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[mlt] / 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_multitrack.h"
26 #include "mlt_field.h"
27 #include "mlt_frame.h"
28 #include "mlt_transition.h"
29
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33
34 /** Virtual playlist entry.
35 */
36
37 struct playlist_entry_s
38 {
39         mlt_producer producer;
40         mlt_position frame_in;
41         mlt_position frame_out;
42         mlt_position frame_count;
43         int repeat;
44         mlt_position producer_length;
45         mlt_event event;
46         int preservation_hack;
47 };
48
49 /** Forward declarations
50 */
51
52 static int producer_get_frame( mlt_producer producer, mlt_frame_ptr frame, int index );
53 static int mlt_playlist_unmix( mlt_playlist this, int clip );
54 static int mlt_playlist_resize_mix( mlt_playlist this, int clip, int in, int out );
55
56 /** Constructor.
57 */
58
59 mlt_playlist mlt_playlist_init( )
60 {
61         mlt_playlist this = calloc( sizeof( struct mlt_playlist_s ), 1 );
62         if ( this != NULL )
63         {
64                 mlt_producer producer = &this->parent;
65
66                 // Construct the producer
67                 mlt_producer_init( producer, this );
68
69                 // Override the producer get_frame
70                 producer->get_frame = producer_get_frame;
71
72                 // Define the destructor
73                 producer->close = ( mlt_destructor )mlt_playlist_close;
74                 producer->close_object = this;
75
76                 // Initialise blank
77                 mlt_producer_init( &this->blank, NULL );
78                 mlt_properties_set( MLT_PRODUCER_PROPERTIES( &this->blank ), "mlt_service", "blank" );
79                 mlt_properties_set( MLT_PRODUCER_PROPERTIES( &this->blank ), "resource", "blank" );
80
81                 // Indicate that this producer is a playlist
82                 mlt_properties_set_data( MLT_PLAYLIST_PROPERTIES( this ), "playlist", this, 0, NULL, NULL );
83
84                 // Specify the eof condition
85                 mlt_properties_set( MLT_PLAYLIST_PROPERTIES( this ), "eof", "pause" );
86                 mlt_properties_set( MLT_PLAYLIST_PROPERTIES( this ), "resource", "<playlist>" );
87                 mlt_properties_set( MLT_PLAYLIST_PROPERTIES( this ), "mlt_type", "mlt_producer" );
88                 mlt_properties_set_position( MLT_PLAYLIST_PROPERTIES( this ), "in", 0 );
89                 mlt_properties_set_position( MLT_PLAYLIST_PROPERTIES( this ), "out", -1 );
90                 mlt_properties_set_position( MLT_PLAYLIST_PROPERTIES( this ), "length", 0 );
91
92                 this->size = 10;
93                 this->list = malloc( this->size * sizeof( playlist_entry * ) );
94         }
95         
96         return this;
97 }
98
99 /** Get the producer associated to this playlist.
100 */
101
102 mlt_producer mlt_playlist_producer( mlt_playlist this )
103 {
104         return this != NULL ? &this->parent : NULL;
105 }
106
107 /** Get the service associated to this playlist.
108 */
109
110 mlt_service mlt_playlist_service( mlt_playlist this )
111 {
112         return MLT_PRODUCER_SERVICE( &this->parent );
113 }
114
115 /** Get the propertues associated to this playlist.
116 */
117
118 mlt_properties mlt_playlist_properties( mlt_playlist this )
119 {
120         return MLT_PRODUCER_PROPERTIES( &this->parent );
121 }
122
123 /** Refresh the playlist after a clip has been changed.
124 */
125
126 static int mlt_playlist_virtual_refresh( mlt_playlist this )
127 {
128         // Obtain the properties
129         mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
130
131         // Get the fps of the first producer
132         double fps = mlt_properties_get_double( properties, "first_fps" );
133         int i = 0;
134         mlt_position frame_count = 0;
135
136         for ( i = 0; i < this->count; i ++ )
137         {
138                 // Get the producer
139                 mlt_producer producer = this->list[ i ]->producer;
140                 int current_length = mlt_producer_get_out( producer ) - mlt_producer_get_in( producer ) + 1;
141
142                 // If fps is 0
143                 if ( fps == 0 )
144                 {
145                         // Inherit it from the producer
146                         fps = mlt_producer_get_fps( producer );
147                 }
148                 else if ( fps != mlt_properties_get_double( MLT_PRODUCER_PROPERTIES( producer ), "fps" ) )
149                 {
150                         // Generate a warning for now - the following attempt to fix may fail
151                         fprintf( stderr, "Warning: fps mismatch on playlist producer %d\n", this->count );
152
153                         // It should be safe to impose fps on an image producer, but not necessarily safe for video
154                         mlt_properties_set_double( MLT_PRODUCER_PROPERTIES( producer ), "fps", fps );
155                 }
156
157                 // Check if the length of the producer has changed
158                 if ( this->list[ i ]->frame_in != mlt_producer_get_in( producer ) ||
159                          this->list[ i ]->frame_out != mlt_producer_get_out( producer ) )
160                 {
161                         // This clip should be removed...
162                         if ( current_length < 1 )
163                         {
164                                 this->list[ i ]->frame_in = 0;
165                                 this->list[ i ]->frame_out = -1;
166                                 this->list[ i ]->frame_count = 0;
167                         }
168                         else 
169                         {
170                                 this->list[ i ]->frame_in = mlt_producer_get_in( producer );
171                                 this->list[ i ]->frame_out = mlt_producer_get_out( producer );
172                                 this->list[ i ]->frame_count = current_length;
173                         }
174
175                         // Update the producer_length
176                         this->list[ i ]->producer_length = current_length;
177                 }
178
179                 // Calculate the frame_count
180                 this->list[ i ]->frame_count = ( this->list[ i ]->frame_out - this->list[ i ]->frame_in + 1 ) * this->list[ i ]->repeat;
181
182                 // Update the frame_count for this clip
183                 frame_count += this->list[ i ]->frame_count;
184         }
185
186         // Refresh all properties
187         mlt_properties_set_double( properties, "first_fps", fps );
188         mlt_properties_set_double( properties, "fps", fps == 0 ? 25 : fps );
189         mlt_events_block( properties, properties );
190         mlt_properties_set_position( properties, "length", frame_count );
191         mlt_events_unblock( properties, properties );
192         mlt_properties_set_position( properties, "out", frame_count - 1 );
193
194         return 0;
195 }
196
197 /** Listener for producers on the playlist.
198 */
199
200 static void mlt_playlist_listener( mlt_producer producer, mlt_playlist this )
201 {
202         mlt_playlist_virtual_refresh( this );
203 }
204
205 /** Append to the virtual playlist.
206 */
207
208 static int mlt_playlist_virtual_append( mlt_playlist this, mlt_producer source, mlt_position in, mlt_position out )
209 {
210         mlt_producer producer = NULL;
211         mlt_properties properties = NULL;
212         mlt_properties parent = NULL;
213
214         // If we have a cut, then use the in/out points from the cut
215         if ( mlt_producer_is_blank( source )  )
216         {
217                 // Make sure the blank is long enough to accomodate the length specified
218                 if ( out - in + 1 > mlt_producer_get_length( &this->blank ) )
219                 {
220                         mlt_properties blank_props = MLT_PRODUCER_PROPERTIES( &this->blank );
221                         mlt_events_block( blank_props, blank_props );
222                         mlt_producer_set_in_and_out( &this->blank, in, out );
223                         mlt_events_unblock( blank_props, blank_props );
224                 }
225
226                 // Now make sure the cut comes from this this->blank
227                 if ( source == NULL )
228                 {
229                         producer = mlt_producer_cut( &this->blank, in, out );
230                 }
231                 else if ( !mlt_producer_is_cut( source ) || mlt_producer_cut_parent( source ) != &this->blank )
232                 {
233                         producer = mlt_producer_cut( &this->blank, in, out );
234                 }
235                 else
236                 {
237                         producer = source;
238                         mlt_properties_inc_ref( MLT_PRODUCER_PROPERTIES( producer ) );
239                 }
240
241                 properties = MLT_PRODUCER_PROPERTIES( producer );
242         }
243         else if ( mlt_producer_is_cut( source ) )
244         {
245                 producer = source;
246                 if ( in == -1 )
247                         in = mlt_producer_get_in( producer );
248                 if ( out == -1 || out > mlt_producer_get_out( producer ) )
249                         out = mlt_producer_get_out( producer );
250                 properties = MLT_PRODUCER_PROPERTIES( producer );
251                 mlt_properties_inc_ref( properties );
252         }
253         else
254         {
255                 producer = mlt_producer_cut( source, in, out );
256                 if ( in == -1 || in < mlt_producer_get_in( producer ) )
257                         in = mlt_producer_get_in( producer );
258                 if ( out == -1 || out > mlt_producer_get_out( producer ) )
259                         out = mlt_producer_get_out( producer );
260                 properties = MLT_PRODUCER_PROPERTIES( producer );
261         }
262
263         // Fetch the cuts parent properties
264         parent = MLT_PRODUCER_PROPERTIES( mlt_producer_cut_parent( producer ) );
265
266         // Check that we have room
267         if ( this->count >= this->size )
268         {
269                 int i;
270                 this->list = realloc( this->list, ( this->size + 10 ) * sizeof( playlist_entry * ) );
271                 for ( i = this->size; i < this->size + 10; i ++ ) this->list[ i ] = NULL;
272                 this->size += 10;
273         }
274
275         // Create the entry
276         this->list[ this->count ] = calloc( sizeof( playlist_entry ), 1 );
277         if ( this->list[ this->count ] != NULL )
278         {
279                 this->list[ this->count ]->producer = producer;
280                 this->list[ this->count ]->frame_in = in;
281                 this->list[ this->count ]->frame_out = out;
282                 this->list[ this->count ]->frame_count = out - in + 1;
283                 this->list[ this->count ]->repeat = 1;
284                 this->list[ this->count ]->producer_length = mlt_producer_get_out( producer ) - mlt_producer_get_in( producer ) + 1;
285                 this->list[ this->count ]->event = mlt_events_listen( parent, this, "producer-changed", ( mlt_listener )mlt_playlist_listener );
286                 mlt_event_inc_ref( this->list[ this->count ]->event );
287                 mlt_properties_set( properties, "eof", "pause" );
288                 mlt_producer_set_speed( producer, 0 );
289                 this->count ++;
290         }
291
292         return mlt_playlist_virtual_refresh( this );
293 }
294
295 static mlt_producer mlt_playlist_locate( mlt_playlist this, mlt_position *position, int *clip, int *total )
296 {
297         // Default producer to NULL
298         mlt_producer producer = NULL;
299
300         // Loop for each producer until found
301         for ( *clip = 0; *clip < this->count; *clip += 1 )
302         {
303                 // Increment the total
304                 *total += this->list[ *clip ]->frame_count;
305
306                 // Check if the position indicates that we have found the clip
307                 // Note that 0 length clips get skipped automatically
308                 if ( *position < this->list[ *clip ]->frame_count )
309                 {
310                         // Found it, now break
311                         producer = this->list[ *clip ]->producer;
312                         break;
313                 }
314                 else
315                 {
316                         // Decrement position by length of this entry
317                         *position -= this->list[ *clip ]->frame_count;
318                 }
319         }
320
321         return producer;
322 }
323
324 /** Seek in the virtual playlist.
325 */
326
327 static mlt_service mlt_playlist_virtual_seek( mlt_playlist this, int *progressive )
328 {
329         // Map playlist position to real producer in virtual playlist
330         mlt_position position = mlt_producer_frame( &this->parent );
331
332         // Keep the original position since we change it while iterating through the list
333         mlt_position original = position;
334
335         // Clip index and total
336         int i = 0;
337         int total = 0;
338
339         // Locate the producer for the position
340         mlt_producer producer = mlt_playlist_locate( this, &position, &i, &total );
341
342         // Get the properties
343         mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
344
345         // Get the eof handling
346         char *eof = mlt_properties_get( properties, "eof" );
347
348         // Seek in real producer to relative position
349         if ( producer != NULL )
350         {
351                 int count = this->list[ i ]->frame_count / this->list[ i ]->repeat;
352                 *progressive = count == 1;
353                 mlt_producer_seek( producer, position % count );
354         }
355         else if ( !strcmp( eof, "pause" ) && total > 0 )
356         {
357                 playlist_entry *entry = this->list[ this->count - 1 ];
358                 int count = entry->frame_count / entry->repeat;
359                 mlt_producer this_producer = MLT_PLAYLIST_PRODUCER( this );
360                 mlt_producer_seek( this_producer, original - 1 );
361                 producer = entry->producer;
362                 mlt_producer_seek( producer, entry->frame_out % count );
363                 mlt_producer_set_speed( this_producer, 0 );
364                 mlt_producer_set_speed( producer, 0 );
365                 *progressive = count == 1;
366         }
367         else if ( !strcmp( eof, "loop" ) && total > 0 )
368         {
369                 playlist_entry *entry = this->list[ 0 ];
370                 mlt_producer this_producer = MLT_PLAYLIST_PRODUCER( this );
371                 mlt_producer_seek( this_producer, 0 );
372                 producer = entry->producer;
373                 mlt_producer_seek( producer, 0 );
374         }
375         else
376         {
377                 producer = &this->blank;
378         }
379
380         return MLT_PRODUCER_SERVICE( producer );
381 }
382
383 /** Invoked when a producer indicates that it has prematurely reached its end.
384 */
385
386 static mlt_producer mlt_playlist_virtual_set_out( mlt_playlist this )
387 {
388         // Default producer to blank
389         mlt_producer producer = &this->blank;
390
391         // Map playlist position to real producer in virtual playlist
392         mlt_position position = mlt_producer_frame( &this->parent );
393
394         // Loop through the virtual playlist
395         int i = 0;
396
397         for ( i = 0; i < this->count; i ++ )
398         {
399                 if ( position < this->list[ i ]->frame_count )
400                 {
401                         // Found it, now break
402                         producer = this->list[ i ]->producer;
403                         break;
404                 }
405                 else
406                 {
407                         // Decrement position by length of this entry
408                         position -= this->list[ i ]->frame_count;
409                 }
410         }
411
412         // Seek in real producer to relative position
413         if ( i < this->count && this->list[ i ]->frame_out != position )
414         {
415                 // Update the frame_count for the changed clip (hmmm)
416                 this->list[ i ]->frame_out = position;
417                 this->list[ i ]->frame_count = this->list[ i ]->frame_out - this->list[ i ]->frame_in + 1;
418
419                 // Refresh the playlist
420                 mlt_playlist_virtual_refresh( this );
421         }
422
423         return producer;
424 }
425
426 /** Obtain the current clips index.
427 */
428
429 int mlt_playlist_current_clip( mlt_playlist this )
430 {
431         // Map playlist position to real producer in virtual playlist
432         mlt_position position = mlt_producer_frame( &this->parent );
433
434         // Loop through the virtual playlist
435         int i = 0;
436
437         for ( i = 0; i < this->count; i ++ )
438         {
439                 if ( position < this->list[ i ]->frame_count )
440                 {
441                         // Found it, now break
442                         break;
443                 }
444                 else
445                 {
446                         // Decrement position by length of this entry
447                         position -= this->list[ i ]->frame_count;
448                 }
449         }
450
451         return i;
452 }
453
454 /** Obtain the current clips producer.
455 */
456
457 mlt_producer mlt_playlist_current( mlt_playlist this )
458 {
459         int i = mlt_playlist_current_clip( this );
460         if ( i < this->count )
461                 return this->list[ i ]->producer;
462         else
463                 return &this->blank;
464 }
465
466 /** Get the position which corresponds to the start of the next clip.
467 */
468
469 mlt_position mlt_playlist_clip( mlt_playlist this, mlt_whence whence, int index )
470 {
471         mlt_position position = 0;
472         int absolute_clip = index;
473         int i = 0;
474
475         // Determine the absolute clip
476         switch ( whence )
477         {
478                 case mlt_whence_relative_start:
479                         absolute_clip = index;
480                         break;
481
482                 case mlt_whence_relative_current:
483                         absolute_clip = mlt_playlist_current_clip( this ) + index;
484                         break;
485
486                 case mlt_whence_relative_end:
487                         absolute_clip = this->count - index;
488                         break;
489         }
490
491         // Check that we're in a valid range
492         if ( absolute_clip < 0 )
493                 absolute_clip = 0;
494         else if ( absolute_clip > this->count )
495                 absolute_clip = this->count;
496
497         // Now determine the position
498         for ( i = 0; i < absolute_clip; i ++ )
499                 position += this->list[ i ]->frame_count;
500
501         return position;
502 }
503
504 /** Get all the info about the clip specified.
505 */
506
507 int mlt_playlist_get_clip_info( mlt_playlist this, mlt_playlist_clip_info *info, int index )
508 {
509         int error = index < 0 || index >= this->count;
510         memset( info, 0, sizeof( mlt_playlist_clip_info ) );
511         if ( !error )
512         {
513                 mlt_producer producer = mlt_producer_cut_parent( this->list[ index ]->producer );
514                 mlt_properties properties = MLT_PRODUCER_PROPERTIES( producer );
515                 info->clip = index;
516                 info->producer = producer;
517                 info->cut = this->list[ index ]->producer;
518                 info->start = mlt_playlist_clip( this, mlt_whence_relative_start, index );
519                 info->resource = mlt_properties_get( properties, "resource" );
520                 info->frame_in = this->list[ index ]->frame_in;
521                 info->frame_out = this->list[ index ]->frame_out;
522                 info->frame_count = this->list[ index ]->frame_count;
523                 info->repeat = this->list[ index ]->repeat;
524                 info->length = mlt_producer_get_length( producer );
525                 info->fps = mlt_producer_get_fps( producer );
526         }
527
528         return error;
529 }
530
531 /** Get number of clips in the playlist.
532 */
533
534 int mlt_playlist_count( mlt_playlist this )
535 {
536         return this->count;
537 }
538
539 /** Clear the playlist.
540 */
541
542 int mlt_playlist_clear( mlt_playlist this )
543 {
544         int i;
545         for ( i = 0; i < this->count; i ++ )
546         {
547                 mlt_event_close( this->list[ i ]->event );
548                 mlt_producer_close( this->list[ i ]->producer );
549         }
550         this->count = 0;
551         mlt_properties_set_double( MLT_PLAYLIST_PROPERTIES( this ), "first_fps", 0 );
552         return mlt_playlist_virtual_refresh( this );
553 }
554
555 /** Append a producer to the playlist.
556 */
557
558 int mlt_playlist_append( mlt_playlist this, mlt_producer producer )
559 {
560         // Append to virtual list
561         return mlt_playlist_virtual_append( this, producer, 0, mlt_producer_get_playtime( producer ) - 1 );
562 }
563
564 /** Append a producer to the playlist with in/out points.
565 */
566
567 int mlt_playlist_append_io( mlt_playlist this, mlt_producer producer, mlt_position in, mlt_position out )
568 {
569         // Append to virtual list
570         if ( in != -1 && out != -1 )
571                 return mlt_playlist_virtual_append( this, producer, in, out );
572         else
573                 return mlt_playlist_append( this, producer );
574 }
575
576 /** Append a blank to the playlist of a given length.
577 */
578
579 int mlt_playlist_blank( mlt_playlist this, mlt_position length )
580 {
581         // Append to the virtual list
582         return mlt_playlist_virtual_append( this, &this->blank, 0, length );
583 }
584
585 /** Insert a producer into the playlist.
586 */
587
588 int mlt_playlist_insert( mlt_playlist this, mlt_producer producer, int where, mlt_position in, mlt_position out )
589 {
590         // Append to end
591         mlt_events_block( MLT_PLAYLIST_PROPERTIES( this ), this );
592         mlt_playlist_append_io( this, producer, in, out );
593
594         // Move to the position specified
595         mlt_playlist_move( this, this->count - 1, where );
596         mlt_events_unblock( MLT_PLAYLIST_PROPERTIES( this ), this );
597
598         return mlt_playlist_virtual_refresh( this );
599 }
600
601 /** Remove an entry in the playlist.
602 */
603
604 int mlt_playlist_remove( mlt_playlist this, int where )
605 {
606         int error = where < 0 || where >= this->count;
607         if ( error == 0 && mlt_playlist_unmix( this, where ) != 0 )
608         {
609                 // We need to know the current clip and the position within the playlist
610                 int current = mlt_playlist_current_clip( this );
611                 mlt_position position = mlt_producer_position( MLT_PLAYLIST_PRODUCER( this ) );
612
613                 // We need all the details about the clip we're removing
614                 mlt_playlist_clip_info where_info;
615                 playlist_entry *entry = this->list[ where ];
616                 mlt_properties properties = MLT_PRODUCER_PROPERTIES( entry->producer );
617
618                 // Loop variable
619                 int i = 0;
620
621                 // Get the clip info 
622                 mlt_playlist_get_clip_info( this, &where_info, where );
623
624                 // Make sure the clip to be removed is valid and correct if necessary
625                 if ( where < 0 ) 
626                         where = 0;
627                 if ( where >= this->count )
628                         where = this->count - 1;
629
630                 // Reorganise the list
631                 for ( i = where + 1; i < this->count; i ++ )
632                         this->list[ i - 1 ] = this->list[ i ];
633                 this->count --;
634
635                 if ( entry->preservation_hack == 0 )
636                 {
637                         // Decouple from mix_in/out if necessary
638                         if ( mlt_properties_get_data( properties, "mix_in", NULL ) != NULL )
639                         {
640                                 mlt_properties mix = mlt_properties_get_data( properties, "mix_in", NULL );
641                                 mlt_properties_set_data( mix, "mix_out", NULL, 0, NULL, NULL );
642                         }
643                         if ( mlt_properties_get_data( properties, "mix_out", NULL ) != NULL )
644                         {
645                                 mlt_properties mix = mlt_properties_get_data( properties, "mix_out", NULL );
646                                 mlt_properties_set_data( mix, "mix_in", NULL, 0, NULL, NULL );
647                         }
648         
649                         if ( mlt_properties_ref_count( MLT_PRODUCER_PROPERTIES( entry->producer ) ) == 1 )
650                                 mlt_producer_clear( entry->producer );
651                 }
652
653                 // Close the producer associated to the clip info
654                 mlt_event_close( entry->event );
655                 mlt_producer_close( entry->producer );
656
657                 // Correct position
658                 if ( where == current )
659                         mlt_producer_seek( MLT_PLAYLIST_PRODUCER( this ), where_info.start );
660                 else if ( where < current && this->count > 0 )
661                         mlt_producer_seek( MLT_PLAYLIST_PRODUCER( this ), position - where_info.frame_count );
662                 else if ( this->count == 0 )
663                         mlt_producer_seek( MLT_PLAYLIST_PRODUCER( this ), 0 );
664
665                 // Free the entry
666                 free( entry );
667
668                 // Refresh the playlist
669                 mlt_playlist_virtual_refresh( this );
670         }
671
672         return error;
673 }
674
675 /** Move an entry in the playlist.
676 */
677
678 int mlt_playlist_move( mlt_playlist this, int src, int dest )
679 {
680         int i;
681
682         /* We need to ensure that the requested indexes are valid and correct it as necessary */
683         if ( src < 0 ) 
684                 src = 0;
685         if ( src >= this->count )
686                 src = this->count - 1;
687
688         if ( dest < 0 ) 
689                 dest = 0;
690         if ( dest >= this->count )
691                 dest = this->count - 1;
692         
693         if ( src != dest && this->count > 1 )
694         {
695                 int current = mlt_playlist_current_clip( this );
696                 mlt_position position = mlt_producer_position( MLT_PLAYLIST_PRODUCER( this ) );
697                 playlist_entry *src_entry = NULL;
698
699                 // We need all the details about the current clip
700                 mlt_playlist_clip_info current_info;
701
702                 mlt_playlist_get_clip_info( this, &current_info, current );
703                 position -= current_info.start;
704
705                 if ( current == src )
706                         current = dest;
707                 else if ( current > src && current < dest )
708                         current ++;
709                 else if ( current == dest )
710                         current = src;
711
712                 src_entry = this->list[ src ];
713                 if ( src > dest )
714                 {
715                         for ( i = src; i > dest; i -- )
716                                 this->list[ i ] = this->list[ i - 1 ];
717                 }
718                 else
719                 {
720                         for ( i = src; i < dest; i ++ )
721                                 this->list[ i ] = this->list[ i + 1 ];
722                 }
723                 this->list[ dest ] = src_entry;
724
725                 mlt_playlist_get_clip_info( this, &current_info, current );
726                 mlt_producer_seek( MLT_PLAYLIST_PRODUCER( this ), current_info.start + position );
727                 mlt_playlist_virtual_refresh( this );
728         }
729
730         return 0;
731 }
732
733 /** Repeat the specified clip n times.
734 */
735
736 int mlt_playlist_repeat_clip( mlt_playlist this, int clip, int repeat )
737 {
738         int error = repeat < 1 || clip < 0 || clip >= this->count;
739         if ( error == 0 )
740         {
741                 playlist_entry *entry = this->list[ clip ];
742                 entry->repeat = repeat;
743                 mlt_playlist_virtual_refresh( this );
744         }
745         return error;
746 }
747
748 /** Resize the specified clip.
749 */
750
751 int mlt_playlist_resize_clip( mlt_playlist this, int clip, mlt_position in, mlt_position out )
752 {
753         int error = clip < 0 || clip >= this->count;
754         if ( error == 0 && mlt_playlist_resize_mix( this, clip, in, out ) != 0 )
755         {
756                 playlist_entry *entry = this->list[ clip ];
757                 mlt_producer producer = entry->producer;
758                 mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
759
760                 mlt_events_block( properties, properties );
761
762                 if ( mlt_producer_is_blank( producer ) )
763                 {
764                         // Make sure the blank is long enough to accomodate the length specified
765                         if ( out - in + 1 > mlt_producer_get_length( &this->blank ) )
766                         {
767                                 mlt_properties blank_props = MLT_PRODUCER_PROPERTIES( &this->blank );
768                                 mlt_properties_set_int( blank_props, "length", out - in + 1 );
769                                 mlt_properties_set_int( MLT_PRODUCER_PROPERTIES( producer ), "length", out - in + 1 );
770                                 mlt_producer_set_in_and_out( &this->blank, 0, out - in );
771                         }
772                 }
773
774                 if ( in <= -1 )
775                         in = 0;
776                 if ( out <= -1 || out >= mlt_producer_get_length( producer ) )
777                         out = mlt_producer_get_length( producer ) - 1;
778
779                 if ( out < in )
780                 {
781                         mlt_position t = in;
782                         in = out;
783                         out = t;
784                 }
785
786                 mlt_producer_set_in_and_out( producer, in, out );
787                 mlt_events_unblock( properties, properties );
788                 mlt_playlist_virtual_refresh( this );
789         }
790         return error;
791 }
792
793 /** Split a clip on the playlist at the given position.
794 */
795
796 int mlt_playlist_split( mlt_playlist this, int clip, mlt_position position )
797 {
798         int error = clip < 0 || clip >= this->count;
799         if ( error == 0 )
800         {
801                 playlist_entry *entry = this->list[ clip ];
802                 position = position < 0 ? entry->frame_count + position - 1 : position;
803                 if ( position >= 0 && position < entry->frame_count - 1 )
804                 {
805                         int in = entry->frame_in;
806                         int out = entry->frame_out;
807                         mlt_events_block( MLT_PLAYLIST_PROPERTIES( this ), this );
808                         mlt_playlist_resize_clip( this, clip, in, in + position );
809                         if ( !mlt_producer_is_blank( entry->producer ) )
810                         {
811                                 int i = 0;
812                                 mlt_properties entry_properties = MLT_PRODUCER_PROPERTIES( entry->producer );
813                                 mlt_producer split = mlt_producer_cut( entry->producer, in + position + 1, out );
814                                 mlt_properties split_properties = MLT_PRODUCER_PROPERTIES( split );
815                                 mlt_playlist_insert( this, split, clip + 1, 0, -1 );
816                                 for ( i = 0; i < mlt_properties_count( entry_properties ); i ++ )
817                                 {
818                                         char *name = mlt_properties_get_name( entry_properties, i );
819                                         if ( name != NULL && !strncmp( name, "meta.", 5 ) )
820                                                 mlt_properties_set( split_properties, name, mlt_properties_get_value( entry_properties, i ) );
821                                 }
822                                 mlt_producer_close( split );
823                         }
824                         else
825                         {
826                                 mlt_playlist_insert( this, &this->blank, clip + 1, 0, out - position - 1 );
827                         }
828                         mlt_events_unblock( MLT_PLAYLIST_PROPERTIES( this ), this );
829                         mlt_playlist_virtual_refresh( this );
830                 }
831                 else
832                 {
833                         error = 1;
834                 }
835         }
836         return error;
837 }
838
839 /** Split the playlist at the absolute position.
840 */
841
842 int mlt_playlist_split_at( mlt_playlist this, mlt_position position, int left )
843 {
844         int result = this == NULL ? -1 : 0;
845         if ( !result )
846         {
847                 if ( position >= 0 && position < mlt_producer_get_playtime( MLT_PLAYLIST_PRODUCER( this ) ) )
848                 {
849                         int clip = mlt_playlist_get_clip_index_at( this, position );
850                         mlt_playlist_clip_info info;
851                         mlt_playlist_get_clip_info( this, &info, clip );
852                         if ( left && position != info.start )
853                                 mlt_playlist_split( this, clip, position - info.start - 1 );
854                         else if ( !left )
855                                 mlt_playlist_split( this, clip, position - info.start );
856                         result = position;
857                 }
858                 else if ( position <= 0 )
859                 {
860                         result = 0;
861                 }
862                 else
863                 {
864                         result = mlt_producer_get_playtime( MLT_PLAYLIST_PRODUCER( this ) );
865                 }
866         }
867         return result;
868 }
869
870 /** Join 1 or more consecutive clips.
871 */
872
873 int mlt_playlist_join( mlt_playlist this, int clip, int count, int merge )
874 {
875         int error = clip < 0 || ( clip ) >= this->count;
876         if ( error == 0 )
877         {
878                 int i = clip;
879                 mlt_playlist new_clip = mlt_playlist_init( );
880                 mlt_events_block( MLT_PLAYLIST_PROPERTIES( this ), this );
881                 if ( clip + count >= this->count )
882                         count = this->count - clip;
883                 for ( i = 0; i <= count; i ++ )
884                 {
885                         playlist_entry *entry = this->list[ clip ];
886                         mlt_playlist_append( new_clip, entry->producer );
887                         mlt_playlist_repeat_clip( new_clip, i, entry->repeat );
888                         entry->preservation_hack = 1;
889                         mlt_playlist_remove( this, clip );
890                 }
891                 mlt_events_unblock( MLT_PLAYLIST_PROPERTIES( this ), this );
892                 mlt_playlist_insert( this, MLT_PLAYLIST_PRODUCER( new_clip ), clip, 0, -1 );
893                 mlt_playlist_close( new_clip );
894         }
895         return error;
896 }
897
898 /** Mix consecutive clips for a specified length and apply transition if specified.
899 */
900
901 int mlt_playlist_mix( mlt_playlist this, int clip, int length, mlt_transition transition )
902 {
903         int error = ( clip < 0 || clip + 1 >= this->count );
904         if ( error == 0 )
905         {
906                 playlist_entry *clip_a = this->list[ clip ];
907                 playlist_entry *clip_b = this->list[ clip + 1 ];
908                 mlt_producer track_a = NULL;
909                 mlt_producer track_b = NULL;
910                 mlt_tractor tractor = mlt_tractor_new( );
911                 mlt_events_block( MLT_PLAYLIST_PROPERTIES( this ), this );
912
913                 // Check length is valid for both clips and resize if necessary.
914                 int max_size = clip_a->frame_count > clip_b->frame_count ? clip_a->frame_count : clip_b->frame_count;
915                 length = length > max_size ? max_size : length;
916
917                 // Create the a and b tracks/cuts if necessary - note that no cuts are required if the length matches
918                 if ( length != clip_a->frame_count )
919                         track_a = mlt_producer_cut( clip_a->producer, clip_a->frame_out - length + 1, clip_a->frame_out );
920                 else
921                         track_a = clip_a->producer;
922
923                 if ( length != clip_b->frame_count )
924                         track_b = mlt_producer_cut( clip_b->producer, clip_b->frame_in, clip_b->frame_in + length - 1 );
925                 else
926                         track_b = clip_b->producer;
927
928                 // Set the tracks on the tractor
929                 mlt_tractor_set_track( tractor, track_a, 0 );
930                 mlt_tractor_set_track( tractor, track_b, 1 );
931
932                 // Insert the mix object into the playlist
933                 mlt_playlist_insert( this, MLT_TRACTOR_PRODUCER( tractor ), clip + 1, -1, -1 );
934                 mlt_properties_set_data( MLT_TRACTOR_PROPERTIES( tractor ), "mlt_mix", tractor, 0, NULL, NULL );
935
936                 // Attach the transition
937                 if ( transition != NULL )
938                 {
939                         mlt_field field = mlt_tractor_field( tractor );
940                         mlt_field_plant_transition( field, transition, 0, 1 );
941                         mlt_transition_set_in_and_out( transition, 0, length - 1 );
942                 }
943
944                 // Close our references to the tracks if we created new cuts above (the tracks can still be used here)
945                 if ( track_a != clip_a->producer )
946                         mlt_producer_close( track_a );
947                 if ( track_b != clip_b->producer )
948                         mlt_producer_close( track_b );
949
950                 // Check if we have anything left on the right hand clip
951                 if ( track_b == clip_b->producer )
952                 {
953                         clip_b->preservation_hack = 1;
954                         mlt_playlist_remove( this, clip + 2 );
955                 }
956                 else if ( clip_b->frame_out - clip_b->frame_in > length )
957                 {
958                         mlt_playlist_resize_clip( this, clip + 2, clip_b->frame_in + length, clip_b->frame_out );
959                         mlt_properties_set_data( MLT_PRODUCER_PROPERTIES( clip_b->producer ), "mix_in", tractor, 0, NULL, NULL );
960                         mlt_properties_set_data( MLT_TRACTOR_PROPERTIES( tractor ), "mix_out", clip_b->producer, 0, NULL, NULL );
961                 }
962                 else
963                 {
964                         mlt_producer_clear( clip_b->producer );
965                         mlt_playlist_remove( this, clip + 2 );
966                 }
967
968                 // Check if we have anything left on the left hand clip
969                 if ( track_a == clip_a->producer )
970                 {
971                         clip_a->preservation_hack = 1;
972                         mlt_playlist_remove( this, clip );
973                 }
974                 else if ( clip_a->frame_out - clip_a->frame_in > length )
975                 {
976                         mlt_playlist_resize_clip( this, clip, clip_a->frame_in, clip_a->frame_out - length );
977                         mlt_properties_set_data( MLT_PRODUCER_PROPERTIES( clip_a->producer ), "mix_out", tractor, 0, NULL, NULL );
978                         mlt_properties_set_data( MLT_TRACTOR_PROPERTIES( tractor ), "mix_in", clip_a->producer, 0, NULL, NULL );
979                 }
980                 else
981                 {
982                         mlt_producer_clear( clip_a->producer );
983                         mlt_playlist_remove( this, clip );
984                 }
985
986                 // Unblock and force a fire off of change events to listeners
987                 mlt_events_unblock( MLT_PLAYLIST_PROPERTIES( this ), this );
988                 mlt_playlist_virtual_refresh( this );
989                 mlt_tractor_close( tractor );
990         }
991         return error;
992 }
993
994 /** Add a transition to an existing mix.
995 */
996
997 int mlt_playlist_mix_add( mlt_playlist this, int clip, mlt_transition transition )
998 {
999         mlt_producer producer = mlt_producer_cut_parent( mlt_playlist_get_clip( this, clip ) );
1000         mlt_properties properties = producer != NULL ? MLT_PRODUCER_PROPERTIES( producer ) : NULL;
1001         mlt_tractor tractor = properties != NULL ? mlt_properties_get_data( properties, "mlt_mix", NULL ) : NULL;
1002         int error = transition == NULL || tractor == NULL;
1003         if ( error == 0 )
1004         {
1005                 mlt_field field = mlt_tractor_field( tractor );
1006                 mlt_field_plant_transition( field, transition, 0, 1 );
1007                 mlt_transition_set_in_and_out( transition, 0, this->list[ clip ]->frame_count - 1 );
1008         }
1009         return error;
1010 }
1011
1012 /** Return the clip at the clip index.
1013 */
1014
1015 mlt_producer mlt_playlist_get_clip( mlt_playlist this, int clip )
1016 {
1017         if ( clip >= 0 && clip < this->count )
1018                 return this->list[ clip ]->producer;
1019         return NULL;
1020 }
1021
1022 /** Return the clip at the specified position.
1023 */
1024
1025 mlt_producer mlt_playlist_get_clip_at( mlt_playlist this, int position )
1026 {
1027         int index = 0, total = 0;
1028         return mlt_playlist_locate( this, &position, &index, &total );
1029 }
1030
1031 /** Return the clip index of the specified position.
1032 */
1033
1034 int mlt_playlist_get_clip_index_at( mlt_playlist this, int position )
1035 {
1036         int index = 0, total = 0;
1037         mlt_playlist_locate( this, &position, &index, &total );
1038         return index;
1039 }
1040
1041 /** Determine if the clip is a mix.
1042 */
1043
1044 int mlt_playlist_clip_is_mix( mlt_playlist this, int clip )
1045 {
1046         mlt_producer producer = mlt_producer_cut_parent( mlt_playlist_get_clip( this, clip ) );
1047         mlt_properties properties = producer != NULL ? MLT_PRODUCER_PROPERTIES( producer ) : NULL;
1048         mlt_tractor tractor = properties != NULL ? mlt_properties_get_data( properties, "mlt_mix", NULL ) : NULL;
1049         return tractor != NULL;
1050 }
1051
1052 /** Remove a mixed clip - ensure that the cuts included in the mix find their way
1053         back correctly on to the playlist.
1054 */
1055
1056 static int mlt_playlist_unmix( mlt_playlist this, int clip )
1057 {
1058         int error = ( clip < 0 || clip >= this->count ); 
1059
1060         // Ensure that the clip request is actually a mix
1061         if ( error == 0 )
1062         {
1063                 mlt_producer producer = mlt_producer_cut_parent( this->list[ clip ]->producer );
1064                 mlt_properties properties = MLT_PRODUCER_PROPERTIES( producer );
1065                 error = mlt_properties_get_data( properties, "mlt_mix", NULL ) == NULL ||
1066                             this->list[ clip ]->preservation_hack;
1067         }
1068
1069         if ( error == 0 )
1070         {
1071                 playlist_entry *mix = this->list[ clip ];
1072                 mlt_tractor tractor = ( mlt_tractor )mlt_producer_cut_parent( mix->producer );
1073                 mlt_properties properties = MLT_TRACTOR_PROPERTIES( tractor );
1074                 mlt_producer clip_a = mlt_properties_get_data( properties, "mix_in", NULL );
1075                 mlt_producer clip_b = mlt_properties_get_data( properties, "mix_out", NULL );
1076                 int length = mlt_producer_get_playtime( MLT_TRACTOR_PRODUCER( tractor ) );
1077                 mlt_events_block( MLT_PLAYLIST_PROPERTIES( this ), this );
1078
1079                 if ( clip_a != NULL )
1080                 {
1081                         mlt_producer_set_in_and_out( clip_a, mlt_producer_get_in( clip_a ), mlt_producer_get_out( clip_a ) + length );
1082                 }
1083                 else
1084                 {
1085                         mlt_producer cut = mlt_tractor_get_track( tractor, 0 );
1086                         mlt_playlist_insert( this, cut, clip, -1, -1 );
1087                         clip ++;
1088                 }
1089
1090                 if ( clip_b != NULL )
1091                 {
1092                         mlt_producer_set_in_and_out( clip_b, mlt_producer_get_in( clip_b ) - length, mlt_producer_get_out( clip_b ) );
1093                 }
1094                 else
1095                 {
1096                         mlt_producer cut = mlt_tractor_get_track( tractor, 1 );
1097                         mlt_playlist_insert( this, cut, clip + 1, -1, -1 );
1098                 }
1099
1100                 mlt_properties_set_data( properties, "mlt_mix", NULL, 0, NULL, NULL );
1101                 mlt_playlist_remove( this, clip );
1102                 mlt_events_unblock( MLT_PLAYLIST_PROPERTIES( this ), this );
1103                 mlt_playlist_virtual_refresh( this );
1104         }
1105         return error;
1106 }
1107
1108 static int mlt_playlist_resize_mix( mlt_playlist this, int clip, int in, int out )
1109 {
1110         int error = ( clip < 0 || clip >= this->count ); 
1111
1112         // Ensure that the clip request is actually a mix
1113         if ( error == 0 )
1114         {
1115                 mlt_producer producer = mlt_producer_cut_parent( this->list[ clip ]->producer );
1116                 mlt_properties properties = MLT_PRODUCER_PROPERTIES( producer );
1117                 error = mlt_properties_get_data( properties, "mlt_mix", NULL ) == NULL;
1118         }
1119
1120         if ( error == 0 )
1121         {
1122                 playlist_entry *mix = this->list[ clip ];
1123                 mlt_tractor tractor = ( mlt_tractor )mlt_producer_cut_parent( mix->producer );
1124                 mlt_properties properties = MLT_TRACTOR_PROPERTIES( tractor );
1125                 mlt_producer clip_a = mlt_properties_get_data( properties, "mix_in", NULL );
1126                 mlt_producer clip_b = mlt_properties_get_data( properties, "mix_out", NULL );
1127                 mlt_producer track_a = mlt_tractor_get_track( tractor, 0 );
1128                 mlt_producer track_b = mlt_tractor_get_track( tractor, 1 );
1129                 int length = out - in + 1;
1130                 int length_diff = length - mlt_producer_get_playtime( MLT_TRACTOR_PRODUCER( tractor ) );
1131                 mlt_events_block( MLT_PLAYLIST_PROPERTIES( this ), this );
1132
1133                 if ( clip_a != NULL )
1134                         mlt_producer_set_in_and_out( clip_a, mlt_producer_get_in( clip_a ), mlt_producer_get_out( clip_a ) - length_diff );
1135
1136                 if ( clip_b != NULL )
1137                         mlt_producer_set_in_and_out( clip_b, mlt_producer_get_in( clip_b ) + length_diff, mlt_producer_get_out( clip_b ) );
1138
1139                 mlt_producer_set_in_and_out( track_a, mlt_producer_get_in( track_a ) - length_diff, mlt_producer_get_out( track_a ) );
1140                 mlt_producer_set_in_and_out( track_b, mlt_producer_get_in( track_b ), mlt_producer_get_out( track_b ) + length_diff );
1141                 mlt_producer_set_in_and_out( MLT_MULTITRACK_PRODUCER( mlt_tractor_multitrack( tractor ) ), in, out );
1142                 mlt_producer_set_in_and_out( MLT_TRACTOR_PRODUCER( tractor ), in, out );
1143                 mlt_properties_set_position( MLT_PRODUCER_PROPERTIES( mix->producer ), "length", out - in + 1 );
1144                 mlt_producer_set_in_and_out( mix->producer, in, out );
1145
1146                 mlt_events_unblock( MLT_PLAYLIST_PROPERTIES( this ), this );
1147                 mlt_playlist_virtual_refresh( this );
1148         }
1149         return error;
1150 }
1151
1152 /** Consolodate adjacent blank producers.
1153 */
1154
1155 void mlt_playlist_consolidate_blanks( mlt_playlist this, int keep_length )
1156 {
1157         if ( this != NULL )
1158         {
1159                 int i = 0;
1160                 mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
1161
1162                 mlt_events_block( properties, properties );
1163                 for ( i = 1; i < this->count; i ++ )
1164                 {
1165                         playlist_entry *left = this->list[ i - 1 ];
1166                         playlist_entry *right = this->list[ i ];
1167
1168                         if ( mlt_producer_is_blank( left->producer ) && mlt_producer_is_blank( right->producer ) )
1169                         {
1170                                 mlt_playlist_resize_clip( this, i - 1, 0, left->frame_count + right->frame_count - 1 );
1171                                 mlt_playlist_remove( this, i -- );
1172                         }
1173                 }
1174
1175                 if ( !keep_length && this->count > 0 )
1176                 {
1177                         playlist_entry *last = this->list[ this->count - 1 ];
1178                         if ( mlt_producer_is_blank( last->producer ) )
1179                                 mlt_playlist_remove( this, this->count - 1 );
1180                 }
1181
1182                 mlt_events_unblock( properties, properties );
1183                 mlt_playlist_virtual_refresh( this );
1184         }
1185 }
1186
1187 /** Determine if the specified clip index is a blank.
1188 */
1189
1190 int mlt_playlist_is_blank( mlt_playlist this, int clip )
1191 {
1192         return this == NULL || mlt_producer_is_blank( mlt_playlist_get_clip( this, clip ) );
1193 }
1194
1195 /** Determine if the specified position is a blank.
1196 */
1197
1198 int mlt_playlist_is_blank_at( mlt_playlist this, int position )
1199 {
1200         return this == NULL || mlt_producer_is_blank( mlt_playlist_get_clip_at( this, position ) );
1201 }
1202
1203 /** Replace the specified clip with a blank and return the clip.
1204 */
1205
1206 mlt_producer mlt_playlist_replace_with_blank( mlt_playlist this, int clip )
1207 {
1208         mlt_producer producer = NULL;
1209         if ( !mlt_playlist_is_blank( this, clip ) )
1210         {
1211                 playlist_entry *entry = this->list[ clip ];
1212                 int in = entry->frame_in;
1213                 int out = entry->frame_out;
1214                 mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
1215                 producer = entry->producer;
1216                 mlt_properties_inc_ref( MLT_PRODUCER_PROPERTIES( producer ) );
1217                 mlt_events_block( properties, properties );
1218                 mlt_playlist_remove( this, clip );
1219                 mlt_playlist_blank( this, out - in );
1220                 mlt_playlist_move( this, this->count - 1, clip );
1221                 mlt_events_unblock( properties, properties );
1222                 mlt_playlist_virtual_refresh( this );
1223                 mlt_producer_set_in_and_out( producer, in, out );
1224         }
1225         return producer;
1226 }
1227
1228 void mlt_playlist_insert_blank( mlt_playlist this, int clip, int length )
1229 {
1230         if ( this != NULL && length >= 0 )
1231         {
1232                 mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
1233                 mlt_events_block( properties, properties );
1234                 mlt_playlist_blank( this, length );
1235                 mlt_playlist_move( this, this->count - 1, clip );
1236                 mlt_events_unblock( properties, properties );
1237                 mlt_playlist_virtual_refresh( this );
1238         }
1239 }
1240
1241 void mlt_playlist_pad_blanks( mlt_playlist this, int position, int length, int find )
1242 {
1243         if ( this != NULL && length != 0 )
1244         {
1245                 int clip = mlt_playlist_get_clip_index_at( this, position );
1246                 mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
1247                 mlt_events_block( properties, properties );
1248                 if ( find && clip < this->count && !mlt_playlist_is_blank( this, clip ) )
1249                         clip ++;
1250                 if ( clip < this->count && mlt_playlist_is_blank( this, clip ) )
1251                 {
1252                         mlt_playlist_clip_info info;
1253                         mlt_playlist_get_clip_info( this, &info, clip );
1254                         if ( info.frame_out + length > info.frame_in )
1255                                 mlt_playlist_resize_clip( this, clip, info.frame_in, info.frame_out + length );
1256                         else
1257                                 mlt_playlist_remove( this, clip );
1258                 }
1259                 else if ( find && clip < this->count && length > 0  )
1260                 {
1261                         mlt_playlist_insert_blank( this, clip, length );
1262                 }
1263                 mlt_events_unblock( properties, properties );
1264                 mlt_playlist_virtual_refresh( this );
1265         }
1266 }
1267
1268 int mlt_playlist_insert_at( mlt_playlist this, int position, mlt_producer producer, int mode )
1269 {
1270         int ret = this == NULL || position < 0 || producer == NULL;
1271         if ( ret == 0 )
1272         {
1273                 mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
1274                 int length = mlt_producer_get_playtime( producer );
1275                 int clip = mlt_playlist_get_clip_index_at( this, position );
1276                 mlt_playlist_clip_info info;
1277                 mlt_playlist_get_clip_info( this, &info, clip );
1278                 mlt_events_block( properties, this );
1279                 if ( clip < this->count && mlt_playlist_is_blank( this, clip ) )
1280                 {
1281                         // Split and move to new clip if need be
1282                         if ( position != info.start && mlt_playlist_split( this, clip, position - info.start ) == 0 )
1283                                 mlt_playlist_get_clip_info( this, &info, ++ clip );
1284
1285                         // Split again if need be
1286                         if ( length < info.frame_count )
1287                                 mlt_playlist_split( this, clip, length - 1 );
1288
1289                         // Remove
1290                         mlt_playlist_remove( this, clip );
1291
1292                         // Insert
1293                         mlt_playlist_insert( this, producer, clip, -1, -1 );
1294                         ret = clip;
1295                 }
1296                 else if ( clip < this->count )
1297                 {
1298                         if ( position > info.start + info.frame_count / 2 )
1299                                 clip ++;
1300                         if ( mode == 1 && clip < this->count && mlt_playlist_is_blank( this, clip ) )
1301                         {
1302                                 mlt_playlist_get_clip_info( this, &info, clip );
1303                                 if ( length < info.frame_count )
1304                                         mlt_playlist_split( this, clip, length );
1305                                 mlt_playlist_remove( this, clip );
1306                         }
1307                         mlt_playlist_insert( this, producer, clip, -1, -1 );
1308                         ret = clip;
1309                 }
1310                 else 
1311                 {
1312                         if ( mode == 1 )
1313                                 mlt_playlist_blank( this, position - mlt_properties_get_int( properties, "length" ) );
1314                         mlt_playlist_append( this, producer );
1315                         ret = this->count - 1;
1316                 }
1317                 mlt_events_unblock( properties, this );
1318                 mlt_playlist_virtual_refresh( this );
1319         }
1320         else
1321         {
1322                 ret = -1;
1323         }
1324         return ret;
1325 }
1326
1327 int mlt_playlist_clip_start( mlt_playlist this, int clip )
1328 {
1329         mlt_playlist_clip_info info;
1330         if ( mlt_playlist_get_clip_info( this, &info, clip ) == 0 )
1331                 return info.start;
1332         return 0;
1333 }
1334
1335 int mlt_playlist_clip_length( mlt_playlist this, int clip )
1336 {
1337         mlt_playlist_clip_info info;
1338         if ( mlt_playlist_get_clip_info( this, &info, clip ) == 0 )
1339                 return info.frame_count;
1340         return 0;
1341 }
1342
1343 int mlt_playlist_blanks_from( mlt_playlist this, int clip, int bounded )
1344 {
1345         int count = 0;
1346         mlt_playlist_clip_info info;
1347         if ( this != NULL && clip < this->count )
1348         {
1349                 mlt_playlist_get_clip_info( this, &info, clip );
1350                 if ( mlt_playlist_is_blank( this, clip ) )
1351                         count += info.frame_count;
1352                 if ( bounded == 0 )
1353                         bounded = this->count;
1354                 for ( clip ++; clip < this->count && bounded >= 0; clip ++ )
1355                 {
1356                         mlt_playlist_get_clip_info( this, &info, clip );
1357                         if ( mlt_playlist_is_blank( this, clip ) )
1358                                 count += info.frame_count;
1359                         else
1360                                 bounded --;
1361                 }
1362         }
1363         return count;
1364 }
1365
1366 int mlt_playlist_remove_region( mlt_playlist this, int position, int length )
1367 {
1368         int index = mlt_playlist_get_clip_index_at( this, position );
1369         if ( index >= 0 && index < this->count )
1370         {
1371                 mlt_properties properties = MLT_PLAYLIST_PROPERTIES( this );
1372                 int clip_start = mlt_playlist_clip_start( this, index );
1373                 int clip_length = mlt_playlist_clip_length( this, index );
1374                 int list_length = mlt_producer_get_playtime( MLT_PLAYLIST_PRODUCER( this ) );
1375                 mlt_events_block( properties, this );
1376
1377                 if ( position + length > list_length )
1378                         length -= ( position + length - list_length );
1379
1380                 if ( clip_start < position )
1381                 {
1382                         mlt_playlist_split( this, index ++, position - clip_start );
1383                         clip_length -= position - clip_start;
1384                 }
1385
1386                 while( length > 0 )
1387                 {
1388                         if ( mlt_playlist_clip_length( this, index ) > length )
1389                                 mlt_playlist_split( this, index, length );
1390                         length -= mlt_playlist_clip_length( this, index );
1391                         mlt_playlist_remove( this, index );
1392                 }
1393         
1394                 mlt_playlist_consolidate_blanks( this, 0 );
1395                 mlt_events_unblock( properties, this );
1396                 mlt_playlist_virtual_refresh( this );
1397
1398                 // Just to be sure, we'll get the clip index again...
1399                 index = mlt_playlist_get_clip_index_at( this, position );
1400         }
1401         return index;
1402 }
1403
1404 int mlt_playlist_move_region( mlt_playlist this, int position, int length, int new_position )
1405 {
1406         if ( this != NULL )
1407         {
1408         }
1409         return 0;
1410 }
1411
1412 /** Get the current frame.
1413 */
1414
1415 static int producer_get_frame( mlt_producer producer, mlt_frame_ptr frame, int index )
1416 {
1417         // Check that we have a producer
1418         if ( producer == NULL )
1419         {
1420                 *frame = mlt_frame_init( );
1421                 return 0;
1422         }
1423
1424         // Get this mlt_playlist
1425         mlt_playlist this = producer->child;
1426
1427         // Need to ensure the frame is deinterlaced when repeating 1 frame
1428         int progressive = 0;
1429
1430         // Get the real producer
1431         mlt_service real = mlt_playlist_virtual_seek( this, &progressive );
1432
1433         // Check that we have a producer
1434         if ( real == NULL )
1435         {
1436                 *frame = mlt_frame_init( );
1437                 return 0;
1438         }
1439
1440         // Get the frame
1441         mlt_service_get_frame( real, frame, index );
1442
1443         // Check if we're at the end of the clip
1444         mlt_properties properties = MLT_FRAME_PROPERTIES( *frame );
1445         if ( mlt_properties_get_int( properties, "end_of_clip" ) )
1446                 mlt_playlist_virtual_set_out( this );
1447
1448         // Set the consumer progressive property
1449         if ( progressive )
1450         {
1451                 mlt_properties_set_int( properties, "consumer_deinterlace", progressive );
1452                 mlt_properties_set_int( properties, "test_audio", 1 );
1453         }
1454
1455         // Check for notifier and call with appropriate argument
1456         mlt_properties playlist_properties = MLT_PRODUCER_PROPERTIES( producer );
1457         void ( *notifier )( void * ) = mlt_properties_get_data( playlist_properties, "notifier", NULL );
1458         if ( notifier != NULL )
1459         {
1460                 void *argument = mlt_properties_get_data( playlist_properties, "notifier_arg", NULL );
1461                 notifier( argument );
1462         }
1463
1464         // Update position on the frame we're creating
1465         mlt_frame_set_position( *frame, mlt_producer_frame( producer ) );
1466
1467         // Position ourselves on the next frame
1468         mlt_producer_prepare_next( producer );
1469
1470         return 0;
1471 }
1472
1473 /** Close the playlist.
1474 */
1475
1476 void mlt_playlist_close( mlt_playlist this )
1477 {
1478         if ( this != NULL && mlt_properties_dec_ref( MLT_PLAYLIST_PROPERTIES( this ) ) <= 0 )
1479         {
1480                 int i = 0;
1481                 this->parent.close = NULL;
1482                 for ( i = 0; i < this->count; i ++ )
1483                 {
1484                         mlt_event_close( this->list[ i ]->event );
1485                         mlt_producer_close( this->list[ i ]->producer );
1486                         free( this->list[ i ] );
1487                 }
1488                 mlt_producer_close( &this->blank );
1489                 mlt_producer_close( &this->parent );
1490                 free( this->list );
1491                 free( this );
1492         }
1493 }