src/lib/player.cc

   1 /* -*- c-basic-offset: 8; default-tab-width: 8; -*- */
   2
   3 /*
   4     Copyright (C) 2013 Carl Hetherington <cth@carlh.net>
   5
   6     This program 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     This program 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 this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20 */
  21
  22 #include "player.h"
  23 #include "film.h"
  24 #include "ffmpeg_decoder.h"
  25 #include "ffmpeg_content.h"
  26 #include "imagemagick_decoder.h"
  27 #include "imagemagick_content.h"
  28 #include "sndfile_decoder.h"
  29 #include "sndfile_content.h"
  30 #include "playlist.h"
  31 #include "job.h"
  32 #include "image.h"
  33 #include "null_content.h"
  34 #include "black_decoder.h"
  35 #include "silence_decoder.h"
  36
  37 using std::list;
  38 using std::cout;
  39 using std::min;
  40 using std::vector;
  41 using boost::shared_ptr;
  42 using boost::weak_ptr;
  43 using boost::dynamic_pointer_cast;
  44
  45 struct Piece
  46 {
  47         Piece (shared_ptr<Content> c, shared_ptr<Decoder> d)
  48                 : content (c)
  49                 , decoder (d)
  50         {}
  51
  52         shared_ptr<Content> content;
  53         shared_ptr<Decoder> decoder;
  54 };
  55
  56 Player::Player (shared_ptr<const Film> f, shared_ptr<const Playlist> p)
  57         : _film (f)
  58         , _playlist (p)
  59         , _video (true)
  60         , _audio (true)
  61         , _subtitles (true)
  62         , _have_valid_pieces (false)
  63         , _position (0)
  64         , _audio_buffers (MAX_AUDIO_CHANNELS, 0)
  65         , _next_audio (0)
  66 {
  67         _playlist->Changed.connect (bind (&Player::playlist_changed, this));
  68         _playlist->ContentChanged.connect (bind (&Player::content_changed, this, _1, _2));
  69 }
  70
  71 void
  72 Player::disable_video ()
  73 {
  74         _video = false;
  75 }
  76
  77 void
  78 Player::disable_audio ()
  79 {
  80         _audio = false;
  81 }
  82
  83 void
  84 Player::disable_subtitles ()
  85 {
  86         _subtitles = false;
  87 }
  88
  89 bool
  90 Player::pass ()
  91 {
  92         if (!_have_valid_pieces) {
  93                 setup_pieces ();
  94                 _have_valid_pieces = true;
  95         }
  96
  97         /* Here we are just finding the active decoder with the earliest last emission time, then
  98            calling pass on it.
  99         */
 100
 101         Time earliest_t = TIME_MAX;
 102         shared_ptr<Piece> earliest;
 103
 104         for (list<shared_ptr<Piece> >::iterator i = _pieces.begin(); i != _pieces.end(); ++i) {
 105                 if ((*i)->content->end() < _position) {
 106                         continue;
 107                 }
 108
 109                 Time const t = (*i)->content->start() + (*i)->decoder->next();
 110                 if (t < earliest_t) {
 111                         earliest_t = t;
 112                         earliest = *i;
 113                 }
 114         }
 115
 116         if (!earliest) {
 117                 return true;
 118         }
 119
 120         earliest->decoder->pass ();
 121
 122         /* Move position to earliest active next emission */
 123
 124         for (list<shared_ptr<Piece> >::iterator i = _pieces.begin(); i != _pieces.end(); ++i) {
 125                 if ((*i)->content->end() < _position) {
 126                         continue;
 127                 }
 128
 129                 Time const t = (*i)->content->start() + (*i)->decoder->next();
 130
 131                 if (t < _position) {
 132                         _position = t;
 133                 }
 134         }
 135
 136         return false;
 137 }
 138
 139 void
 140 Player::process_video (weak_ptr<Content> weak_content, shared_ptr<const Image> image, bool same, shared_ptr<Subtitle> sub, Time time)
 141 {
 142         shared_ptr<Content> content = weak_content.lock ();
 143         if (!content) {
 144                 return;
 145         }
 146
 147         time += content->start ();
 148
 149         Video (image, same, sub, time);
 150 }
 151
 152 void
 153 Player::process_audio (weak_ptr<Content> weak_content, shared_ptr<const AudioBuffers> audio, Time time)
 154 {
 155         shared_ptr<Content> content = weak_content.lock ();
 156         if (!content) {
 157                 return;
 158         }
 159
 160         /* XXX: mapping */
 161
 162         /* The time of this audio may indicate that some of our buffered audio is not going to
 163            be added to any more, so it can be emitted.
 164         */
 165
 166         time += content->start ();
 167
 168         if (time > _next_audio) {
 169                 /* We can emit some audio from our buffers */
 170                 OutputAudioFrame const N = min (_film->time_to_audio_frames (time - _next_audio), static_cast<OutputAudioFrame> (_audio_buffers.frames()));
 171                 shared_ptr<AudioBuffers> emit (new AudioBuffers (_audio_buffers.channels(), N));
 172                 emit->copy_from (&_audio_buffers, N, 0, 0);
 173                 Audio (emit, _next_audio);
 174                 _next_audio += _film->audio_frames_to_time (N);
 175
 176                 /* And remove it from our buffers */
 177                 if (_audio_buffers.frames() > N) {
 178                         _audio_buffers.move (N, 0, _audio_buffers.frames() - N);
 179                 }
 180                 _audio_buffers.set_frames (_audio_buffers.frames() - N);
 181         }
 182
 183         /* Now accumulate the new audio into our buffers */
 184         _audio_buffers.ensure_size (time - _next_audio + audio->frames());
 185         _audio_buffers.accumulate (audio.get(), 0, _film->time_to_audio_frames (time - _next_audio));
 186 }
 187
 188 /** @return true on error */
 189 void
 190 Player::seek (Time t)
 191 {
 192         if (!_have_valid_pieces) {
 193                 setup_pieces ();
 194                 _have_valid_pieces = true;
 195         }
 196
 197         if (_pieces.empty ()) {
 198                 return;
 199         }
 200
 201         for (list<shared_ptr<Piece> >::iterator i = _pieces.begin(); i != _pieces.end(); ++i) {
 202                 if ((*i)->content->end() < t) {
 203                         continue;
 204                 }
 205
 206                 (*i)->decoder->seek (t);
 207         }
 208
 209         _position = t;
 210
 211         /* XXX: don't seek audio because we don't need to... */
 212 }
 213
 214
 215 void
 216 Player::seek_back ()
 217 {
 218         /* XXX */
 219 }
 220
 221 void
 222 Player::seek_forward ()
 223 {
 224         /* XXX */
 225 }
 226
 227 struct ContentSorter
 228 {
 229         bool operator() (shared_ptr<Content> a, shared_ptr<Content> b)
 230         {
 231                 return a->start() < b->start();
 232         }
 233 };
 234
 235 void
 236 Player::setup_pieces ()
 237 {
 238         list<shared_ptr<Piece> > old_pieces = _pieces;
 239
 240         _pieces.clear ();
 241
 242         Playlist::ContentList content = _playlist->content ();
 243         sort (content.begin(), content.end(), ContentSorter ());
 244
 245         for (Playlist::ContentList::iterator i = content.begin(); i != content.end(); ++i) {
 246
 247                 shared_ptr<Decoder> decoder;
 248
 249                 /* XXX: into content? */
 250
 251                 shared_ptr<const FFmpegContent> fc = dynamic_pointer_cast<const FFmpegContent> (*i);
 252                 if (fc) {
 253                         shared_ptr<FFmpegDecoder> fd (new FFmpegDecoder (_film, fc, _video, _audio, _subtitles));
 254
 255                         fd->Video.connect (bind (&Player::process_video, this, *i, _1, _2, _3, _4));
 256                         fd->Audio.connect (bind (&Player::process_audio, this, *i, _1, _2));
 257
 258                         decoder = fd;
 259                 }
 260
 261                 shared_ptr<const ImageMagickContent> ic = dynamic_pointer_cast<const ImageMagickContent> (*i);
 262                 if (ic) {
 263                         shared_ptr<ImageMagickDecoder> id;
 264
 265                         /* See if we can re-use an old ImageMagickDecoder */
 266                         for (list<shared_ptr<Piece> >::const_iterator j = old_pieces.begin(); j != old_pieces.end(); ++j) {
 267                                 shared_ptr<ImageMagickDecoder> imd = dynamic_pointer_cast<ImageMagickDecoder> ((*j)->decoder);
 268                                 if (imd && imd->content() == ic) {
 269                                         id = imd;
 270                                 }
 271                         }
 272
 273                         if (!id) {
 274                                 id.reset (new ImageMagickDecoder (_film, ic));
 275                                 id->Video.connect (bind (&Player::process_video, this, *i, _1, _2, _3, _4));
 276                         }
 277
 278                         decoder = id;
 279                 }
 280
 281                 shared_ptr<const SndfileContent> sc = dynamic_pointer_cast<const SndfileContent> (*i);
 282                 if (sc) {
 283                         shared_ptr<AudioDecoder> sd (new SndfileDecoder (_film, sc));
 284                         sd->Audio.connect (bind (&Player::process_audio, this, *i, _1, _2));
 285
 286                         decoder = sd;
 287                 }
 288
 289                 _pieces.push_back (shared_ptr<Piece> (new Piece (*i, decoder)));
 290         }
 291
 292         /* Fill in visual gaps with black and audio gaps with silence */
 293
 294         Time video_pos = 0;
 295         Time audio_pos = 0;
 296         list<shared_ptr<Piece> > pieces_copy = _pieces;
 297         for (list<shared_ptr<Piece> >::iterator i = pieces_copy.begin(); i != pieces_copy.end(); ++i) {
 298                 if (dynamic_pointer_cast<VideoContent> ((*i)->content)) {
 299                         Time const diff = video_pos - (*i)->content->start();
 300                         if (diff > 0) {
 301                                 shared_ptr<NullContent> nc (new NullContent (_film, video_pos, diff));
 302                                 _pieces.push_back (shared_ptr<Piece> (new Piece (nc, shared_ptr<Decoder> (new BlackDecoder (_film, nc)))));
 303                         }
 304
 305                         video_pos = (*i)->content->end();
 306                 } else {
 307                         Time const diff = audio_pos - (*i)->content->start();
 308                         if (diff > 0) {
 309                                 shared_ptr<NullContent> nc (new NullContent (_film, audio_pos, diff));
 310                                 _pieces.push_back (shared_ptr<Piece> (new Piece (nc, shared_ptr<Decoder> (new SilenceDecoder (_film, nc)))));
 311                         }
 312                         audio_pos = (*i)->content->end();
 313                 }
 314         }
 315
 316         _position = 0;
 317 }
 318
 319 void
 320 Player::content_changed (weak_ptr<Content> w, int p)
 321 {
 322         shared_ptr<Content> c = w.lock ();
 323         if (!c) {
 324                 return;
 325         }
 326
 327         if (p == VideoContentProperty::VIDEO_LENGTH) {
 328                 _have_valid_pieces = false;
 329         }
 330 }
 331
 332 void
 333 Player::playlist_changed ()
 334 {
 335         _have_valid_pieces = false;
 336 }