src/lib/player.cc

   1 /*
   2     Copyright (C) 2013-2017 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 "player.h"
  22 #include "film.h"
  23 #include "audio_buffers.h"
  24 #include "content_audio.h"
  25 #include "dcp_content.h"
  26 #include "job.h"
  27 #include "image.h"
  28 #include "raw_image_proxy.h"
  29 #include "ratio.h"
  30 #include "log.h"
  31 #include "render_subtitles.h"
  32 #include "config.h"
  33 #include "content_video.h"
  34 #include "player_video.h"
  35 #include "frame_rate_change.h"
  36 #include "audio_processor.h"
  37 #include "playlist.h"
  38 #include "referenced_reel_asset.h"
  39 #include "decoder_factory.h"
  40 #include "decoder.h"
  41 #include "video_decoder.h"
  42 #include "audio_decoder.h"
  43 #include "subtitle_content.h"
  44 #include "subtitle_decoder.h"
  45 #include "ffmpeg_content.h"
  46 #include "audio_content.h"
  47 #include "content_subtitle.h"
  48 #include "dcp_decoder.h"
  49 #include "image_decoder.h"
  50 #include "compose.hpp"
  51 #include <dcp/reel.h>
  52 #include <dcp/reel_sound_asset.h>
  53 #include <dcp/reel_subtitle_asset.h>
  54 #include <dcp/reel_picture_asset.h>
  55 #include <boost/foreach.hpp>
  56 #include <stdint.h>
  57 #include <algorithm>
  58 #include <iostream>
  59
  60 #include "i18n.h"
  61
  62 #define LOG_GENERAL(...) _film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_GENERAL);
  63
  64 using std::list;
  65 using std::cout;
  66 using std::min;
  67 using std::max;
  68 using std::min;
  69 using std::vector;
  70 using std::pair;
  71 using std::map;
  72 using std::make_pair;
  73 using std::copy;
  74 using boost::shared_ptr;
  75 using boost::weak_ptr;
  76 using boost::dynamic_pointer_cast;
  77 using boost::optional;
  78 using boost::scoped_ptr;
  79
  80 Player::Player (shared_ptr<const Film> film, shared_ptr<const Playlist> playlist)
  81         : _film (film)
  82         , _playlist (playlist)
  83         , _have_valid_pieces (false)
  84         , _ignore_video (false)
  85         , _ignore_audio (false)
  86         , _always_burn_subtitles (false)
  87         , _fast (false)
  88         , _play_referenced (false)
  89         , _audio_merger (_film->audio_frame_rate())
  90 {
  91         _film_changed_connection = _film->Changed.connect (bind (&Player::film_changed, this, _1));
  92         _playlist_changed_connection = _playlist->Changed.connect (bind (&Player::playlist_changed, this));
  93         _playlist_content_changed_connection = _playlist->ContentChanged.connect (bind (&Player::playlist_content_changed, this, _1, _2, _3));
  94         set_video_container_size (_film->frame_size ());
  95
  96         film_changed (Film::AUDIO_PROCESSOR);
  97
  98         seek (DCPTime (), true);
  99 }
 100
 101 void
 102 Player::setup_pieces ()
 103 {
 104         _pieces.clear ();
 105
 106         BOOST_FOREACH (shared_ptr<Content> i, _playlist->content ()) {
 107
 108                 if (!i->paths_valid ()) {
 109                         continue;
 110                 }
 111
 112                 shared_ptr<Decoder> decoder = decoder_factory (i, _film->log());
 113                 FrameRateChange frc (i->active_video_frame_rate(), _film->video_frame_rate());
 114
 115                 if (!decoder) {
 116                         /* Not something that we can decode; e.g. Atmos content */
 117                         continue;
 118                 }
 119
 120                 if (decoder->video && _ignore_video) {
 121                         decoder->video->set_ignore ();
 122                 }
 123
 124                 if (decoder->audio && _ignore_audio) {
 125                         decoder->audio->set_ignore ();
 126                 }
 127
 128                 shared_ptr<DCPDecoder> dcp = dynamic_pointer_cast<DCPDecoder> (decoder);
 129                 if (dcp && _play_referenced) {
 130                         dcp->set_decode_referenced ();
 131                 }
 132
 133                 shared_ptr<Piece> piece (new Piece (i, decoder, frc));
 134                 _pieces.push_back (piece);
 135
 136                 if (decoder->video) {
 137                         decoder->video->Data.connect (bind (&Player::video, this, weak_ptr<Piece> (piece), _1));
 138                 }
 139
 140                 if (decoder->audio) {
 141                         decoder->audio->Data.connect (bind (&Player::audio, this, weak_ptr<Piece> (piece), _1, _2));
 142                 }
 143
 144                 if (decoder->subtitle) {
 145                         decoder->subtitle->ImageStart.connect (bind (&Player::image_subtitle_start, this, weak_ptr<Piece> (piece), _1));
 146                         decoder->subtitle->TextStart.connect (bind (&Player::text_subtitle_start, this, weak_ptr<Piece> (piece), _1));
 147                         decoder->subtitle->Stop.connect (bind (&Player::subtitle_stop, this, weak_ptr<Piece> (piece), _1));
 148                 }
 149         }
 150
 151         BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
 152                 if (i->content->audio) {
 153                         BOOST_FOREACH (AudioStreamPtr j, i->content->audio->streams()) {
 154                                 _stream_states[j] = StreamState (i, i->content->position ());
 155                         }
 156                 }
 157         }
 158
 159         if (!_play_referenced) {
 160                 BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
 161                         shared_ptr<DCPContent> dc = dynamic_pointer_cast<DCPContent> (i->content);
 162                         if (dc) {
 163                                 if (dc->reference_video()) {
 164                                         _no_video.push_back (DCPTimePeriod (dc->position(), dc->end()));
 165                                 }
 166                                 if (dc->reference_audio()) {
 167                                         _no_audio.push_back (DCPTimePeriod (dc->position(), dc->end()));
 168                                 }
 169                         }
 170                 }
 171         }
 172
 173         _last_video_time = DCPTime ();
 174         _last_audio_time = DCPTime ();
 175         _have_valid_pieces = true;
 176 }
 177
 178 void
 179 Player::playlist_content_changed (weak_ptr<Content> w, int property, bool frequent)
 180 {
 181         shared_ptr<Content> c = w.lock ();
 182         if (!c) {
 183                 return;
 184         }
 185
 186         if (
 187                 property == ContentProperty::POSITION ||
 188                 property == ContentProperty::LENGTH ||
 189                 property == ContentProperty::TRIM_START ||
 190                 property == ContentProperty::TRIM_END ||
 191                 property == ContentProperty::PATH ||
 192                 property == VideoContentProperty::FRAME_TYPE ||
 193                 property == DCPContentProperty::NEEDS_ASSETS ||
 194                 property == DCPContentProperty::NEEDS_KDM ||
 195                 property == SubtitleContentProperty::COLOUR ||
 196                 property == SubtitleContentProperty::OUTLINE ||
 197                 property == SubtitleContentProperty::SHADOW ||
 198                 property == SubtitleContentProperty::EFFECT_COLOUR ||
 199                 property == FFmpegContentProperty::SUBTITLE_STREAM ||
 200                 property == VideoContentProperty::COLOUR_CONVERSION
 201                 ) {
 202
 203                 _have_valid_pieces = false;
 204                 Changed (frequent);
 205
 206         } else if (
 207                 property == SubtitleContentProperty::LINE_SPACING ||
 208                 property == SubtitleContentProperty::OUTLINE_WIDTH ||
 209                 property == SubtitleContentProperty::Y_SCALE ||
 210                 property == SubtitleContentProperty::FADE_IN ||
 211                 property == SubtitleContentProperty::FADE_OUT ||
 212                 property == ContentProperty::VIDEO_FRAME_RATE ||
 213                 property == SubtitleContentProperty::USE ||
 214                 property == SubtitleContentProperty::X_OFFSET ||
 215                 property == SubtitleContentProperty::Y_OFFSET ||
 216                 property == SubtitleContentProperty::X_SCALE ||
 217                 property == SubtitleContentProperty::FONTS ||
 218                 property == VideoContentProperty::CROP ||
 219                 property == VideoContentProperty::SCALE ||
 220                 property == VideoContentProperty::FADE_IN ||
 221                 property == VideoContentProperty::FADE_OUT
 222                 ) {
 223
 224                 Changed (frequent);
 225         }
 226 }
 227
 228 void
 229 Player::set_video_container_size (dcp::Size s)
 230 {
 231         if (s == _video_container_size) {
 232                 return;
 233         }
 234
 235         _video_container_size = s;
 236
 237         _black_image.reset (new Image (AV_PIX_FMT_RGB24, _video_container_size, true));
 238         _black_image->make_black ();
 239
 240         Changed (false);
 241 }
 242
 243 void
 244 Player::playlist_changed ()
 245 {
 246         _have_valid_pieces = false;
 247         Changed (false);
 248 }
 249
 250 void
 251 Player::film_changed (Film::Property p)
 252 {
 253         /* Here we should notice Film properties that affect our output, and
 254            alert listeners that our output now would be different to how it was
 255            last time we were run.
 256         */
 257
 258         if (p == Film::CONTAINER) {
 259                 Changed (false);
 260         } else if (p == Film::VIDEO_FRAME_RATE) {
 261                 /* Pieces contain a FrameRateChange which contains the DCP frame rate,
 262                    so we need new pieces here.
 263                 */
 264                 _have_valid_pieces = false;
 265                 Changed (false);
 266         } else if (p == Film::AUDIO_PROCESSOR) {
 267                 if (_film->audio_processor ()) {
 268                         _audio_processor = _film->audio_processor()->clone (_film->audio_frame_rate ());
 269                 }
 270         }
 271 }
 272
 273 list<PositionImage>
 274 Player::transform_image_subtitles (list<ImageSubtitle> subs) const
 275 {
 276         list<PositionImage> all;
 277
 278         for (list<ImageSubtitle>::const_iterator i = subs.begin(); i != subs.end(); ++i) {
 279                 if (!i->image) {
 280                         continue;
 281                 }
 282
 283                 /* We will scale the subtitle up to fit _video_container_size */
 284                 dcp::Size scaled_size (i->rectangle.width * _video_container_size.width, i->rectangle.height * _video_container_size.height);
 285
 286                 /* Then we need a corrective translation, consisting of two parts:
 287                  *
 288                  * 1.  that which is the result of the scaling of the subtitle by _video_container_size; this will be
 289                  *     rect.x * _video_container_size.width and rect.y * _video_container_size.height.
 290                  *
 291                  * 2.  that to shift the origin of the scale by subtitle_scale to the centre of the subtitle; this will be
 292                  *     (width_before_subtitle_scale * (1 - subtitle_x_scale) / 2) and
 293                  *     (height_before_subtitle_scale * (1 - subtitle_y_scale) / 2).
 294                  *
 295                  * Combining these two translations gives these expressions.
 296                  */
 297
 298                 all.push_back (
 299                         PositionImage (
 300                                 i->image->scale (
 301                                         scaled_size,
 302                                         dcp::YUV_TO_RGB_REC601,
 303                                         i->image->pixel_format (),
 304                                         true,
 305                                         _fast
 306                                         ),
 307                                 Position<int> (
 308                                         lrint (_video_container_size.width * i->rectangle.x),
 309                                         lrint (_video_container_size.height * i->rectangle.y)
 310                                         )
 311                                 )
 312                         );
 313         }
 314
 315         return all;
 316 }
 317
 318 shared_ptr<PlayerVideo>
 319 Player::black_player_video_frame () const
 320 {
 321         return shared_ptr<PlayerVideo> (
 322                 new PlayerVideo (
 323                         shared_ptr<const ImageProxy> (new RawImageProxy (_black_image)),
 324                         Crop (),
 325                         optional<double> (),
 326                         _video_container_size,
 327                         _video_container_size,
 328                         EYES_BOTH,
 329                         PART_WHOLE,
 330                         PresetColourConversion::all().front().conversion
 331                 )
 332         );
 333 }
 334
 335 Frame
 336 Player::dcp_to_content_video (shared_ptr<const Piece> piece, DCPTime t) const
 337 {
 338         DCPTime s = t - piece->content->position ();
 339         s = min (piece->content->length_after_trim(), s);
 340         s = max (DCPTime(), s + DCPTime (piece->content->trim_start(), piece->frc));
 341
 342         /* It might seem more logical here to convert s to a ContentTime (using the FrameRateChange)
 343            then convert that ContentTime to frames at the content's rate.  However this fails for
 344            situations like content at 29.9978733fps, DCP at 30fps.  The accuracy of the Time type is not
 345            enough to distinguish between the two with low values of time (e.g. 3200 in Time units).
 346
 347            Instead we convert the DCPTime using the DCP video rate then account for any skip/repeat.
 348         */
 349         return s.frames_floor (piece->frc.dcp) / piece->frc.factor ();
 350 }
 351
 352 DCPTime
 353 Player::content_video_to_dcp (shared_ptr<const Piece> piece, Frame f) const
 354 {
 355         /* See comment in dcp_to_content_video */
 356         DCPTime const d = DCPTime::from_frames (f * piece->frc.factor(), piece->frc.dcp) - DCPTime (piece->content->trim_start (), piece->frc);
 357         return max (DCPTime (), d + piece->content->position ());
 358 }
 359
 360 Frame
 361 Player::dcp_to_resampled_audio (shared_ptr<const Piece> piece, DCPTime t) const
 362 {
 363         DCPTime s = t - piece->content->position ();
 364         s = min (piece->content->length_after_trim(), s);
 365         /* See notes in dcp_to_content_video */
 366         return max (DCPTime (), DCPTime (piece->content->trim_start (), piece->frc) + s).frames_floor (_film->audio_frame_rate ());
 367 }
 368
 369 DCPTime
 370 Player::resampled_audio_to_dcp (shared_ptr<const Piece> piece, Frame f) const
 371 {
 372         /* See comment in dcp_to_content_video */
 373         DCPTime const d = DCPTime::from_frames (f, _film->audio_frame_rate()) - DCPTime (piece->content->trim_start(), piece->frc);
 374         return max (DCPTime (), d + piece->content->position ());
 375 }
 376
 377 ContentTime
 378 Player::dcp_to_content_time (shared_ptr<const Piece> piece, DCPTime t) const
 379 {
 380         DCPTime s = t - piece->content->position ();
 381         s = min (piece->content->length_after_trim(), s);
 382         return max (ContentTime (), ContentTime (s, piece->frc) + piece->content->trim_start());
 383 }
 384
 385 DCPTime
 386 Player::content_time_to_dcp (shared_ptr<const Piece> piece, ContentTime t) const
 387 {
 388         return max (DCPTime (), DCPTime (t - piece->content->trim_start(), piece->frc) + piece->content->position());
 389 }
 390
 391 list<shared_ptr<Font> >
 392 Player::get_subtitle_fonts ()
 393 {
 394         if (!_have_valid_pieces) {
 395                 setup_pieces ();
 396         }
 397
 398         list<shared_ptr<Font> > fonts;
 399         BOOST_FOREACH (shared_ptr<Piece>& p, _pieces) {
 400                 if (p->content->subtitle) {
 401                         /* XXX: things may go wrong if there are duplicate font IDs
 402                            with different font files.
 403                         */
 404                         list<shared_ptr<Font> > f = p->content->subtitle->fonts ();
 405                         copy (f.begin(), f.end(), back_inserter (fonts));
 406                 }
 407         }
 408
 409         return fonts;
 410 }
 411
 412 /** Set this player never to produce any video data */
 413 void
 414 Player::set_ignore_video ()
 415 {
 416         _ignore_video = true;
 417 }
 418
 419 /** Set whether or not this player should always burn text subtitles into the image,
 420  *  regardless of the content settings.
 421  *  @param burn true to always burn subtitles, false to obey content settings.
 422  */
 423 void
 424 Player::set_always_burn_subtitles (bool burn)
 425 {
 426         _always_burn_subtitles = burn;
 427 }
 428
 429 void
 430 Player::set_fast ()
 431 {
 432         _fast = true;
 433         _have_valid_pieces = false;
 434 }
 435
 436 void
 437 Player::set_play_referenced ()
 438 {
 439         _play_referenced = true;
 440         _have_valid_pieces = false;
 441 }
 442
 443 list<ReferencedReelAsset>
 444 Player::get_reel_assets ()
 445 {
 446         list<ReferencedReelAsset> a;
 447
 448         BOOST_FOREACH (shared_ptr<Content> i, _playlist->content ()) {
 449                 shared_ptr<DCPContent> j = dynamic_pointer_cast<DCPContent> (i);
 450                 if (!j) {
 451                         continue;
 452                 }
 453
 454                 scoped_ptr<DCPDecoder> decoder;
 455                 try {
 456                         decoder.reset (new DCPDecoder (j, _film->log()));
 457                 } catch (...) {
 458                         return a;
 459                 }
 460
 461                 int64_t offset = 0;
 462                 BOOST_FOREACH (shared_ptr<dcp::Reel> k, decoder->reels()) {
 463
 464                         DCPOMATIC_ASSERT (j->video_frame_rate ());
 465                         double const cfr = j->video_frame_rate().get();
 466                         Frame const trim_start = j->trim_start().frames_round (cfr);
 467                         Frame const trim_end = j->trim_end().frames_round (cfr);
 468                         int const ffr = _film->video_frame_rate ();
 469
 470                         DCPTime const from = i->position() + DCPTime::from_frames (offset, _film->video_frame_rate());
 471                         if (j->reference_video ()) {
 472                                 shared_ptr<dcp::ReelAsset> ra = k->main_picture ();
 473                                 DCPOMATIC_ASSERT (ra);
 474                                 ra->set_entry_point (ra->entry_point() + trim_start);
 475                                 ra->set_duration (ra->duration() - trim_start - trim_end);
 476                                 a.push_back (
 477                                         ReferencedReelAsset (ra, DCPTimePeriod (from, from + DCPTime::from_frames (ra->duration(), ffr)))
 478                                         );
 479                         }
 480
 481                         if (j->reference_audio ()) {
 482                                 shared_ptr<dcp::ReelAsset> ra = k->main_sound ();
 483                                 DCPOMATIC_ASSERT (ra);
 484                                 ra->set_entry_point (ra->entry_point() + trim_start);
 485                                 ra->set_duration (ra->duration() - trim_start - trim_end);
 486                                 a.push_back (
 487                                         ReferencedReelAsset (ra, DCPTimePeriod (from, from + DCPTime::from_frames (ra->duration(), ffr)))
 488                                         );
 489                         }
 490
 491                         if (j->reference_subtitle ()) {
 492                                 shared_ptr<dcp::ReelAsset> ra = k->main_subtitle ();
 493                                 DCPOMATIC_ASSERT (ra);
 494                                 ra->set_entry_point (ra->entry_point() + trim_start);
 495                                 ra->set_duration (ra->duration() - trim_start - trim_end);
 496                                 a.push_back (
 497                                         ReferencedReelAsset (ra, DCPTimePeriod (from, from + DCPTime::from_frames (ra->duration(), ffr)))
 498                                         );
 499                         }
 500
 501                         /* Assume that main picture duration is the length of the reel */
 502                         offset += k->main_picture()->duration ();
 503                 }
 504         }
 505
 506         return a;
 507 }
 508
 509 bool
 510 Player::pass ()
 511 {
 512         if (!_have_valid_pieces) {
 513                 setup_pieces ();
 514         }
 515
 516         bool filled = false;
 517
 518         if (_last_video_time && !_playlist->video_content_at(*_last_video_time) && *_last_video_time < _playlist->length()) {
 519                 /* _last_video_time is the time just after the last video we emitted, and there is no video content
 520                    at this time so we need to emit some black.
 521                 */
 522                 emit_video (black_player_video_frame(), *_last_video_time);
 523                 filled = true;
 524         } else if (_playlist->length() == DCPTime()) {
 525                 /* Special case of an empty Film; just give one black frame */
 526                 emit_video (black_player_video_frame(), DCPTime());
 527                 filled = true;
 528         }
 529
 530         if (_last_audio_time && !_playlist->audio_content_at(*_last_audio_time) && *_last_audio_time < _playlist->length()) {
 531                 /* _last_audio_time is the time just after the last audio we emitted.  There is no audio here
 532                    so we need to emit some silence.
 533                 */
 534                 shared_ptr<Content> next = _playlist->next_audio_content(*_last_audio_time);
 535                 DCPTimePeriod period (*_last_audio_time, next ? next->position() : _playlist->length());
 536                 if (period.duration() > one_video_frame()) {
 537                         period = DCPTimePeriod (*_last_audio_time, *_last_audio_time + one_video_frame());
 538                 }
 539                 fill_audio (period);
 540                 filled = true;
 541         }
 542
 543         /* Now pass() the decoder which is farthest behind where we are */
 544
 545         shared_ptr<Piece> earliest;
 546         DCPTime earliest_content;
 547
 548         BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
 549                 if (!i->done) {
 550                         DCPTime const t = content_time_to_dcp (i, i->decoder->position());
 551                         if (!earliest || t < earliest_content) {
 552                                 earliest_content = t;
 553                                 earliest = i;
 554                         }
 555                 }
 556         }
 557
 558         if (!filled && earliest) {
 559                 earliest->done = earliest->decoder->pass ();
 560         }
 561
 562         /* Emit any audio that is ready */
 563
 564         DCPTime pull_to = _playlist->length ();
 565         for (map<AudioStreamPtr, StreamState>::const_iterator i = _stream_states.begin(); i != _stream_states.end(); ++i) {
 566                 if (!i->second.piece->done && i->second.last_push_end < pull_to) {
 567                         pull_to = i->second.last_push_end;
 568                 }
 569         }
 570
 571         list<pair<shared_ptr<AudioBuffers>, DCPTime> > audio = _audio_merger.pull (pull_to);
 572         for (list<pair<shared_ptr<AudioBuffers>, DCPTime> >::iterator i = audio.begin(); i != audio.end(); ++i) {
 573                 if (_last_audio_time && i->second < *_last_audio_time) {
 574                         /* There has been an accurate seek and we have received some audio before the seek time;
 575                            discard it.
 576                         */
 577                         pair<shared_ptr<AudioBuffers>, DCPTime> cut = discard_audio (i->first, i->second, *_last_audio_time);
 578                         if (!cut.first) {
 579                                 continue;
 580                         }
 581                         *i = cut;
 582                 }
 583
 584                 if (_last_audio_time) {
 585                         fill_audio (DCPTimePeriod (*_last_audio_time, i->second));
 586                 }
 587
 588                 emit_audio (i->first, i->second);
 589         }
 590
 591         return !earliest && !filled;
 592 }
 593
 594 optional<PositionImage>
 595 Player::subtitles_for_frame (DCPTime time) const
 596 {
 597         list<PositionImage> subtitles;
 598
 599         BOOST_FOREACH (PlayerSubtitles i, _active_subtitles.get_burnt (time, _always_burn_subtitles)) {
 600
 601                 /* Image subtitles */
 602                 list<PositionImage> c = transform_image_subtitles (i.image);
 603                 copy (c.begin(), c.end(), back_inserter (subtitles));
 604
 605                 /* Text subtitles (rendered to an image) */
 606                 if (!i.text.empty ()) {
 607                         list<PositionImage> s = render_subtitles (i.text, i.fonts, _video_container_size, time);
 608                         copy (s.begin(), s.end(), back_inserter (subtitles));
 609                 }
 610         }
 611
 612         if (subtitles.empty ()) {
 613                 return optional<PositionImage> ();
 614         }
 615
 616         return merge (subtitles);
 617 }
 618
 619 void
 620 Player::video (weak_ptr<Piece> wp, ContentVideo video)
 621 {
 622         shared_ptr<Piece> piece = wp.lock ();
 623         if (!piece) {
 624                 return;
 625         }
 626
 627         FrameRateChange frc(piece->content->active_video_frame_rate(), _film->video_frame_rate());
 628         if (frc.skip && (video.frame % 2) == 1) {
 629                 return;
 630         }
 631
 632         /* Time and period of the frame we will emit */
 633         DCPTime const time = content_video_to_dcp (piece, video.frame);
 634         DCPTimePeriod const period (time, time + one_video_frame());
 635
 636         /* Fill gaps that we discover now that we have some video which needs to be emitted */
 637
 638         optional<DCPTime> fill_to;
 639         if (_last_video_time) {
 640                 fill_to = _last_video_time;
 641         }
 642
 643         if (fill_to) {
 644                 /* XXX: this may not work for 3D */
 645                 BOOST_FOREACH (DCPTimePeriod i, subtract(DCPTimePeriod (*fill_to, time), _no_video)) {
 646                         for (DCPTime j = i.from; j < i.to; j += one_video_frame()) {
 647                                 LastVideoMap::const_iterator k = _last_video.find (wp);
 648                                 if (k != _last_video.end ()) {
 649                                         emit_video (k->second, j);
 650                                 } else {
 651                                         emit_video (black_player_video_frame(), j);
 652                                 }
 653                         }
 654                 }
 655         }
 656
 657         /* Discard if it's outside the content's period or if it's before the last accurate seek */
 658         if (
 659                 time < piece->content->position() ||
 660                 time >= piece->content->end() ||
 661                 (_last_video_time && time < *_last_video_time)) {
 662                 return;
 663         }
 664
 665         _last_video[wp].reset (
 666                 new PlayerVideo (
 667                         video.image,
 668                         piece->content->video->crop (),
 669                         piece->content->video->fade (video.frame),
 670                         piece->content->video->scale().size (
 671                                 piece->content->video, _video_container_size, _film->frame_size ()
 672                                 ),
 673                         _video_container_size,
 674                         video.eyes,
 675                         video.part,
 676                         piece->content->video->colour_conversion ()
 677                         )
 678                 );
 679
 680         emit_video (_last_video[wp], time);
 681 }
 682
 683 /** Do our common processing on some audio */
 684 void
 685 Player::audio_transform (shared_ptr<AudioContent> content, AudioStreamPtr stream, ContentAudio content_audio, DCPTime time)
 686 {
 687         DCPOMATIC_ASSERT (content_audio.audio->frames() > 0);
 688
 689         /* Gain */
 690
 691         if (content->gain() != 0) {
 692                 shared_ptr<AudioBuffers> gain (new AudioBuffers (content_audio.audio));
 693                 gain->apply_gain (content->gain ());
 694                 content_audio.audio = gain;
 695         }
 696
 697         /* Remap */
 698
 699         content_audio.audio = remap (content_audio.audio, _film->audio_channels(), stream->mapping());
 700
 701         /* Process */
 702
 703         if (_audio_processor) {
 704                 content_audio.audio = _audio_processor->run (content_audio.audio, _film->audio_channels ());
 705         }
 706
 707         /* Push */
 708
 709         _audio_merger.push (content_audio.audio, time);
 710         DCPOMATIC_ASSERT (_stream_states.find (stream) != _stream_states.end ());
 711         _stream_states[stream].last_push_end = time + DCPTime::from_frames (content_audio.audio->frames(), _film->audio_frame_rate());
 712 }
 713
 714 void
 715 Player::audio (weak_ptr<Piece> wp, AudioStreamPtr stream, ContentAudio content_audio)
 716 {
 717         DCPOMATIC_ASSERT (content_audio.audio->frames() > 0);
 718
 719         shared_ptr<Piece> piece = wp.lock ();
 720         if (!piece) {
 721                 return;
 722         }
 723
 724         shared_ptr<AudioContent> content = piece->content->audio;
 725         DCPOMATIC_ASSERT (content);
 726
 727         /* Compute time in the DCP */
 728         DCPTime time = resampled_audio_to_dcp (piece, content_audio.frame) + DCPTime::from_seconds (content->delay() / 1000.0);
 729         /* And the end of this block in the DCP */
 730         DCPTime end = time + DCPTime::from_frames(content_audio.audio->frames(), content->resampled_frame_rate());
 731
 732         /* Remove anything that comes before the start or after the end of the content */
 733         if (time < piece->content->position()) {
 734                 pair<shared_ptr<AudioBuffers>, DCPTime> cut = discard_audio (content_audio.audio, time, piece->content->position());
 735                 if (!cut.first) {
 736                         /* This audio is entirely discarded */
 737                         return;
 738                 }
 739                 content_audio.audio = cut.first;
 740                 time = cut.second;
 741         } else if (time > piece->content->end()) {
 742                 /* Discard it all */
 743                 return;
 744         } else if (end > piece->content->end()) {
 745                 Frame const remaining_frames = DCPTime(piece->content->end() - time).frames_round(_film->audio_frame_rate());
 746                 if (remaining_frames == 0) {
 747                         return;
 748                 }
 749                 shared_ptr<AudioBuffers> cut (new AudioBuffers (content_audio.audio->channels(), remaining_frames));
 750                 cut->copy_from (content_audio.audio.get(), remaining_frames, 0, 0);
 751                 content_audio.audio = cut;
 752         }
 753
 754         audio_transform (content, stream, content_audio, time);
 755 }
 756
 757 void
 758 Player::image_subtitle_start (weak_ptr<Piece> wp, ContentImageSubtitle subtitle)
 759 {
 760         shared_ptr<Piece> piece = wp.lock ();
 761         if (!piece) {
 762                 return;
 763         }
 764
 765         /* Apply content's subtitle offsets */
 766         subtitle.sub.rectangle.x += piece->content->subtitle->x_offset ();
 767         subtitle.sub.rectangle.y += piece->content->subtitle->y_offset ();
 768
 769         /* Apply content's subtitle scale */
 770         subtitle.sub.rectangle.width *= piece->content->subtitle->x_scale ();
 771         subtitle.sub.rectangle.height *= piece->content->subtitle->y_scale ();
 772
 773         /* Apply a corrective translation to keep the subtitle centred after that scale */
 774         subtitle.sub.rectangle.x -= subtitle.sub.rectangle.width * (piece->content->subtitle->x_scale() - 1);
 775         subtitle.sub.rectangle.y -= subtitle.sub.rectangle.height * (piece->content->subtitle->y_scale() - 1);
 776
 777         PlayerSubtitles ps;
 778         ps.image.push_back (subtitle.sub);
 779         DCPTime from (content_time_to_dcp (piece, subtitle.from()));
 780
 781         _active_subtitles.add_from (wp, ps, from);
 782 }
 783
 784 void
 785 Player::text_subtitle_start (weak_ptr<Piece> wp, ContentTextSubtitle subtitle)
 786 {
 787         shared_ptr<Piece> piece = wp.lock ();
 788         if (!piece) {
 789                 return;
 790         }
 791
 792         PlayerSubtitles ps;
 793         DCPTime const from (content_time_to_dcp (piece, subtitle.from()));
 794
 795         BOOST_FOREACH (dcp::SubtitleString s, subtitle.subs) {
 796                 s.set_h_position (s.h_position() + piece->content->subtitle->x_offset ());
 797                 s.set_v_position (s.v_position() + piece->content->subtitle->y_offset ());
 798                 float const xs = piece->content->subtitle->x_scale();
 799                 float const ys = piece->content->subtitle->y_scale();
 800                 float size = s.size();
 801
 802                 /* Adjust size to express the common part of the scaling;
 803                    e.g. if xs = ys = 0.5 we scale size by 2.
 804                 */
 805                 if (xs > 1e-5 && ys > 1e-5) {
 806                         size *= 1 / min (1 / xs, 1 / ys);
 807                 }
 808                 s.set_size (size);
 809
 810                 /* Then express aspect ratio changes */
 811                 if (fabs (1.0 - xs / ys) > dcp::ASPECT_ADJUST_EPSILON) {
 812                         s.set_aspect_adjust (xs / ys);
 813                 }
 814
 815                 s.set_in (dcp::Time(from.seconds(), 1000));
 816                 ps.text.push_back (SubtitleString (s, piece->content->subtitle->outline_width()));
 817                 ps.add_fonts (piece->content->subtitle->fonts ());
 818         }
 819
 820         _active_subtitles.add_from (wp, ps, from);
 821 }
 822
 823 void
 824 Player::subtitle_stop (weak_ptr<Piece> wp, ContentTime to)
 825 {
 826         if (!_active_subtitles.have (wp)) {
 827                 return;
 828         }
 829
 830         shared_ptr<Piece> piece = wp.lock ();
 831         if (!piece) {
 832                 return;
 833         }
 834
 835         DCPTime const dcp_to = content_time_to_dcp (piece, to);
 836
 837         pair<PlayerSubtitles, DCPTime> from = _active_subtitles.add_to (wp, dcp_to);
 838
 839         if (piece->content->subtitle->use() && !_always_burn_subtitles && !piece->content->subtitle->burn()) {
 840                 Subtitle (from.first, DCPTimePeriod (from.second, dcp_to));
 841         }
 842 }
 843
 844 void
 845 Player::seek (DCPTime time, bool accurate)
 846 {
 847         if (_audio_processor) {
 848                 _audio_processor->flush ();
 849         }
 850
 851         _audio_merger.clear ();
 852         _active_subtitles.clear ();
 853
 854         BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
 855                 if (time < i->content->position()) {
 856                         /* Before; seek to 0 */
 857                         i->decoder->seek (ContentTime(), accurate);
 858                         i->done = false;
 859                 } else if (i->content->position() <= time && time < i->content->end()) {
 860                         /* During; seek to position */
 861                         i->decoder->seek (dcp_to_content_time (i, time), accurate);
 862                         i->done = false;
 863                 } else {
 864                         /* After; this piece is done */
 865                         i->done = true;
 866                 }
 867         }
 868
 869         if (accurate) {
 870                 _last_video_time = time;
 871                 _last_audio_time = time;
 872         } else {
 873                 _last_video_time = optional<DCPTime>();
 874                 _last_audio_time = optional<DCPTime>();
 875         }
 876
 877         _last_video.clear ();
 878 }
 879
 880 void
 881 Player::emit_video (shared_ptr<PlayerVideo> pv, DCPTime time)
 882 {
 883         optional<PositionImage> subtitles = subtitles_for_frame (time);
 884         if (subtitles) {
 885                 pv->set_subtitle (subtitles.get ());
 886         }
 887
 888         Video (pv, time);
 889
 890         if (pv->eyes() == EYES_BOTH || pv->eyes() == EYES_RIGHT) {
 891                 _last_video_time = time + one_video_frame();
 892                 _active_subtitles.clear_before (time);
 893         }
 894 }
 895
 896 void
 897 Player::emit_audio (shared_ptr<AudioBuffers> data, DCPTime time)
 898 {
 899         Audio (data, time);
 900         _last_audio_time = time + DCPTime::from_frames (data->frames(), _film->audio_frame_rate());
 901 }
 902
 903 void
 904 Player::fill_audio (DCPTimePeriod period)
 905 {
 906         if (period.from == period.to) {
 907                 return;
 908         }
 909
 910         DCPOMATIC_ASSERT (period.from < period.to);
 911
 912         BOOST_FOREACH (DCPTimePeriod i, subtract(period, _no_audio)) {
 913                 DCPTime t = i.from;
 914                 while (t < i.to) {
 915                         DCPTime block = min (DCPTime::from_seconds (0.5), i.to - t);
 916                         Frame const samples = block.frames_round(_film->audio_frame_rate());
 917                         if (samples) {
 918                                 shared_ptr<AudioBuffers> silence (new AudioBuffers (_film->audio_channels(), samples));
 919                                 silence->make_silent ();
 920                                 emit_audio (silence, t);
 921                         }
 922                         t += block;
 923                 }
 924         }
 925 }
 926
 927 DCPTime
 928 Player::one_video_frame () const
 929 {
 930         return DCPTime::from_frames (1, _film->video_frame_rate ());
 931 }
 932
 933 pair<shared_ptr<AudioBuffers>, DCPTime>
 934 Player::discard_audio (shared_ptr<const AudioBuffers> audio, DCPTime time, DCPTime discard_to) const
 935 {
 936         DCPTime const discard_time = discard_to - time;
 937         Frame const discard_frames = discard_time.frames_round(_film->audio_frame_rate());
 938         Frame remaining_frames = audio->frames() - discard_frames;
 939         if (remaining_frames <= 0) {
 940                 return make_pair(shared_ptr<AudioBuffers>(), DCPTime());
 941         }
 942         shared_ptr<AudioBuffers> cut (new AudioBuffers (audio->channels(), remaining_frames));
 943         cut->copy_from (audio.get(), remaining_frames, discard_frames, 0);
 944         return make_pair(cut, time + discard_time);
 945 }