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 ]->frame_in != mlt_producer_get_in( producer ) ||
 174                          this->list[ i ]->frame_out != mlt_producer_get_out( producer ) );
 175                 {
 176                         // This clip should be removed...
 177                         if ( current_length == 1 )
 178                         {
 179                                 this->list[ i ]->frame_in = 0;
 180                                 this->list[ i ]->frame_out = 0;
 181                                 this->list[ i ]->frame_count = 0;
 182                         }
 183                         else
 184                         {
 185                                 this->list[ i ]->frame_in = mlt_producer_get_in( producer );
 186                                 this->list[ i ]->frame_out = mlt_producer_get_out( producer );
 187                                 this->list[ i ]->frame_count = current_length;
 188                         }
 189
 190                         // Update the producer_length
 191                         this->list[ i ]->producer_length = current_length;
 192                 }
 193
 194                 // Update the frame_count for this clip
 195                 frame_count += this->list[ i ]->frame_count;
 196         }
 197
 198         // Refresh all properties
 199         mlt_properties_set_double( properties, "first_fps", fps );
 200         mlt_properties_set_double( properties, "fps", fps == 0 ? 25 : fps );
 201         mlt_events_block( properties, properties );
 202         mlt_properties_set_position( properties, "length", frame_count );
 203         mlt_events_unblock( properties, properties );
 204         mlt_properties_set_position( properties, "out", frame_count - 1 );
 205
 206         return 0;
 207 }
 208
 209 /** Listener for producers on the playlist.
 210 */
 211
 212 static void mlt_playlist_listener( mlt_producer producer, mlt_playlist this )
 213 {
 214         mlt_playlist_virtual_refresh( this );
 215 }
 216
 217 /** Append to the virtual playlist.
 218 */
 219
 220 static int mlt_playlist_virtual_append( mlt_playlist this, mlt_producer source, mlt_position in, mlt_position out )
 221 {
 222         mlt_producer producer = mlt_producer_is_cut( source ) ? source : mlt_producer_cut( source, in, out );
 223         mlt_properties properties = mlt_producer_properties( producer );
 224
 225         // If we have a cut, then use the in/out points from the cut
 226         if ( mlt_producer_is_cut( source ) )
 227         {
 228                 mlt_properties_inc_ref( properties );
 229                 in = mlt_producer_get_in( source );
 230                 out = mlt_producer_get_out( source );
 231         }
 232
 233         // Check that we have room
 234         if ( this->count >= this->size )
 235         {
 236                 int i;
 237                 this->list = realloc( this->list, ( this->size + 10 ) * sizeof( playlist_entry * ) );
 238                 for ( i = this->size; i < this->size + 10; i ++ ) this->list[ i ] = NULL;
 239                 this->size += 10;
 240         }
 241
 242         this->list[ this->count ] = calloc( sizeof( playlist_entry ), 1 );
 243         this->list[ this->count ]->producer = producer;
 244         this->list[ this->count ]->frame_in = in;
 245         this->list[ this->count ]->frame_out = out;
 246         this->list[ this->count ]->frame_count = out - in + 1;
 247         this->list[ this->count ]->producer_length = mlt_producer_get_out( producer ) - mlt_producer_get_in( producer ) + 1;
 248         this->list[ this->count ]->event = mlt_events_listen( properties, this, "producer-changed", ( mlt_listener )mlt_playlist_listener );
 249         mlt_event_inc_ref( this->list[ this->count ]->event );
 250
 251         mlt_properties_set( properties, "eof", "pause" );
 252
 253         mlt_producer_set_speed( producer, 0 );
 254
 255         this->count ++;
 256
 257
 258         return mlt_playlist_virtual_refresh( this );
 259 }
 260
 261 /** Seek in the virtual playlist.
 262 */
 263
 264 static mlt_service mlt_playlist_virtual_seek( mlt_playlist this )
 265 {
 266         // Default producer to blank
 267         mlt_producer producer = NULL;
 268
 269         // Map playlist position to real producer in virtual playlist
 270         mlt_position position = mlt_producer_frame( &this->parent );
 271
 272         mlt_position original = position;
 273
 274         // Total number of frames
 275         int64_t total = 0;
 276
 277         // Get the properties
 278         mlt_properties properties = mlt_playlist_properties( this );
 279
 280         // Get the eof handling
 281         char *eof = mlt_properties_get( properties, "eof" );
 282
 283         // Index for the main loop
 284         int i = 0;
 285
 286         // Loop for each producer until found
 287         for ( i = 0; i < this->count; i ++ )
 288         {
 289                 // Increment the total
 290                 total += this->list[ i ]->frame_count;
 291
 292                 // Check if the position indicates that we have found the clip
 293                 if ( position < this->list[ i ]->frame_count )
 294                 {
 295                         // Found it, now break
 296                         producer = this->list[ i ]->producer;
 297                         break;
 298                 }
 299                 else
 300                 {
 301                         // Decrement position by length of this entry
 302                         position -= this->list[ i ]->frame_count;
 303                 }
 304         }
 305
 306         // Seek in real producer to relative position
 307         if ( producer != NULL )
 308         {
 309                 mlt_producer_seek( producer, position );
 310         }
 311         else if ( !strcmp( eof, "pause" ) && total > 0 )
 312         {
 313                 playlist_entry *entry = this->list[ this->count - 1 ];
 314                 mlt_producer this_producer = mlt_playlist_producer( this );
 315                 mlt_producer_seek( this_producer, original - 1 );
 316                 producer = entry->producer;
 317                 mlt_producer_seek( producer, entry->frame_out );
 318                 mlt_producer_set_speed( this_producer, 0 );
 319                 mlt_producer_set_speed( producer, 0 );
 320         }
 321         else if ( !strcmp( eof, "loop" ) && total > 0 )
 322         {
 323                 playlist_entry *entry = this->list[ 0 ];
 324                 mlt_producer this_producer = mlt_playlist_producer( this );
 325                 mlt_producer_seek( this_producer, 0 );
 326                 producer = entry->producer;
 327                 mlt_producer_seek( producer, 0 );
 328         }
 329         else
 330         {
 331                 producer = &this->blank;
 332         }
 333
 334         return mlt_producer_service( producer );
 335 }
 336
 337 /** Invoked when a producer indicates that it has prematurely reached its end.
 338 */
 339
 340 static mlt_producer mlt_playlist_virtual_set_out( mlt_playlist this )
 341 {
 342         // Default producer to blank
 343         mlt_producer producer = &this->blank;
 344
 345         // Map playlist position to real producer in virtual playlist
 346         mlt_position position = mlt_producer_frame( &this->parent );
 347
 348         // Loop through the virtual playlist
 349         int i = 0;
 350
 351         for ( i = 0; i < this->count; i ++ )
 352         {
 353                 if ( position < this->list[ i ]->frame_count )
 354                 {
 355                         // Found it, now break
 356                         producer = this->list[ i ]->producer;
 357                         break;
 358                 }
 359                 else
 360                 {
 361                         // Decrement position by length of this entry
 362                         position -= this->list[ i ]->frame_count;
 363                 }
 364         }
 365
 366         // Seek in real producer to relative position
 367         if ( i < this->count && this->list[ i ]->frame_out != position )
 368         {
 369                 // Update the frame_count for the changed clip (hmmm)
 370                 this->list[ i ]->frame_out = position;
 371                 this->list[ i ]->frame_count = this->list[ i ]->frame_out - this->list[ i ]->frame_in + 1;
 372
 373                 // Refresh the playlist
 374                 mlt_playlist_virtual_refresh( this );
 375         }
 376
 377         return producer;
 378 }
 379
 380 /** Obtain the current clips index.
 381 */
 382
 383 int mlt_playlist_current_clip( mlt_playlist this )
 384 {
 385         // Map playlist position to real producer in virtual playlist
 386         mlt_position position = mlt_producer_frame( &this->parent );
 387
 388         // Loop through the virtual playlist
 389         int i = 0;
 390
 391         for ( i = 0; i < this->count; i ++ )
 392         {
 393                 if ( position < this->list[ i ]->frame_count )
 394                 {
 395                         // Found it, now break
 396                         break;
 397                 }
 398                 else
 399                 {
 400                         // Decrement position by length of this entry
 401                         position -= this->list[ i ]->frame_count;
 402                 }
 403         }
 404
 405         return i;
 406 }
 407
 408 /** Obtain the current clips producer.
 409 */
 410
 411 mlt_producer mlt_playlist_current( mlt_playlist this )
 412 {
 413         int i = mlt_playlist_current_clip( this );
 414         if ( i < this->count )
 415                 return this->list[ i ]->producer;
 416         else
 417                 return &this->blank;
 418 }
 419
 420 /** Get the position which corresponds to the start of the next clip.
 421 */
 422
 423 mlt_position mlt_playlist_clip( mlt_playlist this, mlt_whence whence, int index )
 424 {
 425         mlt_position position = 0;
 426         int absolute_clip = index;
 427         int i = 0;
 428
 429         // Determine the absolute clip
 430         switch ( whence )
 431         {
 432                 case mlt_whence_relative_start:
 433                         absolute_clip = index;
 434                         break;
 435
 436                 case mlt_whence_relative_current:
 437                         absolute_clip = mlt_playlist_current_clip( this ) + index;
 438                         break;
 439
 440                 case mlt_whence_relative_end:
 441                         absolute_clip = this->count - index;
 442                         break;
 443         }
 444
 445         // Check that we're in a valid range
 446         if ( absolute_clip < 0 )
 447                 absolute_clip = 0;
 448         else if ( absolute_clip > this->count )
 449                 absolute_clip = this->count;
 450
 451         // Now determine the position
 452         for ( i = 0; i < absolute_clip; i ++ )
 453                 position += this->list[ i ]->frame_count;
 454
 455         return position;
 456 }
 457
 458 /** Get all the info about the clip specified.
 459 */
 460
 461 int mlt_playlist_get_clip_info( mlt_playlist this, mlt_playlist_clip_info *info, int index )
 462 {
 463         int error = index < 0 || index >= this->count;
 464         memset( info, 0, sizeof( mlt_playlist_clip_info ) );
 465         if ( !error )
 466         {
 467                 mlt_producer producer = mlt_producer_cut_parent( this->list[ index ]->producer );
 468                 mlt_properties properties = mlt_producer_properties( producer );
 469                 info->clip = index;
 470                 info->producer = producer;
 471                 info->start = mlt_playlist_clip( this, mlt_whence_relative_start, index );
 472                 info->resource = mlt_properties_get( properties, "resource" );
 473                 info->frame_in = this->list[ index ]->frame_in;
 474                 info->frame_out = this->list[ index ]->frame_out;
 475                 info->frame_count = this->list[ index ]->frame_count;
 476                 info->length = mlt_producer_get_length( producer );
 477                 info->fps = mlt_producer_get_fps( producer );
 478                 info->event = this->list[ index ]->event;
 479         }
 480
 481         // Determine the consuming filter service
 482         if ( info->producer != NULL )
 483         {
 484                 info->service = mlt_producer_service( info->producer );
 485                 while ( mlt_service_consumer( info->service ) != NULL )
 486                         info->service = mlt_service_consumer( info->service );
 487         }
 488
 489         return error;
 490 }
 491
 492 /** Get number of clips in the playlist.
 493 */
 494
 495 int mlt_playlist_count( mlt_playlist this )
 496 {
 497         return this->count;
 498 }
 499
 500 /** Clear the playlist.
 501 */
 502
 503 int mlt_playlist_clear( mlt_playlist this )
 504 {
 505         int i;
 506         for ( i = 0; i < this->count; i ++ )
 507         {
 508                 mlt_event_close( this->list[ i ]->event );
 509                 mlt_producer_close( this->list[ i ]->producer );
 510         }
 511         this->count = 0;
 512         mlt_properties_set_double( mlt_playlist_properties( this ), "first_fps", 0 );
 513         return mlt_playlist_virtual_refresh( this );
 514 }
 515
 516 /** Append a producer to the playlist.
 517 */
 518
 519 int mlt_playlist_append( mlt_playlist this, mlt_producer producer )
 520 {
 521         // Append to virtual list
 522         return mlt_playlist_virtual_append( this, producer, 0, mlt_producer_get_playtime( producer ) - 1 );
 523 }
 524
 525 /** Append a producer to the playlist with in/out points.
 526 */
 527
 528 int mlt_playlist_append_io( mlt_playlist this, mlt_producer producer, mlt_position in, mlt_position out )
 529 {
 530         // Append to virtual list
 531         if ( in != -1 && out != -1 )
 532                 return mlt_playlist_virtual_append( this, producer, in, out );
 533         else
 534                 return mlt_playlist_append( this, producer );
 535 }
 536
 537 /** Append a blank to the playlist of a given length.
 538 */
 539
 540 int mlt_playlist_blank( mlt_playlist this, mlt_position length )
 541 {
 542         // Append to the virtual list
 543         return mlt_playlist_virtual_append( this, &this->blank, 0, length );
 544 }
 545
 546 /** Insert a producer into the playlist.
 547 */
 548
 549 int mlt_playlist_insert( mlt_playlist this, mlt_producer producer, int where, mlt_position in, mlt_position out )
 550 {
 551         // Append to end
 552         mlt_events_block( mlt_playlist_properties( this ), this );
 553         mlt_playlist_append_io( this, producer, in, out );
 554
 555         // Move to the position specified
 556         mlt_playlist_move( this, this->count - 1, where );
 557         mlt_events_unblock( mlt_playlist_properties( this ), this );
 558
 559         return mlt_playlist_virtual_refresh( this );
 560 }
 561
 562 /** Remove an entry in the playlist.
 563 */
 564
 565 int mlt_playlist_remove( mlt_playlist this, int where )
 566 {
 567         int error = where < 0 || where >= this->count;
 568         if ( error == 0 && mlt_playlist_unmix( this, where ) != 0 )
 569         {
 570                 // We need to know the current clip and the position within the playlist
 571                 int current = mlt_playlist_current_clip( this );
 572                 mlt_position position = mlt_producer_position( mlt_playlist_producer( this ) );
 573
 574                 // We need all the details about the clip we're removing
 575                 mlt_playlist_clip_info where_info;
 576                 playlist_entry *entry = this->list[ where ];
 577
 578                 // Loop variable
 579                 int i = 0;
 580
 581                 // Get the clip info
 582                 mlt_playlist_get_clip_info( this, &where_info, where );
 583
 584                 // Make sure the clip to be removed is valid and correct if necessary
 585                 if ( where < 0 )
 586                         where = 0;
 587                 if ( where >= this->count )
 588                         where = this->count - 1;
 589
 590                 // Close the producer associated to the clip info
 591                 mlt_event_close( entry->event );
 592                 mlt_producer_close( entry->producer );
 593                 if ( entry->mix_in != NULL )
 594                         entry->mix_in->mix_out = NULL;
 595                 if ( entry->mix_out != NULL )
 596                         entry->mix_out->mix_in = NULL;
 597
 598                 // Reorganise the list
 599                 for ( i = where + 1; i < this->count; i ++ )
 600                         this->list[ i - 1 ] = this->list[ i ];
 601                 this->count --;
 602
 603                 // Correct position
 604                 if ( where == current )
 605                         mlt_producer_seek( mlt_playlist_producer( this ), where_info.start );
 606                 else if ( where < current && this->count > 0 )
 607                         mlt_producer_seek( mlt_playlist_producer( this ), position - where_info.frame_count );
 608                 else if ( this->count == 0 )
 609                         mlt_producer_seek( mlt_playlist_producer( this ), 0 );
 610
 611                 // Free the entry
 612                 free( entry );
 613
 614                 // Refresh the playlist
 615                 mlt_playlist_virtual_refresh( this );
 616         }
 617
 618         return error;
 619 }
 620
 621 /** Move an entry in the playlist.
 622 */
 623
 624 int mlt_playlist_move( mlt_playlist this, int src, int dest )
 625 {
 626         int i;
 627
 628         /* We need to ensure that the requested indexes are valid and correct it as necessary */
 629         if ( src < 0 )
 630                 src = 0;
 631         if ( src >= this->count )
 632                 src = this->count - 1;
 633
 634         if ( dest < 0 )
 635                 dest = 0;
 636         if ( dest >= this->count )
 637                 dest = this->count - 1;
 638
 639         if ( src != dest && this->count > 1 )
 640         {
 641                 int current = mlt_playlist_current_clip( this );
 642                 mlt_position position = mlt_producer_position( mlt_playlist_producer( this ) );
 643                 playlist_entry *src_entry = NULL;
 644
 645                 // We need all the details about the current clip
 646                 mlt_playlist_clip_info current_info;
 647
 648                 mlt_playlist_get_clip_info( this, &current_info, current );
 649                 position -= current_info.start;
 650
 651                 if ( current == src )
 652                         current = dest;
 653                 else if ( current > src && current < dest )
 654                         current ++;
 655                 else if ( current == dest )
 656                         current = src;
 657
 658                 src_entry = this->list[ src ];
 659                 if ( src > dest )
 660                 {
 661                         for ( i = src; i > dest; i -- )
 662                                 this->list[ i ] = this->list[ i - 1 ];
 663                 }
 664                 else
 665                 {
 666                         for ( i = src; i < dest; i ++ )
 667                                 this->list[ i ] = this->list[ i + 1 ];
 668                 }
 669                 this->list[ dest ] = src_entry;
 670
 671                 mlt_playlist_get_clip_info( this, &current_info, current );
 672                 mlt_producer_seek( mlt_playlist_producer( this ), current_info.start + position );
 673                 mlt_playlist_virtual_refresh( this );
 674         }
 675
 676         return 0;
 677 }
 678
 679 /** Resize the current clip.
 680 */
 681
 682 int mlt_playlist_resize_clip( mlt_playlist this, int clip, mlt_position in, mlt_position out )
 683 {
 684         int error = clip < 0 || clip >= this->count;
 685         if ( error == 0 && mlt_playlist_resize_mix( this, clip, in, out ) != 0 )
 686         {
 687                 playlist_entry *entry = this->list[ clip ];
 688                 mlt_producer producer = entry->producer;
 689
 690                 if ( in <= -1 )
 691                         in = 0;
 692                 if ( out <= -1 || out >= mlt_producer_get_length( producer ) )
 693                         out = mlt_producer_get_length( producer ) - 1;
 694
 695                 if ( out < in )
 696                 {
 697                         mlt_position t = in;
 698                         in = out;
 699                         out = t;
 700                 }
 701
 702                 mlt_producer_set_in_and_out( producer, in, out );
 703         }
 704         return error;
 705 }
 706
 707 /** Split a clip on the playlist at the given position.
 708 */
 709
 710 int mlt_playlist_split( mlt_playlist this, int clip, mlt_position position )
 711 {
 712         int error = clip < 0 || clip >= this->count;
 713         if ( error == 0 )
 714         {
 715                 playlist_entry *entry = this->list[ clip ];
 716                 if ( position > 0 && position < entry->frame_count )
 717                 {
 718                         mlt_producer parent = mlt_producer_cut_parent( entry->producer );
 719                         mlt_producer split = NULL;
 720                         int in = entry->frame_in;
 721                         int out = entry->frame_out;
 722                         mlt_events_block( mlt_playlist_properties( this ), this );
 723                         mlt_playlist_resize_clip( this, clip, in, in + position );
 724                         split = mlt_producer_cut( parent, in + position + 1, out );
 725                         mlt_playlist_insert( this, split, clip + 1, -1, -1 );
 726                         mlt_events_unblock( mlt_playlist_properties( this ), this );
 727                         mlt_events_fire( mlt_playlist_properties( this ), "producer-changed", NULL );
 728                 }
 729                 else
 730                 {
 731                         error = 1;
 732                 }
 733         }
 734         return error;
 735 }
 736
 737 /** Join 1 or more consecutive clips.
 738 */
 739
 740 int mlt_playlist_join( mlt_playlist this, int clip, int count, int merge )
 741 {
 742         int error = clip < 0 || ( clip + 1 ) >= this->count;
 743         if ( error == 0 )
 744         {
 745                 int i = clip;
 746                 mlt_playlist new_clip = mlt_playlist_init( );
 747                 mlt_events_block( mlt_playlist_properties( this ), this );
 748                 if ( clip + count >= this->count )
 749                         count = this->count - clip;
 750                 for ( i = 0; i <= count; i ++ )
 751                 {
 752                         playlist_entry *entry = this->list[ clip ];
 753                         mlt_playlist_append( new_clip, entry->producer );
 754                         mlt_playlist_remove( this, clip );
 755                 }
 756                 mlt_events_unblock( mlt_playlist_properties( this ), this );
 757                 mlt_playlist_insert( this, mlt_playlist_producer( new_clip ), clip, 0, -1 );
 758                 mlt_playlist_close( new_clip );
 759         }
 760         return error;
 761 }
 762
 763 int mlt_playlist_mix( mlt_playlist this, int clip, int length, mlt_transition transition )
 764 {
 765         int error = ( clip < 0 || clip + 1 >= this->count ) && this->list[ clip ]->mix_out != NULL;
 766         if ( error == 0 )
 767         {
 768                 playlist_entry *clip_a = this->list[ clip ];
 769                 playlist_entry *clip_b = this->list[ clip + 1 ];
 770                 mlt_producer track_a;
 771                 mlt_producer track_b;
 772                 mlt_tractor tractor = mlt_tractor_new( );
 773                 mlt_events_block( mlt_playlist_properties( this ), this );
 774
 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
 778                 track_a = mlt_producer_cut( mlt_producer_cut_parent( clip_a->producer ), clip_a->frame_out + 1, clip_a->frame_out + length );
 779                 track_b = mlt_producer_cut( mlt_producer_cut_parent( clip_b->producer ), clip_b->frame_in - length, clip_b->frame_in - 1 );
 780                 mlt_tractor_set_track( tractor, track_a, 0 );
 781                 mlt_tractor_set_track( tractor, track_b, 1 );
 782                 mlt_playlist_insert( this, mlt_tractor_producer( tractor ), clip + 1, -1, -1 );
 783                 mlt_properties_set_data( mlt_tractor_properties( tractor ), "mlt_mix", tractor, 0, NULL, NULL );
 784
 785                 if ( transition != NULL )
 786                 {
 787                         mlt_field field = mlt_tractor_field( tractor );
 788                         mlt_field_plant_transition( field, transition, 0, 1 );
 789                         mlt_transition_set_in_and_out( transition, 0, length - 1 );
 790                 }
 791
 792                 if ( clip_b->frame_count <= 0 )
 793                         mlt_playlist_remove( this, clip + 2 );
 794
 795                 if ( clip_a->frame_count <= 0 )
 796                         mlt_playlist_remove( this, clip );
 797
 798                 mlt_events_unblock( mlt_playlist_properties( this ), this );
 799                 mlt_events_fire( mlt_playlist_properties( this ), "producer-changed", NULL );
 800                 mlt_producer_close( track_a );
 801                 mlt_producer_close( track_b );
 802                 mlt_tractor_close( tractor );
 803         }
 804         return error;
 805 }
 806
 807 static int mlt_playlist_unmix( mlt_playlist this, int clip )
 808 {
 809         int error = ( clip < 0 || clip >= this->count );
 810
 811         // Ensure that the clip request is actually a mix
 812         if ( error == 0 )
 813         {
 814                 mlt_producer producer = this->list[ clip ]->producer;
 815                 mlt_properties properties = mlt_producer_properties( producer );
 816                 error = !mlt_properties_get_int( properties, "mlt_mix" );
 817         }
 818
 819         if ( error == 0 )
 820         {
 821                 playlist_entry *mix = this->list[ clip ];
 822                 playlist_entry *clip_a = mix->mix_in;
 823                 playlist_entry *clip_b = mix->mix_out;
 824                 int length = mix->mix_in_length;
 825                 mlt_events_block( mlt_playlist_properties( this ), this );
 826
 827                 if ( clip_a != NULL )
 828                 {
 829                         clip_a->frame_out += length;
 830                         clip_a->frame_count += length;
 831                         clip_a->mix_out = NULL;
 832                         clip_a->mix_out_length = 0;
 833                 }
 834                 else
 835                 {
 836                         mlt_tractor tractor = ( mlt_tractor )mix->producer;
 837                         mlt_playlist playlist = ( mlt_playlist )mlt_tractor_get_track( tractor, 0 );
 838                         mlt_producer producer = playlist->list[ 0 ]->producer;
 839                         mlt_playlist_insert( this, producer, clip, playlist->list[0]->frame_in, playlist->list[0]->frame_out );
 840                         clip ++;
 841                 }
 842
 843                 if ( clip_b != NULL )
 844                 {
 845                         clip_b->frame_in -= length;
 846                         clip_b->frame_count += length;
 847                         clip_b->mix_in = NULL;
 848                         clip_b->mix_in_length = 0;
 849                 }
 850                 else
 851                 {
 852                         mlt_tractor tractor = ( mlt_tractor )mix->producer;
 853                         mlt_playlist playlist = ( mlt_playlist )mlt_tractor_get_track( tractor, 1 );
 854                         mlt_producer producer = playlist->list[ 0 ]->producer;
 855                         mlt_playlist_insert( this, producer, clip + 1, playlist->list[0]->frame_in, playlist->list[0]->frame_out );
 856                 }
 857
 858                 mlt_properties_set_int( mlt_producer_properties( mix->producer ), "mlt_mix", 0 );
 859                 mlt_playlist_remove( this, clip );
 860                 mlt_events_unblock( mlt_playlist_properties( this ), this );
 861                 mlt_events_fire( mlt_playlist_properties( this ), "producer-changed", NULL );
 862         }
 863         return error;
 864 }
 865
 866 static int mlt_playlist_resize_mix( mlt_playlist this, int clip, int in, int out )
 867 {
 868         int error = ( clip < 0 || clip >= this->count );
 869
 870         // Ensure that the clip request is actually a mix
 871         if ( error == 0 )
 872         {
 873                 mlt_producer producer = this->list[ clip ]->producer;
 874                 mlt_properties properties = mlt_producer_properties( producer );
 875                 error = !mlt_properties_get_int( properties, "mlt_mix" );
 876         }
 877
 878         if ( error == 0 )
 879         {
 880                 playlist_entry *mix = this->list[ clip ];
 881                 playlist_entry *clip_a = mix->mix_in;
 882                 playlist_entry *clip_b = mix->mix_out;
 883                 int length = out - in + 1;
 884                 int length_diff = length - mix->mix_in_length;
 885                 mlt_events_block( mlt_playlist_properties( this ), this );
 886
 887                 if ( clip_a != NULL )
 888                 {
 889                         clip_a->frame_out -= length_diff;
 890                         clip_a->frame_count -= length_diff;
 891                         clip_a->mix_out_length -= length_diff;
 892                 }
 893
 894                 if ( clip_b != NULL )
 895                 {
 896                         clip_b->frame_in += length_diff;
 897                         clip_b->frame_count -= length_diff;
 898                         clip_b->mix_in_length -= length_diff;
 899                 }
 900
 901                 mix->frame_in = 0;
 902                 mix->frame_out = length - 1;
 903                 mix->frame_count = length;
 904                 mix->mix_in_length = length;
 905                 mix->mix_out_length = length;
 906
 907                 mlt_events_unblock( mlt_playlist_properties( this ), this );
 908                 mlt_events_fire( mlt_playlist_properties( this ), "producer-changed", NULL );
 909         }
 910         return error;
 911 }
 912
 913 /** Get the current frame.
 914 */
 915
 916 static int producer_get_frame( mlt_producer producer, mlt_frame_ptr frame, int index )
 917 {
 918         // Get this mlt_playlist
 919         mlt_playlist this = producer->child;
 920
 921         // Get the real producer
 922         mlt_service real = mlt_playlist_virtual_seek( this );
 923
 924         // Get the frame
 925         mlt_service_get_frame( real, frame, index );
 926
 927         // Check if we're at the end of the clip
 928         mlt_properties properties = mlt_frame_properties( *frame );
 929         if ( mlt_properties_get_int( properties, "end_of_clip" ) )
 930                 mlt_playlist_virtual_set_out( this );
 931
 932         // Check for notifier and call with appropriate argument
 933         mlt_properties playlist_properties = mlt_producer_properties( producer );
 934         void ( *notifier )( void * ) = mlt_properties_get_data( playlist_properties, "notifier", NULL );
 935         if ( notifier != NULL )
 936         {
 937                 void *argument = mlt_properties_get_data( playlist_properties, "notifier_arg", NULL );
 938                 notifier( argument );
 939         }
 940
 941         // Update position on the frame we're creating
 942         mlt_frame_set_position( *frame, mlt_producer_frame( producer ) );
 943
 944         // Position ourselves on the next frame
 945         mlt_producer_prepare_next( producer );
 946
 947         return 0;
 948 }
 949
 950 /** Close the playlist.
 951 */
 952
 953 void mlt_playlist_close( mlt_playlist this )
 954 {
 955         if ( this != NULL && mlt_properties_dec_ref( mlt_playlist_properties( this ) ) <= 0 )
 956         {
 957                 int i = 0;
 958                 this->parent.close = NULL;
 959                 for ( i = 0; i < this->count; i ++ )
 960                 {
 961                         mlt_event_close( this->list[ i ]->event );
 962                         mlt_producer_close( this->list[ i ]->producer );
 963                         free( this->list[ i ] );
 964                 }
 965                 mlt_producer_close( &this->blank );
 966                 mlt_producer_close( &this->parent );
 967                 free( this->list );
 968                 free( this );
 969         }
 970 }