src/lib/player.cc

   1 /*
   2     Copyright (C) 2013-2015 Carl Hetherington <cth@carlh.net>
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include "player.h"
  21 #include "film.h"
  22 #include "ffmpeg_decoder.h"
  23 #include "audio_buffers.h"
  24 #include "ffmpeg_content.h"
  25 #include "image_decoder.h"
  26 #include "image_content.h"
  27 #include "sndfile_decoder.h"
  28 #include "sndfile_content.h"
  29 #include "subtitle_content.h"
  30 #include "subrip_decoder.h"
  31 #include "subrip_content.h"
  32 #include "dcp_content.h"
  33 #include "job.h"
  34 #include "image.h"
  35 #include "raw_image_proxy.h"
  36 #include "ratio.h"
  37 #include "log.h"
  38 #include "render_subtitles.h"
  39 #include "config.h"
  40 #include "content_video.h"
  41 #include "player_video.h"
  42 #include "frame_rate_change.h"
  43 #include "dcp_content.h"
  44 #include "dcp_decoder.h"
  45 #include "dcp_subtitle_content.h"
  46 #include "dcp_subtitle_decoder.h"
  47 #include "audio_processor.h"
  48 #include "playlist.h"
  49 #include <boost/foreach.hpp>
  50 #include <stdint.h>
  51 #include <algorithm>
  52
  53 #include "i18n.h"
  54
  55 #define LOG_GENERAL(...) _film->log()->log (String::compose (__VA_ARGS__), Log::TYPE_GENERAL);
  56
  57 using std::list;
  58 using std::cout;
  59 using std::min;
  60 using std::max;
  61 using std::min;
  62 using std::vector;
  63 using std::pair;
  64 using std::map;
  65 using std::make_pair;
  66 using std::copy;
  67 using boost::shared_ptr;
  68 using boost::weak_ptr;
  69 using boost::dynamic_pointer_cast;
  70 using boost::optional;
  71
  72 Player::Player (shared_ptr<const Film> film, shared_ptr<const Playlist> playlist)
  73         : _film (film)
  74         , _playlist (playlist)
  75         , _have_valid_pieces (false)
  76         , _ignore_video (false)
  77         , _always_burn_subtitles (false)
  78 {
  79         _film_changed_connection = _film->Changed.connect (bind (&Player::film_changed, this, _1));
  80         _playlist_changed_connection = _playlist->Changed.connect (bind (&Player::playlist_changed, this));
  81         _playlist_content_changed_connection = _playlist->ContentChanged.connect (bind (&Player::playlist_content_changed, this, _1, _2, _3));
  82         set_video_container_size (_film->frame_size ());
  83
  84         film_changed (Film::AUDIO_PROCESSOR);
  85 }
  86
  87 void
  88 Player::setup_pieces ()
  89 {
  90         list<shared_ptr<Piece> > old_pieces = _pieces;
  91         _pieces.clear ();
  92
  93         BOOST_FOREACH (shared_ptr<Content> i, _playlist->content ()) {
  94
  95                 if (!i->paths_valid ()) {
  96                         continue;
  97                 }
  98
  99                 shared_ptr<Decoder> decoder;
 100                 optional<FrameRateChange> frc;
 101
 102                 /* Work out a FrameRateChange for the best overlap video for this content, in case we need it below */
 103                 DCPTime best_overlap_t;
 104                 shared_ptr<VideoContent> best_overlap;
 105                 BOOST_FOREACH (shared_ptr<Content> j, _playlist->content ()) {
 106                         shared_ptr<VideoContent> vc = dynamic_pointer_cast<VideoContent> (j);
 107                         if (!vc) {
 108                                 continue;
 109                         }
 110
 111                         DCPTime const overlap = max (vc->position(), i->position()) - min (vc->end(), i->end());
 112                         if (overlap > best_overlap_t) {
 113                                 best_overlap = vc;
 114                                 best_overlap_t = overlap;
 115                         }
 116                 }
 117
 118                 optional<FrameRateChange> best_overlap_frc;
 119                 if (best_overlap) {
 120                         best_overlap_frc = FrameRateChange (best_overlap->video_frame_rate(), _film->video_frame_rate ());
 121                 } else {
 122                         /* No video overlap; e.g. if the DCP is just audio */
 123                         best_overlap_frc = FrameRateChange (_film->video_frame_rate(), _film->video_frame_rate ());
 124                 }
 125
 126                 /* FFmpeg */
 127                 shared_ptr<const FFmpegContent> fc = dynamic_pointer_cast<const FFmpegContent> (i);
 128                 if (fc) {
 129                         decoder.reset (new FFmpegDecoder (fc, _film->log()));
 130                         frc = FrameRateChange (fc->video_frame_rate(), _film->video_frame_rate());
 131                 }
 132
 133                 shared_ptr<const DCPContent> dc = dynamic_pointer_cast<const DCPContent> (i);
 134                 if (dc) {
 135                         decoder.reset (new DCPDecoder (dc));
 136                         frc = FrameRateChange (dc->video_frame_rate(), _film->video_frame_rate());
 137                 }
 138
 139                 /* ImageContent */
 140                 shared_ptr<const ImageContent> ic = dynamic_pointer_cast<const ImageContent> (i);
 141                 if (ic) {
 142                         /* See if we can re-use an old ImageDecoder */
 143                         for (list<shared_ptr<Piece> >::const_iterator j = old_pieces.begin(); j != old_pieces.end(); ++j) {
 144                                 shared_ptr<ImageDecoder> imd = dynamic_pointer_cast<ImageDecoder> ((*j)->decoder);
 145                                 if (imd && imd->content() == ic) {
 146                                         decoder = imd;
 147                                 }
 148                         }
 149
 150                         if (!decoder) {
 151                                 decoder.reset (new ImageDecoder (ic));
 152                         }
 153
 154                         frc = FrameRateChange (ic->video_frame_rate(), _film->video_frame_rate());
 155                 }
 156
 157                 /* SndfileContent */
 158                 shared_ptr<const SndfileContent> sc = dynamic_pointer_cast<const SndfileContent> (i);
 159                 if (sc) {
 160                         decoder.reset (new SndfileDecoder (sc));
 161                         frc = best_overlap_frc;
 162                 }
 163
 164                 /* SubRipContent */
 165                 shared_ptr<const SubRipContent> rc = dynamic_pointer_cast<const SubRipContent> (i);
 166                 if (rc) {
 167                         decoder.reset (new SubRipDecoder (rc));
 168                         frc = best_overlap_frc;
 169                 }
 170
 171                 /* DCPSubtitleContent */
 172                 shared_ptr<const DCPSubtitleContent> dsc = dynamic_pointer_cast<const DCPSubtitleContent> (i);
 173                 if (dsc) {
 174                         decoder.reset (new DCPSubtitleDecoder (dsc));
 175                         frc = best_overlap_frc;
 176                 }
 177
 178                 shared_ptr<VideoDecoder> vd = dynamic_pointer_cast<VideoDecoder> (decoder);
 179                 if (vd && _ignore_video) {
 180                         vd->set_ignore_video ();
 181                 }
 182
 183                 _pieces.push_back (shared_ptr<Piece> (new Piece (i, decoder, frc.get ())));
 184         }
 185
 186         _have_valid_pieces = true;
 187 }
 188
 189 void
 190 Player::playlist_content_changed (weak_ptr<Content> w, int property, bool frequent)
 191 {
 192         shared_ptr<Content> c = w.lock ();
 193         if (!c) {
 194                 return;
 195         }
 196
 197         if (
 198                 property == ContentProperty::POSITION ||
 199                 property == ContentProperty::LENGTH ||
 200                 property == ContentProperty::TRIM_START ||
 201                 property == ContentProperty::TRIM_END ||
 202                 property == ContentProperty::PATH ||
 203                 property == VideoContentProperty::VIDEO_FRAME_TYPE ||
 204                 property == DCPContentProperty::CAN_BE_PLAYED
 205                 ) {
 206
 207                 _have_valid_pieces = false;
 208                 Changed (frequent);
 209
 210         } else if (
 211                 property == SubtitleContentProperty::USE_SUBTITLES ||
 212                 property == SubtitleContentProperty::SUBTITLE_X_OFFSET ||
 213                 property == SubtitleContentProperty::SUBTITLE_Y_OFFSET ||
 214                 property == SubtitleContentProperty::SUBTITLE_X_SCALE ||
 215                 property == SubtitleContentProperty::SUBTITLE_Y_SCALE ||
 216                 property == VideoContentProperty::VIDEO_CROP ||
 217                 property == VideoContentProperty::VIDEO_SCALE ||
 218                 property == VideoContentProperty::VIDEO_FRAME_RATE ||
 219                 property == VideoContentProperty::VIDEO_FADE_IN ||
 220                 property == VideoContentProperty::VIDEO_FADE_OUT
 221                 ) {
 222
 223                 Changed (frequent);
 224         }
 225 }
 226
 227 void
 228 Player::set_video_container_size (dcp::Size s)
 229 {
 230         _video_container_size = s;
 231
 232         _black_image.reset (new Image (PIX_FMT_RGB24, _video_container_size, true));
 233         _black_image->make_black ();
 234 }
 235
 236 void
 237 Player::playlist_changed ()
 238 {
 239         _have_valid_pieces = false;
 240         Changed (false);
 241 }
 242
 243 void
 244 Player::film_changed (Film::Property p)
 245 {
 246         /* Here we should notice Film properties that affect our output, and
 247            alert listeners that our output now would be different to how it was
 248            last time we were run.
 249         */
 250
 251         if (p == Film::CONTAINER || p == Film::VIDEO_FRAME_RATE) {
 252                 Changed (false);
 253         } else if (p == Film::AUDIO_PROCESSOR) {
 254                 if (_film->audio_processor ()) {
 255                         _audio_processor = _film->audio_processor()->clone (_film->audio_frame_rate ());
 256                 }
 257         }
 258 }
 259
 260 list<PositionImage>
 261 Player::transform_image_subtitles (list<ImageSubtitle> subs) const
 262 {
 263         list<PositionImage> all;
 264
 265         for (list<ImageSubtitle>::const_iterator i = subs.begin(); i != subs.end(); ++i) {
 266                 if (!i->image) {
 267                         continue;
 268                 }
 269
 270                 /* We will scale the subtitle up to fit _video_container_size */
 271                 dcp::Size scaled_size (i->rectangle.width * _video_container_size.width, i->rectangle.height * _video_container_size.height);
 272
 273                 /* Then we need a corrective translation, consisting of two parts:
 274                  *
 275                  * 1.  that which is the result of the scaling of the subtitle by _video_container_size; this will be
 276                  *     rect.x * _video_container_size.width and rect.y * _video_container_size.height.
 277                  *
 278                  * 2.  that to shift the origin of the scale by subtitle_scale to the centre of the subtitle; this will be
 279                  *     (width_before_subtitle_scale * (1 - subtitle_x_scale) / 2) and
 280                  *     (height_before_subtitle_scale * (1 - subtitle_y_scale) / 2).
 281                  *
 282                  * Combining these two translations gives these expressions.
 283                  */
 284
 285                 all.push_back (
 286                         PositionImage (
 287                                 i->image->scale (
 288                                         scaled_size,
 289                                         dcp::YUV_TO_RGB_REC601,
 290                                         i->image->pixel_format (),
 291                                         true
 292                                         ),
 293                                 Position<int> (
 294                                         rint (_video_container_size.width * i->rectangle.x),
 295                                         rint (_video_container_size.height * i->rectangle.y)
 296                                         )
 297                                 )
 298                         );
 299         }
 300
 301         return all;
 302 }
 303
 304 shared_ptr<PlayerVideo>
 305 Player::black_player_video_frame (DCPTime time) const
 306 {
 307         return shared_ptr<PlayerVideo> (
 308                 new PlayerVideo (
 309                         shared_ptr<const ImageProxy> (new RawImageProxy (_black_image)),
 310                         time,
 311                         Crop (),
 312                         optional<double> (),
 313                         _video_container_size,
 314                         _video_container_size,
 315                         EYES_BOTH,
 316                         PART_WHOLE,
 317                         PresetColourConversion::all().front().conversion
 318                 )
 319         );
 320 }
 321
 322 /** @return All PlayerVideos at the given time (there may be two frames for 3D) */
 323 list<shared_ptr<PlayerVideo> >
 324 Player::get_video (DCPTime time, bool accurate)
 325 {
 326         if (!_have_valid_pieces) {
 327                 setup_pieces ();
 328         }
 329
 330         /* Find subtitles for possible burn-in */
 331
 332         PlayerSubtitles ps = get_subtitles (time, DCPTime::from_frames (1, _film->video_frame_rate ()), false, true);
 333
 334         list<PositionImage> sub_images;
 335
 336         /* Image subtitles */
 337         list<PositionImage> c = transform_image_subtitles (ps.image);
 338         copy (c.begin(), c.end(), back_inserter (sub_images));
 339
 340         /* Text subtitles (rendered to an image) */
 341         if (!ps.text.empty ()) {
 342                 list<PositionImage> s = render_subtitles (ps.text, _video_container_size);
 343                 copy (s.begin (), s.end (), back_inserter (sub_images));
 344         }
 345
 346         optional<PositionImage> subtitles;
 347         if (!sub_images.empty ()) {
 348                 subtitles = merge (sub_images);
 349         }
 350
 351         /* Find video */
 352
 353         list<shared_ptr<Piece> > ov = overlaps<VideoContent> (
 354                 time,
 355                 time + DCPTime::from_frames (1, _film->video_frame_rate ()) - DCPTime::delta()
 356                 );
 357
 358         list<shared_ptr<PlayerVideo> > pvf;
 359
 360         if (ov.empty ()) {
 361                 /* No video content at this time */
 362                 pvf.push_back (black_player_video_frame (time));
 363         } else {
 364                 /* Decide which pieces of content to use */
 365                 list<shared_ptr<Piece> > ov_to_use;
 366
 367                 /* Always use the last one */
 368                 list<shared_ptr<Piece> >::reverse_iterator i = ov.rbegin ();
 369                 ov_to_use.push_back (*i);
 370                 VideoFrameType const first_type = dynamic_pointer_cast<VideoContent> ((*i)->content)->video_frame_type ();
 371
 372                 ++i;
 373                 if (i != ov.rend ()) {
 374                         shared_ptr<VideoContent> vc = dynamic_pointer_cast<VideoContent> ((*i)->content);
 375                         /* Use the second to last if it's the other part of a 3D content pair */
 376                         if (
 377                                 (first_type == VIDEO_FRAME_TYPE_3D_LEFT && vc->video_frame_type() == VIDEO_FRAME_TYPE_3D_RIGHT) ||
 378                                 (first_type == VIDEO_FRAME_TYPE_3D_RIGHT && vc->video_frame_type() == VIDEO_FRAME_TYPE_3D_LEFT)
 379                                 ) {
 380                                 /* Other part of a pair of 3D content */
 381                                 ov_to_use.push_back (*i);
 382                         }
 383                 }
 384
 385                 BOOST_FOREACH (shared_ptr<Piece> piece, ov_to_use) {
 386                         shared_ptr<VideoDecoder> decoder = dynamic_pointer_cast<VideoDecoder> (piece->decoder);
 387                         DCPOMATIC_ASSERT (decoder);
 388                         shared_ptr<VideoContent> video_content = dynamic_pointer_cast<VideoContent> (piece->content);
 389                         DCPOMATIC_ASSERT (video_content);
 390
 391                         list<ContentVideo> content_video = decoder->get_video (dcp_to_content_video (piece, time), accurate);
 392                         if (content_video.empty ()) {
 393                                 pvf.push_back (black_player_video_frame (time));
 394                         } else {
 395                                 dcp::Size image_size = video_content->scale().size (video_content, _video_container_size, _film->frame_size ());
 396
 397                                 for (list<ContentVideo>::const_iterator i = content_video.begin(); i != content_video.end(); ++i) {
 398                                         pvf.push_back (
 399                                                 shared_ptr<PlayerVideo> (
 400                                                         new PlayerVideo (
 401                                                                 i->image,
 402                                                                 content_video_to_dcp (piece, i->frame),
 403                                                                 video_content->crop (),
 404                                                                 video_content->fade (i->frame),
 405                                                                 image_size,
 406                                                                 _video_container_size,
 407                                                                 i->eyes,
 408                                                                 i->part,
 409                                                                 video_content->colour_conversion ()
 410                                                                 )
 411                                                         )
 412                                                 );
 413                                 }
 414                         }
 415                 }
 416         }
 417
 418         if (subtitles) {
 419                 BOOST_FOREACH (shared_ptr<PlayerVideo> p, pvf) {
 420                         p->set_subtitle (subtitles.get ());
 421                 }
 422         }
 423
 424         return pvf;
 425 }
 426
 427 shared_ptr<AudioBuffers>
 428 Player::get_audio (DCPTime time, DCPTime length, bool accurate)
 429 {
 430         if (!_have_valid_pieces) {
 431                 setup_pieces ();
 432         }
 433
 434         Frame const length_frames = length.frames_round (_film->audio_frame_rate ());
 435
 436         shared_ptr<AudioBuffers> audio (new AudioBuffers (_film->audio_channels(), length_frames));
 437         audio->make_silent ();
 438
 439         list<shared_ptr<Piece> > ov = overlaps<AudioContent> (time, time + length);
 440         if (ov.empty ()) {
 441                 return audio;
 442         }
 443
 444         for (list<shared_ptr<Piece> >::iterator i = ov.begin(); i != ov.end(); ++i) {
 445
 446                 shared_ptr<AudioContent> content = dynamic_pointer_cast<AudioContent> ((*i)->content);
 447                 DCPOMATIC_ASSERT (content);
 448                 shared_ptr<AudioDecoder> decoder = dynamic_pointer_cast<AudioDecoder> ((*i)->decoder);
 449                 DCPOMATIC_ASSERT (decoder);
 450
 451                 /* The time that we should request from the content */
 452                 DCPTime request = time - DCPTime::from_seconds (content->audio_delay() / 1000.0);
 453                 Frame request_frames = length_frames;
 454                 DCPTime offset;
 455                 if (request < DCPTime ()) {
 456                         /* We went off the start of the content, so we will need to offset
 457                            the stuff we get back.
 458                         */
 459                         offset = -request;
 460                         request_frames += request.frames_round (_film->audio_frame_rate ());
 461                         if (request_frames < 0) {
 462                                 request_frames = 0;
 463                         }
 464                         request = DCPTime ();
 465                 }
 466
 467                 Frame const content_frame = dcp_to_resampled_audio (*i, request);
 468
 469                 BOOST_FOREACH (AudioStreamPtr j, content->audio_streams ()) {
 470
 471                         if (j->channels() == 0) {
 472                                 /* Some content (e.g. DCPs) can have streams with no channels */
 473                                 continue;
 474                         }
 475
 476                         /* Audio from this piece's decoder stream (which might be more or less than what we asked for) */
 477                         ContentAudio all = decoder->get_audio (j, content_frame, request_frames, accurate);
 478
 479                         /* Gain */
 480                         if (content->audio_gain() != 0) {
 481                                 shared_ptr<AudioBuffers> gain (new AudioBuffers (all.audio));
 482                                 gain->apply_gain (content->audio_gain ());
 483                                 all.audio = gain;
 484                         }
 485
 486                         /* Remap channels */
 487                         shared_ptr<AudioBuffers> dcp_mapped (new AudioBuffers (_film->audio_channels(), all.audio->frames()));
 488                         dcp_mapped->make_silent ();
 489                         AudioMapping map = j->mapping ();
 490                         for (int i = 0; i < map.input_channels(); ++i) {
 491                                 for (int j = 0; j < _film->audio_channels(); ++j) {
 492                                         if (map.get (i, j) > 0) {
 493                                                 dcp_mapped->accumulate_channel (
 494                                                         all.audio.get(),
 495                                                         i,
 496                                                         j,
 497                                                         map.get (i, j)
 498                                                         );
 499                                         }
 500                                 }
 501                         }
 502
 503                         if (_audio_processor) {
 504                                 dcp_mapped = _audio_processor->run (dcp_mapped);
 505                         }
 506
 507                         all.audio = dcp_mapped;
 508
 509                         audio->accumulate_frames (
 510                                 all.audio.get(),
 511                                 content_frame - all.frame,
 512                                 offset.frames_round (_film->audio_frame_rate()),
 513                                 min (Frame (all.audio->frames()), request_frames)
 514                                 );
 515                 }
 516         }
 517
 518         return audio;
 519 }
 520
 521 Frame
 522 Player::dcp_to_content_video (shared_ptr<const Piece> piece, DCPTime t) const
 523 {
 524         shared_ptr<const VideoContent> vc = dynamic_pointer_cast<const VideoContent> (piece->content);
 525         DCPTime s = t - piece->content->position ();
 526         s = min (piece->content->length_after_trim(), s);
 527         /* We're returning a frame index here so we need to floor() the conversion since we want to know the frame
 528            that contains t, I think
 529         */
 530         return max (ContentTime (), ContentTime (s, piece->frc) + piece->content->trim_start ()).frames_floor (vc->video_frame_rate ());
 531 }
 532
 533 DCPTime
 534 Player::content_video_to_dcp (shared_ptr<const Piece> piece, Frame f) const
 535 {
 536         shared_ptr<const VideoContent> vc = dynamic_pointer_cast<const VideoContent> (piece->content);
 537         ContentTime const c = ContentTime::from_frames (f, vc->video_frame_rate ()) - piece->content->trim_start ();
 538         return max (DCPTime (), DCPTime (c, piece->frc) + piece->content->position ());
 539 }
 540
 541 Frame
 542 Player::dcp_to_resampled_audio (shared_ptr<const Piece> piece, DCPTime t) const
 543 {
 544         DCPTime s = t - piece->content->position ();
 545         s = min (piece->content->length_after_trim(), s);
 546         /* See notes in dcp_to_content_video */
 547         return max (DCPTime (), DCPTime (piece->content->trim_start (), piece->frc) + s).frames_floor (_film->audio_frame_rate ());
 548 }
 549
 550 ContentTime
 551 Player::dcp_to_content_subtitle (shared_ptr<const Piece> piece, DCPTime t) const
 552 {
 553         DCPTime s = t - piece->content->position ();
 554         s = min (piece->content->length_after_trim(), s);
 555         return max (ContentTime (), ContentTime (s, piece->frc) + piece->content->trim_start());
 556 }
 557
 558 /** @param burnt true to return only subtitles to be burnt, false to return only
 559  *  subtitles that should not be burnt.  This parameter will be ignored if
 560  *  _always_burn_subtitles is true; in this case, all subtitles will be returned.
 561  */
 562 PlayerSubtitles
 563 Player::get_subtitles (DCPTime time, DCPTime length, bool starting, bool burnt)
 564 {
 565         list<shared_ptr<Piece> > subs = overlaps<SubtitleContent> (time, time + length);
 566
 567         PlayerSubtitles ps (time, length);
 568
 569         for (list<shared_ptr<Piece> >::const_iterator j = subs.begin(); j != subs.end(); ++j) {
 570                 shared_ptr<SubtitleContent> subtitle_content = dynamic_pointer_cast<SubtitleContent> ((*j)->content);
 571                 if (!subtitle_content->use_subtitles () || (!_always_burn_subtitles && (burnt != subtitle_content->burn_subtitles ()))) {
 572                         continue;
 573                 }
 574
 575                 shared_ptr<SubtitleDecoder> subtitle_decoder = dynamic_pointer_cast<SubtitleDecoder> ((*j)->decoder);
 576                 ContentTime const from = dcp_to_content_subtitle (*j, time);
 577                 /* XXX: this video_frame_rate() should be the rate that the subtitle content has been prepared for */
 578                 ContentTime const to = from + ContentTime::from_frames (1, _film->video_frame_rate ());
 579
 580                 list<ContentImageSubtitle> image = subtitle_decoder->get_image_subtitles (ContentTimePeriod (from, to), starting);
 581                 for (list<ContentImageSubtitle>::iterator i = image.begin(); i != image.end(); ++i) {
 582
 583                         /* Apply content's subtitle offsets */
 584                         i->sub.rectangle.x += subtitle_content->subtitle_x_offset ();
 585                         i->sub.rectangle.y += subtitle_content->subtitle_y_offset ();
 586
 587                         /* Apply content's subtitle scale */
 588                         i->sub.rectangle.width *= subtitle_content->subtitle_x_scale ();
 589                         i->sub.rectangle.height *= subtitle_content->subtitle_y_scale ();
 590
 591                         /* Apply a corrective translation to keep the subtitle centred after that scale */
 592                         i->sub.rectangle.x -= i->sub.rectangle.width * (subtitle_content->subtitle_x_scale() - 1);
 593                         i->sub.rectangle.y -= i->sub.rectangle.height * (subtitle_content->subtitle_y_scale() - 1);
 594
 595                         ps.image.push_back (i->sub);
 596                 }
 597
 598                 list<ContentTextSubtitle> text = subtitle_decoder->get_text_subtitles (ContentTimePeriod (from, to), starting);
 599                 BOOST_FOREACH (ContentTextSubtitle& ts, text) {
 600                         BOOST_FOREACH (dcp::SubtitleString& s, ts.subs) {
 601                                 s.set_h_position (s.h_position() + subtitle_content->subtitle_x_offset ());
 602                                 s.set_v_position (s.v_position() + subtitle_content->subtitle_y_offset ());
 603                                 float const xs = subtitle_content->subtitle_x_scale();
 604                                 float const ys = subtitle_content->subtitle_y_scale();
 605                                 float const average = s.size() * (xs + ys) / 2;
 606                                 s.set_size (average);
 607                                 if (fabs (1.0 - xs / ys) > dcp::ASPECT_ADJUST_EPSILON) {
 608                                         s.set_aspect_adjust (xs / ys);
 609                                 }
 610                                 ps.text.push_back (s);
 611                         }
 612                 }
 613         }
 614
 615         return ps;
 616 }
 617
 618 list<shared_ptr<Font> >
 619 Player::get_subtitle_fonts ()
 620 {
 621         if (!_have_valid_pieces) {
 622                 setup_pieces ();
 623         }
 624
 625         list<shared_ptr<Font> > fonts;
 626         BOOST_FOREACH (shared_ptr<Piece>& p, _pieces) {
 627                 shared_ptr<SubtitleContent> sc = dynamic_pointer_cast<SubtitleContent> (p->content);
 628                 if (sc) {
 629                         /* XXX: things may go wrong if there are duplicate font IDs
 630                            with different font files.
 631                         */
 632                         list<shared_ptr<Font> > f = sc->fonts ();
 633                         copy (f.begin(), f.end(), back_inserter (fonts));
 634                 }
 635         }
 636
 637         return fonts;
 638 }
 639
 640 /** Set this player never to produce any video data */
 641 void
 642 Player::set_ignore_video ()
 643 {
 644         _ignore_video = true;
 645 }
 646
 647 /** Set whether or not this player should always burn text subtitles into the image,
 648  *  regardless of the content settings.
 649  *  @param burn true to always burn subtitles, false to obey content settings.
 650  */
 651 void
 652 Player::set_always_burn_subtitles (bool burn)
 653 {
 654         _always_burn_subtitles = burn;
 655 }