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

   1 /*
   2  * mlt_playlist.c -- playlist service class
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include "config.h"
  22
  23 #include "mlt_playlist.h"
  24 #include "mlt_tractor.h"
  25 #include "mlt_field.h"
  26 #include "mlt_frame.h"
  27 #include "mlt_transition.h"
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32
  33 /** Virtual playlist entry.
  34 */
  35
  36 typedef struct playlist_entry_s
  37 {
  38         mlt_producer producer;
  39         mlt_position frame_in;
  40         mlt_position frame_out;
  41         mlt_position frame_count;
  42         mlt_position producer_length;
  43         mlt_event event;
  44         int mix_in_length;
  45         int mix_out_length;
  46         struct playlist_entry_s *mix_in;
  47         struct playlist_entry_s *mix_out;
  48 }
  49 playlist_entry;
  50
  51 /** Private definition.
  52 */
  53
  54 struct mlt_playlist_s
  55 {
  56         struct mlt_producer_s parent;
  57         struct mlt_producer_s blank;
  58
  59         int size;
  60         int count;
  61         playlist_entry **list;
  62 };
  63
  64 /** Forward declarations
  65 */
  66
  67 static int producer_get_frame( mlt_producer producer, mlt_frame_ptr frame, int index );
  68 static int mlt_playlist_unmix( mlt_playlist this, int clip );
  69 static int mlt_playlist_resize_mix( mlt_playlist this, int clip, int in, int out );
  70
  71 /** Constructor.
  72 */
  73
  74 mlt_playlist mlt_playlist_init( )
  75 {
  76         mlt_playlist this = calloc( sizeof( struct mlt_playlist_s ), 1 );
  77         if ( this != NULL )
  78         {
  79                 mlt_producer producer = &this->parent;
  80
  81                 // Construct the producer
  82                 mlt_producer_init( producer, this );
  83
  84                 // Override the producer get_frame
  85                 producer->get_frame = producer_get_frame;
  86
  87                 // Define the destructor
  88                 producer->close = ( mlt_destructor )mlt_playlist_close;
  89                 producer->close_object = this;
  90
  91                 // Initialise blank
  92                 mlt_producer_init( &this->blank, NULL );
  93                 mlt_properties_set( mlt_producer_properties( &this->blank ), "mlt_service", "blank" );
  94                 mlt_properties_set( mlt_producer_properties( &this->blank ), "resource", "blank" );
  95
  96                 // Indicate that this producer is a playlist
  97                 mlt_properties_set_data( mlt_playlist_properties( this ), "playlist", this, 0, NULL, NULL );
  98
  99                 // Specify the eof condition
 100                 mlt_properties_set( mlt_playlist_properties( this ), "eof", "pause" );
 101                 mlt_properties_set( mlt_playlist_properties( this ), "resource", "<playlist>" );
 102                 mlt_properties_set( mlt_playlist_properties( this ), "mlt_type", "mlt_producer" );
 103                 mlt_properties_set_position( mlt_playlist_properties( this ), "in", 0 );
 104                 mlt_properties_set_position( mlt_playlist_properties( this ), "out", 0 );
 105                 mlt_properties_set_position( mlt_playlist_properties( this ), "length", 0 );
 106
 107                 this->size = 10;
 108                 this->list = malloc( this->size * sizeof( playlist_entry * ) );
 109         }
 110
 111         return this;
 112 }
 113
 114 /** Get the producer associated to this playlist.
 115 */
 116
 117 mlt_producer mlt_playlist_producer( mlt_playlist this )
 118 {
 119         return this != NULL ? &this->parent : NULL;
 120 }
 121
 122 /** Get the service associated to this playlist.
 123 */
 124
 125 mlt_service mlt_playlist_service( mlt_playlist this )
 126 {
 127         return mlt_producer_service( &this->parent );
 128 }
 129
 130 /** Get the propertues associated to this playlist.
 131 */
 132
 133 mlt_properties mlt_playlist_properties( mlt_playlist this )
 134 {
 135         return mlt_producer_properties( &this->parent );
 136 }
 137
 138 /** Refresh the playlist after a clip has been changed.
 139 */
 140
 141 static int mlt_playlist_virtual_refresh( mlt_playlist this )
 142 {
 143         // Obtain the properties
 144         mlt_properties properties = mlt_playlist_properties( this );
 145
 146         // Get the fps of the first producer
 147         double fps = mlt_properties_get_double( properties, "first_fps" );
 148         int i = 0;
 149         mlt_position frame_count = 0;
 150
 151         for ( i = 0; i < this->count; i ++ )
 152         {
 153                 // Get the producer
 154                 mlt_producer producer = this->list[ i ]->producer;
 155                 int current_length = mlt_producer_get_out( producer ) - mlt_producer_get_in( producer ) + 1;
 156
 157                 // If fps is 0
 158                 if ( fps == 0 )
 159                 {
 160                         // Inherit it from the producer
 161                         fps = mlt_producer_get_fps( producer );
 162                 }
 163                 else if ( fps != mlt_properties_get_double( mlt_producer_properties( producer ), "fps" ) )
 164                 {
 165                         // Generate a warning for now - the following attempt to fix may fail
 166                         fprintf( stderr, "Warning: fps mismatch on playlist producer %d\n", this->count );
 167
 168                         // It should be safe to impose fps on an image producer, but not necessarily safe for video
 169                         mlt_properties_set_double( mlt_producer_properties( producer ), "fps", fps );
 170                 }
 171
 172                 // Check if the length of the producer has changed
 173                 if ( this->list[ i ]->producer_length != current_length )
 174                 {
 175                         // This clip should be removed...
 176                         if ( this->list[ i ]->frame_in > current_length )
 177                         {
 178                                 this->list[ i ]->frame_count = 0;
 179                                 this->list[ i ]->frame_in = 0;
 180                                 this->list[ i ]->frame_out = 0;
 181                         }
 182                         else if ( this->list[ i ]->frame_out >= current_length )
 183                         {
 184                                 this->list[ i ]->frame_out = current_length - 1;
 185                                 this->list[ i ]->frame_count = this->list[ i ]->frame_out - this->list[ i ]->frame_in + 1;
 186                         }
 187
 188                         // Update the producer_length
 189                         this->list[ i ]->producer_length = current_length;
 190                 }
 191
 192                 // Update the frame_count for this clip
 193                 frame_count += this->list[ i ]->frame_count;
 194         }
 195
 196         // Refresh all properties
 197         mlt_properties_set_double( properties, "first_fps", fps );
 198         mlt_properties_set_double( properties, "fps", fps == 0 ? 25 : fps );
 199         mlt_events_block( properties, properties );
 200         mlt_properties_set_position( properties, "length", frame_count );
 201         mlt_events_unblock( properties, properties );
 202         mlt_properties_set_position( properties, "out", frame_count - 1 );
 203
 204         return 0;
 205 }
 206
 207 /** Listener for producers on the playlist.
 208 */
 209
 210 static void mlt_playlist_listener( mlt_producer producer, mlt_playlist this )
 211 {
 212         mlt_playlist_virtual_refresh( this );
 213 }
 214
 215 /** Append to the virtual playlist.
 216 */
 217
 218 static int mlt_playlist_virtual_append( mlt_playlist this, mlt_producer producer, mlt_position in, mlt_position out )
 219 {
 220         mlt_properties properties = mlt_producer_properties( producer );
 221
 222         // Check that we have room
 223         if ( this->count >= this->size )
 224         {
 225                 int i;
 226                 this->list = realloc( this->list, ( this->size + 10 ) * sizeof( playlist_entry * ) );
 227                 for ( i = this->size; i < this->size + 10; i ++ ) this->list[ i ] = NULL;
 228                 this->size += 10;
 229         }
 230
 231         this->list[ this->count ] = calloc( sizeof( playlist_entry ), 1 );
 232         this->list[ this->count ]->producer = producer;
 233         this->list[ this->count ]->frame_in = in;
 234         this->list[ this->count ]->frame_out = out;
 235         this->list[ this->count ]->frame_count = out - in + 1;
 236         this->list[ this->count ]->producer_length = mlt_producer_get_out( producer ) - mlt_producer_get_in( producer ) + 1;
 237         this->list[ this->count ]->event = mlt_events_listen( properties, this, "producer-changed", ( mlt_listener )mlt_playlist_listener );
 238         mlt_event_inc_ref( this->list[ this->count ]->event );
 239
 240         mlt_properties_set( properties, "eof", "pause" );
 241
 242         mlt_producer_set_speed( producer, 0 );
 243
 244         this->count ++;
 245
 246         mlt_properties_inc_ref( properties );
 247
 248         return mlt_playlist_virtual_refresh( this );
 249 }
 250
 251 /** Seek in the virtual playlist.
 252 */
 253
 254 static mlt_service mlt_playlist_virtual_seek( mlt_playlist this )
 255 {
 256         // Default producer to blank
 257         mlt_producer producer = NULL;
 258
 259         // Map playlist position to real producer in virtual playlist
 260         mlt_position position = mlt_producer_frame( &this->parent );
 261
 262         mlt_position original = position;
 263
 264         // Total number of frames
 265         int64_t total = 0;
 266
 267         // Get the properties
 268         mlt_properties properties = mlt_playlist_properties( this );
 269
 270         // Get the eof handling
 271         char *eof = mlt_properties_get( properties, "eof" );
 272
 273         // Index for the main loop
 274         int i = 0;
 275
 276         // Loop for each producer until found
 277         for ( i = 0; i < this->count; i ++ )
 278         {
 279                 // Increment the total
 280                 total += this->list[ i ]->frame_count;
 281
 282                 // Check if the position indicates that we have found the clip
 283                 if ( position < this->list[ i ]->frame_count )
 284                 {
 285                         // Found it, now break
 286                         producer = this->list[ i ]->producer;
 287                         break;
 288                 }
 289                 else
 290                 {
 291                         // Decrement position by length of this entry
 292                         position -= this->list[ i ]->frame_count;
 293                 }
 294         }
 295
 296         // Seek in real producer to relative position
 297         if ( producer != NULL )
 298         {
 299                 position += this->list[ i ]->frame_in;
 300                 mlt_producer_seek( producer, position );
 301         }
 302         else if ( !strcmp( eof, "pause" ) && total > 0 )
 303         {
 304                 playlist_entry *entry = this->list[ this->count - 1 ];
 305                 mlt_producer this_producer = mlt_playlist_producer( this );
 306                 mlt_producer_seek( this_producer, original - 1 );
 307                 producer = entry->producer;
 308                 mlt_producer_seek( producer, entry->frame_out );
 309                 mlt_producer_set_speed( this_producer, 0 );
 310                 mlt_producer_set_speed( producer, 0 );
 311         }
 312         else if ( !strcmp( eof, "loop" ) && total > 0 )
 313         {
 314                 playlist_entry *entry = this->list[ 0 ];
 315                 mlt_producer this_producer = mlt_playlist_producer( this );
 316                 mlt_producer_seek( this_producer, 0 );
 317                 producer = entry->producer;
 318                 mlt_producer_seek( producer, entry->frame_in );
 319         }
 320         else
 321         {
 322                 producer = &this->blank;
 323         }
 324
 325         return mlt_producer_service( producer );
 326 }
 327
 328 /** Invoked when a producer indicates that it has prematurely reached its end.
 329 */
 330
 331 static mlt_producer mlt_playlist_virtual_set_out( mlt_playlist this )
 332 {
 333         // Default producer to blank
 334         mlt_producer producer = &this->blank;
 335
 336         // Map playlist position to real producer in virtual playlist
 337         mlt_position position = mlt_producer_frame( &this->parent );
 338
 339         // Loop through the virtual playlist
 340         int i = 0;
 341
 342         for ( i = 0; i < this->count; i ++ )
 343         {
 344                 if ( position < this->list[ i ]->frame_count )
 345                 {
 346                         // Found it, now break
 347                         producer = this->list[ i ]->producer;
 348                         break;
 349                 }
 350                 else
 351                 {
 352                         // Decrement position by length of this entry
 353                         position -= this->list[ i ]->frame_count;
 354                 }
 355         }
 356
 357         // Seek in real producer to relative position
 358         if ( i < this->count && this->list[ i ]->frame_out != position )
 359         {
 360                 // Update the frame_count for the changed clip (hmmm)
 361                 this->list[ i ]->frame_out = position;
 362                 this->list[ i ]->frame_count = this->list[ i ]->frame_out - this->list[ i ]->frame_in + 1;
 363
 364                 // Refresh the playlist
 365                 mlt_playlist_virtual_refresh( this );
 366         }
 367
 368         return producer;
 369 }
 370
 371 /** Obtain the current clips index.
 372 */
 373
 374 int mlt_playlist_current_clip( mlt_playlist this )
 375 {
 376         // Map playlist position to real producer in virtual playlist
 377         mlt_position position = mlt_producer_frame( &this->parent );
 378
 379         // Loop through the virtual playlist
 380         int i = 0;
 381
 382         for ( i = 0; i < this->count; i ++ )
 383         {
 384                 if ( position < this->list[ i ]->frame_count )
 385                 {
 386                         // Found it, now break
 387                         break;
 388                 }
 389                 else
 390                 {
 391                         // Decrement position by length of this entry
 392                         position -= this->list[ i ]->frame_count;
 393                 }
 394         }
 395
 396         return i;
 397 }
 398
 399 /** Obtain the current clips producer.
 400 */
 401
 402 mlt_producer mlt_playlist_current( mlt_playlist this )
 403 {
 404         int i = mlt_playlist_current_clip( this );
 405         if ( i < this->count )
 406                 return this->list[ i ]->producer;
 407         else
 408                 return &this->blank;
 409 }
 410
 411 /** Get the position which corresponds to the start of the next clip.
 412 */
 413
 414 mlt_position mlt_playlist_clip( mlt_playlist this, mlt_whence whence, int index )
 415 {
 416         mlt_position position = 0;
 417         int absolute_clip = index;
 418         int i = 0;
 419
 420         // Determine the absolute clip
 421         switch ( whence )
 422         {
 423                 case mlt_whence_relative_start:
 424                         absolute_clip = index;
 425                         break;
 426
 427                 case mlt_whence_relative_current:
 428                         absolute_clip = mlt_playlist_current_clip( this ) + index;
 429                         break;
 430
 431                 case mlt_whence_relative_end:
 432                         absolute_clip = this->count - index;
 433                         break;
 434         }
 435
 436         // Check that we're in a valid range
 437         if ( absolute_clip < 0 )
 438                 absolute_clip = 0;
 439         else if ( absolute_clip > this->count )
 440                 absolute_clip = this->count;
 441
 442         // Now determine the position
 443         for ( i = 0; i < absolute_clip; i ++ )
 444                 position += this->list[ i ]->frame_count;
 445
 446         return position;
 447 }
 448
 449 /** Get all the info about the clip specified.
 450 */
 451
 452 int mlt_playlist_get_clip_info( mlt_playlist this, mlt_playlist_clip_info *info, int index )
 453 {
 454         int error = index < 0 || index >= this->count;
 455         memset( info, 0, sizeof( mlt_playlist_clip_info ) );
 456         if ( !error )
 457         {
 458                 mlt_producer producer = this->list[ index ]->producer;
 459                 mlt_properties properties = mlt_producer_properties( producer );
 460                 info->clip = index;
 461                 info->producer = producer;
 462                 info->start = mlt_playlist_clip( this, mlt_whence_relative_start, index );
 463                 info->resource = mlt_properties_get( properties, "resource" );
 464                 info->frame_in = this->list[ index ]->frame_in;
 465                 info->frame_out = this->list[ index ]->frame_out;
 466                 info->frame_count = this->list[ index ]->frame_count;
 467                 info->length = mlt_producer_get_length( producer );
 468                 info->fps = mlt_producer_get_fps( producer );
 469                 info->event = this->list[ index ]->event;
 470         }
 471
 472         // Determine the consuming filter service
 473         if ( info->producer != NULL )
 474         {
 475                 info->service = mlt_producer_service( info->producer );
 476                 while ( mlt_service_consumer( info->service ) != NULL )
 477                         info->service = mlt_service_consumer( info->service );
 478         }
 479
 480         return error;
 481 }
 482
 483 /** Get number of clips in the playlist.
 484 */
 485
 486 int mlt_playlist_count( mlt_playlist this )
 487 {
 488         return this->count;
 489 }
 490
 491 /** Clear the playlist.
 492 */
 493
 494 int mlt_playlist_clear( mlt_playlist this )
 495 {
 496         int i;
 497         for ( i = 0; i < this->count; i ++ )
 498         {
 499                 mlt_event_close( this->list[ i ]->event );
 500                 mlt_producer_close( this->list[ i ]->producer );
 501         }
 502         this->count = 0;
 503         mlt_properties_set_double( mlt_playlist_properties( this ), "first_fps", 0 );
 504         return mlt_playlist_virtual_refresh( this );
 505 }
 506
 507 /** Append a producer to the playlist.
 508 */
 509
 510 int mlt_playlist_append( mlt_playlist this, mlt_producer producer )
 511 {
 512         // Append to virtual list
 513         return mlt_playlist_virtual_append( this, producer, 0, mlt_producer_get_playtime( producer ) - 1 );
 514 }
 515
 516 /** Append a producer to the playlist with in/out points.
 517 */
 518
 519 int mlt_playlist_append_io( mlt_playlist this, mlt_producer producer, mlt_position in, mlt_position out )
 520 {
 521         // Append to virtual list
 522         if ( in != -1 && out != -1 )
 523                 return mlt_playlist_virtual_append( this, producer, in, out );
 524         else
 525                 return mlt_playlist_append( this, producer );
 526 }
 527
 528 /** Append a blank to the playlist of a given length.
 529 */
 530
 531 int mlt_playlist_blank( mlt_playlist this, mlt_position length )
 532 {
 533         // Append to the virtual list
 534         return mlt_playlist_virtual_append( this, &this->blank, 0, length );
 535 }
 536
 537 /** Insert a producer into the playlist.
 538 */
 539
 540 int mlt_playlist_insert( mlt_playlist this, mlt_producer producer, int where, mlt_position in, mlt_position out )
 541 {
 542         // Append to end
 543         mlt_events_block( mlt_playlist_properties( this ), this );
 544         mlt_playlist_append_io( this, producer, in, out );
 545
 546         // Move to the position specified
 547         mlt_playlist_move( this, this->count - 1, where );
 548         mlt_events_unblock( mlt_playlist_properties( this ), this );
 549
 550         return mlt_playlist_virtual_refresh( this );
 551 }
 552
 553 /** Remove an entry in the playlist.
 554 */
 555
 556 int mlt_playlist_remove( mlt_playlist this, int where )
 557 {
 558         int error = where < 0 || where >= this->count;
 559         if ( error == 0 && mlt_playlist_unmix( this, where ) != 0 )
 560         {
 561                 // We need to know the current clip and the position within the playlist
 562                 int current = mlt_playlist_current_clip( this );
 563                 mlt_position position = mlt_producer_position( mlt_playlist_producer( this ) );
 564
 565                 // We need all the details about the clip we're removing
 566                 mlt_playlist_clip_info where_info;
 567                 playlist_entry *entry = this->list[ where ];
 568
 569                 // Loop variable
 570                 int i = 0;
 571
 572                 // Get the clip info
 573                 mlt_playlist_get_clip_info( this, &where_info, where );
 574
 575                 // Make sure the clip to be removed is valid and correct if necessary
 576                 if ( where < 0 )
 577                         where = 0;
 578                 if ( where >= this->count )
 579                         where = this->count - 1;
 580
 581                 // Close the producer associated to the clip info
 582                 mlt_event_close( entry->event );
 583                 mlt_producer_close( entry->producer );
 584                 if ( entry->mix_in != NULL )
 585                         entry->mix_in->mix_out = NULL;
 586                 if ( entry->mix_out != NULL )
 587                         entry->mix_out->mix_in = NULL;
 588
 589                 // Reorganise the list
 590                 for ( i = where + 1; i < this->count; i ++ )
 591                         this->list[ i - 1 ] = this->list[ i ];
 592                 this->count --;
 593
 594                 // Correct position
 595                 if ( where == current )
 596                         mlt_producer_seek( mlt_playlist_producer( this ), where_info.start );
 597                 else if ( where < current && this->count > 0 )
 598                         mlt_producer_seek( mlt_playlist_producer( this ), position - where_info.frame_count );
 599                 else if ( this->count == 0 )
 600                         mlt_producer_seek( mlt_playlist_producer( this ), 0 );
 601
 602                 // Free the entry
 603                 free( entry );
 604
 605                 // Refresh the playlist
 606                 mlt_playlist_virtual_refresh( this );
 607         }
 608
 609         return error;
 610 }
 611
 612 /** Move an entry in the playlist.
 613 */
 614
 615 int mlt_playlist_move( mlt_playlist this, int src, int dest )
 616 {
 617         int i;
 618
 619         /* We need to ensure that the requested indexes are valid and correct it as necessary */
 620         if ( src < 0 )
 621                 src = 0;
 622         if ( src >= this->count )
 623                 src = this->count - 1;
 624
 625         if ( dest < 0 )
 626                 dest = 0;
 627         if ( dest >= this->count )
 628                 dest = this->count - 1;
 629
 630         if ( src != dest && this->count > 1 )
 631         {
 632                 int current = mlt_playlist_current_clip( this );
 633                 mlt_position position = mlt_producer_position( mlt_playlist_producer( this ) );
 634                 playlist_entry *src_entry = NULL;
 635
 636                 // We need all the details about the current clip
 637                 mlt_playlist_clip_info current_info;
 638
 639                 mlt_playlist_get_clip_info( this, &current_info, current );
 640                 position -= current_info.start;
 641
 642                 if ( current == src )
 643                         current = dest;
 644                 else if ( current > src && current < dest )
 645                         current ++;
 646                 else if ( current == dest )
 647                         current = src;
 648
 649                 src_entry = this->list[ src ];
 650                 if ( src > dest )
 651                 {
 652                         for ( i = src; i > dest; i -- )
 653                                 this->list[ i ] = this->list[ i - 1 ];
 654                 }
 655                 else
 656                 {
 657                         for ( i = src; i < dest; i ++ )
 658                                 this->list[ i ] = this->list[ i + 1 ];
 659                 }
 660                 this->list[ dest ] = src_entry;
 661
 662                 mlt_playlist_get_clip_info( this, &current_info, current );
 663                 mlt_producer_seek( mlt_playlist_producer( this ), current_info.start + position );
 664                 mlt_playlist_virtual_refresh( this );
 665         }
 666
 667         return 0;
 668 }
 669
 670 /** Resize the current clip.
 671 */
 672
 673 int mlt_playlist_resize_clip( mlt_playlist this, int clip, mlt_position in, mlt_position out )
 674 {
 675         int error = clip < 0 || clip >= this->count;
 676         if ( error == 0 && mlt_playlist_resize_mix( this, clip, in, out ) != 0 )
 677         {
 678                 playlist_entry *entry = this->list[ clip ];
 679                 mlt_producer producer = entry->producer;
 680
 681                 if ( in <= -1 )
 682                         in = 0;
 683                 if ( out <= -1 || out >= mlt_producer_get_playtime( producer ) )
 684                         out = mlt_producer_get_playtime( producer ) - 1;
 685
 686                 if ( out < in )
 687                 {
 688                         mlt_position t = in;
 689                         in = out;
 690                         out = t;
 691                 }
 692
 693                 entry->frame_in = in;
 694                 entry->frame_out = out;
 695                 entry->frame_count = out - in + 1;
 696                 mlt_playlist_virtual_refresh( this );
 697         }
 698         return error;
 699 }
 700
 701 /** Split a clip on the playlist at the given position.
 702 */
 703
 704 int mlt_playlist_split( mlt_playlist this, int clip, mlt_position position )
 705 {
 706         int error = clip < 0 || clip >= this->count;
 707         if ( error == 0 )
 708         {
 709                 playlist_entry *entry = this->list[ clip ];
 710                 playlist_entry *new_entry = NULL;
 711                 if ( position > 0 && position < entry->frame_count )
 712                 {
 713                         int in = entry->frame_in;
 714                         int out = entry->frame_out;
 715                         mlt_events_block( mlt_playlist_properties( this ), this );
 716                         mlt_playlist_resize_clip( this, clip, in, in + position );
 717                         mlt_playlist_insert( this, entry->producer, clip + 1, in + position + 1, out );
 718                         new_entry = this->list[ clip + 1 ];
 719                         new_entry->mix_out = entry->mix_out;
 720                         new_entry->mix_out_length = entry->mix_out_length;
 721                         if ( entry->mix_out != NULL )
 722                                 entry->mix_out->mix_in = new_entry;
 723                         entry->mix_out = NULL;
 724                         entry->mix_out_length = 0;
 725                         mlt_events_unblock( mlt_playlist_properties( this ), this );
 726                         mlt_events_fire( mlt_playlist_properties( this ), "producer-changed", NULL );
 727                 }
 728                 else
 729                 {
 730                         error = 1;
 731                 }
 732         }
 733         return error;
 734 }
 735
 736 /** Join 1 or more consecutive clips.
 737 */
 738
 739 int mlt_playlist_join( mlt_playlist this, int clip, int count, int merge )
 740 {
 741         int error = clip < 0 || ( clip + 1 ) >= this->count;
 742         if ( error == 0 )
 743         {
 744                 int i = clip;
 745                 mlt_playlist new_clip = mlt_playlist_init( );
 746                 mlt_events_block( mlt_playlist_properties( this ), this );
 747                 if ( clip + count >= this->count )
 748                         count = this->count - clip;
 749                 for ( i = 0; i <= count; i ++ )
 750                 {
 751                         playlist_entry *entry = this->list[ clip ];
 752                         mlt_playlist_append_io( new_clip, entry->producer, entry->frame_in, entry->frame_out );
 753                         mlt_playlist_remove( this, clip );
 754                 }
 755                 mlt_events_unblock( mlt_playlist_properties( this ), this );
 756                 mlt_playlist_insert( this, mlt_playlist_producer( new_clip ), clip, 0, -1 );
 757                 mlt_playlist_close( new_clip );
 758         }
 759         return error;
 760 }
 761
 762 int mlt_playlist_mix( mlt_playlist this, int clip, int length, mlt_transition transition )
 763 {
 764         int error = ( clip < 0 || clip + 1 >= this->count ) && this->list[ clip ]->mix_out != NULL;
 765         if ( error == 0 )
 766         {
 767                 playlist_entry *mix = NULL;
 768                 playlist_entry *clip_a = this->list[ clip ];
 769                 playlist_entry *clip_b = this->list[ clip + 1 ];
 770                 mlt_tractor tractor = mlt_tractor_new( );
 771                 mlt_playlist track_a = mlt_playlist_init( );
 772                 mlt_playlist track_b = mlt_playlist_init( );
 773                 mlt_properties_set_int( mlt_tractor_properties( tractor ), "mlt_mix", 1 );
 774                 mlt_events_block( mlt_playlist_properties( this ), this );
 775                 mlt_playlist_resize_clip( this, clip, clip_a->frame_in, clip_a->frame_out - length );
 776                 mlt_playlist_resize_clip( this, clip + 1, clip_b->frame_in + length, clip_b->frame_out );
 777                 mlt_tractor_set_track( tractor, mlt_playlist_producer( track_a ), 0 );
 778                 mlt_tractor_set_track( tractor, mlt_playlist_producer( track_b ), 1 );
 779                 mlt_playlist_append_io( track_a, clip_a->producer, clip_a->frame_out + 1, clip_a->frame_out + length );
 780                 mlt_playlist_append_io( track_b, clip_b->producer, clip_b->frame_in - length, clip_b->frame_in - 1 );
 781                 mlt_playlist_insert( this, mlt_tractor_producer( tractor ), clip + 1, -1, -1 );
 782
 783                 // Store mix info so that we can manipulate clips on either side
 784                 mix = this->list[ clip + 1 ];
 785                 mix->mix_in = clip_a;
 786                 mix->mix_out = clip_b;
 787                 mix->mix_out_length = length;
 788                 mix->mix_in_length = length;
 789                 clip_a->mix_out = mix;
 790                 clip_a->mix_out_length = length;
 791                 clip_b->mix_in = mix;
 792                 clip_b->mix_in_length = length;
 793
 794                 if ( transition != NULL )
 795                 {
 796                         mlt_field field = mlt_tractor_field( tractor );
 797                         mlt_field_plant_transition( field, transition, 0, 1 );
 798                         mlt_transition_set_in_and_out( transition, 0, length - 1 );
 799                 }
 800                 mlt_events_unblock( mlt_playlist_properties( this ), this );
 801                 mlt_events_fire( mlt_playlist_properties( this ), "producer-changed", NULL );
 802                 mlt_playlist_close( track_a );
 803                 mlt_playlist_close( track_b );
 804                 mlt_tractor_close( tractor );
 805         }
 806         return error;
 807 }
 808
 809 static int mlt_playlist_unmix( mlt_playlist this, int clip )
 810 {
 811         int error = ( clip < 0 || clip >= this->count );
 812
 813         // Ensure that the clip request is actually a mix
 814         if ( error == 0 )
 815         {
 816                 mlt_producer producer = this->list[ clip ]->producer;
 817                 mlt_properties properties = mlt_producer_properties( producer );
 818                 error = !mlt_properties_get_int( properties, "mlt_mix" );
 819         }
 820
 821         if ( error == 0 )
 822         {
 823                 playlist_entry *mix = this->list[ clip ];
 824                 playlist_entry *clip_a = mix->mix_in;
 825                 playlist_entry *clip_b = mix->mix_out;
 826                 int length = mix->mix_in_length;
 827                 mlt_events_block( mlt_playlist_properties( this ), this );
 828
 829                 if ( clip_a != NULL )
 830                 {
 831                         clip_a->frame_out += length;
 832                         clip_a->frame_count += length;
 833                         clip_a->mix_out = NULL;
 834                         clip_a->mix_out_length = 0;
 835                 }
 836
 837                 if ( clip_b != NULL )
 838                 {
 839                         clip_b->frame_in -= length;
 840                         clip_b->frame_count += length;
 841                         clip_b->mix_in = NULL;
 842                         clip_b->mix_in_length = 0;
 843                 }
 844
 845                 mlt_properties_set_int( mlt_producer_properties( mix->producer ), "mlt_mix", 0 );
 846                 mlt_playlist_remove( this, clip );
 847                 mlt_events_unblock( mlt_playlist_properties( this ), this );
 848                 mlt_events_fire( mlt_playlist_properties( this ), "producer-changed", NULL );
 849         }
 850         return error;
 851 }
 852
 853 static int mlt_playlist_resize_mix( mlt_playlist this, int clip, int in, int out )
 854 {
 855         int error = ( clip < 0 || clip >= this->count );
 856
 857         // Ensure that the clip request is actually a mix
 858         if ( error == 0 )
 859         {
 860                 mlt_producer producer = this->list[ clip ]->producer;
 861                 mlt_properties properties = mlt_producer_properties( producer );
 862                 error = !mlt_properties_get_int( properties, "mlt_mix" );
 863         }
 864
 865         if ( error == 0 )
 866         {
 867                 playlist_entry *mix = this->list[ clip ];
 868                 playlist_entry *clip_a = mix->mix_in;
 869                 playlist_entry *clip_b = mix->mix_out;
 870                 int length = out - in + 1;
 871                 int length_diff = length - mix->mix_in_length;
 872                 mlt_events_block( mlt_playlist_properties( this ), this );
 873
 874                 if ( clip_a != NULL )
 875                 {
 876                         clip_a->frame_out -= length_diff;
 877                         clip_a->frame_count -= length_diff;
 878                         clip_a->mix_out_length -= length_diff;
 879                 }
 880
 881                 if ( clip_b != NULL )
 882                 {
 883                         clip_b->frame_in += length_diff;
 884                         clip_b->frame_count -= length_diff;
 885                         clip_b->mix_in_length -= length_diff;
 886                 }
 887
 888                 mix->frame_in = 0;
 889                 mix->frame_out = length - 1;
 890                 mix->frame_count = length;
 891                 mix->mix_in_length = length;
 892                 mix->mix_out_length = length;
 893
 894                 mlt_events_unblock( mlt_playlist_properties( this ), this );
 895                 mlt_events_fire( mlt_playlist_properties( this ), "producer-changed", NULL );
 896         }
 897         return error;
 898 }
 899
 900 /** Get the current frame.
 901 */
 902
 903 static int producer_get_frame( mlt_producer producer, mlt_frame_ptr frame, int index )
 904 {
 905         // Get this mlt_playlist
 906         mlt_playlist this = producer->child;
 907
 908         // Get the real producer
 909         mlt_service real = mlt_playlist_virtual_seek( this );
 910
 911         // Get the frame
 912         mlt_service_get_frame( real, frame, index );
 913
 914         // Check if we're at the end of the clip
 915         mlt_properties properties = mlt_frame_properties( *frame );
 916         if ( mlt_properties_get_int( properties, "end_of_clip" ) )
 917                 mlt_playlist_virtual_set_out( this );
 918
 919         // Check for notifier and call with appropriate argument
 920         mlt_properties playlist_properties = mlt_producer_properties( producer );
 921         void ( *notifier )( void * ) = mlt_properties_get_data( playlist_properties, "notifier", NULL );
 922         if ( notifier != NULL )
 923         {
 924                 void *argument = mlt_properties_get_data( playlist_properties, "notifier_arg", NULL );
 925                 notifier( argument );
 926         }
 927
 928         // Update position on the frame we're creating
 929         mlt_frame_set_position( *frame, mlt_producer_frame( producer ) );
 930
 931         // Position ourselves on the next frame
 932         mlt_producer_prepare_next( producer );
 933
 934         return 0;
 935 }
 936
 937 /** Close the playlist.
 938 */
 939
 940 void mlt_playlist_close( mlt_playlist this )
 941 {
 942         if ( this != NULL && mlt_properties_dec_ref( mlt_playlist_properties( this ) ) <= 0 )
 943         {
 944                 int i = 0;
 945                 this->parent.close = NULL;
 946                 for ( i = 0; i < this->count; i ++ )
 947                 {
 948                         mlt_event_close( this->list[ i ]->event );
 949                         mlt_producer_close( this->list[ i ]->producer );
 950                         free( this->list[ i ] );
 951                 }
 952                 mlt_producer_close( &this->blank );
 953                 mlt_producer_close( &this->parent );
 954                 free( this->list );
 955                 free( this );
 956         }
 957 }