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 )
  73     {
  74         if ( hb_fifo_full_wait( fifo ) )
  75         {
  76             hb_fifo_push( fifo, buf );
  77             break;
  78         }
  79     }
  80 }
  81
  82 static int is_audio( hb_reader_t *r, int id )
  83 {
  84     int i;
  85     hb_audio_t *audio;
  86
  87     for( i = 0; ( audio = hb_list_item( r->title->list_audio, i ) ); ++i )
  88     {
  89         if ( audio->id == id )
  90         {
  91             return 1;
  92         }
  93     }
  94     return 0;
  95 }
  96
  97 // The MPEG STD (Standard Target Decoder) essentially requires that we keep
  98 // per-stream timing so that when there's a timing discontinuity we can
  99 // seemlessly join packets on either side of the discontinuity. This join
 100 // requires that we know the timestamp of the previous packet and the
 101 // average inter-packet time (since we position the new packet at the end
 102 // of the previous packet). The next four routines keep track of this
 103 // per-stream timing.
 104
 105 // find the per-stream timing state for 'buf'
 106
 107 static stream_timing_t *find_st( hb_reader_t *r, const hb_buffer_t *buf )
 108 {
 109     stream_timing_t *st = r->stream_timing;
 110     for ( ; st->id != -1; ++st )
 111     {
 112         if ( st->id == buf->id )
 113             return st;
 114     }
 115     return NULL;
 116 }
 117
 118 // find or create the per-stream timing state for 'buf'
 119
 120 static stream_timing_t *id_to_st( hb_reader_t *r, const hb_buffer_t *buf )
 121 {
 122     stream_timing_t *st = r->stream_timing;
 123     while ( st->id != buf->id && st->id != -1)
 124     {
 125         ++st;
 126     }
 127     // if we haven't seen this stream add it.
 128     if ( st->id == -1 )
 129     {
 130         // we keep the steam timing info in an array with some power-of-two
 131         // number of slots. If we don't have two slots left (one for our new
 132         // entry plus one for the "-1" eol) we need to expand the array.
 133         int slot = st - r->stream_timing;
 134         if ( slot + 1 >= r->st_slots )
 135         {
 136             r->st_slots *= 2;
 137             r->stream_timing = realloc( r->stream_timing, r->st_slots *
 138                                         sizeof(*r->stream_timing) );
 139             st = r->stream_timing + slot;
 140         }
 141         st->id = buf->id;
 142         st->average = 30.*90.;
 143         if ( r->saw_video )
 144             st->last = buf->renderOffset - st->average;
 145         else
 146             st->last = -st->average;
 147         if ( ( st->is_audio = is_audio( r, buf->id ) ) != 0 )
 148         {
 149             r->saw_audio = 1;
 150         }
 151         st[1].id = -1;
 152     }
 153     return st;
 154 }
 155
 156 // update the average inter-packet time of the stream associated with 'buf'
 157 // using a recursive low-pass filter with a 16 packet time constant.
 158
 159 static void update_ipt( hb_reader_t *r, const hb_buffer_t *buf )
 160 {
 161     stream_timing_t *st = id_to_st( r, buf );
 162     double dt = buf->renderOffset - st->last;
 163     st->average += ( dt - st->average ) * (1./32.);
 164     st->last = buf->renderOffset;
 165 }
 166
 167 // use the per-stream state associated with 'buf' to compute a new scr_offset
 168 // such that 'buf' will follow the previous packet of this stream separated
 169 // by the average packet time of the stream.
 170
 171 static void new_scr_offset( hb_reader_t *r, hb_buffer_t *buf )
 172 {
 173     stream_timing_t *st = id_to_st( r, buf );
 174     int64_t nxt = st->last + st->average;
 175     r->scr_offset = buf->renderOffset - nxt;
 176     buf->renderOffset = nxt;
 177     r->scr_changes = r->demux.scr_changes;
 178     st->last = buf->renderOffset;
 179 }
 180
 181 /***********************************************************************
 182  * ReaderFunc
 183  ***********************************************************************
 184  *
 185  **********************************************************************/
 186 static void ReaderFunc( void * _r )
 187 {
 188     hb_reader_t  * r = _r;
 189     hb_fifo_t   ** fifos;
 190     hb_buffer_t  * buf;
 191     hb_list_t    * list;
 192     int            n;
 193     int            chapter = -1;
 194     int            chapter_end = r->job->chapter_end;
 195
 196     if ( r->title->type == HB_DVD_TYPE )
 197     {
 198         if ( !( r->dvd = hb_dvd_init( r->title->path ) ) )
 199             return;
 200     }
 201     else if ( r->title->type == HB_STREAM_TYPE )
 202     {
 203         if ( !( r->stream = hb_stream_open( r->title->path, r->title ) ) )
 204             return;
 205     }
 206     else
 207     {
 208         // Unknown type, should never happen
 209         return;
 210     }
 211
 212     if (r->dvd)
 213     {
 214         /*
 215          * XXX this code is a temporary hack that should go away if/when
 216          *     chapter merging goes away in libhb/dvd.c
 217          * map the start and end chapter numbers to on-media chapter
 218          * numbers since chapter merging could cause the handbrake numbers
 219          * to diverge from the media numbers and, if our chapter_end is after
 220          * a media chapter that got merged, we'll stop ripping too early.
 221          */
 222         int start = r->job->chapter_start;
 223         hb_chapter_t *chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 224
 225         chapter_end = chap->index;
 226         if (start > 1)
 227         {
 228            chap = hb_list_item( r->title->list_chapter, start - 1 );
 229            start = chap->index;
 230         }
 231         /* end chapter mapping XXX */
 232
 233         if( !hb_dvd_start( r->dvd, r->title, start ) )
 234         {
 235             hb_dvd_close( &r->dvd );
 236             return;
 237         }
 238         if (r->job->angle)
 239         {
 240             hb_dvd_set_angle( r->dvd, r->job->angle );
 241         }
 242
 243         if ( r->job->start_at_preview )
 244         {
 245             // XXX code from DecodePreviews - should go into its own routine
 246             hb_dvd_seek( r->dvd, (float)r->job->start_at_preview /
 247                          ( r->job->seek_points ? ( r->job->seek_points + 1.0 ) : 11.0 ) );
 248         }
 249     }
 250     else if ( r->stream && r->job->start_at_preview )
 251     {
 252
 253         // XXX code from DecodePreviews - should go into its own routine
 254         hb_stream_seek( r->stream, (float)( r->job->start_at_preview - 1 ) /
 255                         ( r->job->seek_points ? ( r->job->seek_points + 1.0 ) : 11.0 ) );
 256
 257     }
 258     else if( r->stream )
 259     {
 260         /*
 261          * Standard stream, seek to the starting chapter, if set, and track the
 262          * end chapter so that we end at the right time.
 263          */
 264         int start = r->job->chapter_start;
 265         hb_chapter_t *chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 266
 267         chapter_end = chap->index;
 268         if (start > 1)
 269         {
 270             chap = hb_list_item( r->title->list_chapter, start - 1 );
 271             start = chap->index;
 272         }
 273
 274         /*
 275          * Seek to the start chapter.
 276          */
 277         hb_stream_seek_chapter( r->stream, start );
 278     }
 279
 280     list  = hb_list_init();
 281     hb_buffer_t *ps = hb_buffer_init( HB_DVD_READ_BUFFER_SIZE );
 282
 283     while( !*r->die && !r->job->done )
 284     {
 285         if (r->dvd)
 286             chapter = hb_dvd_chapter( r->dvd );
 287         else if (r->stream)
 288             chapter = hb_stream_chapter( r->stream );
 289
 290         if( chapter < 0 )
 291         {
 292             hb_log( "reader: end of the title reached" );
 293             break;
 294         }
 295         if( chapter > chapter_end )
 296         {
 297             hb_log( "reader: end of chapter %d (media %d) reached at media chapter %d",
 298                     r->job->chapter_end, chapter_end, chapter );
 299             break;
 300         }
 301
 302         if (r->dvd)
 303         {
 304           if( !hb_dvd_read( r->dvd, ps ) )
 305           {
 306               break;
 307           }
 308         }
 309         else if (r->stream)
 310         {
 311           if ( !hb_stream_read( r->stream, ps ) )
 312           {
 313             break;
 314           }
 315         }
 316
 317         if( r->job->indepth_scan )
 318         {
 319             /*
 320              * Need to update the progress during a subtitle scan
 321              */
 322             hb_state_t state;
 323
 324 #define p state.param.working
 325
 326             state.state = HB_STATE_WORKING;
 327             p.progress = (double)chapter / (double)r->job->chapter_end;
 328             if( p.progress > 1.0 )
 329             {
 330                 p.progress = 1.0;
 331             }
 332             p.rate_avg = 0.0;
 333             p.hours    = -1;
 334             p.minutes  = -1;
 335             p.seconds  = -1;
 336             hb_set_state( r->job->h, &state );
 337         }
 338
 339         (hb_demux[r->title->demuxer])( ps, list, &r->demux );
 340
 341         while( ( buf = hb_list_item( list, 0 ) ) )
 342         {
 343             hb_list_rem( list, buf );
 344             fifos = GetFifoForId( r->job, buf->id );
 345
 346             if ( fifos && ! r->saw_video && !r->job->indepth_scan )
 347             {
 348                 // The first data packet with a PTS from an audio or video stream
 349                 // that we're decoding defines 'time zero'. Discard packets until
 350                 // we get one.
 351                 if ( buf->start != -1 && buf->renderOffset != -1 &&
 352                      ( buf->id == r->title->video_id || is_audio( r, buf->id ) ) )
 353                 {
 354                     // force a new scr offset computation
 355                     r->scr_changes = r->demux.scr_changes - 1;
 356                     // create a stream state if we don't have one so the
 357                     // offset will get computed correctly.
 358                     id_to_st( r, buf );
 359                     r->saw_video = 1;
 360                     hb_log( "reader: first SCR %"PRId64" id %d DTS %"PRId64,
 361                             r->demux.last_scr, buf->id, buf->renderOffset );
 362                 }
 363                 else
 364                 {
 365                     fifos = NULL;
 366                 }
 367             }
 368             if( fifos )
 369             {
 370                 if ( buf->renderOffset != -1 )
 371                 {
 372                     if ( r->scr_changes == r->demux.scr_changes )
 373                     {
 374                         // This packet is referenced to the same SCR as the last.
 375                         // Adjust timestamp to remove the System Clock Reference
 376                         // offset then update the average inter-packet time
 377                         // for this stream.
 378                         buf->renderOffset -= r->scr_offset;
 379                         update_ipt( r, buf );
 380                     }
 381                     else
 382                     {
 383                         // This is the first audio or video packet after an SCR
 384                         // change. Compute a new scr offset that would make this
 385                         // packet follow the last of this stream with the correct
 386                         // average spacing.
 387                         stream_timing_t *st = find_st( r, buf );
 388
 389                         if ( st )
 390                         {
 391                             // if this is the video stream and we don't have
 392                             // audio yet or this is an audio stream
 393                             // generate a new scr
 394                             if ( st->is_audio ||
 395                                  ( st == r->stream_timing && !r->saw_audio ) )
 396                             {
 397                                 new_scr_offset( r, buf );
 398                             }
 399                             else
 400                             {
 401                                 // defer the scr change until we get some
 402                                 // audio since audio has a timestamp per
 403                                 // frame but video & subtitles don't. Clear
 404                                 // the timestamps so the decoder will generate
 405                                 // them from the frame durations.
 406                                 if ( st != r->stream_timing )
 407                                 {
 408                                     // not a video stream so it's probably
 409                                     // subtitles - the best we can do is to
 410                                     // line it up with the last video packet.
 411                                     buf->start = r->stream_timing->last;
 412                                 }
 413                                 else
 414                                 {
 415                                     buf->start = -1;
 416                                     buf->renderOffset = -1;
 417                                 }
 418                             }
 419                         }
 420                         else
 421                         {
 422                             // we got a new scr at the same time as the first
 423                             // packet of a stream we've never seen before. We
 424                             // have no idea what the timing should be so toss
 425                             // this buffer & wait for a stream we've already seen.
 426                             // add stream to list of streams we have seen
 427                             id_to_st( r, buf );
 428                             hb_buffer_close( &buf );
 429                             continue;
 430                         }
 431                     }
 432                 }
 433                 if ( buf->start != -1 )
 434                 {
 435                     buf->start -= r->scr_offset;
 436                     if ( r->job->pts_to_stop && buf->start > r->job->pts_to_stop )
 437                     {
 438                         // we're doing a subset of the input and we've hit the
 439                         // stopping point.
 440                         hb_buffer_close( &buf );
 441                         goto done;
 442                     }
 443                 }
 444
 445                 buf->sequence = r->sequence++;
 446                 /* if there are mutiple output fifos, send a copy of the
 447                  * buffer down all but the first (we have to not ship the
 448                  * original buffer or we'll race with the thread that's
 449                  * consuming the buffer & inject garbage into the data stream). */
 450                 for( n = 1; fifos[n] != NULL; n++)
 451                 {
 452                     hb_buffer_t *buf_copy = hb_buffer_init( buf->size );
 453                     hb_buffer_copy_settings( buf_copy, buf );
 454                     memcpy( buf_copy->data, buf->data, buf->size );
 455                     push_buf( r, fifos[n], buf_copy );
 456                 }
 457                 push_buf( r, fifos[0], buf );
 458             }
 459             else
 460             {
 461                 hb_buffer_close( &buf );
 462             }
 463         }
 464     }
 465
 466   done:
 467     // send empty buffers downstream to video & audio decoders to signal we're done.
 468     if( !*r->die && !r->job->done )
 469     {
 470         push_buf( r, r->job->fifo_mpeg2, hb_buffer_init(0) );
 471
 472         hb_audio_t *audio;
 473         for( n = 0; (audio = hb_list_item( r->job->title->list_audio, n)); ++n )
 474         {
 475             if ( audio->priv.fifo_in )
 476                 push_buf( r, audio->priv.fifo_in, hb_buffer_init(0) );
 477         }
 478
 479         hb_subtitle_t *subtitle;
 480         for( n = 0; (subtitle = hb_list_item( r->job->title->list_subtitle, n)); ++n )
 481         {
 482             if ( subtitle->fifo_in && subtitle->source == VOBSUB)
 483                 push_buf( r, subtitle->fifo_in, hb_buffer_init(0) );
 484         }
 485     }
 486
 487     hb_list_empty( &list );
 488     hb_buffer_close( &ps );
 489     if (r->dvd)
 490     {
 491         hb_dvd_stop( r->dvd );
 492         hb_dvd_close( &r->dvd );
 493     }
 494     else if (r->stream)
 495     {
 496         hb_stream_close(&r->stream);
 497     }
 498
 499     if ( r->stream_timing )
 500     {
 501         free( r->stream_timing );
 502     }
 503
 504     hb_log( "reader: done. %d scr changes", r->demux.scr_changes );
 505     if ( r->demux.dts_drops )
 506     {
 507         hb_log( "reader: %d drops because DTS out of range", r->demux.dts_drops );
 508     }
 509
 510     free( r );
 511     _r = NULL;
 512 }
 513
 514 /***********************************************************************
 515  * GetFifoForId
 516  ***********************************************************************
 517  *
 518  **********************************************************************/
 519 static hb_fifo_t ** GetFifoForId( hb_job_t * job, int id )
 520 {
 521     hb_title_t    * title = job->title;
 522     hb_audio_t    * audio;
 523     hb_subtitle_t * subtitle;
 524     int             i, n, count;
 525     static hb_fifo_t * fifos[100];
 526
 527     memset(fifos, 0, sizeof(fifos));
 528
 529     if( id == title->video_id )
 530     {
 531         if( job->indepth_scan )
 532         {
 533             /*
 534              * Ditch the video here during the indepth scan until
 535              * we can improve the MPEG2 decode performance.
 536              */
 537             return NULL;
 538         }
 539         else
 540         {
 541             fifos[0] = job->fifo_mpeg2;
 542             return fifos;
 543         }
 544     }
 545
 546     n = 0;
 547     count = hb_list_count( title->list_subtitle );
 548     count = count > 99 ? 99 : count;
 549     for( i=0; i < count; i++ ) {
 550         subtitle =  hb_list_item( title->list_subtitle, i );
 551         if (id == subtitle->id) {
 552             subtitle->hits++;
 553             if( !job->indepth_scan || job->select_subtitle_config.force )
 554             {
 555                 /*
 556                  * Pass the subtitles to be processed if we are not scanning, or if
 557                  * we are scanning and looking for forced subs, then pass them up
 558                  * to decode whether the sub is a forced one.
 559                  */
 560                 fifos[n++] = subtitle->fifo_in;
 561             }
 562         }
 563     }
 564     if ( n != 0 )
 565     {
 566         return fifos;
 567     }
 568
 569     if( !job->indepth_scan )
 570     {
 571         n = 0;
 572         for( i = 0; i < hb_list_count( title->list_audio ); i++ )
 573         {
 574             audio = hb_list_item( title->list_audio, i );
 575             if( id == audio->id )
 576             {
 577                 fifos[n++] = audio->priv.fifo_in;
 578             }
 579         }
 580
 581         if( n != 0 )
 582         {
 583             return fifos;
 584         }
 585     }
 586
 587     return NULL;
 588 }
 589