src/lib/encoder.cc

   1 /*
   2     Copyright (C) 2012 Carl Hetherington <cth@carlh.net>
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 /** @file src/encoder.h
  21  *  @brief Parent class for classes which can encode video and audio frames.
  22  */
  23
  24 #include <iostream>
  25 #include <boost/filesystem.hpp>
  26 #include <boost/lexical_cast.hpp>
  27 #include <libdcp/picture_asset.h>
  28 #include "encoder.h"
  29 #include "util.h"
  30 #include "options.h"
  31 #include "film.h"
  32 #include "log.h"
  33 #include "exceptions.h"
  34 #include "filter.h"
  35 #include "config.h"
  36 #include "dcp_video_frame.h"
  37 #include "server.h"
  38 #include "format.h"
  39 #include "cross.h"
  40 #include "writer.h"
  41
  42 #include "i18n.h"
  43
  44 using std::pair;
  45 using std::string;
  46 using std::stringstream;
  47 using std::vector;
  48 using std::list;
  49 using std::cout;
  50 using std::make_pair;
  51 using namespace boost;
  52
  53 int const Encoder::_history_size = 25;
  54
  55 /** @param f Film that we are encoding */
  56 Encoder::Encoder (shared_ptr<Film> f)
  57         : _film (f)
  58         , _video_frames_in (0)
  59         , _video_frames_out (0)
  60 #ifdef HAVE_SWRESAMPLE
  61         , _swr_context (0)
  62 #endif
  63         , _have_a_real_frame (false)
  64         , _terminate (false)
  65 {
  66
  67 }
  68
  69 Encoder::~Encoder ()
  70 {
  71         terminate_threads ();
  72         if (_writer) {
  73                 _writer->finish ();
  74         }
  75 }
  76
  77 void
  78 Encoder::process_begin ()
  79 {
  80         if (_film->audio_stream() && _film->audio_stream()->sample_rate() != _film->target_audio_sample_rate()) {
  81 #ifdef HAVE_SWRESAMPLE
  82
  83                 stringstream s;
  84                 s << String::compose (N_("Will resample audio from %1 to %2"), _film->audio_stream()->sample_rate(), _film->target_audio_sample_rate());
  85                 _film->log()->log (s.str ());
  86
  87                 /* We will be using planar float data when we call the resampler */
  88                 _swr_context = swr_alloc_set_opts (
  89                         0,
  90                         _film->audio_stream()->channel_layout(),
  91                         AV_SAMPLE_FMT_FLTP,
  92                         _film->target_audio_sample_rate(),
  93                         _film->audio_stream()->channel_layout(),
  94                         AV_SAMPLE_FMT_FLTP,
  95                         _film->audio_stream()->sample_rate(),
  96                         0, 0
  97                         );
  98
  99                 swr_init (_swr_context);
 100 #else
 101                 throw EncodeError (_("Cannot resample audio as libswresample is not present"));
 102 #endif
 103         } else {
 104 #ifdef HAVE_SWRESAMPLE
 105                 _swr_context = 0;
 106 #endif
 107         }
 108
 109         for (int i = 0; i < Config::instance()->num_local_encoding_threads (); ++i) {
 110                 _threads.push_back (new boost::thread (boost::bind (&Encoder::encoder_thread, this, (ServerDescription *) 0)));
 111         }
 112
 113         vector<ServerDescription*> servers = Config::instance()->servers ();
 114
 115         for (vector<ServerDescription*>::iterator i = servers.begin(); i != servers.end(); ++i) {
 116                 for (int j = 0; j < (*i)->threads (); ++j) {
 117                         _threads.push_back (new boost::thread (boost::bind (&Encoder::encoder_thread, this, *i)));
 118                 }
 119         }
 120
 121         _writer.reset (new Writer (_film));
 122 }
 123
 124
 125 void
 126 Encoder::process_end ()
 127 {
 128 #if HAVE_SWRESAMPLE
 129         if (_film->audio_stream() && _film->audio_stream()->channels() && _swr_context) {
 130
 131                 shared_ptr<AudioBuffers> out (new AudioBuffers (_film->audio_stream()->channels(), 256));
 132
 133                 while (1) {
 134                         int const frames = swr_convert (_swr_context, (uint8_t **) out->data(), 256, 0, 0);
 135
 136                         if (frames < 0) {
 137                                 throw EncodeError (_("could not run sample-rate converter"));
 138                         }
 139
 140                         if (frames == 0) {
 141                                 break;
 142                         }
 143
 144                         out->set_frames (frames);
 145                         write_audio (out);
 146                 }
 147
 148                 swr_free (&_swr_context);
 149         }
 150 #endif
 151
 152         boost::mutex::scoped_lock lock (_mutex);
 153
 154         _film->log()->log (String::compose (N_("Clearing queue of %1"), _queue.size ()));
 155
 156         /* Keep waking workers until the queue is empty */
 157         while (!_queue.empty ()) {
 158                 _film->log()->log (String::compose (N_("Waking with %1"), _queue.size ()), Log::VERBOSE);
 159                 _condition.notify_all ();
 160                 _condition.wait (lock);
 161         }
 162
 163         lock.unlock ();
 164
 165         terminate_threads ();
 166
 167         _film->log()->log (String::compose (N_("Mopping up %1"), _queue.size()));
 168
 169         /* The following sequence of events can occur in the above code:
 170              1. a remote worker takes the last image off the queue
 171              2. the loop above terminates
 172              3. the remote worker fails to encode the image and puts it back on the queue
 173              4. the remote worker is then terminated by terminate_threads
 174
 175              So just mop up anything left in the queue here.
 176         */
 177
 178         for (list<shared_ptr<DCPVideoFrame> >::iterator i = _queue.begin(); i != _queue.end(); ++i) {
 179                 _film->log()->log (String::compose (N_("Encode left-over frame %1"), (*i)->frame ()));
 180                 try {
 181                         _writer->write ((*i)->encode_locally(), (*i)->frame ());
 182                         frame_done ();
 183                 } catch (std::exception& e) {
 184                         _film->log()->log (String::compose (N_("Local encode failed (%1)"), e.what ()));
 185                 }
 186         }
 187
 188         _writer->finish ();
 189         _writer.reset ();
 190 }
 191
 192 /** @return an estimate of the current number of frames we are encoding per second,
 193  *  or 0 if not known.
 194  */
 195 float
 196 Encoder::current_frames_per_second () const
 197 {
 198         boost::mutex::scoped_lock lock (_history_mutex);
 199         if (int (_time_history.size()) < _history_size) {
 200                 return 0;
 201         }
 202
 203         struct timeval now;
 204         gettimeofday (&now, 0);
 205
 206         return _history_size / (seconds (now) - seconds (_time_history.back ()));
 207 }
 208
 209 /** @return Number of video frames that have been sent out */
 210 int
 211 Encoder::video_frames_out () const
 212 {
 213         boost::mutex::scoped_lock (_history_mutex);
 214         return _video_frames_out;
 215 }
 216
 217 /** Should be called when a frame has been encoded successfully.
 218  *  @param n Source frame index.
 219  */
 220 void
 221 Encoder::frame_done ()
 222 {
 223         boost::mutex::scoped_lock lock (_history_mutex);
 224
 225         struct timeval tv;
 226         gettimeofday (&tv, 0);
 227         _time_history.push_front (tv);
 228         if (int (_time_history.size()) > _history_size) {
 229                 _time_history.pop_back ();
 230         }
 231 }
 232
 233 void
 234 Encoder::process_video (shared_ptr<const Image> image, bool same, boost::shared_ptr<Subtitle> sub)
 235 {
 236         FrameRateConversion frc (_film->source_frame_rate(), _film->dcp_frame_rate());
 237
 238         if (frc.skip && (_video_frames_in % 2)) {
 239                 ++_video_frames_in;
 240                 return;
 241         }
 242
 243         boost::mutex::scoped_lock lock (_mutex);
 244
 245         /* Wait until the queue has gone down a bit */
 246         while (_queue.size() >= _threads.size() * 2 && !_terminate) {
 247                 TIMING ("decoder sleeps with queue of %1", _queue.size());
 248                 _condition.wait (lock);
 249                 TIMING ("decoder wakes with queue of %1", _queue.size());
 250         }
 251
 252         if (_terminate) {
 253                 return;
 254         }
 255
 256         if (_writer->thrown ()) {
 257                 _writer->rethrow ();
 258         }
 259
 260         if (_writer->can_fake_write (_video_frames_out)) {
 261                 _writer->fake_write (_video_frames_out);
 262                 _have_a_real_frame = false;
 263                 frame_done ();
 264         } else if (same && _have_a_real_frame) {
 265                 /* Use the last frame that we encoded. */
 266                 _writer->repeat (_video_frames_out);
 267                 frame_done ();
 268         } else {
 269                 /* Queue this new frame for encoding */
 270                 pair<string, string> const s = Filter::ffmpeg_strings (_film->filters());
 271                 TIMING ("adding to queue of %1", _queue.size ());
 272                 _queue.push_back (boost::shared_ptr<DCPVideoFrame> (
 273                                           new DCPVideoFrame (
 274                                                   image, sub, _film->format()->dcp_size(), _film->format()->dcp_padding (_film),
 275                                                   _film->subtitle_offset(), _film->subtitle_scale(),
 276                                                   _film->scaler(), _video_frames_out, _film->dcp_frame_rate(), s.second,
 277                                                   _film->colour_lut(), _film->j2k_bandwidth(),
 278                                                   _film->log()
 279                                                   )
 280                                           ));
 281
 282                 _condition.notify_all ();
 283                 _have_a_real_frame = true;
 284         }
 285
 286         ++_video_frames_in;
 287         ++_video_frames_out;
 288
 289         if (frc.repeat) {
 290                 _writer->repeat (_video_frames_out);
 291                 ++_video_frames_out;
 292                 frame_done ();
 293         }
 294 }
 295
 296 void
 297 Encoder::process_audio (shared_ptr<const AudioBuffers> data)
 298 {
 299         if (!data->frames ()) {
 300                 return;
 301         }
 302
 303 #if HAVE_SWRESAMPLE
 304         /* Maybe sample-rate convert */
 305         if (_swr_context) {
 306
 307                 /* Compute the resampled frames count and add 32 for luck */
 308                 int const max_resampled_frames = ceil ((int64_t) data->frames() * _film->target_audio_sample_rate() / _film->audio_stream()->sample_rate()) + 32;
 309
 310                 shared_ptr<AudioBuffers> resampled (new AudioBuffers (_film->audio_stream()->channels(), max_resampled_frames));
 311
 312                 /* Resample audio */
 313                 int const resampled_frames = swr_convert (
 314                         _swr_context, (uint8_t **) resampled->data(), max_resampled_frames, (uint8_t const **) data->data(), data->frames()
 315                         );
 316
 317                 if (resampled_frames < 0) {
 318                         throw EncodeError (_("could not run sample-rate converter"));
 319                 }
 320
 321                 resampled->set_frames (resampled_frames);
 322
 323                 /* And point our variables at the resampled audio */
 324                 data = resampled;
 325         }
 326 #endif
 327
 328         write_audio (data);
 329 }
 330
 331 void
 332 Encoder::terminate_threads ()
 333 {
 334         boost::mutex::scoped_lock lock (_mutex);
 335         _terminate = true;
 336         _condition.notify_all ();
 337         lock.unlock ();
 338
 339         for (list<boost::thread *>::iterator i = _threads.begin(); i != _threads.end(); ++i) {
 340                 if ((*i)->joinable ()) {
 341                         (*i)->join ();
 342                 }
 343                 delete *i;
 344         }
 345 }
 346
 347 void
 348 Encoder::encoder_thread (ServerDescription* server)
 349 {
 350         /* Number of seconds that we currently wait between attempts
 351            to connect to the server; not relevant for localhost
 352            encodings.
 353         */
 354         int remote_backoff = 0;
 355
 356         while (1) {
 357
 358                 TIMING ("encoder thread %1 sleeps", boost::this_thread::get_id());
 359                 boost::mutex::scoped_lock lock (_mutex);
 360                 while (_queue.empty () && !_terminate) {
 361                         _condition.wait (lock);
 362                 }
 363
 364                 if (_terminate) {
 365                         return;
 366                 }
 367
 368                 TIMING ("encoder thread %1 wakes with queue of %2", boost::this_thread::get_id(), _queue.size());
 369                 boost::shared_ptr<DCPVideoFrame> vf = _queue.front ();
 370                 _film->log()->log (String::compose (N_("Encoder thread %1 pops frame %2 from queue"), boost::this_thread::get_id(), vf->frame()), Log::VERBOSE);
 371                 _queue.pop_front ();
 372
 373                 lock.unlock ();
 374
 375                 shared_ptr<EncodedData> encoded;
 376
 377                 if (server) {
 378                         try {
 379                                 encoded = vf->encode_remotely (server);
 380
 381                                 if (remote_backoff > 0) {
 382                                         _film->log()->log (String::compose (N_("%1 was lost, but now she is found; removing backoff"), server->host_name ()));
 383                                 }
 384
 385                                 /* This job succeeded, so remove any backoff */
 386                                 remote_backoff = 0;
 387
 388                         } catch (std::exception& e) {
 389                                 if (remote_backoff < 60) {
 390                                         /* back off more */
 391                                         remote_backoff += 10;
 392                                 }
 393                                 _film->log()->log (
 394                                         String::compose (
 395                                                 N_("Remote encode of %1 on %2 failed (%3); thread sleeping for %4s"),
 396                                                 vf->frame(), server->host_name(), e.what(), remote_backoff)
 397                                         );
 398                         }
 399
 400                 } else {
 401                         try {
 402                                 TIMING ("encoder thread %1 begins local encode of %2", boost::this_thread::get_id(), vf->frame());
 403                                 encoded = vf->encode_locally ();
 404                                 TIMING ("encoder thread %1 finishes local encode of %2", boost::this_thread::get_id(), vf->frame());
 405                         } catch (std::exception& e) {
 406                                 _film->log()->log (String::compose (N_("Local encode failed (%1)"), e.what ()));
 407                         }
 408                 }
 409
 410                 if (encoded) {
 411                         _writer->write (encoded, vf->frame ());
 412                         frame_done ();
 413                 } else {
 414                         lock.lock ();
 415                         _film->log()->log (
 416                                 String::compose (N_("Encoder thread %1 pushes frame %2 back onto queue after failure"), boost::this_thread::get_id(), vf->frame())
 417                                 );
 418                         _queue.push_front (vf);
 419                         lock.unlock ();
 420                 }
 421
 422                 if (remote_backoff > 0) {
 423                         dvdomatic_sleep (remote_backoff);
 424                 }
 425
 426                 lock.lock ();
 427                 _condition.notify_all ();
 428         }
 429 }
 430
 431 void
 432 Encoder::write_audio (shared_ptr<const AudioBuffers> data)
 433 {
 434         AudioMapping m (_film->audio_channels ());
 435         if (m.dcp_channels() != _film->audio_channels()) {
 436
 437                 /* Remap (currently just for mono -> 5.1) */
 438
 439                 shared_ptr<AudioBuffers> b (new AudioBuffers (m.dcp_channels(), data->frames ()));
 440                 for (int i = 0; i < m.dcp_channels(); ++i) {
 441                         optional<int> s = m.dcp_to_source (static_cast<libdcp::Channel> (i));
 442                         if (!s) {
 443                                 b->make_silent (i);
 444                         } else {
 445                                 memcpy (b->data()[i], data->data()[s.get()], data->frames() * sizeof(float));
 446                         }
 447                 }
 448
 449                 data = b;
 450         }
 451
 452         _writer->write (data);
 453 }