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     while( !*r->die && !r->job->done && hb_fifo_is_full( fifo ) )
  73     {
  74         /*
  75          * Loop until the incoming fifo is ready to receive
  76          * this buffer.
  77          */
  78         hb_snooze( 50 );
  79     }
  80     hb_fifo_push( fifo, buf );
  81 }
  82
  83 static int is_audio( hb_reader_t *r, int id )
  84 {
  85     int i;
  86     hb_audio_t *audio;
  87
  88     for( i = 0; ( audio = hb_list_item( r->title->list_audio, i ) ); ++i )
  89     {
  90         if ( audio->id == id )
  91         {
  92             return 1;
  93         }
  94     }
  95     return 0;
  96 }
  97
  98 // The MPEG STD (Standard Target Decoder) essentially requires that we keep
  99 // per-stream timing so that when there's a timing discontinuity we can
 100 // seemlessly join packets on either side of the discontinuity. This join
 101 // requires that we know the timestamp of the previous packet and the
 102 // average inter-packet time (since we position the new packet at the end
 103 // of the previous packet). The next four routines keep track of this
 104 // per-stream timing.
 105
 106 // find the per-stream timing state for 'buf'
 107
 108 static stream_timing_t *find_st( hb_reader_t *r, const hb_buffer_t *buf )
 109 {
 110     stream_timing_t *st = r->stream_timing;
 111     for ( ; st->id != -1; ++st )
 112     {
 113         if ( st->id == buf->id )
 114             return st;
 115     }
 116     return NULL;
 117 }
 118
 119 // find or create the per-stream timing state for 'buf'
 120
 121 static stream_timing_t *id_to_st( hb_reader_t *r, const hb_buffer_t *buf )
 122 {
 123     stream_timing_t *st = r->stream_timing;
 124     while ( st->id != buf->id && st->id != -1)
 125     {
 126         ++st;
 127     }
 128     // if we haven't seen this stream add it.
 129     if ( st->id == -1 )
 130     {
 131         // we keep the steam timing info in an array with some power-of-two
 132         // number of slots. If we don't have two slots left (one for our new
 133         // entry plus one for the "-1" eol) we need to expand the array.
 134         int slot = st - r->stream_timing;
 135         if ( slot + 1 >= r->st_slots )
 136         {
 137             r->st_slots *= 2;
 138             r->stream_timing = realloc( r->stream_timing, r->st_slots *
 139                                         sizeof(*r->stream_timing) );
 140             st = r->stream_timing + slot;
 141         }
 142         st->id = buf->id;
 143         st->average = 30.*90.;
 144         if ( r->saw_video )
 145             st->last = buf->renderOffset - st->average;
 146         else
 147             st->last = -st->average;
 148         if ( ( st->is_audio = is_audio( r, buf->id ) ) != 0 )
 149         {
 150             r->saw_audio = 1;
 151         }
 152         st[1].id = -1;
 153     }
 154     return st;
 155 }
 156
 157 // update the average inter-packet time of the stream associated with 'buf'
 158 // using a recursive low-pass filter with a 16 packet time constant.
 159
 160 static void update_ipt( hb_reader_t *r, const hb_buffer_t *buf )
 161 {
 162     stream_timing_t *st = id_to_st( r, buf );
 163     double dt = buf->renderOffset - st->last;
 164     st->average += ( dt - st->average ) * (1./32.);
 165     st->last = buf->renderOffset;
 166 }
 167
 168 // use the per-stream state associated with 'buf' to compute a new scr_offset
 169 // such that 'buf' will follow the previous packet of this stream separated
 170 // by the average packet time of the stream.
 171
 172 static void new_scr_offset( hb_reader_t *r, hb_buffer_t *buf )
 173 {
 174     stream_timing_t *st = id_to_st( r, buf );
 175     int64_t nxt = st->last + st->average;
 176     r->scr_offset = buf->renderOffset - nxt;
 177     buf->renderOffset = nxt;
 178     r->scr_changes = r->demux.scr_changes;
 179     st->last = buf->renderOffset;
 180 }
 181
 182 /***********************************************************************
 183  * ReaderFunc
 184  ***********************************************************************
 185  *
 186  **********************************************************************/
 187 static void ReaderFunc( void * _r )
 188 {
 189     hb_reader_t  * r = _r;
 190     hb_fifo_t   ** fifos;
 191     hb_buffer_t  * buf;
 192     hb_list_t    * list;
 193     int            n;
 194     int            chapter = -1;
 195     int            chapter_end = r->job->chapter_end;
 196
 197     if ( r->title->type == HB_DVD_TYPE )
 198     {
 199         if ( !( r->dvd = hb_dvd_init( r->title->path ) ) )
 200             return;
 201     }
 202     else if ( r->title->type == HB_STREAM_TYPE )
 203     {
 204         if ( !( r->stream = hb_stream_open( r->title->path, r->title ) ) )
 205             return;
 206     }
 207     else
 208     {
 209         // Unknown type, should never happen
 210         return;
 211     }
 212
 213     if (r->dvd)
 214     {
 215         /*
 216          * XXX this code is a temporary hack that should go away if/when
 217          *     chapter merging goes away in libhb/dvd.c
 218          * map the start and end chapter numbers to on-media chapter
 219          * numbers since chapter merging could cause the handbrake numbers
 220          * to diverge from the media numbers and, if our chapter_end is after
 221          * a media chapter that got merged, we'll stop ripping too early.
 222          */
 223         int start = r->job->chapter_start;
 224         hb_chapter_t *chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 225
 226         chapter_end = chap->index;
 227         if (start > 1)
 228         {
 229            chap = hb_list_item( r->title->list_chapter, start - 1 );
 230            start = chap->index;
 231         }
 232         /* end chapter mapping XXX */
 233
 234         if( !hb_dvd_start( r->dvd, r->title, start ) )
 235         {
 236             hb_dvd_close( &r->dvd );
 237             return;
 238         }
 239         if (r->job->angle)
 240         {
 241             hb_dvd_set_angle( r->dvd, r->job->angle );
 242         }
 243
 244         if ( r->job->start_at_preview )
 245         {
 246             // XXX code from DecodePreviews - should go into its own routine
 247             hb_dvd_seek( r->dvd, (float)r->job->start_at_preview /
 248                          ( r->job->seek_points ? ( r->job->seek_points + 1.0 ) : 11.0 ) );
 249         }
 250     }
 251     else if ( r->stream && r->job->start_at_preview )
 252     {
 253
 254         // XXX code from DecodePreviews - should go into its own routine
 255         hb_stream_seek( r->stream, (float)( r->job->start_at_preview - 1 ) /
 256                         ( r->job->seek_points ? ( r->job->seek_points + 1.0 ) : 11.0 ) );
 257
 258     }
 259     else if( r->stream )
 260     {
 261         /*
 262          * Standard stream, seek to the starting chapter, if set, and track the
 263          * end chapter so that we end at the right time.
 264          */
 265         int start = r->job->chapter_start;
 266         hb_chapter_t *chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 267
 268         chapter_end = chap->index;
 269         if (start > 1)
 270         {
 271             chap = hb_list_item( r->title->list_chapter, start - 1 );
 272             start = chap->index;
 273         }
 274
 275         /*
 276          * Seek to the start chapter.
 277          */
 278         hb_stream_seek_chapter( r->stream, start );
 279     }
 280
 281     list  = hb_list_init();
 282     hb_buffer_t *ps = hb_buffer_init( HB_DVD_READ_BUFFER_SIZE );
 283
 284     while( !*r->die && !r->job->done )
 285     {
 286         if (r->dvd)
 287             chapter = hb_dvd_chapter( r->dvd );
 288         else if (r->stream)
 289             chapter = hb_stream_chapter( r->stream );
 290
 291         if( chapter < 0 )
 292         {
 293             hb_log( "reader: end of the title reached" );
 294             break;
 295         }
 296         if( chapter > chapter_end )
 297         {
 298             hb_log( "reader: end of chapter %d (media %d) reached at media chapter %d",
 299                     r->job->chapter_end, chapter_end, chapter );
 300             break;
 301         }
 302
 303         if (r->dvd)
 304         {
 305           if( !hb_dvd_read( r->dvd, ps ) )
 306           {
 307               break;
 308           }
 309         }
 310         else if (r->stream)
 311         {
 312           if ( !hb_stream_read( r->stream, ps ) )
 313           {
 314             break;
 315           }
 316         }
 317
 318         if( r->job->indepth_scan )
 319         {
 320             /*
 321              * Need to update the progress during a subtitle scan
 322              */
 323             hb_state_t state;
 324
 325 #define p state.param.working
 326
 327             state.state = HB_STATE_WORKING;
 328             p.progress = (double)chapter / (double)r->job->chapter_end;
 329             if( p.progress > 1.0 )
 330             {
 331                 p.progress = 1.0;
 332             }
 333             p.rate_avg = 0.0;
 334             p.hours    = -1;
 335             p.minutes  = -1;
 336             p.seconds  = -1;
 337             hb_set_state( r->job->h, &state );
 338         }
 339
 340         (hb_demux[r->title->demuxer])( ps, list, &r->demux );
 341
 342         while( ( buf = hb_list_item( list, 0 ) ) )
 343         {
 344             hb_list_rem( list, buf );
 345             fifos = GetFifoForId( r->job, buf->id );
 346
 347             if ( fifos && ! r->saw_video )
 348             {
 349                 // The first data packet with a PTS from an audio or video stream
 350                 // that we're decoding defines 'time zero'. Discard packets until
 351                 // we get one.
 352                 if ( buf->start != -1 && buf->renderOffset != -1 &&
 353                      ( buf->id == r->title->video_id || is_audio( r, buf->id ) ) )
 354                 {
 355                     // force a new scr offset computation
 356                     r->scr_changes = r->demux.scr_changes - 1;
 357                     // create a stream state if we don't have one so the
 358                     // offset will get computed correctly.
 359                     id_to_st( r, buf );
 360                     r->saw_video = 1;
 361                     hb_log( "reader: first SCR %"PRId64" id %d DTS %"PRId64,
 362                             r->demux.last_scr, buf->id, buf->renderOffset );
 363                 }
 364                 else
 365                 {
 366                     fifos = NULL;
 367                 }
 368             }
 369             if( fifos )
 370             {
 371                 if ( buf->renderOffset != -1 )
 372                 {
 373                     if ( r->scr_changes == r->demux.scr_changes )
 374                     {
 375                         // This packet is referenced to the same SCR as the last.
 376                         // Adjust timestamp to remove the System Clock Reference
 377                         // offset then update the average inter-packet time
 378                         // for this stream.
 379                         buf->renderOffset -= r->scr_offset;
 380                         update_ipt( r, buf );
 381                     }
 382                     else
 383                     {
 384                         // This is the first audio or video packet after an SCR
 385                         // change. Compute a new scr offset that would make this
 386                         // packet follow the last of this stream with the correct
 387                         // average spacing.
 388                         stream_timing_t *st = find_st( r, buf );
 389
 390                         if ( st )
 391                         {
 392                             // if this is the video stream and we don't have
 393                             // audio yet or this is an audio stream
 394                             // generate a new scr
 395                             if ( st->is_audio ||
 396                                  ( st == r->stream_timing && !r->saw_audio ) )
 397                             {
 398                                 new_scr_offset( r, buf );
 399                             }
 400                             else
 401                             {
 402                                 // defer the scr change until we get some
 403                                 // audio since audio has a timestamp per
 404                                 // frame but video & subtitles don't. Clear
 405                                 // the timestamps so the decoder will generate
 406                                 // them from the frame durations.
 407                                 if ( st != r->stream_timing )
 408                                 {
 409                                     // not a video stream so it's probably
 410                                     // subtitles - the best we can do is to
 411                                     // line it up with the last video packet.
 412                                     buf->start = r->stream_timing->last;
 413                                 }
 414                                 else
 415                                 {
 416                                     buf->start = -1;
 417                                     buf->renderOffset = -1;
 418                                 }
 419                             }
 420                         }
 421                         else
 422                         {
 423                             // we got a new scr at the same time as the first
 424                             // packet of a stream we've never seen before. We
 425                             // have no idea what the timing should be so toss
 426                             // this buffer & wait for a stream we've already seen.
 427                             // add stream to list of streams we have seen
 428                             id_to_st( r, buf );
 429                             hb_buffer_close( &buf );
 430                             continue;
 431                         }
 432                     }
 433                 }
 434                 if ( buf->start != -1 )
 435                 {
 436                     buf->start -= r->scr_offset;
 437                     if ( r->job->pts_to_stop && buf->start > r->job->pts_to_stop )
 438                     {
 439                         // we're doing a subset of the input and we've hit the
 440                         // stopping point.
 441                         hb_buffer_close( &buf );
 442                         goto done;
 443                     }
 444                 }
 445
 446                 buf->sequence = r->sequence++;
 447                 /* if there are mutiple output fifos, send a copy of the
 448                  * buffer down all but the first (we have to not ship the
 449                  * original buffer or we'll race with the thread that's
 450                  * consuming the buffer & inject garbage into the data stream). */
 451                 for( n = 1; fifos[n] != NULL; n++)
 452                 {
 453                     hb_buffer_t *buf_copy = hb_buffer_init( buf->size );
 454                     hb_buffer_copy_settings( buf_copy, buf );
 455                     memcpy( buf_copy->data, buf->data, buf->size );
 456                     push_buf( r, fifos[n], buf_copy );
 457                 }
 458                 push_buf( r, fifos[0], buf );
 459             }
 460             else
 461             {
 462                 hb_buffer_close( &buf );
 463             }
 464         }
 465     }
 466
 467   done:
 468     // send empty buffers downstream to video & audio decoders to signal we're done.
 469     push_buf( r, r->job->fifo_mpeg2, hb_buffer_init(0) );
 470
 471     hb_audio_t *audio;
 472     for( n = 0; ( audio = hb_list_item( r->job->title->list_audio, n ) ); ++n )
 473     {
 474         if ( audio->priv.fifo_in )
 475             push_buf( r, audio->priv.fifo_in, hb_buffer_init(0) );
 476     }
 477
 478     hb_subtitle_t *subtitle;
 479     for( n = 0; ( subtitle = hb_list_item( r->job->title->list_subtitle, n ) ); ++n )
 480     {
 481         if ( subtitle->fifo_in && subtitle->source == VOBSUB)
 482             push_buf( r, subtitle->fifo_in, hb_buffer_init(0) );
 483     }
 484
 485     hb_list_empty( &list );
 486     hb_buffer_close( &ps );
 487     if (r->dvd)
 488     {
 489         hb_dvd_stop( r->dvd );
 490         hb_dvd_close( &r->dvd );
 491     }
 492     else if (r->stream)
 493     {
 494         hb_stream_close(&r->stream);
 495     }
 496
 497     if ( r->stream_timing )
 498     {
 499         free( r->stream_timing );
 500     }
 501
 502     hb_log( "reader: done. %d scr changes", r->demux.scr_changes );
 503     if ( r->demux.dts_drops )
 504     {
 505         hb_log( "reader: %d drops because DTS out of range", r->demux.dts_drops );
 506     }
 507
 508     free( r );
 509     _r = NULL;
 510 }
 511
 512 /***********************************************************************
 513  * GetFifoForId
 514  ***********************************************************************
 515  *
 516  **********************************************************************/
 517 static hb_fifo_t ** GetFifoForId( hb_job_t * job, int id )
 518 {
 519     hb_title_t    * title = job->title;
 520     hb_audio_t    * audio;
 521     hb_subtitle_t * subtitle;
 522     int             i, n, count;
 523     static hb_fifo_t * fifos[100];
 524
 525     memset(fifos, 0, sizeof(fifos));
 526
 527     if( id == title->video_id )
 528     {
 529         if( job->indepth_scan )
 530         {
 531             /*
 532              * Ditch the video here during the indepth scan until
 533              * we can improve the MPEG2 decode performance.
 534              */
 535             return NULL;
 536         }
 537         else
 538         {
 539             fifos[0] = job->fifo_mpeg2;
 540             return fifos;
 541         }
 542     }
 543
 544     n = 0;
 545     count = hb_list_count( title->list_subtitle );
 546     count = count > 99 ? 99 : count;
 547     for( i=0; i < count; i++ ) {
 548         subtitle =  hb_list_item( title->list_subtitle, i );
 549         if (id == subtitle->id) {
 550             subtitle->hits++;
 551             if( !job->indepth_scan || job->select_subtitle_config.force )
 552             {
 553                 /*
 554                  * Pass the subtitles to be processed if we are not scanning, or if
 555                  * we are scanning and looking for forced subs, then pass them up
 556                  * to decode whether the sub is a forced one.
 557                  */
 558                 fifos[n++] = subtitle->fifo_in;
 559             }
 560         }
 561     }
 562     if ( n != 0 )
 563     {
 564         return fifos;
 565     }
 566
 567     if( !job->indepth_scan )
 568     {
 569         n = 0;
 570         for( i = 0; i < hb_list_count( title->list_audio ); i++ )
 571         {
 572             audio = hb_list_item( title->list_audio, i );
 573             if( id == audio->id )
 574             {
 575                 fifos[n++] = audio->priv.fifo_in;
 576             }
 577         }
 578
 579         if( n != 0 )
 580         {
 581             return fifos;
 582         }
 583     }
 584
 585     return NULL;
 586 }
 587