libhb/reader.c

   1 /* $Id: reader.c,v 1.21 2005/11/25 15:05:25 titer Exp $
   2
   3    This file is part of the HandBrake source code.
   4    Homepage: <http://handbrake.fr/>.
   5    It may be used under the terms of the GNU General Public License. */
   6
   7 #include "hb.h"
   8
   9 typedef struct
  10 {
  11     double average; // average time between packets
  12     int64_t last;   // last timestamp seen on this stream
  13     int id;         // stream id
  14     int is_audio;   // != 0 if this is an audio stream
  15 } stream_timing_t;
  16
  17 typedef struct
  18 {
  19     hb_job_t     * job;
  20     hb_title_t   * title;
  21     volatile int * die;
  22
  23     hb_dvd_t     * dvd;
  24     hb_stream_t  * stream;
  25
  26     stream_timing_t *stream_timing;
  27     int64_t        scr_offset;
  28     hb_psdemux_t   demux;
  29     int            scr_changes;
  30     uint32_t       sequence;
  31     uint8_t        st_slots;        // size (in slots) of stream_timing array
  32     uint8_t        saw_video;       // != 0 if we've seen video
  33     uint8_t        saw_audio;       // != 0 if we've seen audio
  34 } hb_reader_t;
  35
  36 /***********************************************************************
  37  * Local prototypes
  38  **********************************************************************/
  39 static void        ReaderFunc( void * );
  40 static hb_fifo_t ** GetFifoForId( hb_job_t * job, int id );
  41
  42 /***********************************************************************
  43  * hb_reader_init
  44  ***********************************************************************
  45  *
  46  **********************************************************************/
  47 hb_thread_t * hb_reader_init( hb_job_t * job )
  48 {
  49     hb_reader_t * r;
  50
  51     r = calloc( sizeof( hb_reader_t ), 1 );
  52
  53     r->job   = job;
  54     r->title = job->title;
  55     r->die   = job->die;
  56     r->sequence = 0;
  57
  58     r->st_slots = 4;
  59     r->stream_timing = calloc( sizeof(stream_timing_t), r->st_slots );
  60     r->stream_timing[0].id = r->title->video_id;
  61     r->stream_timing[0].average = 90000. * (double)job->vrate_base /
  62                                            (double)job->vrate;
  63     r->stream_timing[0].last = -r->stream_timing[0].average;
  64     r->stream_timing[1].id = -1;
  65
  66     return hb_thread_init( "reader", ReaderFunc, r,
  67                            HB_NORMAL_PRIORITY );
  68 }
  69
  70 static void push_buf( const hb_reader_t *r, hb_fifo_t *fifo, hb_buffer_t *buf )
  71 {
  72     hb_fifo_push_wait( fifo, buf );
  73 }
  74
  75 static int is_audio( hb_reader_t *r, int id )
  76 {
  77     int i;
  78     hb_audio_t *audio;
  79
  80     for( i = 0; ( audio = hb_list_item( r->title->list_audio, i ) ); ++i )
  81     {
  82         if ( audio->id == id )
  83         {
  84             return 1;
  85         }
  86     }
  87     return 0;
  88 }
  89
  90 // The MPEG STD (Standard Target Decoder) essentially requires that we keep
  91 // per-stream timing so that when there's a timing discontinuity we can
  92 // seemlessly join packets on either side of the discontinuity. This join
  93 // requires that we know the timestamp of the previous packet and the
  94 // average inter-packet time (since we position the new packet at the end
  95 // of the previous packet). The next four routines keep track of this
  96 // per-stream timing.
  97
  98 // find the per-stream timing state for 'buf'
  99
 100 static stream_timing_t *find_st( hb_reader_t *r, const hb_buffer_t *buf )
 101 {
 102     stream_timing_t *st = r->stream_timing;
 103     for ( ; st->id != -1; ++st )
 104     {
 105         if ( st->id == buf->id )
 106             return st;
 107     }
 108     return NULL;
 109 }
 110
 111 // find or create the per-stream timing state for 'buf'
 112
 113 static stream_timing_t *id_to_st( hb_reader_t *r, const hb_buffer_t *buf )
 114 {
 115     stream_timing_t *st = r->stream_timing;
 116     while ( st->id != buf->id && st->id != -1)
 117     {
 118         ++st;
 119     }
 120     // if we haven't seen this stream add it.
 121     if ( st->id == -1 )
 122     {
 123         // we keep the steam timing info in an array with some power-of-two
 124         // number of slots. If we don't have two slots left (one for our new
 125         // entry plus one for the "-1" eol) we need to expand the array.
 126         int slot = st - r->stream_timing;
 127         if ( slot + 1 >= r->st_slots )
 128         {
 129             r->st_slots *= 2;
 130             r->stream_timing = realloc( r->stream_timing, r->st_slots *
 131                                         sizeof(*r->stream_timing) );
 132             st = r->stream_timing + slot;
 133         }
 134         st->id = buf->id;
 135         st->average = 30.*90.;
 136         if ( r->saw_video )
 137             st->last = buf->renderOffset - st->average;
 138         else
 139             st->last = -st->average;
 140         if ( ( st->is_audio = is_audio( r, buf->id ) ) != 0 )
 141         {
 142             r->saw_audio = 1;
 143         }
 144         st[1].id = -1;
 145     }
 146     return st;
 147 }
 148
 149 // update the average inter-packet time of the stream associated with 'buf'
 150 // using a recursive low-pass filter with a 16 packet time constant.
 151
 152 static void update_ipt( hb_reader_t *r, const hb_buffer_t *buf )
 153 {
 154     stream_timing_t *st = id_to_st( r, buf );
 155     double dt = buf->renderOffset - st->last;
 156     st->average += ( dt - st->average ) * (1./32.);
 157     st->last = buf->renderOffset;
 158 }
 159
 160 // use the per-stream state associated with 'buf' to compute a new scr_offset
 161 // such that 'buf' will follow the previous packet of this stream separated
 162 // by the average packet time of the stream.
 163
 164 static void new_scr_offset( hb_reader_t *r, hb_buffer_t *buf )
 165 {
 166     stream_timing_t *st = id_to_st( r, buf );
 167     int64_t nxt = st->last + st->average;
 168     r->scr_offset = buf->renderOffset - nxt;
 169     buf->renderOffset = nxt;
 170     r->scr_changes = r->demux.scr_changes;
 171     st->last = buf->renderOffset;
 172 }
 173
 174 /***********************************************************************
 175  * ReaderFunc
 176  ***********************************************************************
 177  *
 178  **********************************************************************/
 179 static void ReaderFunc( void * _r )
 180 {
 181     hb_reader_t  * r = _r;
 182     hb_fifo_t   ** fifos;
 183     hb_buffer_t  * buf;
 184     hb_list_t    * list;
 185     int            n;
 186     int            chapter = -1;
 187     int            chapter_end = r->job->chapter_end;
 188
 189     if ( r->title->type == HB_DVD_TYPE )
 190     {
 191         if ( !( r->dvd = hb_dvd_init( r->title->path ) ) )
 192             return;
 193     }
 194     else if ( r->title->type == HB_STREAM_TYPE )
 195     {
 196         if ( !( r->stream = hb_stream_open( r->title->path, r->title ) ) )
 197             return;
 198     }
 199     else
 200     {
 201         // Unknown type, should never happen
 202         return;
 203     }
 204
 205     if (r->dvd)
 206     {
 207         /*
 208          * XXX this code is a temporary hack that should go away if/when
 209          *     chapter merging goes away in libhb/dvd.c
 210          * map the start and end chapter numbers to on-media chapter
 211          * numbers since chapter merging could cause the handbrake numbers
 212          * to diverge from the media numbers and, if our chapter_end is after
 213          * a media chapter that got merged, we'll stop ripping too early.
 214          */
 215         int start = r->job->chapter_start;
 216         hb_chapter_t *chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 217
 218         chapter_end = chap->index;
 219         if (start > 1)
 220         {
 221            chap = hb_list_item( r->title->list_chapter, start - 1 );
 222            start = chap->index;
 223         }
 224         /* end chapter mapping XXX */
 225
 226         if( !hb_dvd_start( r->dvd, r->title, start ) )
 227         {
 228             hb_dvd_close( &r->dvd );
 229             return;
 230         }
 231         if (r->job->angle)
 232         {
 233             hb_dvd_set_angle( r->dvd, r->job->angle );
 234         }
 235
 236         if ( r->job->start_at_preview )
 237         {
 238             // XXX code from DecodePreviews - should go into its own routine
 239             hb_dvd_seek( r->dvd, (float)r->job->start_at_preview /
 240                          ( r->job->seek_points ? ( r->job->seek_points + 1.0 ) : 11.0 ) );
 241         }
 242     }
 243     else if ( r->stream && r->job->start_at_preview )
 244     {
 245
 246         // XXX code from DecodePreviews - should go into its own routine
 247         hb_stream_seek( r->stream, (float)( r->job->start_at_preview - 1 ) /
 248                         ( r->job->seek_points ? ( r->job->seek_points + 1.0 ) : 11.0 ) );
 249
 250     }
 251     else if( r->stream )
 252     {
 253         /*
 254          * Standard stream, seek to the starting chapter, if set, and track the
 255          * end chapter so that we end at the right time.
 256          */
 257         int start = r->job->chapter_start;
 258         hb_chapter_t *chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 259
 260         chapter_end = chap->index;
 261         if (start > 1)
 262         {
 263             chap = hb_list_item( r->title->list_chapter, start - 1 );
 264             start = chap->index;
 265         }
 266
 267         /*
 268          * Seek to the start chapter.
 269          */
 270         hb_stream_seek_chapter( r->stream, start );
 271     }
 272
 273     list  = hb_list_init();
 274     hb_buffer_t *ps = hb_buffer_init( HB_DVD_READ_BUFFER_SIZE );
 275
 276     while( !*r->die && !r->job->done )
 277     {
 278         if (r->dvd)
 279             chapter = hb_dvd_chapter( r->dvd );
 280         else if (r->stream)
 281             chapter = hb_stream_chapter( r->stream );
 282
 283         if( chapter < 0 )
 284         {
 285             hb_log( "reader: end of the title reached" );
 286             break;
 287         }
 288         if( chapter > chapter_end )
 289         {
 290             hb_log( "reader: end of chapter %d (media %d) reached at media chapter %d",
 291                     r->job->chapter_end, chapter_end, chapter );
 292             break;
 293         }
 294
 295         if (r->dvd)
 296         {
 297           if( !hb_dvd_read( r->dvd, ps ) )
 298           {
 299               break;
 300           }
 301         }
 302         else if (r->stream)
 303         {
 304           if ( !hb_stream_read( r->stream, ps ) )
 305           {
 306             break;
 307           }
 308         }
 309
 310         if( r->job->indepth_scan )
 311         {
 312             /*
 313              * Need to update the progress during a subtitle scan
 314              */
 315             hb_state_t state;
 316
 317 #define p state.param.working
 318
 319             state.state = HB_STATE_WORKING;
 320             p.progress = (double)chapter / (double)r->job->chapter_end;
 321             if( p.progress > 1.0 )
 322             {
 323                 p.progress = 1.0;
 324             }
 325             p.rate_avg = 0.0;
 326             p.hours    = -1;
 327             p.minutes  = -1;
 328             p.seconds  = -1;
 329             hb_set_state( r->job->h, &state );
 330         }
 331
 332         (hb_demux[r->title->demuxer])( ps, list, &r->demux );
 333
 334         while( ( buf = hb_list_item( list, 0 ) ) )
 335         {
 336             hb_list_rem( list, buf );
 337             fifos = GetFifoForId( r->job, buf->id );
 338
 339             if ( fifos && ! r->saw_video )
 340             {
 341                 // The first data packet with a PTS from an audio or video stream
 342                 // that we're decoding defines 'time zero'. Discard packets until
 343                 // we get one.
 344                 if ( buf->start != -1 && buf->renderOffset != -1 &&
 345                      ( buf->id == r->title->video_id || is_audio( r, buf->id ) ) )
 346                 {
 347                     // force a new scr offset computation
 348                     r->scr_changes = r->demux.scr_changes - 1;
 349                     // create a stream state if we don't have one so the
 350                     // offset will get computed correctly.
 351                     id_to_st( r, buf );
 352                     r->saw_video = 1;
 353                     hb_log( "reader: first SCR %"PRId64" id %d DTS %"PRId64,
 354                             r->demux.last_scr, buf->id, buf->renderOffset );
 355                 }
 356                 else
 357                 {
 358                     fifos = NULL;
 359                 }
 360             }
 361             if( fifos )
 362             {
 363                 if ( buf->renderOffset != -1 )
 364                 {
 365                     if ( r->scr_changes == r->demux.scr_changes )
 366                     {
 367                         // This packet is referenced to the same SCR as the last.
 368                         // Adjust timestamp to remove the System Clock Reference
 369                         // offset then update the average inter-packet time
 370                         // for this stream.
 371                         buf->renderOffset -= r->scr_offset;
 372                         update_ipt( r, buf );
 373                     }
 374                     else
 375                     {
 376                         // This is the first audio or video packet after an SCR
 377                         // change. Compute a new scr offset that would make this
 378                         // packet follow the last of this stream with the correct
 379                         // average spacing.
 380                         stream_timing_t *st = find_st( r, buf );
 381
 382                         if ( st )
 383                         {
 384                             // if this is the video stream and we don't have
 385                             // audio yet or this is an audio stream
 386                             // generate a new scr
 387                             if ( st->is_audio ||
 388                                  ( st == r->stream_timing && !r->saw_audio ) )
 389                             {
 390                                 new_scr_offset( r, buf );
 391                             }
 392                             else
 393                             {
 394                                 // defer the scr change until we get some
 395                                 // audio since audio has a timestamp per
 396                                 // frame but video & subtitles don't. Clear
 397                                 // the timestamps so the decoder will generate
 398                                 // them from the frame durations.
 399                                 if ( st != r->stream_timing )
 400                                 {
 401                                     // not a video stream so it's probably
 402                                     // subtitles - the best we can do is to
 403                                     // line it up with the last video packet.
 404                                     buf->start = r->stream_timing->last;
 405                                 }
 406                                 else
 407                                 {
 408                                     buf->start = -1;
 409                                     buf->renderOffset = -1;
 410                                 }
 411                             }
 412                         }
 413                         else
 414                         {
 415                             // we got a new scr at the same time as the first
 416                             // packet of a stream we've never seen before. We
 417                             // have no idea what the timing should be so toss
 418                             // this buffer & wait for a stream we've already seen.
 419                             // add stream to list of streams we have seen
 420                             id_to_st( r, buf );
 421                             hb_buffer_close( &buf );
 422                             continue;
 423                         }
 424                     }
 425                 }
 426                 if ( buf->start != -1 )
 427                 {
 428                     buf->start -= r->scr_offset;
 429                     if ( r->job->pts_to_stop && buf->start > r->job->pts_to_stop )
 430                     {
 431                         // we're doing a subset of the input and we've hit the
 432                         // stopping point.
 433                         hb_buffer_close( &buf );
 434                         goto done;
 435                     }
 436                 }
 437
 438                 buf->sequence = r->sequence++;
 439                 /* if there are mutiple output fifos, send a copy of the
 440                  * buffer down all but the first (we have to not ship the
 441                  * original buffer or we'll race with the thread that's
 442                  * consuming the buffer & inject garbage into the data stream). */
 443                 for( n = 1; fifos[n] != NULL; n++)
 444                 {
 445                     hb_buffer_t *buf_copy = hb_buffer_init( buf->size );
 446                     hb_buffer_copy_settings( buf_copy, buf );
 447                     memcpy( buf_copy->data, buf->data, buf->size );
 448                     push_buf( r, fifos[n], buf_copy );
 449                 }
 450                 push_buf( r, fifos[0], buf );
 451             }
 452             else
 453             {
 454                 hb_buffer_close( &buf );
 455             }
 456         }
 457     }
 458
 459   done:
 460     // send empty buffers downstream to video & audio decoders to signal we're done.
 461     if( !*r->die && !r->job->done )
 462     {
 463         push_buf( r, r->job->fifo_mpeg2, hb_buffer_init(0) );
 464
 465         hb_audio_t *audio;
 466         for( n = 0; (audio = hb_list_item( r->job->title->list_audio, n)); ++n )
 467         {
 468             if ( audio->priv.fifo_in )
 469                 push_buf( r, audio->priv.fifo_in, hb_buffer_init(0) );
 470         }
 471
 472         hb_subtitle_t *subtitle;
 473         for( n = 0; (subtitle = hb_list_item( r->job->title->list_subtitle, n)); ++n )
 474         {
 475             if ( subtitle->fifo_in && subtitle->source == VOBSUB)
 476                 push_buf( r, subtitle->fifo_in, hb_buffer_init(0) );
 477         }
 478     }
 479
 480     hb_list_empty( &list );
 481     hb_buffer_close( &ps );
 482     if (r->dvd)
 483     {
 484         hb_dvd_stop( r->dvd );
 485         hb_dvd_close( &r->dvd );
 486     }
 487     else if (r->stream)
 488     {
 489         hb_stream_close(&r->stream);
 490     }
 491
 492     if ( r->stream_timing )
 493     {
 494         free( r->stream_timing );
 495     }
 496
 497     hb_log( "reader: done. %d scr changes", r->demux.scr_changes );
 498     if ( r->demux.dts_drops )
 499     {
 500         hb_log( "reader: %d drops because DTS out of range", r->demux.dts_drops );
 501     }
 502
 503     free( r );
 504     _r = NULL;
 505 }
 506
 507 /***********************************************************************
 508  * GetFifoForId
 509  ***********************************************************************
 510  *
 511  **********************************************************************/
 512 static hb_fifo_t ** GetFifoForId( hb_job_t * job, int id )
 513 {
 514     hb_title_t    * title = job->title;
 515     hb_audio_t    * audio;
 516     hb_subtitle_t * subtitle;
 517     int             i, n, count;
 518     static hb_fifo_t * fifos[100];
 519
 520     memset(fifos, 0, sizeof(fifos));
 521
 522     if( id == title->video_id )
 523     {
 524         if( job->indepth_scan )
 525         {
 526             /*
 527              * Ditch the video here during the indepth scan until
 528              * we can improve the MPEG2 decode performance.
 529              */
 530             return NULL;
 531         }
 532         else
 533         {
 534             fifos[0] = job->fifo_mpeg2;
 535             return fifos;
 536         }
 537     }
 538
 539     n = 0;
 540     count = hb_list_count( title->list_subtitle );
 541     count = count > 99 ? 99 : count;
 542     for( i=0; i < count; i++ ) {
 543         subtitle =  hb_list_item( title->list_subtitle, i );
 544         if (id == subtitle->id) {
 545             subtitle->hits++;
 546             if( !job->indepth_scan || job->select_subtitle_config.force )
 547             {
 548                 /*
 549                  * Pass the subtitles to be processed if we are not scanning, or if
 550                  * we are scanning and looking for forced subs, then pass them up
 551                  * to decode whether the sub is a forced one.
 552                  */
 553                 fifos[n++] = subtitle->fifo_in;
 554             }
 555         }
 556     }
 557     if ( n != 0 )
 558     {
 559         return fifos;
 560     }
 561
 562     if( !job->indepth_scan )
 563     {
 564         n = 0;
 565         for( i = 0; i < hb_list_count( title->list_audio ); i++ )
 566         {
 567             audio = hb_list_item( title->list_audio, i );
 568             if( id == audio->id )
 569             {
 570                 fifos[n++] = audio->priv.fifo_in;
 571             }
 572         }
 573
 574         if( n != 0 )
 575         {
 576             return fifos;
 577         }
 578     }
 579
 580     return NULL;
 581 }
 582