Fix up black-filling logic.
[dcpomatic.git] / src / lib / player.cc
index 7c2048489db81f5c9950aee6004430ebebde2f49..11440ec5e6d15d82355173162650e05b5df1f8c9 100644 (file)
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2013-2016 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2013-2017 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -87,7 +87,8 @@ Player::Player (shared_ptr<const Film> film, shared_ptr<const Playlist> playlist
        , _always_burn_subtitles (false)
        , _fast (false)
        , _play_referenced (false)
-       , _audio_merger (_film->audio_channels(), _film->audio_frame_rate())
+       , _last_seek_accurate (true)
+       , _audio_merger (_film->audio_frame_rate())
 {
        _film_changed_connection = _film->Changed.connect (bind (&Player::film_changed, this, _1));
        _playlist_changed_connection = _playlist->Changed.connect (bind (&Player::playlist_changed, this));
@@ -95,6 +96,8 @@ Player::Player (shared_ptr<const Film> film, shared_ptr<const Playlist> playlist
        set_video_container_size (_film->frame_size ());
 
        film_changed (Film::AUDIO_PROCESSOR);
+
+       seek (DCPTime (), true);
 }
 
 void
@@ -141,11 +144,36 @@ Player::setup_pieces ()
                }
 
                if (decoder->subtitle) {
-                       decoder->subtitle->ImageData.connect (bind (&Player::image_subtitle, this, weak_ptr<Piece> (piece), _1));
-                       decoder->subtitle->TextData.connect (bind (&Player::text_subtitle, this, weak_ptr<Piece> (piece), _1));
+                       decoder->subtitle->ImageStart.connect (bind (&Player::image_subtitle_start, this, weak_ptr<Piece> (piece), _1));
+                       decoder->subtitle->TextStart.connect (bind (&Player::text_subtitle_start, this, weak_ptr<Piece> (piece), _1));
+                       decoder->subtitle->Stop.connect (bind (&Player::subtitle_stop, this, weak_ptr<Piece> (piece), _1));
+               }
+       }
+
+       BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
+               if (i->content->audio) {
+                       BOOST_FOREACH (AudioStreamPtr j, i->content->audio->streams()) {
+                               _stream_states[j] = StreamState (i, i->content->position ());
+                       }
                }
        }
 
+       if (!_play_referenced) {
+               BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
+                       shared_ptr<DCPContent> dc = dynamic_pointer_cast<DCPContent> (i->content);
+                       if (dc) {
+                               if (dc->reference_video()) {
+                                       _no_video.push_back (DCPTimePeriod (dc->position(), dc->end()));
+                               }
+                               if (dc->reference_audio()) {
+                                       _no_audio.push_back (DCPTimePeriod (dc->position(), dc->end()));
+                               }
+                       }
+               }
+       }
+
+       _last_video_time = optional<DCPTime> ();
+       _last_audio_time = optional<DCPTime> ();
        _have_valid_pieces = true;
 }
 
@@ -202,10 +230,16 @@ Player::playlist_content_changed (weak_ptr<Content> w, int property, bool freque
 void
 Player::set_video_container_size (dcp::Size s)
 {
+       if (s == _video_container_size) {
+               return;
+       }
+
        _video_container_size = s;
 
        _black_image.reset (new Image (AV_PIX_FMT_RGB24, _video_container_size, true));
        _black_image->make_black ();
+
+       Changed (false);
 }
 
 void
@@ -338,7 +372,7 @@ DCPTime
 Player::resampled_audio_to_dcp (shared_ptr<const Piece> piece, Frame f) const
 {
        /* See comment in dcp_to_content_video */
-       DCPTime const d = DCPTime::from_frames (f, _film->audio_frame_rate()) - DCPTime (piece->content->trim_start (), piece->frc);
+       DCPTime const d = DCPTime::from_frames (f, _film->audio_frame_rate()) - DCPTime (piece->content->trim_start(), piece->frc);
        return max (DCPTime (), d + piece->content->position ());
 }
 
@@ -384,13 +418,6 @@ Player::set_ignore_video ()
        _ignore_video = true;
 }
 
-/** Set this player never to produce any audio data */
-void
-Player::set_ignore_audio ()
-{
-       _ignore_audio = true;
-}
-
 /** Set whether or not this player should always burn text subtitles into the image,
  *  regardless of the content settings.
  *  @param burn true to always burn subtitles, false to obey content settings.
@@ -481,23 +508,6 @@ Player::get_reel_assets ()
        return a;
 }
 
-list<shared_ptr<Piece> >
-Player::overlaps (DCPTime from, DCPTime to, boost::function<bool (Content *)> valid)
-{
-       if (!_have_valid_pieces) {
-               setup_pieces ();
-       }
-
-       list<shared_ptr<Piece> > overlaps;
-       BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
-               if (valid (i->content.get ()) && i->content->position() < to && i->content->end() > from) {
-                       overlaps.push_back (i);
-               }
-       }
-
-       return overlaps;
-}
-
 bool
 Player::pass ()
 {
@@ -518,44 +528,95 @@ Player::pass ()
                }
        }
 
-       if (!earliest) {
-               return true;
+       if (earliest) {
+               earliest->done = earliest->decoder->pass ();
+               if (earliest->done && earliest->content->audio) {
+                       /* Flush the Player audio system for this piece */
+                       BOOST_FOREACH (AudioStreamPtr i, earliest->content->audio->streams()) {
+                               audio_flush (earliest, i);
+                       }
+               }
        }
 
-       earliest->done = earliest->decoder->pass ();
+       DCPTime fill_towards = earliest ? earliest_content : _playlist->length();
+
+       optional<DCPTime> fill_from;
+       if (_last_video_time) {
+               /* No seek; fill towards the next thing that might happen (or the end of the playlist) */
+               fill_from = _last_video_time;
+       } else if (_last_seek_time && !_playlist->video_content_at(_last_seek_time.get())) {
+               /* Seek into an empty area; fill from the seek time */
+               fill_from = _last_seek_time;
+       }
+
+       if (fill_from && ((fill_towards - fill_from.get())) > one_video_frame()) {
+               emit_video (black_player_video_frame(), fill_from.get());
+       } else if (_playlist->length() == DCPTime()) {
+               emit_video (black_player_video_frame(), DCPTime());
+       }
+
+       if (!earliest && !fill_from) {
+               return true;
+       }
 
        /* Emit any audio that is ready */
 
-       optional<DCPTime> earliest_audio;
-       BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
-               if (i->decoder->audio) {
-                       DCPTime const t = i->content->position() + DCPTime (i->decoder->audio->position(), i->frc);
-                       if (!earliest_audio || t < *earliest_audio) {
-                               earliest_audio = t;
-                       }
+       DCPTime pull_from = _playlist->length ();
+       for (map<AudioStreamPtr, StreamState>::const_iterator i = _stream_states.begin(); i != _stream_states.end(); ++i) {
+               if (!i->second.piece->done && i->second.last_push_end < pull_from) {
+                       pull_from = i->second.last_push_end;
                }
        }
 
-       pair<shared_ptr<AudioBuffers>, DCPTime> audio = _audio_merger.pull (earliest_audio.get_value_or(DCPTime()));
-       if (audio.first->frames() > 0) {
-               DCPOMATIC_ASSERT (audio.second >= _last_audio_time);
-               DCPTime t = _last_audio_time;
-               while (t < audio.second) {
-                       /* Silence up to the time of this new audio */
-                       DCPTime block = min (DCPTime::from_seconds (0.5), audio.second - t);
-                       shared_ptr<AudioBuffers> silence (new AudioBuffers (_film->audio_channels(), block.frames_round(_film->audio_frame_rate())));
-                       silence->make_silent ();
-                       Audio (silence, t);
-                       t += block;
+       list<pair<shared_ptr<AudioBuffers>, DCPTime> > audio = _audio_merger.pull (pull_from);
+       for (list<pair<shared_ptr<AudioBuffers>, DCPTime> >::iterator i = audio.begin(); i != audio.end(); ++i) {
+               if (_last_audio_time && i->second < _last_audio_time.get()) {
+                       /* There has been an accurate seek and we have received some audio before the seek time;
+                          discard it.
+                       */
+                       pair<shared_ptr<AudioBuffers>, DCPTime> cut = discard_audio (i->first, i->second, *_last_audio_time);
+                       if (!cut.first) {
+                               continue;
+                       }
+                       *i = cut;
                }
 
-               Audio (audio.first, audio.second);
-               _last_audio_time = audio.second;
+               if (_last_audio_time) {
+                       fill_audio (DCPTimePeriod (_last_audio_time.get(), i->second));
+               }
+
+               Audio (i->first, i->second);
+               _last_audio_time = i->second + DCPTime::from_frames(i->first->frames(), _film->audio_frame_rate());
        }
 
        return false;
 }
 
+optional<PositionImage>
+Player::subtitles_for_frame (DCPTime time) const
+{
+       list<PositionImage> subtitles;
+
+       BOOST_FOREACH (PlayerSubtitles i, _active_subtitles.get_burnt (time, _always_burn_subtitles)) {
+
+               /* Image subtitles */
+               list<PositionImage> c = transform_image_subtitles (i.image);
+               copy (c.begin(), c.end(), back_inserter (subtitles));
+
+               /* Text subtitles (rendered to an image) */
+               if (!i.text.empty ()) {
+                       list<PositionImage> s = render_subtitles (i.text, i.fonts, _video_container_size, time);
+                       copy (s.begin(), s.end(), back_inserter (subtitles));
+               }
+       }
+
+       if (subtitles.empty ()) {
+               return optional<PositionImage> ();
+       }
+
+       return merge (subtitles);
+}
+
 void
 Player::video (weak_ptr<Piece> wp, ContentVideo video)
 {
@@ -564,52 +625,36 @@ Player::video (weak_ptr<Piece> wp, ContentVideo video)
                return;
        }
 
-       /* Time and period of the frame we will emit */
-       DCPTime const time = content_video_to_dcp (piece, video.frame.index());
-       DCPTimePeriod const period (time, time + DCPTime::from_frames (1, _film->video_frame_rate()));
-
-       /* Discard if it's outside the content's period */
-       if (time < piece->content->position() || time >= piece->content->end()) {
+       FrameRateChange frc(piece->content->active_video_frame_rate(), _film->video_frame_rate());
+       if (frc.skip && (video.frame % 2) == 1) {
                return;
        }
 
-       /* Get any subtitles */
-
-       optional<PositionImage> subtitles;
-
-       for (list<pair<PlayerSubtitles, DCPTimePeriod> >::const_iterator i = _subtitles.begin(); i != _subtitles.end(); ++i) {
-
-               if (!i->second.overlap (period)) {
-                       continue;
-               }
-
-               list<PositionImage> sub_images;
-
-               /* Image subtitles */
-               list<PositionImage> c = transform_image_subtitles (i->first.image);
-               copy (c.begin(), c.end(), back_inserter (sub_images));
-
-               /* Text subtitles (rendered to an image) */
-               if (!i->first.text.empty ()) {
-                       list<PositionImage> s = render_subtitles (i->first.text, i->first.fonts, _video_container_size, time);
-                       copy (s.begin (), s.end (), back_inserter (sub_images));
-               }
+       /* Time and period of the frame we will emit */
+       DCPTime const time = content_video_to_dcp (piece, video.frame);
+       DCPTimePeriod const period (time, time + one_video_frame());
 
-               if (!sub_images.empty ()) {
-                       subtitles = merge (sub_images);
-               }
+       /* Discard if it's outside the content's period or if it's before the last accurate seek */
+       if (
+               time < piece->content->position() ||
+               time >= piece->content->end() ||
+               (_last_seek_time && _last_seek_accurate && time < _last_seek_time.get())) {
+               return;
        }
 
-       /* Fill gaps */
+       /* Fill gaps caused by (the hopefully rare event of) a decoder not emitting contiguous video.  We have to do this here
+          as in the problematic case we are about to emit a frame which is not contiguous with the previous.
+       */
 
-       if (_last_time) {
+       if (_last_video_time) {
                /* XXX: this may not work for 3D */
-               DCPTime const frame = DCPTime::from_frames (1, _film->video_frame_rate());
-               for (DCPTime i = _last_time.get() + frame; i < time; i += frame) {
-                       if (_playlist->video_content_at(i) && _last_video) {
-                               Video (shared_ptr<PlayerVideo> (new PlayerVideo (*_last_video)), i);
-                       } else {
-                               Video (black_player_video_frame (), i);
+               BOOST_FOREACH (DCPTimePeriod i, subtract(DCPTimePeriod (_last_video_time.get(), time), _no_video)) {
+                       for (DCPTime j = i.from; j < i.to; j += one_video_frame()) {
+                               if (_last_video) {
+                                       emit_video (shared_ptr<PlayerVideo> (new PlayerVideo (*_last_video)), j);
+                               } else {
+                                       emit_video (black_player_video_frame(), j);
+                               }
                        }
                }
        }
@@ -618,71 +663,62 @@ Player::video (weak_ptr<Piece> wp, ContentVideo video)
                new PlayerVideo (
                        video.image,
                        piece->content->video->crop (),
-                       piece->content->video->fade (video.frame.index()),
+                       piece->content->video->fade (video.frame),
                        piece->content->video->scale().size (
                                piece->content->video, _video_container_size, _film->frame_size ()
                                ),
                        _video_container_size,
-                       video.frame.eyes(),
+                       video.eyes,
                        video.part,
                        piece->content->video->colour_conversion ()
                        )
                );
 
-       if (subtitles) {
-               _last_video->set_subtitle (subtitles.get ());
-       }
+       emit_video (_last_video, time);
+}
 
-       _last_time = time;
+void
+Player::audio_flush (shared_ptr<Piece> piece, AudioStreamPtr stream)
+{
+       shared_ptr<AudioContent> content = piece->content->audio;
+       DCPOMATIC_ASSERT (content);
 
-       Video (_last_video, *_last_time);
+       shared_ptr<Resampler> r = resampler (content, stream, false);
+       if (!r) {
+               return;
+       }
 
-       /* Discard any subtitles we no longer need */
+       pair<shared_ptr<const AudioBuffers>, Frame> ro = r->flush ();
+       if (ro.first->frames() == 0) {
+               return;
+       }
 
-       for (list<pair<PlayerSubtitles, DCPTimePeriod> >::iterator i = _subtitles.begin (); i != _subtitles.end(); ) {
-               list<pair<PlayerSubtitles, DCPTimePeriod> >::iterator tmp = i;
-               ++tmp;
+       ContentAudio content_audio;
+       content_audio.audio = ro.first;
+       content_audio.frame = ro.second;
 
-               if (i->second.to < time) {
-                       _subtitles.erase (i);
-               }
+       /* Compute time in the DCP */
+       DCPTime time = resampled_audio_to_dcp (piece, content_audio.frame) + DCPTime::from_seconds (content->delay() / 1000.0);
 
-               i = tmp;
-       }
+       audio_transform (content, stream, content_audio, time);
 }
 
+/** Do our common processing on some audio */
 void
-Player::audio (weak_ptr<Piece> wp, AudioStreamPtr stream, ContentAudio content_audio)
+Player::audio_transform (shared_ptr<AudioContent> content, AudioStreamPtr stream, ContentAudio content_audio, DCPTime time)
 {
-       shared_ptr<Piece> piece = wp.lock ();
-       if (!piece) {
-               return;
-       }
-
-       shared_ptr<AudioContent> content = piece->content->audio;
-       DCPOMATIC_ASSERT (content);
+       DCPOMATIC_ASSERT (content_audio.audio->frames() > 0);
 
        /* Gain */
+
        if (content->gain() != 0) {
                shared_ptr<AudioBuffers> gain (new AudioBuffers (content_audio.audio));
                gain->apply_gain (content->gain ());
                content_audio.audio = gain;
        }
 
-       /* Resample */
-       if (stream->frame_rate() != content->resampled_frame_rate()) {
-               shared_ptr<Resampler> r = resampler (content, stream, true);
-               pair<shared_ptr<const AudioBuffers>, Frame> ro = r->run (content_audio.audio, content_audio.frame);
-               content_audio.audio = ro.first;
-               content_audio.frame = ro.second;
-       }
-
-       /* XXX: end-trimming used to be checked here */
+       /* Remap */
 
-       /* Compute time in the DCP */
-       DCPTime time = resampled_audio_to_dcp (piece, content_audio.frame) + DCPTime::from_seconds (content->delay() / 1000);
-
-       /* Remap channels */
        shared_ptr<AudioBuffers> dcp_mapped (new AudioBuffers (_film->audio_channels(), content_audio.audio->frames()));
        dcp_mapped->make_silent ();
 
@@ -702,25 +738,73 @@ Player::audio (weak_ptr<Piece> wp, AudioStreamPtr stream, ContentAudio content_a
 
        content_audio.audio = dcp_mapped;
 
+       /* Process */
+
        if (_audio_processor) {
                content_audio.audio = _audio_processor->run (content_audio.audio, _film->audio_channels ());
        }
 
-       /* XXX: this may be nonsense */
-       if (time < _audio_merger.last_pull()) {
-               DCPTime const discard_time = _audio_merger.last_pull() - time;
-               Frame discard_frames = discard_time.frames_round(_film->audio_frame_rate());
-               content_audio.audio.reset (new AudioBuffers (_film->audio_channels(), content_audio.audio->frames() - discard_frames));
-               time += discard_time;
+       /* Push */
+
+       _audio_merger.push (content_audio.audio, time);
+       DCPOMATIC_ASSERT (_stream_states.find (stream) != _stream_states.end ());
+       _stream_states[stream].last_push_end = time + DCPTime::from_frames (content_audio.audio->frames(), _film->audio_frame_rate());
+}
+
+void
+Player::audio (weak_ptr<Piece> wp, AudioStreamPtr stream, ContentAudio content_audio)
+{
+       DCPOMATIC_ASSERT (content_audio.audio->frames() > 0);
+
+       shared_ptr<Piece> piece = wp.lock ();
+       if (!piece) {
+               return;
+       }
+
+       shared_ptr<AudioContent> content = piece->content->audio;
+       DCPOMATIC_ASSERT (content);
+
+       /* Resample */
+       if (stream->frame_rate() != content->resampled_frame_rate()) {
+               shared_ptr<Resampler> r = resampler (content, stream, true);
+               pair<shared_ptr<const AudioBuffers>, Frame> ro = r->run (content_audio.audio, content_audio.frame);
+               if (ro.first->frames() == 0) {
+                       return;
+               }
+               content_audio.audio = ro.first;
+               content_audio.frame = ro.second;
        }
 
-       if (content_audio.audio->frames() > 0) {
-               _audio_merger.push (content_audio.audio, time);
+       /* Compute time in the DCP */
+       DCPTime time = resampled_audio_to_dcp (piece, content_audio.frame) + DCPTime::from_seconds (content->delay() / 1000.0);
+       /* And the end of this block in the DCP */
+       DCPTime end = time + DCPTime::from_frames(content_audio.audio->frames(), content->resampled_frame_rate());
+
+       /* Remove anything that comes before the start or after the end of the content */
+       if (time < piece->content->position()) {
+               pair<shared_ptr<AudioBuffers>, DCPTime> cut = discard_audio (content_audio.audio, time, piece->content->position());
+               if (!cut.first) {
+                       /* This audio is entirely discarded */
+                       return;
+               }
+               content_audio.audio = cut.first;
+               time = cut.second;
+       } else if (time > piece->content->end()) {
+               /* Discard it all */
+               return;
+       } else if (end > piece->content->end()) {
+               Frame const remaining_frames = DCPTime(piece->content->end() - time).frames_round(_film->audio_frame_rate());
+               DCPOMATIC_ASSERT (remaining_frames > 0);
+               shared_ptr<AudioBuffers> cut (new AudioBuffers (content_audio.audio->channels(), remaining_frames));
+               cut->copy_from (content_audio.audio.get(), remaining_frames, 0, 0);
+               content_audio.audio = cut;
        }
+
+       audio_transform (content, stream, content_audio, time);
 }
 
 void
-Player::image_subtitle (weak_ptr<Piece> wp, ContentImageSubtitle subtitle)
+Player::image_subtitle_start (weak_ptr<Piece> wp, ContentImageSubtitle subtitle)
 {
        shared_ptr<Piece> piece = wp.lock ();
        if (!piece) {
@@ -741,17 +825,13 @@ Player::image_subtitle (weak_ptr<Piece> wp, ContentImageSubtitle subtitle)
 
        PlayerSubtitles ps;
        ps.image.push_back (subtitle.sub);
-       DCPTimePeriod period (content_time_to_dcp (piece, subtitle.period().from), content_time_to_dcp (piece, subtitle.period().to));
+       DCPTime from (content_time_to_dcp (piece, subtitle.from()));
 
-       if (piece->content->subtitle->use() && (piece->content->subtitle->burn() || _always_burn_subtitles)) {
-               _subtitles.push_back (make_pair (ps, period));
-       } else {
-               Subtitle (ps, period);
-       }
+       _active_subtitles.add_from (wp, ps, from);
 }
 
 void
-Player::text_subtitle (weak_ptr<Piece> wp, ContentTextSubtitle subtitle)
+Player::text_subtitle_start (weak_ptr<Piece> wp, ContentTextSubtitle subtitle)
 {
        shared_ptr<Piece> piece = wp.lock ();
        if (!piece) {
@@ -759,7 +839,7 @@ Player::text_subtitle (weak_ptr<Piece> wp, ContentTextSubtitle subtitle)
        }
 
        PlayerSubtitles ps;
-       DCPTimePeriod const period (content_time_to_dcp (piece, subtitle.period().from), content_time_to_dcp (piece, subtitle.period().to));
+       DCPTime const from (content_time_to_dcp (piece, subtitle.from()));
 
        BOOST_FOREACH (dcp::SubtitleString s, subtitle.subs) {
                s.set_h_position (s.h_position() + piece->content->subtitle->x_offset ());
@@ -781,34 +861,69 @@ Player::text_subtitle (weak_ptr<Piece> wp, ContentTextSubtitle subtitle)
                        s.set_aspect_adjust (xs / ys);
                }
 
-               s.set_in (dcp::Time(period.from.seconds(), 1000));
-               s.set_out (dcp::Time(period.to.seconds(), 1000));
+               s.set_in (dcp::Time(from.seconds(), 1000));
                ps.text.push_back (SubtitleString (s, piece->content->subtitle->outline_width()));
                ps.add_fonts (piece->content->subtitle->fonts ());
        }
 
-       if (piece->content->subtitle->use() && (piece->content->subtitle->burn() || _always_burn_subtitles)) {
-               _subtitles.push_back (make_pair (ps, period));
-       } else {
-               Subtitle (ps, period);
+       _active_subtitles.add_from (wp, ps, from);
+}
+
+void
+Player::subtitle_stop (weak_ptr<Piece> wp, ContentTime to)
+{
+       if (!_active_subtitles.have (wp)) {
+               return;
+       }
+
+       shared_ptr<Piece> piece = wp.lock ();
+       if (!piece) {
+               return;
+       }
+
+       DCPTime const dcp_to = content_time_to_dcp (piece, to);
+
+       pair<PlayerSubtitles, DCPTime> from = _active_subtitles.add_to (wp, dcp_to);
+
+       if (piece->content->subtitle->use() && !_always_burn_subtitles && !piece->content->subtitle->burn()) {
+               Subtitle (from.first, DCPTimePeriod (from.second, dcp_to));
        }
 }
 
 void
 Player::seek (DCPTime time, bool accurate)
 {
+       if (_audio_processor) {
+               _audio_processor->flush ();
+       }
+
+       for (ResamplerMap::iterator i = _resamplers.begin(); i != _resamplers.end(); ++i) {
+               i->second->flush ();
+               i->second->reset ();
+       }
+
+       _audio_merger.clear ();
+       _active_subtitles.clear ();
+
        BOOST_FOREACH (shared_ptr<Piece> i, _pieces) {
-               if (i->content->position() <= time && time < i->content->end()) {
+               if (time < i->content->position()) {
+                       /* Before; seek to 0 */
+                       i->decoder->seek (ContentTime(), accurate);
+                       i->done = false;
+               } else if (i->content->position() <= time && time < i->content->end()) {
+                       /* During; seek to position */
                        i->decoder->seek (dcp_to_content_time (i, time), accurate);
                        i->done = false;
+               } else {
+                       /* After; this piece is done */
+                       i->done = true;
                }
        }
 
-       if (accurate) {
-               _last_time = time - DCPTime::from_frames (1, _film->video_frame_rate ());
-       } else {
-               _last_time = optional<DCPTime> ();
-       }
+       _last_video_time = optional<DCPTime> ();
+       _last_audio_time = optional<DCPTime> ();
+       _last_seek_time = time;
+       _last_seek_accurate = accurate;
 }
 
 shared_ptr<Resampler>
@@ -837,3 +952,53 @@ Player::resampler (shared_ptr<const AudioContent> content, AudioStreamPtr stream
        _resamplers[make_pair(content, stream)] = r;
        return r;
 }
+
+void
+Player::emit_video (shared_ptr<PlayerVideo> pv, DCPTime time)
+{
+       optional<PositionImage> subtitles = subtitles_for_frame (time);
+       if (subtitles) {
+               pv->set_subtitle (subtitles.get ());
+       }
+       Video (pv, time);
+       _last_video_time = time + one_video_frame();
+       _active_subtitles.clear_before (time);
+}
+
+void
+Player::fill_audio (DCPTimePeriod period)
+{
+       BOOST_FOREACH (DCPTimePeriod i, subtract(period, _no_audio)) {
+               DCPTime t = i.from;
+               while (t < i.to) {
+                       DCPTime block = min (DCPTime::from_seconds (0.5), i.to - t);
+                       Frame const samples = block.frames_round(_film->audio_frame_rate());
+                       if (samples) {
+                               shared_ptr<AudioBuffers> silence (new AudioBuffers (_film->audio_channels(), samples));
+                               silence->make_silent ();
+                               Audio (silence, t);
+                       }
+                       t += block;
+               }
+       }
+}
+
+DCPTime
+Player::one_video_frame () const
+{
+       return DCPTime::from_frames (1, _film->video_frame_rate ());
+}
+
+pair<shared_ptr<AudioBuffers>, DCPTime>
+Player::discard_audio (shared_ptr<const AudioBuffers> audio, DCPTime time, DCPTime discard_to) const
+{
+       DCPTime const discard_time = discard_to - time;
+       Frame const discard_frames = discard_time.frames_round(_film->audio_frame_rate());
+       Frame remaining_frames = audio->frames() - discard_frames;
+       if (remaining_frames <= 0) {
+               return make_pair(shared_ptr<AudioBuffers>(), DCPTime());
+       }
+       shared_ptr<AudioBuffers> cut (new AudioBuffers (audio->channels(), remaining_frames));
+       cut->copy_from (audio.get(), remaining_frames, discard_frames, 0);
+       return make_pair(cut, time + discard_time);
+}