More automated renaming.
[dcpomatic.git] / src / lib / ffmpeg_content.cc
1 /*
2     Copyright (C) 2013-2016 Carl Hetherington <cth@carlh.net>
3
4     This file is part of DCP-o-matic.
5
6     DCP-o-matic 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     DCP-o-matic 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 DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
18
19 */
20
21 #include "ffmpeg_content.h"
22 #include "video_content.h"
23 #include "audio_content.h"
24 #include "ffmpeg_examiner.h"
25 #include "ffmpeg_subtitle_stream.h"
26 #include "ffmpeg_audio_stream.h"
27 #include "compose.hpp"
28 #include "job.h"
29 #include "util.h"
30 #include "filter.h"
31 #include "film.h"
32 #include "log.h"
33 #include "exceptions.h"
34 #include "frame_rate_change.h"
35 #include "text_content.h"
36 #include <dcp/raw_convert.h>
37 #include <libcxml/cxml.h>
38 extern "C" {
39 #include <libavformat/avformat.h>
40 #include <libavutil/pixdesc.h>
41 }
42 #include <libxml++/libxml++.h>
43 #include <boost/foreach.hpp>
44 #include <iostream>
45
46 #include "i18n.h"
47
48 #define LOG_GENERAL(...) film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_GENERAL);
49
50 using std::string;
51 using std::vector;
52 using std::list;
53 using std::cout;
54 using std::pair;
55 using std::make_pair;
56 using std::max;
57 using boost::shared_ptr;
58 using boost::dynamic_pointer_cast;
59 using boost::optional;
60 using dcp::raw_convert;
61
62 int const FFmpegContentProperty::SUBTITLE_STREAMS = 100;
63 int const FFmpegContentProperty::SUBTITLE_STREAM = 101;
64 int const FFmpegContentProperty::FILTERS = 102;
65
66 FFmpegContent::FFmpegContent (shared_ptr<const Film> film, boost::filesystem::path p)
67         : Content (film, p)
68 {
69
70 }
71
72 template <class T>
73 optional<T>
74 get_optional_enum (cxml::ConstNodePtr node, string name)
75 {
76         optional<int> const v = node->optional_number_child<int>(name);
77         if (!v) {
78                 return optional<T>();
79         }
80         return static_cast<T>(*v);
81 }
82
83 FFmpegContent::FFmpegContent (shared_ptr<const Film> film, cxml::ConstNodePtr node, int version, list<string>& notes)
84         : Content (film, node)
85 {
86         video = VideoContent::from_xml (this, node, version);
87         audio = AudioContent::from_xml (this, node, version);
88         caption = TextContent::from_xml (this, node, version);
89
90         list<cxml::NodePtr> c = node->node_children ("SubtitleStream");
91         for (list<cxml::NodePtr>::const_iterator i = c.begin(); i != c.end(); ++i) {
92                 _subtitle_streams.push_back (shared_ptr<FFmpegSubtitleStream> (new FFmpegSubtitleStream (*i, version)));
93                 if ((*i)->optional_number_child<int> ("Selected")) {
94                         _subtitle_stream = _subtitle_streams.back ();
95                 }
96         }
97
98         c = node->node_children ("AudioStream");
99         for (list<cxml::NodePtr>::const_iterator i = c.begin(); i != c.end(); ++i) {
100                 shared_ptr<FFmpegAudioStream> as (new FFmpegAudioStream (*i, version));
101                 audio->add_stream (as);
102                 if (version < 11 && !(*i)->optional_node_child ("Selected")) {
103                         /* This is an old file and this stream is not selected, so un-map it */
104                         as->set_mapping (AudioMapping (as->channels (), MAX_DCP_AUDIO_CHANNELS));
105                 }
106         }
107
108         c = node->node_children ("Filter");
109         for (list<cxml::NodePtr>::iterator i = c.begin(); i != c.end(); ++i) {
110                 Filter const * f = Filter::from_id ((*i)->content ());
111                 if (f) {
112                         _filters.push_back (f);
113                 } else {
114                         notes.push_back (String::compose (_("DCP-o-matic no longer supports the `%1' filter, so it has been turned off."), (*i)->content()));
115                 }
116         }
117
118         optional<ContentTime::Type> const f = node->optional_number_child<ContentTime::Type> ("FirstVideo");
119         if (f) {
120                 _first_video = ContentTime (f.get ());
121         }
122
123         _color_range = get_optional_enum<AVColorRange>(node, "ColorRange");
124         _color_primaries = get_optional_enum<AVColorPrimaries>(node, "ColorPrimaries");
125         _color_trc = get_optional_enum<AVColorTransferCharacteristic>(node, "ColorTransferCharacteristic");
126         _colorspace = get_optional_enum<AVColorSpace>(node, "Colorspace");
127         _bits_per_pixel = node->optional_number_child<int> ("BitsPerPixel");
128
129 }
130
131 FFmpegContent::FFmpegContent (shared_ptr<const Film> film, vector<shared_ptr<Content> > c)
132         : Content (film, c)
133 {
134         vector<shared_ptr<Content> >::const_iterator i = c.begin ();
135
136         bool need_video = false;
137         bool need_audio = false;
138         bool need_caption = false;
139
140         if (i != c.end ()) {
141                 need_video = static_cast<bool> ((*i)->video);
142                 need_audio = static_cast<bool> ((*i)->audio);
143                 need_caption = !(*i)->caption.empty();
144         }
145
146         while (i != c.end ()) {
147                 if (need_video != static_cast<bool> ((*i)->video)) {
148                         throw JoinError (_("Content to be joined must all have or not have video"));
149                 }
150                 if (need_audio != static_cast<bool> ((*i)->audio)) {
151                         throw JoinError (_("Content to be joined must all have or not have audio"));
152                 }
153                 if (need_caption != !(*i)->caption.empty()) {
154                         throw JoinError (_("Content to be joined must all have or not have captions"));
155                 }
156                 ++i;
157         }
158
159         if (need_video) {
160                 video.reset (new VideoContent (this, c));
161         }
162         if (need_audio) {
163                 audio.reset (new AudioContent (this, c));
164         }
165         if (need_caption) {
166                 caption.push_back (shared_ptr<TextContent> (new TextContent (this, c)));
167         }
168
169         shared_ptr<FFmpegContent> ref = dynamic_pointer_cast<FFmpegContent> (c[0]);
170         DCPOMATIC_ASSERT (ref);
171
172         for (size_t i = 0; i < c.size(); ++i) {
173                 shared_ptr<FFmpegContent> fc = dynamic_pointer_cast<FFmpegContent> (c[i]);
174                 if (fc->only_caption() && fc->only_caption()->use() && *(fc->_subtitle_stream.get()) != *(ref->_subtitle_stream.get())) {
175                         throw JoinError (_("Content to be joined must use the same subtitle stream."));
176                 }
177         }
178
179         /* XXX: should probably check that more of the stuff below is the same in *this and ref */
180
181         _subtitle_streams = ref->subtitle_streams ();
182         _subtitle_stream = ref->subtitle_stream ();
183         _first_video = ref->_first_video;
184         _filters = ref->_filters;
185         _color_range = ref->_color_range;
186         _color_primaries = ref->_color_primaries;
187         _color_trc = ref->_color_trc;
188         _colorspace = ref->_colorspace;
189         _bits_per_pixel = ref->_bits_per_pixel;
190 }
191
192 void
193 FFmpegContent::as_xml (xmlpp::Node* node, bool with_paths) const
194 {
195         node->add_child("Type")->add_child_text ("FFmpeg");
196         Content::as_xml (node, with_paths);
197
198         if (video) {
199                 video->as_xml (node);
200         }
201
202         if (audio) {
203                 audio->as_xml (node);
204
205                 BOOST_FOREACH (AudioStreamPtr i, audio->streams ()) {
206                         shared_ptr<FFmpegAudioStream> f = dynamic_pointer_cast<FFmpegAudioStream> (i);
207                         DCPOMATIC_ASSERT (f);
208                         f->as_xml (node->add_child("AudioStream"));
209                 }
210         }
211
212         if (only_caption()) {
213                 only_caption()->as_xml (node);
214         }
215
216         boost::mutex::scoped_lock lm (_mutex);
217
218         for (vector<shared_ptr<FFmpegSubtitleStream> >::const_iterator i = _subtitle_streams.begin(); i != _subtitle_streams.end(); ++i) {
219                 xmlpp::Node* t = node->add_child("SubtitleStream");
220                 if (_subtitle_stream && *i == _subtitle_stream) {
221                         t->add_child("Selected")->add_child_text("1");
222                 }
223                 (*i)->as_xml (t);
224         }
225
226         for (vector<Filter const *>::const_iterator i = _filters.begin(); i != _filters.end(); ++i) {
227                 node->add_child("Filter")->add_child_text ((*i)->id ());
228         }
229
230         if (_first_video) {
231                 node->add_child("FirstVideo")->add_child_text (raw_convert<string> (_first_video.get().get()));
232         }
233
234         if (_color_range) {
235                 node->add_child("ColorRange")->add_child_text (raw_convert<string> (static_cast<int> (*_color_range)));
236         }
237         if (_color_primaries) {
238                 node->add_child("ColorPrimaries")->add_child_text (raw_convert<string> (static_cast<int> (*_color_primaries)));
239         }
240         if (_color_trc) {
241                 node->add_child("ColorTransferCharacteristic")->add_child_text (raw_convert<string> (static_cast<int> (*_color_trc)));
242         }
243         if (_colorspace) {
244                 node->add_child("Colorspace")->add_child_text (raw_convert<string> (static_cast<int> (*_colorspace)));
245         }
246         if (_bits_per_pixel) {
247                 node->add_child("BitsPerPixel")->add_child_text (raw_convert<string> (*_bits_per_pixel));
248         }
249 }
250
251 void
252 FFmpegContent::examine (shared_ptr<Job> job)
253 {
254         job->set_progress_unknown ();
255
256         Content::examine (job);
257
258         shared_ptr<FFmpegExaminer> examiner (new FFmpegExaminer (shared_from_this (), job));
259
260         if (examiner->has_video ()) {
261                 video.reset (new VideoContent (this));
262                 video->take_from_examiner (examiner);
263         }
264
265         boost::filesystem::path first_path = path (0);
266
267         {
268                 boost::mutex::scoped_lock lm (_mutex);
269
270                 if (examiner->has_video ()) {
271                         _first_video = examiner->first_video ();
272                         _color_range = examiner->color_range ();
273                         _color_primaries = examiner->color_primaries ();
274                         _color_trc = examiner->color_trc ();
275                         _colorspace = examiner->colorspace ();
276                         _bits_per_pixel = examiner->bits_per_pixel ();
277
278                         if (examiner->rotation()) {
279                                 double rot = *examiner->rotation ();
280                                 if (fabs (rot - 180) < 1.0) {
281                                         _filters.push_back (Filter::from_id ("vflip"));
282                                         _filters.push_back (Filter::from_id ("hflip"));
283                                 } else if (fabs (rot - 90) < 1.0) {
284                                         _filters.push_back (Filter::from_id ("90clock"));
285                                 } else if (fabs (rot - 270) < 1.0) {
286                                         _filters.push_back (Filter::from_id ("90anticlock"));
287                                 }
288                         }
289                 }
290
291                 if (!examiner->audio_streams().empty ()) {
292                         audio.reset (new AudioContent (this));
293
294                         BOOST_FOREACH (shared_ptr<FFmpegAudioStream> i, examiner->audio_streams ()) {
295                                 audio->add_stream (i);
296                         }
297
298                         AudioStreamPtr as = audio->streams().front();
299                         AudioMapping m = as->mapping ();
300                         film()->make_audio_mapping_default (m, first_path);
301                         as->set_mapping (m);
302                 }
303
304                 _subtitle_streams = examiner->subtitle_streams ();
305                 if (!_subtitle_streams.empty ()) {
306                         caption.clear ();
307                         caption.push_back (shared_ptr<TextContent> (new TextContent (this, CAPTION_OPEN)));
308                         _subtitle_stream = _subtitle_streams.front ();
309                 }
310
311         }
312
313         if (examiner->has_video ()) {
314                 set_default_colour_conversion ();
315         }
316
317         signal_changed (FFmpegContentProperty::SUBTITLE_STREAMS);
318         signal_changed (FFmpegContentProperty::SUBTITLE_STREAM);
319 }
320
321 string
322 FFmpegContent::summary () const
323 {
324         if (video && audio) {
325                 return String::compose (_("%1 [movie]"), path_summary ());
326         } else if (video) {
327                 return String::compose (_("%1 [video]"), path_summary ());
328         } else if (audio) {
329                 return String::compose (_("%1 [audio]"), path_summary ());
330         }
331
332         return path_summary ();
333 }
334
335 string
336 FFmpegContent::technical_summary () const
337 {
338         string as = "";
339         BOOST_FOREACH (shared_ptr<FFmpegAudioStream> i, ffmpeg_audio_streams ()) {
340                 as += i->technical_summary () + " " ;
341         }
342
343         if (as.empty ()) {
344                 as = "none";
345         }
346
347         string ss = "none";
348         if (_subtitle_stream) {
349                 ss = _subtitle_stream->technical_summary ();
350         }
351
352         string filt = Filter::ffmpeg_string (_filters);
353
354         string s = Content::technical_summary ();
355
356         if (video) {
357                 s += " - " + video->technical_summary ();
358         }
359
360         if (audio) {
361                 s += " - " + audio->technical_summary ();
362         }
363
364         return s + String::compose (
365                 "ffmpeg: audio %1 subtitle %2 filters %3", as, ss, filt
366                 );
367 }
368
369 void
370 FFmpegContent::set_subtitle_stream (shared_ptr<FFmpegSubtitleStream> s)
371 {
372         {
373                 boost::mutex::scoped_lock lm (_mutex);
374                 _subtitle_stream = s;
375         }
376
377         signal_changed (FFmpegContentProperty::SUBTITLE_STREAM);
378 }
379
380 bool
381 operator== (FFmpegStream const & a, FFmpegStream const & b)
382 {
383         return a._id == b._id;
384 }
385
386 bool
387 operator!= (FFmpegStream const & a, FFmpegStream const & b)
388 {
389         return a._id != b._id;
390 }
391
392 DCPTime
393 FFmpegContent::full_length () const
394 {
395         FrameRateChange const frc (active_video_frame_rate (), film()->video_frame_rate ());
396         if (video) {
397                 return DCPTime::from_frames (llrint (video->length_after_3d_combine() * frc.factor()), film()->video_frame_rate());
398         }
399
400         DCPOMATIC_ASSERT (audio);
401
402         DCPTime longest;
403         BOOST_FOREACH (AudioStreamPtr i, audio->streams ()) {
404                 longest = max (longest, DCPTime::from_frames (llrint (i->length() / frc.speed_up), i->frame_rate()));
405         }
406
407         return longest;
408 }
409
410 void
411 FFmpegContent::set_filters (vector<Filter const *> const & filters)
412 {
413         {
414                 boost::mutex::scoped_lock lm (_mutex);
415                 _filters = filters;
416         }
417
418         signal_changed (FFmpegContentProperty::FILTERS);
419 }
420
421 string
422 FFmpegContent::identifier () const
423 {
424         string s = Content::identifier();
425
426         if (video) {
427                 s += "_" + video->identifier();
428         }
429
430         if (only_caption() && only_caption()->use() && only_caption()->burn()) {
431                 s += "_" + only_caption()->identifier();
432         }
433
434         boost::mutex::scoped_lock lm (_mutex);
435
436         if (_subtitle_stream) {
437                 s += "_" + _subtitle_stream->identifier ();
438         }
439
440         for (vector<Filter const *>::const_iterator i = _filters.begin(); i != _filters.end(); ++i) {
441                 s += "_" + (*i)->id ();
442         }
443
444         return s;
445 }
446
447 void
448 FFmpegContent::set_default_colour_conversion ()
449 {
450         DCPOMATIC_ASSERT (video);
451
452         dcp::Size const s = video->size ();
453
454         boost::mutex::scoped_lock lm (_mutex);
455
456         switch (_colorspace.get_value_or(AVCOL_SPC_UNSPECIFIED)) {
457         case AVCOL_SPC_RGB:
458                 video->set_colour_conversion (PresetColourConversion::from_id ("srgb").conversion);
459                 break;
460         case AVCOL_SPC_BT709:
461                 video->set_colour_conversion (PresetColourConversion::from_id ("rec709").conversion);
462                 break;
463         case AVCOL_SPC_BT470BG:
464         case AVCOL_SPC_SMPTE170M:
465         case AVCOL_SPC_SMPTE240M:
466                 video->set_colour_conversion (PresetColourConversion::from_id ("rec601").conversion);
467                 break;
468         case AVCOL_SPC_BT2020_CL:
469         case AVCOL_SPC_BT2020_NCL:
470                 video->set_colour_conversion (PresetColourConversion::from_id ("rec2020").conversion);
471                 break;
472         default:
473                 if (s.width < 1080) {
474                         video->set_colour_conversion (PresetColourConversion::from_id ("rec601").conversion);
475                 } else {
476                         video->set_colour_conversion (PresetColourConversion::from_id ("rec709").conversion);
477                 }
478                 break;
479         }
480 }
481
482 void
483 FFmpegContent::add_properties (list<UserProperty>& p) const
484 {
485         Content::add_properties (p);
486
487         if (video) {
488                 video->add_properties (p);
489
490                 if (_bits_per_pixel) {
491                         int const sub = 219 * pow (2, _bits_per_pixel.get() - 8);
492                         int const total = pow (2, _bits_per_pixel.get());
493
494                         switch (_color_range.get_value_or(AVCOL_RANGE_UNSPECIFIED)) {
495                         case AVCOL_RANGE_UNSPECIFIED:
496                                 /// TRANSLATORS: this means that the range of pixel values used in this
497                                 /// file is unknown (not specified in the file).
498                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), _("Unspecified")));
499                                 break;
500                         case AVCOL_RANGE_MPEG:
501                                 /// TRANSLATORS: this means that the range of pixel values used in this
502                                 /// file is limited, so that not all possible values are valid.
503                                 p.push_back (
504                                         UserProperty (
505                                                 UserProperty::VIDEO, _("Colour range"), String::compose (_("Limited (%1-%2)"), (total - sub) / 2, (total + sub) / 2)
506                                                 )
507                                         );
508                                 break;
509                         case AVCOL_RANGE_JPEG:
510                                 /// TRANSLATORS: this means that the range of pixel values used in this
511                                 /// file is full, so that all possible pixel values are valid.
512                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), String::compose (_("Full (0-%1)"), total)));
513                                 break;
514                         default:
515                                 DCPOMATIC_ASSERT (false);
516                         }
517                 } else {
518                         switch (_color_range.get_value_or(AVCOL_RANGE_UNSPECIFIED)) {
519                         case AVCOL_RANGE_UNSPECIFIED:
520                                 /// TRANSLATORS: this means that the range of pixel values used in this
521                                 /// file is unknown (not specified in the file).
522                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), _("Unspecified")));
523                                 break;
524                         case AVCOL_RANGE_MPEG:
525                                 /// TRANSLATORS: this means that the range of pixel values used in this
526                                 /// file is limited, so that not all possible values are valid.
527                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), _("Limited")));
528                                 break;
529                         case AVCOL_RANGE_JPEG:
530                                 /// TRANSLATORS: this means that the range of pixel values used in this
531                                 /// file is full, so that all possible pixel values are valid.
532                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), _("Full")));
533                                 break;
534                         default:
535                                 DCPOMATIC_ASSERT (false);
536                         }
537                 }
538
539                 char const * primaries[] = {
540                         _("Unspecified"),
541                         _("BT709"),
542                         _("Unspecified"),
543                         _("Unspecified"),
544                         _("BT470M"),
545                         _("BT470BG"),
546                         _("SMPTE 170M (BT601)"),
547                         _("SMPTE 240M"),
548                         _("Film"),
549                         _("BT2020"),
550                         _("SMPTE ST 428-1 (CIE 1931 XYZ)"),
551                         _("SMPTE ST 431-2 (2011)"),
552                         _("SMPTE ST 432-1 D65 (2010)"), // 12
553                         "", // 13
554                         "", // 14
555                         "", // 15
556                         "", // 16
557                         "", // 17
558                         "", // 18
559                         "", // 19
560                         "", // 20
561                         "", // 21
562                         _("JEDEC P22")
563                 };
564
565                 DCPOMATIC_ASSERT (AVCOL_PRI_NB <= 23);
566                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour primaries"), primaries[_color_primaries.get_value_or(AVCOL_PRI_UNSPECIFIED)]));
567
568                 char const * transfers[] = {
569                         _("Unspecified"),
570                         _("BT709"),
571                         _("Unspecified"),
572                         _("Unspecified"),
573                         _("Gamma 22 (BT470M)"),
574                         _("Gamma 28 (BT470BG)"),
575                         _("SMPTE 170M (BT601)"),
576                         _("SMPTE 240M"),
577                         _("Linear"),
578                         _("Logarithmic (100:1 range)"),
579                         _("Logarithmic (316:1 range)"),
580                         _("IEC61966-2-4"),
581                         _("BT1361 extended colour gamut"),
582                         _("IEC61966-2-1 (sRGB or sYCC)"),
583                         _("BT2020 for a 10-bit system"),
584                         _("BT2020 for a 12-bit system"),
585                         _("SMPTE ST 2084 for 10, 12, 14 and 16 bit systems"),
586                         _("SMPTE ST 428-1"),
587                         _("ARIB STD-B67 ('Hybrid log-gamma')")
588                 };
589
590                 DCPOMATIC_ASSERT (AVCOL_TRC_NB <= 19);
591                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour transfer characteristic"), transfers[_color_trc.get_value_or(AVCOL_TRC_UNSPECIFIED)]));
592
593                 char const * spaces[] = {
594                         _("RGB / sRGB (IEC61966-2-1)"),
595                         _("BT709"),
596                         _("Unspecified"),
597                         _("Unspecified"),
598                         _("FCC"),
599                         _("BT470BG (BT601-6)"),
600                         _("SMPTE 170M (BT601-6)"),
601                         _("SMPTE 240M"),
602                         _("YCOCG"),
603                         _("BT2020 non-constant luminance"),
604                         _("BT2020 constant luminance"),
605                         _("SMPTE 2085, Y'D'zD'x"),
606                         _("Chroma-derived non-constant luminance"),
607                         _("Chroma-derived constant luminance"),
608                         _("BT2100")
609                 };
610
611                 DCPOMATIC_ASSERT (AVCOL_SPC_NB == 15);
612                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colourspace"), spaces[_colorspace.get_value_or(AVCOL_SPC_UNSPECIFIED)]));
613
614                 if (_bits_per_pixel) {
615                         p.push_back (UserProperty (UserProperty::VIDEO, _("Bits per pixel"), *_bits_per_pixel));
616                 }
617         }
618
619         if (audio) {
620                 audio->add_properties (p);
621         }
622 }
623
624 /** Our subtitle streams have colour maps, which can be changed, but
625  *  they have no way of signalling that change.  As a hack, we have this
626  *  method which callers can use when they've modified one of our subtitle
627  *  streams.
628  */
629 void
630 FFmpegContent::signal_subtitle_stream_changed ()
631 {
632         signal_changed (FFmpegContentProperty::SUBTITLE_STREAM);
633 }
634
635 vector<shared_ptr<FFmpegAudioStream> >
636 FFmpegContent::ffmpeg_audio_streams () const
637 {
638         vector<shared_ptr<FFmpegAudioStream> > fa;
639
640         if (audio) {
641                 BOOST_FOREACH (AudioStreamPtr i, audio->streams()) {
642                         fa.push_back (dynamic_pointer_cast<FFmpegAudioStream> (i));
643                 }
644         }
645
646         return fa;
647 }
648
649 void
650 FFmpegContent::take_settings_from (shared_ptr<const Content> c)
651 {
652         shared_ptr<const FFmpegContent> fc = dynamic_pointer_cast<const FFmpegContent> (c);
653         if (!fc) {
654                 return;
655                 }
656
657         Content::take_settings_from (c);
658         _filters = fc->_filters;
659 }