Difficult to see how any unprotected write with multiple readers
[dcpomatic.git] / src / lib / writer.cc
index 47c6b838142619a355cab1f0fbc298f84586df9b..699f220c4df31fdef6dfbae02086515119e60fd6 100644 (file)
@@ -1,19 +1,20 @@
 /*
-    Copyright (C) 2012-2015 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2019 Carl Hetherington <cth@carlh.net>
 
-    This program is free software; you can redistribute it and/or modify
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.
 
-    This program is distributed in the hope that it will be useful,
+    DCP-o-matic is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
 
 */
 
@@ -22,6 +23,7 @@
 #include "film.h"
 #include "ratio.h"
 #include "log.h"
+#include "dcpomatic_log.h"
 #include "dcp_video.h"
 #include "dcp_content_type.h"
 #include "audio_mapping.h"
 #include "job.h"
 #include "cross.h"
 #include "audio_buffers.h"
-#include "md5_digester.h"
 #include "version.h"
 #include "font.h"
 #include "util.h"
 #include "reel_writer.h"
+#include "text_content.h"
 #include <dcp/cpl.h>
+#include <dcp/locale_convert.h>
 #include <boost/foreach.hpp>
 #include <fstream>
 #include <cerrno>
 #include <iostream>
+#include <cfloat>
 
 #include "i18n.h"
 
-#define LOG_GENERAL(...) _film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_GENERAL);
-#define LOG_GENERAL_NC(...) _film->log()->log (__VA_ARGS__, LogEntry::TYPE_GENERAL);
-#define LOG_DEBUG_ENCODE(...) _film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_DEBUG_ENCODE);
-#define LOG_TIMING(...) _film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_TIMING);
-#define LOG_WARNING_NC(...) _film->log()->log (__VA_ARGS__, LogEntry::TYPE_WARNING);
-#define LOG_WARNING(...) _film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_WARNING);
-#define LOG_ERROR(...) _film->log()->log (String::compose (__VA_ARGS__), LogEntry::TYPE_ERROR);
-
 /* OS X strikes again */
 #undef set_key
 
@@ -58,51 +54,64 @@ using std::pair;
 using std::string;
 using std::list;
 using std::cout;
+using std::map;
+using std::min;
+using std::max;
+using std::vector;
 using boost::shared_ptr;
 using boost::weak_ptr;
 using boost::dynamic_pointer_cast;
+using boost::optional;
 using dcp::Data;
+using namespace dcpomatic;
 
 Writer::Writer (shared_ptr<const Film> film, weak_ptr<Job> j)
        : _film (film)
        , _job (j)
-       , _thread (0)
        , _finish (false)
        , _queued_full_in_memory (0)
-       , _maximum_frames_in_memory (0)
+       /* These will be reset to sensible values when J2KEncoder is created */
+       , _maximum_frames_in_memory (8)
+       , _maximum_queue_size (8)
        , _full_written (0)
        , _fake_written (0)
        , _repeat_written (0)
        , _pushed_to_disk (0)
 {
-       /* Remove any old DCP */
-       boost::filesystem::remove_all (_film->dir (_film->dcp_name ()));
-
        shared_ptr<Job> job = _job.lock ();
        DCPOMATIC_ASSERT (job);
 
-       BOOST_FOREACH (DCPTimePeriod p, _film->reels ()) {
-               _reels.push_back (ReelWriter (film, p, job));
+       int reel_index = 0;
+       list<DCPTimePeriod> const reels = _film->reels ();
+       BOOST_FOREACH (DCPTimePeriod p, reels) {
+               _reels.push_back (ReelWriter (film, p, job, reel_index++, reels.size(), _film->content_summary(p)));
        }
 
-       /* We can keep track of the current audio and subtitle reels easily because audio
-          and subs arrive to the Writer in sequence.  This is not so for video.
+       _last_written.resize (reels.size());
+
+       /* We can keep track of the current audio, subtitle and closed caption reels easily because audio
+          and captions arrive to the Writer in sequence.  This is not so for video.
        */
        _audio_reel = _reels.begin ();
        _subtitle_reel = _reels.begin ();
+       BOOST_FOREACH (DCPTextTrack i, _film->closed_caption_tracks()) {
+               _caption_reels[i] = _reels.begin ();
+       }
 
        /* Check that the signer is OK if we need one */
-       if (_film->is_signed() && !Config::instance()->signer_chain()->valid ()) {
-               throw InvalidSignerError ();
+       string reason;
+       if (_film->is_signed() && !Config::instance()->signer_chain()->valid(&reason)) {
+               throw InvalidSignerError (reason);
        }
-
-       job->sub (_("Encoding image data"));
 }
 
 void
 Writer::start ()
 {
-       _thread = new boost::thread (boost::bind (&Writer::thread, this));
+       _thread = boost::thread (boost::bind(&Writer::thread, this));
+#ifdef DCPOMATIC_LINUX
+       pthread_setname_np (_thread.native_handle(), "writer");
+#endif
 }
 
 Writer::~Writer ()
@@ -122,7 +131,9 @@ Writer::write (Data encoded, Frame frame, Eyes eyes)
        boost::mutex::scoped_lock lock (_state_mutex);
 
        while (_queued_full_in_memory > _maximum_frames_in_memory) {
-               /* The queue is too big; wait until that is sorted out */
+               /* There are too many full frames in memory; wake the main writer thread and
+                  wait until it sorts everything out */
+               _empty_condition.notify_all ();
                _full_condition.wait (lock);
        }
 
@@ -165,8 +176,11 @@ Writer::repeat (Frame frame, Eyes eyes)
 {
        boost::mutex::scoped_lock lock (_state_mutex);
 
-       while (_queued_full_in_memory > _maximum_frames_in_memory) {
-               /* The queue is too big; wait until that is sorted out */
+       while (_queue.size() > _maximum_queue_size && have_sequenced_image_at_queue_head()) {
+               /* The queue is too big, and the main writer thread can run and fix it, so
+                  wake it and wait until it has done.
+               */
+               _empty_condition.notify_all ();
                _full_condition.wait (lock);
        }
 
@@ -193,26 +207,27 @@ Writer::fake_write (Frame frame, Eyes eyes)
 {
        boost::mutex::scoped_lock lock (_state_mutex);
 
-       while (_queued_full_in_memory > _maximum_frames_in_memory) {
-               /* The queue is too big; wait until that is sorted out */
+       while (_queue.size() > _maximum_queue_size && have_sequenced_image_at_queue_head()) {
+               /* The queue is too big, and the main writer thread can run and fix it, so
+                  wake it and wait until it has done.
+               */
+               _empty_condition.notify_all ();
                _full_condition.wait (lock);
        }
 
        size_t const reel = video_reel (frame);
-       Frame const reel_frame = frame - _reels[reel].start ();
-
-       FILE* file = fopen_boost (_film->info_file(_reels[reel].period()), "rb");
-       if (!file) {
-               throw ReadFileError (_film->info_file(_reels[reel].period()));
-       }
-       dcp::FrameInfo info = _reels[reel].read_frame_info (file, reel_frame, eyes);
-       fclose (file);
+       Frame const frame_in_reel = frame - _reels[reel].start ();
 
        QueueItem qi;
        qi.type = QueueItem::FAKE;
-       qi.size = info.size;
+
+       {
+               shared_ptr<InfoFileHandle> info_file = _film->info_file_handle(_reels[reel].period(), true);
+               qi.size = _reels[reel].read_frame_info(info_file, frame_in_reel, eyes).size;
+       }
+
        qi.reel = reel;
-       qi.frame = reel_frame;
+       qi.frame = frame_in_reel;
        if (_film->three_d() && eyes == EYES_BOTH) {
                qi.eyes = EYES_LEFT;
                _queue.push_back (qi);
@@ -227,27 +242,68 @@ Writer::fake_write (Frame frame, Eyes eyes)
        _empty_condition.notify_all ();
 }
 
-/** Write one video frame's worth of audio frames to the DCP.
- *  @param audio Audio data or 0 if there is no audio to be written here (i.e. it is referenced).
+/** Write some audio frames to the DCP.
+ *  @param audio Audio data.
+ *  @param time Time of this data within the DCP.
  *  This method is not thread safe.
  */
 void
-Writer::write (shared_ptr<const AudioBuffers> audio)
+Writer::write (shared_ptr<const AudioBuffers> audio, DCPTime const time)
 {
-       if (_audio_reel == _reels.end ()) {
-               /* This audio is off the end of the last reel; ignore it */
-               return;
-       }
+       DCPOMATIC_ASSERT (audio);
+
+       int const afr = _film->audio_frame_rate();
 
-       _audio_reel->write (audio);
+       DCPTime const end = time + DCPTime::from_frames(audio->frames(), afr);
 
-       /* written is in video frames, not audio frames */
-       if (_audio_reel->total_written_audio_frames() >= _audio_reel->period().duration().frames_floor (_film->video_frame_rate())) {
-               ++_audio_reel;
+       /* The audio we get might span a reel boundary, and if so we have to write it in bits */
+
+       DCPTime t = time;
+       while (t < end) {
+
+               if (_audio_reel == _reels.end ()) {
+                       /* This audio is off the end of the last reel; ignore it */
+                       return;
+               }
+
+               if (end <= _audio_reel->period().to) {
+                       /* Easy case: we can write all the audio to this reel */
+                       _audio_reel->write (audio);
+                       t = end;
+               } else if (_audio_reel->period().to <= t) {
+                       /* This reel is entirely before the start of our audio; just skip the reel */
+                       ++_audio_reel;
+               } else {
+                       /* This audio is over a reel boundary; split the audio into two and write the first part */
+                       DCPTime part_lengths[2] = {
+                               _audio_reel->period().to - t,
+                               end - _audio_reel->period().to
+                       };
+
+                       Frame part_frames[2] = {
+                               part_lengths[0].frames_ceil(afr),
+                               part_lengths[1].frames_ceil(afr)
+                       };
+
+                       if (part_frames[0]) {
+                               shared_ptr<AudioBuffers> part (new AudioBuffers(audio, part_frames[0], 0));
+                               _audio_reel->write (part);
+                       }
+
+                       if (part_frames[1]) {
+                               audio.reset (new AudioBuffers(audio, part_frames[1], part_frames[0]));
+                       } else {
+                               audio.reset ();
+                       }
+
+                       ++_audio_reel;
+                       t += part_lengths[0];
+               }
        }
 }
 
-/** This must be called from Writer::thread() with an appropriate lock held */
+
+/** Caller must hold a lock on _state_mutex */
 bool
 Writer::have_sequenced_image_at_queue_head ()
 {
@@ -256,30 +312,41 @@ Writer::have_sequenced_image_at_queue_head ()
        }
 
        _queue.sort ();
-
        QueueItem const & f = _queue.front();
-       ReelWriter const & reel = _reels[f.reel];
+       return _last_written[f.reel].next(f);
+}
 
-       /* The queue should contain only EYES_LEFT/EYES_RIGHT pairs or EYES_BOTH */
 
-       if (f.eyes == EYES_BOTH) {
+bool
+Writer::LastWritten::next (QueueItem qi) const
+{
+       if (qi.eyes == EYES_BOTH) {
                /* 2D */
-               return f.frame == (reel.last_written_video_frame() + 1);
+               return qi.frame == (_frame + 1);
        }
 
        /* 3D */
 
-       if (reel.last_written_eyes() == EYES_LEFT && f.frame == reel.last_written_video_frame() && f.eyes == EYES_RIGHT) {
+       if (_eyes == EYES_LEFT && qi.frame == _frame && qi.eyes == EYES_RIGHT) {
                return true;
        }
 
-       if (reel.last_written_eyes() == EYES_RIGHT && f.frame == (reel.last_written_video_frame() + 1) && f.eyes == EYES_LEFT) {
+       if (_eyes == EYES_RIGHT && qi.frame == (_frame + 1) && qi.eyes == EYES_LEFT) {
                return true;
        }
 
        return false;
 }
 
+
+void
+Writer::LastWritten::update (QueueItem qi)
+{
+       _frame = qi.frame;
+       _eyes = qi.eyes;
+}
+
+
 void
 Writer::thread ()
 try
@@ -314,11 +381,11 @@ try
                        /* (Hopefully temporarily) log anything that was not written */
                        if (!_queue.empty() && !have_sequenced_image_at_queue_head()) {
                                LOG_WARNING (N_("Finishing writer with a left-over queue of %1:"), _queue.size());
-                               for (list<QueueItem>::const_iterator i = _queue.begin(); i != _queue.end(); ++i) {
-                                       if (i->type == QueueItem::FULL) {
-                                               LOG_WARNING (N_("- type FULL, frame %1, eyes %2"), i->frame, i->eyes);
+                               BOOST_FOREACH (QueueItem const& i, _queue) {
+                                       if (i.type == QueueItem::FULL) {
+                                               LOG_WARNING (N_("- type FULL, frame %1, eyes %2"), i.frame, (int) i.eyes);
                                        } else {
-                                               LOG_WARNING (N_("- type FAKE, size %1, frame %2, eyes %3"), i->size, i->frame, i->eyes);
+                                               LOG_WARNING (N_("- type FAKE, size %1, frame %2, eyes %3"), i.size, i.frame, (int) i.eyes);
                                        }
                                }
                        }
@@ -328,6 +395,7 @@ try
                /* Write any frames that we can write; i.e. those that are in sequence. */
                while (have_sequenced_image_at_queue_head ()) {
                        QueueItem qi = _queue.front ();
+                       _last_written[qi.reel].update (qi);
                        _queue.pop_front ();
                        if (qi.type == QueueItem::FULL && qi.encoded) {
                                --_queued_full_in_memory;
@@ -339,7 +407,7 @@ try
 
                        switch (qi.type) {
                        case QueueItem::FULL:
-                               LOG_DEBUG_ENCODE (N_("Writer FULL-writes %1 (%2)"), qi.frame, qi.eyes);
+                               LOG_DEBUG_ENCODE (N_("Writer FULL-writes %1 (%2)"), qi.frame, (int) qi.eyes);
                                if (!qi.encoded) {
                                        qi.encoded = Data (_film->j2c_path (qi.reel, qi.frame, qi.eyes, false));
                                }
@@ -348,7 +416,7 @@ try
                                break;
                        case QueueItem::FAKE:
                                LOG_DEBUG_ENCODE (N_("Writer FAKE-writes %1"), qi.frame);
-                               reel.fake_write (qi.frame, qi.eyes, qi.size);
+                               reel.fake_write (qi.size);
                                ++_fake_written;
                                break;
                        case QueueItem::REPEAT:
@@ -359,19 +427,7 @@ try
                        }
 
                        lock.lock ();
-
-                       shared_ptr<Job> job = _job.lock ();
-                       DCPOMATIC_ASSERT (job);
-                       int64_t total = _film->length().frames_round (_film->video_frame_rate ());
-                       if (_film->three_d ()) {
-                               /* _full_written and so on are incremented for each eye, so we need to double the total
-                                  frames to get the correct progress.
-                               */
-                               total *= 2;
-                       }
-                       if (total) {
-                               job->set_progress (float (_full_written + _fake_written + _repeat_written) / total);
-                       }
+                       _full_condition.notify_all ();
                }
 
                while (_queued_full_in_memory > _maximum_frames_in_memory) {
@@ -388,6 +444,8 @@ try
 
                        DCPOMATIC_ASSERT (i != _queue.rend());
                        ++_pushed_to_disk;
+                       /* For the log message below */
+                       int const awaiting = _last_written[_queue.front().reel].frame() + 1;
                        lock.unlock ();
 
                        /* i is valid here, even though we don't hold a lock on the mutex,
@@ -395,7 +453,7 @@ try
                           thread could erase the last item in the list.
                        */
 
-                       LOG_GENERAL ("Writer full; pushes %1 to disk", i->frame);
+                       LOG_GENERAL ("Writer full; pushes %1 to disk while awaiting %2", i->frame, awaiting);
 
                        i->encoded->write_via_temp (
                                _film->j2c_path (i->reel, i->frame, i->eyes, true),
@@ -405,10 +463,8 @@ try
                        lock.lock ();
                        i->encoded.reset ();
                        --_queued_full_in_memory;
+                       _full_condition.notify_all ();
                }
-
-               /* The queue has probably just gone down a bit; notify anything wait()ing on _full_condition */
-               _full_condition.notify_all ();
        }
 }
 catch (...)
@@ -420,7 +476,7 @@ void
 Writer::terminate_thread (bool can_throw)
 {
        boost::mutex::scoped_lock lock (_state_mutex);
-       if (_thread == 0) {
+       if (!_thread.joinable()) {
                return;
        }
 
@@ -429,22 +485,17 @@ Writer::terminate_thread (bool can_throw)
        _full_condition.notify_all ();
        lock.unlock ();
 
-       if (_thread->joinable ()) {
-               _thread->join ();
-       }
+       _thread.join ();
 
        if (can_throw) {
                rethrow ();
        }
-
-       delete _thread;
-       _thread = 0;
 }
 
 void
 Writer::finish ()
 {
-       if (!_thread) {
+       if (!_thread.joinable()) {
                return;
        }
 
@@ -471,16 +522,39 @@ Writer::finish ()
 
        dcp.add (cpl);
 
+       /* Calculate digests for each reel in parallel */
+
+       shared_ptr<Job> job = _job.lock ();
+       job->sub (_("Computing digests"));
+
+       boost::asio::io_service service;
+       boost::thread_group pool;
+
+       shared_ptr<boost::asio::io_service::work> work (new boost::asio::io_service::work (service));
+
+       int const threads = max (1, Config::instance()->master_encoding_threads ());
+
+       for (int i = 0; i < threads; ++i) {
+               pool.create_thread (boost::bind (&boost::asio::io_service::run, &service));
+       }
+
        BOOST_FOREACH (ReelWriter& i, _reels) {
+               boost::function<void (float)> set_progress = boost::bind (&Writer::set_digest_progress, this, job.get(), _1);
+               service.post (boost::bind (&ReelWriter::calculate_digests, &i, set_progress));
+       }
 
-               shared_ptr<Job> job = _job.lock ();
-               DCPOMATIC_ASSERT (job);
-               i.calculate_digests (job);
+       work.reset ();
+       pool.join_all ();
+       service.stop ();
 
+       /* Add reels to CPL */
+
+       BOOST_FOREACH (ReelWriter& i, _reels) {
                cpl->add (i.create_reel (_reel_assets, _fonts));
        }
 
        dcp::XMLMetadata meta;
+       meta.annotation_text = cpl->annotation_text ();
        meta.creator = Config::instance()->dcp_creator ();
        if (meta.creator.empty ()) {
                meta.creator = String::compose ("DCP-o-matic %1 %2", dcpomatic_version, dcpomatic_git_commit);
@@ -492,21 +566,96 @@ Writer::finish ()
        meta.set_issue_date_now ();
 
        cpl->set_metadata (meta);
+       cpl->set_ratings (vector_to_list(_film->ratings()));
+       cpl->set_content_version_label_text (_film->content_version());
 
        shared_ptr<const dcp::CertificateChain> signer;
        if (_film->is_signed ()) {
                signer = Config::instance()->signer_chain ();
                /* We did check earlier, but check again here to be on the safe side */
-               if (!signer->valid ()) {
-                       throw InvalidSignerError ();
+               string reason;
+               if (!signer->valid (&reason)) {
+                       throw InvalidSignerError (reason);
                }
        }
 
-       dcp.write_xml (_film->interop () ? dcp::INTEROP : dcp::SMPTE, meta, signer);
+       dcp.write_xml (_film->interop () ? dcp::INTEROP : dcp::SMPTE, meta, signer, Config::instance()->dcp_metadata_filename_format());
 
        LOG_GENERAL (
                N_("Wrote %1 FULL, %2 FAKE, %3 REPEAT, %4 pushed to disk"), _full_written, _fake_written, _repeat_written, _pushed_to_disk
                );
+
+       write_cover_sheet ();
+}
+
+void
+Writer::write_cover_sheet ()
+{
+       boost::filesystem::path const cover = _film->file ("COVER_SHEET.txt");
+       FILE* f = fopen_boost (cover, "w");
+       if (!f) {
+               throw OpenFileError (cover, errno, OpenFileError::WRITE);
+       }
+
+       string text = Config::instance()->cover_sheet ();
+       boost::algorithm::replace_all (text, "$CPL_NAME", _film->name());
+       boost::algorithm::replace_all (text, "$TYPE", _film->dcp_content_type()->pretty_name());
+       boost::algorithm::replace_all (text, "$CONTAINER", _film->container()->container_nickname());
+       boost::algorithm::replace_all (text, "$AUDIO_LANGUAGE", _film->isdcf_metadata().audio_language);
+
+       optional<string> subtitle_language;
+       BOOST_FOREACH (shared_ptr<Content> i, _film->content()) {
+               BOOST_FOREACH (shared_ptr<TextContent> j, i->text) {
+                       if (j->type() == TEXT_OPEN_SUBTITLE && j->use()) {
+                               subtitle_language = j->language ();
+                       }
+               }
+       }
+       boost::algorithm::replace_all (text, "$SUBTITLE_LANGUAGE", subtitle_language.get_value_or("None"));
+
+       boost::uintmax_t size = 0;
+       for (
+               boost::filesystem::recursive_directory_iterator i = boost::filesystem::recursive_directory_iterator(_film->dir(_film->dcp_name()));
+               i != boost::filesystem::recursive_directory_iterator();
+               ++i) {
+               if (boost::filesystem::is_regular_file (i->path ())) {
+                       size += boost::filesystem::file_size (i->path ());
+               }
+       }
+
+       if (size > (1000000000L)) {
+               boost::algorithm::replace_all (text, "$SIZE", String::compose ("%1GB", dcp::locale_convert<string> (size / 1000000000.0, 1, true)));
+       } else {
+               boost::algorithm::replace_all (text, "$SIZE", String::compose ("%1MB", dcp::locale_convert<string> (size / 1000000.0, 1, true)));
+       }
+
+       pair<int, int> ch = audio_channel_types (_film->mapped_audio_channels(), _film->audio_channels());
+       string description = String::compose("%1.%2", ch.first, ch.second);
+
+       if (description == "0.0") {
+               description = _("None");
+       } else if (description == "1.0") {
+               description = _("Mono");
+       } else if (description == "2.0") {
+               description = _("Stereo");
+       }
+       boost::algorithm::replace_all (text, "$AUDIO", description);
+
+       int h, m, s, fr;
+       _film->length().split (_film->video_frame_rate(), h, m, s, fr);
+       string length;
+       if (h == 0 && m == 0) {
+               length = String::compose("%1s", s);
+       } else if (h == 0 && m > 0) {
+               length = String::compose("%1m%2s", m, s);
+       } else if (h > 0 && m > 0) {
+               length = String::compose("%1h%2m%3s", h, m, s);
+       }
+
+       boost::algorithm::replace_all (text, "$LENGTH", length);
+
+       checked_fwrite (text.c_str(), text.length(), f, cover);
+       fclose (f);
 }
 
 /** @param frame Frame index within the whole DCP.
@@ -515,6 +664,11 @@ Writer::finish ()
 bool
 Writer::can_fake_write (Frame frame) const
 {
+       if (_film->encrypted()) {
+               /* We need to re-write the frame because the asset ID is embedded in the HMAC... I think... */
+               return false;
+       }
+
        /* We have to do a proper write of the first frame so that we can set up the JPEG2000
           parameters in the asset writer.
        */
@@ -526,25 +680,51 @@ Writer::can_fake_write (Frame frame) const
        return (frame != 0 && frame < reel.first_nonexistant_frame());
 }
 
+/** @param track Closed caption track if type == TEXT_CLOSED_CAPTION */
 void
-Writer::write (PlayerSubtitles subs)
+Writer::write (PlayerText text, TextType type, optional<DCPTextTrack> track, DCPTimePeriod period)
 {
-       if (subs.text.empty ()) {
-               return;
+       vector<ReelWriter>::iterator* reel = 0;
+
+       switch (type) {
+       case TEXT_OPEN_SUBTITLE:
+               reel = &_subtitle_reel;
+               break;
+       case TEXT_CLOSED_CAPTION:
+               DCPOMATIC_ASSERT (track);
+               DCPOMATIC_ASSERT (_caption_reels.find(*track) != _caption_reels.end());
+               reel = &_caption_reels[*track];
+               break;
+       default:
+               DCPOMATIC_ASSERT (false);
        }
 
-       if (_subtitle_reel->period().to <= subs.from) {
-               ++_subtitle_reel;
+       DCPOMATIC_ASSERT (*reel != _reels.end());
+       while ((*reel)->period().to <= period.from) {
+               ++(*reel);
+               DCPOMATIC_ASSERT (*reel != _reels.end());
        }
 
-       _subtitle_reel->write (subs);
+       (*reel)->write (text, type, track, period);
 }
 
 void
 Writer::write (list<shared_ptr<Font> > fonts)
 {
-       /* Just keep a list of fonts and we'll deal with them in ::finish */
-       copy (fonts.begin (), fonts.end (), back_inserter (_fonts));
+       /* Just keep a list of unique fonts and we'll deal with them in ::finish */
+
+       BOOST_FOREACH (shared_ptr<Font> i, fonts) {
+               bool got = false;
+               BOOST_FOREACH (shared_ptr<Font> j, _fonts) {
+                       if (*i == *j) {
+                               got = true;
+                       }
+               }
+
+               if (!got) {
+                       _fonts.push_back (i);
+               }
+       }
 }
 
 bool
@@ -570,16 +750,9 @@ operator== (QueueItem const & a, QueueItem const & b)
 void
 Writer::set_encoder_threads (int threads)
 {
-       /* I think the scaling factor here should be the ratio of the longest frame
-          encode time to the shortest; if the thread count is T, longest time is L
-          and the shortest time S we could encode L/S frames per thread whilst waiting
-          for the L frame to encode so we might have to store LT/S frames.
-
-          However we don't want to use too much memory, so keep it a bit lower than we'd
-          perhaps like.  A J2K frame is typically about 1Mb so 3 here will mean we could
-          use about 240Mb with 72 encoding threads.
-       */
-       _maximum_frames_in_memory = lrint (threads * 3);
+       boost::mutex::scoped_lock lm (_state_mutex);
+       _maximum_frames_in_memory = lrint (threads * Config::instance()->frames_in_memory_multiplier());
+       _maximum_queue_size = threads * 16;
 }
 
 void
@@ -600,3 +773,20 @@ Writer::video_reel (int frame) const
        DCPOMATIC_ASSERT (i < _reels.size ());
        return i;
 }
+
+void
+Writer::set_digest_progress (Job* job, float progress)
+{
+       boost::mutex::scoped_lock lm (_digest_progresses_mutex);
+
+       _digest_progresses[boost::this_thread::get_id()] = progress;
+       float min_progress = FLT_MAX;
+       for (map<boost::thread::id, float>::const_iterator i = _digest_progresses.begin(); i != _digest_progresses.end(); ++i) {
+               min_progress = min (min_progress, i->second);
+       }
+
+       job->set_progress (min_progress);
+
+       Waker waker;
+       waker.nudge ();
+}