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 "subtitle_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         subtitle = SubtitleContent::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_subtitle = 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_subtitle = static_cast<bool> ((*i)->subtitle);
 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_subtitle != static_cast<bool> ((*i)->subtitle)) {
 154                         throw JoinError (_("Content to be joined must all have or not have subtitles"));
 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_subtitle) {
 166                 subtitle.reset (new SubtitleContent (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->subtitle && fc->subtitle->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 (subtitle) {
 213                 subtitle->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
 279                 if (!examiner->audio_streams().empty ()) {
 280                         audio.reset (new AudioContent (this));
 281
 282                         BOOST_FOREACH (shared_ptr<FFmpegAudioStream> i, examiner->audio_streams ()) {
 283                                 audio->add_stream (i);
 284                         }
 285
 286                         AudioStreamPtr as = audio->streams().front();
 287                         AudioMapping m = as->mapping ();
 288                         film()->make_audio_mapping_default (m, first_path);
 289                         as->set_mapping (m);
 290                 }
 291
 292                 _subtitle_streams = examiner->subtitle_streams ();
 293                 if (!_subtitle_streams.empty ()) {
 294                         subtitle.reset (new SubtitleContent (this));
 295                         _subtitle_stream = _subtitle_streams.front ();
 296                 }
 297
 298         }
 299
 300         if (examiner->has_video ()) {
 301                 set_default_colour_conversion ();
 302         }
 303
 304         signal_changed (FFmpegContentProperty::SUBTITLE_STREAMS);
 305         signal_changed (FFmpegContentProperty::SUBTITLE_STREAM);
 306 }
 307
 308 string
 309 FFmpegContent::summary () const
 310 {
 311         if (video && audio) {
 312                 return String::compose (_("%1 [movie]"), path_summary ());
 313         } else if (video) {
 314                 return String::compose (_("%1 [video]"), path_summary ());
 315         } else if (audio) {
 316                 return String::compose (_("%1 [audio]"), path_summary ());
 317         }
 318
 319         return path_summary ();
 320 }
 321
 322 string
 323 FFmpegContent::technical_summary () const
 324 {
 325         string as = "";
 326         BOOST_FOREACH (shared_ptr<FFmpegAudioStream> i, ffmpeg_audio_streams ()) {
 327                 as += i->technical_summary () + " " ;
 328         }
 329
 330         if (as.empty ()) {
 331                 as = "none";
 332         }
 333
 334         string ss = "none";
 335         if (_subtitle_stream) {
 336                 ss = _subtitle_stream->technical_summary ();
 337         }
 338
 339         string filt = Filter::ffmpeg_string (_filters);
 340
 341         string s = Content::technical_summary ();
 342
 343         if (video) {
 344                 s += " - " + video->technical_summary ();
 345         }
 346
 347         if (audio) {
 348                 s += " - " + audio->technical_summary ();
 349         }
 350
 351         return s + String::compose (
 352                 "ffmpeg: audio %1 subtitle %2 filters %3", as, ss, filt
 353                 );
 354 }
 355
 356 void
 357 FFmpegContent::set_subtitle_stream (shared_ptr<FFmpegSubtitleStream> s)
 358 {
 359         {
 360                 boost::mutex::scoped_lock lm (_mutex);
 361                 _subtitle_stream = s;
 362         }
 363
 364         signal_changed (FFmpegContentProperty::SUBTITLE_STREAM);
 365 }
 366
 367 bool
 368 operator== (FFmpegStream const & a, FFmpegStream const & b)
 369 {
 370         return a._id == b._id;
 371 }
 372
 373 bool
 374 operator!= (FFmpegStream const & a, FFmpegStream const & b)
 375 {
 376         return a._id != b._id;
 377 }
 378
 379 DCPTime
 380 FFmpegContent::full_length () const
 381 {
 382         FrameRateChange const frc (active_video_frame_rate (), film()->video_frame_rate ());
 383         if (video) {
 384                 return DCPTime::from_frames (llrint (video->length_after_3d_combine() * frc.factor()), film()->video_frame_rate());
 385         }
 386
 387         DCPOMATIC_ASSERT (audio);
 388
 389         DCPTime longest;
 390         BOOST_FOREACH (AudioStreamPtr i, audio->streams ()) {
 391                 longest = max (longest, DCPTime::from_frames (llrint (i->length() / frc.speed_up), i->frame_rate()));
 392         }
 393
 394         return longest;
 395 }
 396
 397 void
 398 FFmpegContent::set_filters (vector<Filter const *> const & filters)
 399 {
 400         {
 401                 boost::mutex::scoped_lock lm (_mutex);
 402                 _filters = filters;
 403         }
 404
 405         signal_changed (FFmpegContentProperty::FILTERS);
 406 }
 407
 408 string
 409 FFmpegContent::identifier () const
 410 {
 411         string s = Content::identifier();
 412
 413         if (video) {
 414                 s += "_" + video->identifier();
 415         }
 416
 417         if (subtitle && subtitle->use() && subtitle->burn()) {
 418                 s += "_" + subtitle->identifier();
 419         }
 420
 421         boost::mutex::scoped_lock lm (_mutex);
 422
 423         if (_subtitle_stream) {
 424                 s += "_" + _subtitle_stream->identifier ();
 425         }
 426
 427         for (vector<Filter const *>::const_iterator i = _filters.begin(); i != _filters.end(); ++i) {
 428                 s += "_" + (*i)->id ();
 429         }
 430
 431         return s;
 432 }
 433
 434 void
 435 FFmpegContent::set_default_colour_conversion ()
 436 {
 437         DCPOMATIC_ASSERT (video);
 438
 439         dcp::Size const s = video->size ();
 440
 441         boost::mutex::scoped_lock lm (_mutex);
 442
 443         switch (_colorspace.get_value_or(AVCOL_SPC_UNSPECIFIED)) {
 444         case AVCOL_SPC_RGB:
 445                 video->set_colour_conversion (PresetColourConversion::from_id ("srgb").conversion);
 446                 break;
 447         case AVCOL_SPC_BT709:
 448                 video->set_colour_conversion (PresetColourConversion::from_id ("rec709").conversion);
 449                 break;
 450         case AVCOL_SPC_BT470BG:
 451         case AVCOL_SPC_SMPTE170M:
 452         case AVCOL_SPC_SMPTE240M:
 453                 video->set_colour_conversion (PresetColourConversion::from_id ("rec601").conversion);
 454                 break;
 455         case AVCOL_SPC_BT2020_CL:
 456         case AVCOL_SPC_BT2020_NCL:
 457                 video->set_colour_conversion (PresetColourConversion::from_id ("rec2020").conversion);
 458                 break;
 459         default:
 460                 if (s.width < 1080) {
 461                         video->set_colour_conversion (PresetColourConversion::from_id ("rec601").conversion);
 462                 } else {
 463                         video->set_colour_conversion (PresetColourConversion::from_id ("rec709").conversion);
 464                 }
 465                 break;
 466         }
 467 }
 468
 469 void
 470 FFmpegContent::add_properties (list<UserProperty>& p) const
 471 {
 472         Content::add_properties (p);
 473
 474         if (video) {
 475                 video->add_properties (p);
 476
 477                 if (_bits_per_pixel) {
 478                         int const sub = 219 * pow (2, _bits_per_pixel.get() - 8);
 479                         int const total = pow (2, _bits_per_pixel.get());
 480
 481                         switch (_color_range.get_value_or(AVCOL_RANGE_UNSPECIFIED)) {
 482                         case AVCOL_RANGE_UNSPECIFIED:
 483                                 /// TRANSLATORS: this means that the range of pixel values used in this
 484                                 /// file is unknown (not specified in the file).
 485                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), _("Unspecified")));
 486                                 break;
 487                         case AVCOL_RANGE_MPEG:
 488                                 /// TRANSLATORS: this means that the range of pixel values used in this
 489                                 /// file is limited, so that not all possible values are valid.
 490                                 p.push_back (
 491                                         UserProperty (
 492                                                 UserProperty::VIDEO, _("Colour range"), String::compose (_("Limited (%1-%2)"), (total - sub) / 2, (total + sub) / 2)
 493                                                 )
 494                                         );
 495                                 break;
 496                         case AVCOL_RANGE_JPEG:
 497                                 /// TRANSLATORS: this means that the range of pixel values used in this
 498                                 /// file is full, so that all possible pixel values are valid.
 499                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), String::compose (_("Full (0-%1)"), total)));
 500                                 break;
 501                         default:
 502                                 DCPOMATIC_ASSERT (false);
 503                         }
 504                 } else {
 505                         switch (_color_range.get_value_or(AVCOL_RANGE_UNSPECIFIED)) {
 506                         case AVCOL_RANGE_UNSPECIFIED:
 507                                 /// TRANSLATORS: this means that the range of pixel values used in this
 508                                 /// file is unknown (not specified in the file).
 509                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), _("Unspecified")));
 510                                 break;
 511                         case AVCOL_RANGE_MPEG:
 512                                 /// TRANSLATORS: this means that the range of pixel values used in this
 513                                 /// file is limited, so that not all possible values are valid.
 514                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), _("Limited")));
 515                                 break;
 516                         case AVCOL_RANGE_JPEG:
 517                                 /// TRANSLATORS: this means that the range of pixel values used in this
 518                                 /// file is full, so that all possible pixel values are valid.
 519                                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour range"), _("Full")));
 520                                 break;
 521                         default:
 522                                 DCPOMATIC_ASSERT (false);
 523                         }
 524                 }
 525
 526                 char const * primaries[] = {
 527                         _("Unspecified"),
 528                         _("BT709"),
 529                         _("Unspecified"),
 530                         _("Unspecified"),
 531                         _("BT470M"),
 532                         _("BT470BG"),
 533                         _("SMPTE 170M (BT601)"),
 534                         _("SMPTE 240M"),
 535                         _("Film"),
 536                         _("BT2020"),
 537                         _("SMPTE ST 428-1 (CIE 1931 XYZ)"),
 538                         _("SMPTE ST 431-2 (2011)"),
 539                         _("SMPTE ST 432-1 D65 (2010)"), // 12
 540                         "", // 13
 541                         "", // 14
 542                         "", // 15
 543                         "", // 16
 544                         "", // 17
 545                         "", // 18
 546                         "", // 19
 547                         "", // 20
 548                         "", // 21
 549                         _("JEDEC P22")
 550                 };
 551
 552                 DCPOMATIC_ASSERT (AVCOL_PRI_NB <= 23);
 553                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour primaries"), primaries[_color_primaries.get_value_or(AVCOL_PRI_UNSPECIFIED)]));
 554
 555                 char const * transfers[] = {
 556                         _("Unspecified"),
 557                         _("BT709"),
 558                         _("Unspecified"),
 559                         _("Unspecified"),
 560                         _("Gamma 22 (BT470M)"),
 561                         _("Gamma 28 (BT470BG)"),
 562                         _("SMPTE 170M (BT601)"),
 563                         _("SMPTE 240M"),
 564                         _("Linear"),
 565                         _("Logarithmic (100:1 range)"),
 566                         _("Logarithmic (316:1 range)"),
 567                         _("IEC61966-2-4"),
 568                         _("BT1361 extended colour gamut"),
 569                         _("IEC61966-2-1 (sRGB or sYCC)"),
 570                         _("BT2020 for a 10-bit system"),
 571                         _("BT2020 for a 12-bit system"),
 572                         _("SMPTE ST 2084 for 10, 12, 14 and 16 bit systems"),
 573                         _("SMPTE ST 428-1"),
 574                         _("ARIB STD-B67 ('Hybrid log-gamma')")
 575                 };
 576
 577                 DCPOMATIC_ASSERT (AVCOL_TRC_NB <= 19);
 578                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colour transfer characteristic"), transfers[_color_trc.get_value_or(AVCOL_TRC_UNSPECIFIED)]));
 579
 580                 char const * spaces[] = {
 581                         _("RGB / sRGB (IEC61966-2-1)"),
 582                         _("BT709"),
 583                         _("Unspecified"),
 584                         _("Unspecified"),
 585                         _("FCC"),
 586                         _("BT470BG (BT601-6)"),
 587                         _("SMPTE 170M (BT601-6)"),
 588                         _("SMPTE 240M"),
 589                         _("YCOCG"),
 590                         _("BT2020 non-constant luminance"),
 591                         _("BT2020 constant luminance"),
 592                         _("SMPTE 2085, Y'D'zD'x"),
 593                         _("Chroma-derived non-constant luminance"),
 594                         _("Chroma-derived constant luminance"),
 595                         _("BT2100")
 596                 };
 597
 598                 DCPOMATIC_ASSERT (AVCOL_SPC_NB == 15);
 599                 p.push_back (UserProperty (UserProperty::VIDEO, _("Colourspace"), spaces[_colorspace.get_value_or(AVCOL_SPC_UNSPECIFIED)]));
 600
 601                 if (_bits_per_pixel) {
 602                         p.push_back (UserProperty (UserProperty::VIDEO, _("Bits per pixel"), *_bits_per_pixel));
 603                 }
 604         }
 605
 606         if (audio) {
 607                 audio->add_properties (p);
 608         }
 609 }
 610
 611 /** Our subtitle streams have colour maps, which can be changed, but
 612  *  they have no way of signalling that change.  As a hack, we have this
 613  *  method which callers can use when they've modified one of our subtitle
 614  *  streams.
 615  */
 616 void
 617 FFmpegContent::signal_subtitle_stream_changed ()
 618 {
 619         signal_changed (FFmpegContentProperty::SUBTITLE_STREAM);
 620 }
 621
 622 vector<shared_ptr<FFmpegAudioStream> >
 623 FFmpegContent::ffmpeg_audio_streams () const
 624 {
 625         vector<shared_ptr<FFmpegAudioStream> > fa;
 626
 627         if (audio) {
 628                 BOOST_FOREACH (AudioStreamPtr i, audio->streams()) {
 629                         fa.push_back (dynamic_pointer_cast<FFmpegAudioStream> (i));
 630                 }
 631         }
 632
 633         return fa;
 634 }
 635
 636 void
 637 FFmpegContent::take_settings_from (shared_ptr<const Content> c)
 638 {
 639         shared_ptr<const FFmpegContent> fc = dynamic_pointer_cast<const FFmpegContent> (c);
 640         if (!fc) {
 641                 return;
 642                 }
 643
 644         Content::take_settings_from (c);
 645         _filters = fc->_filters;
 646 }