thread, NULL, consumer_worker_thread, self ) == 0 )
1064                                 mlt_deque_push_back( self->worker_threads, thread );
1065                         thread++;
1066                 }
1067         }
1068         self->started = 1;
1069 }
1070
1071 /** Stop the read/render thread.
1072  *
1073  * \private \memberof mlt_consumer_s
1074  * \param self a consumer
1075  */
1076
1077 static void consumer_read_ahead_stop( mlt_consumer self )
1078 {
1079         // Make sure we're running
1080         if ( self->started )
1081         {
1082                 // Inform thread to stop
1083                 self->ahead = 0;
1084
1085                 // Broadcast to the condition in case it's waiting
1086                 pthread_mutex_lock( &self->queue_mutex );
1087                 pthread_cond_broadcast( &self->queue_cond );
1088                 pthread_mutex_unlock( &self->queue_mutex );
1089
1090                 // Broadcast to the put condition in case it's waiting
1091                 pthread_mutex_lock( &self->put_mutex );
1092                 pthread_cond_broadcast( &self->put_cond );
1093                 pthread_mutex_unlock( &self->put_mutex );
1094
1095                 // Join the thread
1096                 pthread_join( self->ahead_thread, NULL );
1097                 self->started = 0;
1098
1099                 // Destroy the frame queue mutex
1100                 pthread_mutex_destroy( &self->queue_mutex );
1101
1102                 // Destroy the condition
1103                 pthread_cond_destroy( &self->queue_cond );
1104
1105                 // Wipe the queue
1106                 while ( mlt_deque_count( self->queue ) )
1107                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1108
1109                 // Close the queue
1110                 mlt_deque_close( self->queue );
1111         }
1112 }
1113
1114 /** Stop the worker threads.
1115  *
1116  * \private \memberof mlt_consumer_s
1117  * \param self a consumer
1118  */
1119
1120 static void consumer_work_stop( mlt_consumer self )
1121 {
1122         // Make sure we're running
1123         if ( self->started )
1124         {
1125                 // Inform thread to stop
1126                 self->ahead = 0;
1127
1128                 // Broadcast to the queue condition in case it's waiting
1129                 pthread_mutex_lock( &self->queue_mutex );
1130                 pthread_cond_broadcast( &self->queue_cond );
1131                 pthread_mutex_unlock( &self->queue_mutex );
1132
1133                 // Broadcast to the put condition in case it's waiting
1134                 pthread_mutex_lock( &self->put_mutex );
1135                 pthread_cond_broadcast( &self->put_cond );
1136                 pthread_mutex_unlock( &self->put_mutex );
1137
1138                 // Broadcast to the done condition in case it's waiting
1139                 pthread_mutex_lock( &self->done_mutex );
1140                 pthread_cond_broadcast( &self->done_cond );
1141                 pthread_mutex_unlock( &self->done_mutex );
1142
1143                 // Join the threads
1144                 pthread_t *thread;
1145                 while ( ( thread = mlt_deque_pop_back( self->worker_threads ) ) )
1146                         pthread_join( *thread, NULL );
1147
1148                 // Deallocate the array of threads
1149                 if ( self->threads )
1150                         free( self->threads );
1151
1152                 // Indicate that worker threads no longer running
1153                 self->started = 0;
1154
1155                 // Destroy the mutexes
1156                 pthread_mutex_destroy( &self->queue_mutex );
1157                 pthread_mutex_destroy( &self->done_mutex );
1158
1159                 // Destroy the conditions
1160                 pthread_cond_destroy( &self->queue_cond );
1161                 pthread_cond_destroy( &self->done_cond );
1162
1163                 // Wipe the queues
1164                 while ( mlt_deque_count( self->queue ) )
1165                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1166
1167                 // Close the queues
1168                 mlt_deque_close( self->queue );
1169                 mlt_deque_close( self->worker_threads );
1170         }
1171 }
1172
1173 /** Flush the read/render thread's buffer.
1174  *
1175  * \public \memberof mlt_consumer_s
1176  * \param self a consumer
1177  */
1178
1179 void mlt_consumer_purge( mlt_consumer self )
1180 {
1181         if ( self->ahead )
1182         {
1183                 pthread_mutex_lock( &self->queue_mutex );
1184                 while ( mlt_deque_count( self->queue ) )
1185                         mlt_frame_close( mlt_deque_pop_back( self->queue ) );
1186                 pthread_cond_broadcast( &self->queue_cond );
1187                 pthread_mutex_unlock( &self->queue_mutex );
1188         }
1189 }
1190
1191 /** Use multiple worker threads and a work queue.
1192  */
1193
1194 static mlt_frame worker_get_frame( mlt_consumer self, mlt_properties properties )
1195 {
1196         // Frame to return
1197         mlt_frame frame = NULL;
1198
1199         double fps = mlt_properties_get_double( properties, "fps" );
1200         int threads = abs( self->real_time );
1201         int buffer = mlt_properties_get_int( properties, "_buffer" );
1202         buffer = buffer > 0 ? buffer : mlt_properties_get_int( properties, "buffer" );
1203         // This is a heuristic to determine a suitable minimum buffer size for the number of threads.
1204         int headroom = 2 + threads * threads;
1205         buffer = buffer < headroom ? headroom : buffer;
1206
1207         // Start worker threads if not already started.
1208         if ( ! self->ahead )
1209         {
1210                 int prefill = mlt_properties_get_int( properties, "prefill" );
1211                 prefill = prefill > 0 && prefill < buffer ? prefill : buffer;
1212
1213                 consumer_work_start( self );
1214
1215                 // Fill the work queue.
1216                 int i = buffer;
1217                 while ( self->ahead && i-- )
1218                 {
1219                         frame = mlt_consumer_get_frame( self );
1220                         if ( frame )
1221                         {
1222                                 pthread_mutex_lock( &self->queue_mutex );
1223                                 mlt_deque_push_back( self->queue, frame );
1224                                 pthread_cond_signal( &self->queue_cond );
1225                                 pthread_mutex_unlock( &self->queue_mutex );
1226                         }
1227                 }
1228
1229                 // Wait for prefill
1230                 while ( self->ahead && first_unprocessed_frame( self ) < prefill )
1231                 {
1232                         pthread_mutex_lock( &self->done_mutex );
1233                         pthread_cond_wait( &self->done_cond, &self->done_mutex );
1234                         pthread_mutex_unlock( &self->done_mutex );
1235                 }
1236                 self->process_head = threads;
1237         }
1238
1239 //      mlt_log_verbose( MLT_CONSUMER_SERVICE(self), "size %d done count %d work count %d process_head %d\n",
1240 //              threads, first_unprocessed_frame( self ), mlt_deque_count( self->queue ), self->process_head );
1241
1242         // Feed the work queue
1243         while ( self->ahead && mlt_deque_count( self->queue ) < buffer )
1244         {
1245                 frame = mlt_consumer_get_frame( self );
1246                 if ( ! frame )
1247                         return frame;
1248                 pthread_mutex_lock( &self->queue_mutex );
1249                 mlt_deque_push_back( self->queue, frame );
1250                 pthread_cond_signal( &self->queue_cond );
1251                 pthread_mutex_unlock( &self->queue_mutex );
1252         }
1253
1254         // Wait if not realtime.
1255         mlt_frame head_frame = MLT_FRAME( mlt_deque_peek_front( self->queue ) );
1256         while ( self->ahead && self->real_time < 0 &&
1257                 !( head_frame && mlt_properties_get_int( MLT_FRAME_PROPERTIES( head_frame ), "rendered" ) ) )
1258         {
1259                 pthread_mutex_lock( &self->done_mutex );
1260                 pthread_cond_wait( &self->done_cond, &self->done_mutex );
1261                 pthread_mutex_unlock( &self->done_mutex );
1262         }
1263
1264         // Get the frame from the queue.
1265         pthread_mutex_lock( &self->queue_mutex );
1266         frame = mlt_deque_pop_front( self->queue );
1267         pthread_mutex_unlock( &self->queue_mutex );
1268
1269         // Adapt the worker process head to the runtime conditions.
1270         if ( self->real_time > 0 )
1271         {
1272                 if ( frame && mlt_properties_get_int( MLT_FRAME_PROPERTIES( frame ), "rendered" ) )
1273                 {
1274                         self->consecutive_dropped = 0;
1275                         if ( self->process_head > threads && self->consecutive_rendered >= self->process_head )
1276                                 self->process_head--;
1277                         else
1278                                 self->consecutive_rendered++;
1279                 }
1280                 else
1281                 {
1282                         self->consecutive_rendered = 0;
1283                         if ( self->process_head < buffer - threads && self->consecutive_dropped > threads )
1284                                 self->process_head++;
1285                         else
1286                                 self->consecutive_dropped++;
1287                 }
1288 //              mlt_log_verbose( MLT_CONSUMER_SERVICE(self), "dropped %d rendered %d process_head %d\n",
1289 //                      self->consecutive_dropped, self->consecutive_rendered, self->process_head );
1290
1291                 // Check for too many consecutively dropped frames
1292                 if ( self->consecutive_dropped > mlt_properties_get_int( properties, "drop_max" ) )
1293                 {
1294                         int orig_buffer = mlt_properties_get_int( properties, "buffer" );
1295                         int prefill = mlt_properties_get_int( properties, "prefill" );
1296                         mlt_log_verbose( self, "too many frames dropped - " );
1297
1298                         // If using a default low-latency buffer level (SDL) and below the limit
1299                         if ( ( orig_buffer == 1 || prefill == 1 ) && buffer < (threads + 1) * 10 )
1300                         {
1301                                 // Auto-scale the buffer to compensate
1302                                 mlt_log_verbose( self, "increasing buffer to %d\n", buffer + threads );
1303                                 mlt_properties_set_int( properties, "_buffer", buffer + threads );
1304                                 self->consecutive_dropped = fps / 2;
1305                         }
1306                         else
1307                         {
1308                                 // Tell the consumer to render it
1309                                 mlt_log_verbose( self, "forcing next frame\n" );
1310                                 mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
1311                                 self->consecutive_dropped = 0;
1312                         }
1313                 }
1314         }
1315
1316         return frame;
1317 }
1318
1319 /** Get the next frame from the producer connected to a consumer.
1320  *
1321  * Typically, one uses this instead of \p mlt_consumer_get_frame to make
1322  * the asynchronous/real-time behavior configurable at runtime.
1323  * You should close the frame returned from this when you are done with it.
1324  *
1325  * \public \memberof mlt_consumer_s
1326  * \param self a consumer
1327  * \return a frame
1328  */
1329
1330 mlt_frame mlt_consumer_rt_frame( mlt_consumer self )
1331 {
1332         // Frame to return
1333         mlt_frame frame = NULL;
1334
1335         // Get the properties
1336         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
1337
1338         // Check if the user has requested real time or not
1339         if ( self->real_time > 1 || self->real_time < -1 )
1340         {
1341                 // see above
1342                 return worker_get_frame( self, properties );
1343         }
1344         else if ( self->real_time == 1 || self->real_time == -1 )
1345         {
1346                 int size = 1;
1347
1348                 // Is the read ahead running?
1349                 if ( self->ahead == 0 )
1350                 {
1351                         int buffer = mlt_properties_get_int( properties, "buffer" );
1352                         int prefill = mlt_properties_get_int( properties, "prefill" );
1353                         consumer_read_ahead_start( self );
1354                         if ( buffer > 1 )
1355                                 size = prefill > 0 && prefill < buffer ? prefill : buffer;
1356                 }
1357
1358                 // Get frame from queue
1359                 pthread_mutex_lock( &self->queue_mutex );
1360                 while( self->ahead && mlt_deque_count( self->queue ) < size )
1361                         pthread_cond_wait( &self->queue_cond, &self->queue_mutex );
1362                 frame = mlt_deque_pop_front( self->queue );
1363                 pthread_cond_broadcast( &self->queue_cond );
1364                 pthread_mutex_unlock( &self->queue_mutex );
1365         }
1366         else // real_time == 0
1367         {
1368                 // Get the frame in non real time
1369                 frame = mlt_consumer_get_frame( self );
1370
1371                 // This isn't true, but from the consumers perspective it is
1372                 if ( frame != NULL )
1373                         mlt_properties_set_int( MLT_FRAME_PROPERTIES( frame ), "rendered", 1 );
1374         }
1375
1376         return frame;
1377 }
1378
1379 /** Callback for the implementation to indicate a stopped condition.
1380  *
1381  * \public \memberof mlt_consumer_s
1382  * \param self a consumer
1383  */
1384
1385 void mlt_consumer_stopped( mlt_consumer self )
1386 {
1387         mlt_properties_set_int( MLT_CONSUMER_PROPERTIES( self ), "running", 0 );
1388         mlt_events_fire( MLT_CONSUMER_PROPERTIES( self ), "consumer-stopped", NULL );
1389         mlt_event_unblock( self->event_listener );
1390 }
1391
1392 /** Stop the consumer.
1393  *
1394  * \public \memberof mlt_consumer_s
1395  * \param self a consumer
1396  * \return true if there was an error
1397  */
1398
1399 int mlt_consumer_stop( mlt_consumer self )
1400 {
1401         // Get the properies
1402         mlt_properties properties = MLT_CONSUMER_PROPERTIES( self );
1403
1404         // Just in case...
1405         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping put waiting\n" );
1406         pthread_mutex_lock( &self->put_mutex );
1407         self->put_active = 0;
1408         pthread_cond_broadcast( &self->put_cond );
1409         pthread_mutex_unlock( &self->put_mutex );
1410
1411         // Stop the consumer
1412         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping consumer\n" );
1413
1414         // Cancel the read ahead threads
1415         self->ahead = 0;
1416         if ( self->started )
1417         {
1418                 // Unblock the consumer calling mlt_consumer_rt_frame
1419                 pthread_mutex_lock( &self->queue_mutex );
1420                 pthread_cond_broadcast( &self->queue_cond );
1421                 pthread_mutex_unlock( &self->queue_mutex );
1422         }
1423
1424         // Invoke the child callback
1425         if ( self->stop != NULL )
1426                 self->stop( self );
1427
1428         // Check if the user has requested real time or not and stop if necessary
1429         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopping read_ahead\n" );
1430         if ( abs( self->real_time ) == 1 )
1431                 consumer_read_ahead_stop( self );
1432         else if ( abs( self->real_time ) > 1 )
1433                 consumer_work_stop( self );
1434
1435         // Kill the test card
1436         mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
1437
1438         // Check and run a post command
1439         if ( mlt_properties_get( properties, "post" ) )
1440                 if (system( mlt_properties_get( properties, "post" ) ) == -1 )
1441                         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_ERROR, "system(%s) failed!\n", mlt_properties_get( properties, "post" ) );
1442
1443         mlt_log( MLT_CONSUMER_SERVICE( self ), MLT_LOG_DEBUG, "stopped\n" );
1444
1445         return 0;
1446 }
1447
1448 /** Determine if the consumer is stopped.
1449  *
1450  * \public \memberof mlt_consumer_s
1451  * \param self a consumer
1452  * \return true if the consumer is stopped
1453  */
1454
1455 int mlt_consumer_is_stopped( mlt_consumer self )
1456 {
1457         // Check if the consumer is stopped
1458         if ( self->is_stopped != NULL )
1459                 return self->is_stopped( self );
1460
1461         return 0;
1462 }
1463
1464 /** Close and destroy the consumer.
1465  *
1466  * \public \memberof mlt_consumer_s
1467  * \param self a consumer
1468  */
1469
1470 void mlt_consumer_close( mlt_consumer self )
1471 {
1472         if ( self != NULL && mlt_properties_dec_ref( MLT_CONSUMER_PROPERTIES( self ) ) <= 0 )
1473         {
1474                 // Get the childs close function
1475                 void ( *consumer_close )( ) = self->close;
1476
1477                 if ( consumer_close )
1478                 {
1479                         // Just in case...
1480                         //mlt_consumer_stop( self );
1481
1482                         self->close = NULL;
1483                         consumer_close( self );
1484                 }
1485                 else
1486                 {
1487                         // Make sure it only gets called once
1488                         self->parent.close = NULL;
1489
1490                         // Destroy the push mutex and condition
1491                         pthread_mutex_destroy( &self->put_mutex );
1492                         pthread_cond_destroy( &self->put_cond );
1493
1494                         mlt_service_close( &self->parent );
1495                 }
1496         }
1497 }
1498
1499 /** Get the position of the last frame shown.
1500  *
1501  * \public \memberof mlt_consumer_s
1502  * \param consumer a consumer
1503  * \return the position
1504  */
1505
1506 mlt_position mlt_consumer_position( mlt_consumer consumer )
1507 {
1508         return consumer->position;
1509 }
1510