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         st->last = buf->renderOffset - st->average;
 145         if ( ( st->is_audio = is_audio( r, buf->id ) ) != 0 )
 146         {
 147             r->saw_audio = 1;
 148         }
 149         st[1].id = -1;
 150     }
 151     return st;
 152 }
 153
 154 // update the average inter-packet time of the stream associated with 'buf'
 155 // using a recursive low-pass filter with a 16 packet time constant.
 156
 157 static void update_ipt( hb_reader_t *r, const hb_buffer_t *buf )
 158 {
 159     stream_timing_t *st = id_to_st( r, buf );
 160     double dt = buf->renderOffset - st->last;
 161     st->average += ( dt - st->average ) * (1./32.);
 162     st->last = buf->renderOffset;
 163 }
 164
 165 // use the per-stream state associated with 'buf' to compute a new scr_offset
 166 // such that 'buf' will follow the previous packet of this stream separated
 167 // by the average packet time of the stream.
 168
 169 static void new_scr_offset( hb_reader_t *r, hb_buffer_t *buf )
 170 {
 171     stream_timing_t *st = id_to_st( r, buf );
 172     int64_t nxt = st->last + st->average;
 173     r->scr_offset = buf->renderOffset - nxt;
 174     buf->renderOffset = nxt;
 175     r->scr_changes = r->demux.scr_changes;
 176     st->last = buf->renderOffset;
 177 }
 178
 179 /***********************************************************************
 180  * ReaderFunc
 181  ***********************************************************************
 182  *
 183  **********************************************************************/
 184 static void ReaderFunc( void * _r )
 185 {
 186     hb_reader_t  * r = _r;
 187     hb_fifo_t   ** fifos;
 188     hb_buffer_t  * buf;
 189     hb_list_t    * list;
 190     int            n;
 191     int            chapter = -1;
 192     int            chapter_end = r->job->chapter_end;
 193
 194     if( !( r->dvd = hb_dvd_init( r->title->dvd ) ) )
 195     {
 196         if ( !( r->stream = hb_stream_open( r->title->dvd, r->title ) ) )
 197         {
 198           return;
 199         }
 200     }
 201
 202     if (r->dvd)
 203     {
 204         /*
 205          * XXX this code is a temporary hack that should go away if/when
 206          *     chapter merging goes away in libhb/dvd.c
 207          * map the start and end chapter numbers to on-media chapter
 208          * numbers since chapter merging could cause the handbrake numbers
 209          * to diverge from the media numbers and, if our chapter_end is after
 210          * a media chapter that got merged, we'll stop ripping too early.
 211          */
 212         int start = r->job->chapter_start;
 213         hb_chapter_t *chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 214
 215         chapter_end = chap->index;
 216         if (start > 1)
 217         {
 218            chap = hb_list_item( r->title->list_chapter, start - 1 );
 219            start = chap->index;
 220         }
 221         /* end chapter mapping XXX */
 222
 223         if( !hb_dvd_start( r->dvd, r->title, start ) )
 224         {
 225             hb_dvd_close( &r->dvd );
 226             return;
 227         }
 228         if (r->job->angle)
 229         {
 230             hb_dvd_set_angle( r->dvd, r->job->angle );
 231         }
 232
 233         if ( r->job->start_at_preview )
 234         {
 235             // XXX code from DecodePreviews - should go into its own routine
 236             hb_dvd_seek( r->dvd, (float)r->job->start_at_preview /
 237                          ( r->job->seek_points ? ( r->job->seek_points + 1.0 ) : 11.0 ) );
 238         }
 239     }
 240     else if ( r->stream && r->job->start_at_preview )
 241     {
 242
 243         // XXX code from DecodePreviews - should go into its own routine
 244         hb_stream_seek( r->stream, (float)( r->job->start_at_preview - 1 ) /
 245                         ( r->job->seek_points ? ( r->job->seek_points + 1.0 ) : 11.0 ) );
 246
 247     }
 248     else if( r->stream )
 249     {
 250         /*
 251          * Standard stream, seek to the starting chapter, if set, and track the
 252          * end chapter so that we end at the right time.
 253          */
 254         int start = r->job->chapter_start;
 255         hb_chapter_t *chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 256
 257         chapter_end = chap->index;
 258         if (start > 1)
 259         {
 260             chap = hb_list_item( r->title->list_chapter, start - 1 );
 261             start = chap->index;
 262         }
 263
 264         /*
 265          * Seek to the start chapter.
 266          */
 267         hb_stream_seek_chapter( r->stream, start );
 268     }
 269
 270     list  = hb_list_init();
 271     hb_buffer_t *ps = hb_buffer_init( HB_DVD_READ_BUFFER_SIZE );
 272
 273     while( !*r->die && !r->job->done )
 274     {
 275         if (r->dvd)
 276             chapter = hb_dvd_chapter( r->dvd );
 277         else if (r->stream)
 278             chapter = hb_stream_chapter( r->stream );
 279
 280         if( chapter < 0 )
 281         {
 282             hb_log( "reader: end of the title reached" );
 283             break;
 284         }
 285         if( chapter > chapter_end )
 286         {
 287             hb_log( "reader: end of chapter %d (media %d) reached at media chapter %d",
 288                     r->job->chapter_end, chapter_end, chapter );
 289             break;
 290         }
 291
 292         if (r->dvd)
 293         {
 294           if( !hb_dvd_read( r->dvd, ps ) )
 295           {
 296               break;
 297           }
 298         }
 299         else if (r->stream)
 300         {
 301           if ( !hb_stream_read( r->stream, ps ) )
 302           {
 303             break;
 304           }
 305         }
 306
 307         if( r->job->indepth_scan )
 308         {
 309             /*
 310              * Need to update the progress during a subtitle scan
 311              */
 312             hb_state_t state;
 313
 314 #define p state.param.working
 315
 316             state.state = HB_STATE_WORKING;
 317             p.progress = (double)chapter / (double)r->job->chapter_end;
 318             if( p.progress > 1.0 )
 319             {
 320                 p.progress = 1.0;
 321             }
 322             p.rate_avg = 0.0;
 323             p.hours    = -1;
 324             p.minutes  = -1;
 325             p.seconds  = -1;
 326             hb_set_state( r->job->h, &state );
 327         }
 328
 329         (hb_demux[r->title->demuxer])( ps, list, &r->demux );
 330
 331         while( ( buf = hb_list_item( list, 0 ) ) )
 332         {
 333             hb_list_rem( list, buf );
 334             fifos = GetFifoForId( r->job, buf->id );
 335
 336             if ( ! r->saw_video )
 337             {
 338                 /* The first video packet defines 'time zero' so discard
 339                    data until we get a video packet with a PTS & DTS */
 340                 if ( buf->id == r->title->video_id && buf->start != -1 &&
 341                      buf->renderOffset != -1 )
 342                 {
 343                     // force a new scr offset computation
 344                     r->scr_changes = r->demux.scr_changes - 1;
 345                     r->saw_video = 1;
 346                     hb_log( "reader: first SCR %lld", r->demux.last_scr );
 347                 }
 348                 else
 349                 {
 350                     fifos = NULL;
 351                 }
 352             }
 353             if( fifos )
 354             {
 355                 if ( buf->renderOffset != -1 )
 356                 {
 357                     if ( r->scr_changes == r->demux.scr_changes )
 358                     {
 359                         // This packet is referenced to the same SCR as the last.
 360                         // Adjust timestamp to remove the System Clock Reference
 361                         // offset then update the average inter-packet time
 362                         // for this stream.
 363                         buf->renderOffset -= r->scr_offset;
 364                         update_ipt( r, buf );
 365                     }
 366                     else
 367                     {
 368                         // This is the first audio or video packet after an SCR
 369                         // change. Compute a new scr offset that would make this
 370                         // packet follow the last of this stream with the correct
 371                         // average spacing.
 372                         stream_timing_t *st = find_st( r, buf );
 373
 374                         if ( st )
 375                         {
 376                             // if this is the video stream and we don't have
 377                             // audio yet or this is an audio stream
 378                             // generate a new scr
 379                             if ( st->is_audio ||
 380                                  ( st == r->stream_timing && !r->saw_audio ) )
 381                             {
 382                                 new_scr_offset( r, buf );
 383                             }
 384                             else
 385                             {
 386                                 // defer the scr change until we get some
 387                                 // audio since audio has a timestamp per
 388                                 // frame but video & subtitles don't. Clear
 389                                 // the timestamps so the decoder will generate
 390                                 // them from the frame durations.
 391                                 if ( st != r->stream_timing )
 392                                 {
 393                                     // not a video stream so it's probably
 394                                     // subtitles - the best we can do is to
 395                                     // line it up with the last video packet.
 396                                     buf->start = r->stream_timing->last;
 397                                 }
 398                                 else
 399                                 {
 400                                     buf->start = -1;
 401                                     buf->renderOffset = -1;
 402                                 }
 403                             }
 404                         }
 405                         else
 406                         {
 407                             // we got a new scr at the same time as the first
 408                             // packet of a stream we've never seen before. We
 409                             // have no idea what the timing should be so toss
 410                             // this buffer & wait for a stream we've already seen.
 411                             hb_buffer_close( &buf );
 412                             continue;
 413                         }
 414                     }
 415                 }
 416                 if ( buf->start != -1 )
 417                 {
 418                     buf->start -= r->scr_offset;
 419                     if ( r->job->pts_to_stop && buf->start > r->job->pts_to_stop )
 420                     {
 421                         // we're doing a subset of the input and we've hit the
 422                         // stopping point.
 423                         hb_buffer_close( &buf );
 424                         goto done;
 425                     }
 426                 }
 427
 428                 buf->sequence = r->sequence++;
 429                 /* if there are mutiple output fifos, send a copy of the
 430                  * buffer down all but the first (we have to not ship the
 431                  * original buffer or we'll race with the thread that's
 432                  * consuming the buffer & inject garbage into the data stream). */
 433                 for( n = 1; fifos[n] != NULL; n++)
 434                 {
 435                     hb_buffer_t *buf_copy = hb_buffer_init( buf->size );
 436                     hb_buffer_copy_settings( buf_copy, buf );
 437                     memcpy( buf_copy->data, buf->data, buf->size );
 438                     push_buf( r, fifos[n], buf_copy );
 439                 }
 440                 push_buf( r, fifos[0], buf );
 441             }
 442             else
 443             {
 444                 hb_buffer_close( &buf );
 445             }
 446         }
 447     }
 448
 449   done:
 450     // send empty buffers downstream to video & audio decoders to signal we're done.
 451     push_buf( r, r->job->fifo_mpeg2, hb_buffer_init(0) );
 452
 453     hb_audio_t *audio;
 454     for( n = 0; ( audio = hb_list_item( r->job->title->list_audio, n ) ); ++n )
 455     {
 456         if ( audio->priv.fifo_in )
 457             push_buf( r, audio->priv.fifo_in, hb_buffer_init(0) );
 458     }
 459
 460     hb_list_empty( &list );
 461     hb_buffer_close( &ps );
 462     if (r->dvd)
 463     {
 464         hb_dvd_stop( r->dvd );
 465         hb_dvd_close( &r->dvd );
 466     }
 467     else if (r->stream)
 468     {
 469         hb_stream_close(&r->stream);
 470     }
 471
 472     if ( r->stream_timing )
 473     {
 474         free( r->stream_timing );
 475     }
 476
 477     hb_log( "reader: done. %d scr changes", r->demux.scr_changes );
 478     if ( r->demux.dts_drops )
 479     {
 480         hb_log( "reader: %d drops because DTS out of range", r->demux.dts_drops );
 481     }
 482
 483     free( r );
 484     _r = NULL;
 485 }
 486
 487 /***********************************************************************
 488  * GetFifoForId
 489  ***********************************************************************
 490  *
 491  **********************************************************************/
 492 static hb_fifo_t ** GetFifoForId( hb_job_t * job, int id )
 493 {
 494     hb_title_t    * title = job->title;
 495     hb_audio_t    * audio;
 496     hb_subtitle_t * subtitle;
 497     int             i, n;
 498     static hb_fifo_t * fifos[8];
 499
 500     memset(fifos, 0, sizeof(fifos));
 501
 502     if( id == title->video_id )
 503     {
 504         if( job->indepth_scan )
 505         {
 506             /*
 507              * Ditch the video here during the indepth scan until
 508              * we can improve the MPEG2 decode performance.
 509              */
 510             return NULL;
 511         }
 512         else
 513         {
 514             fifos[0] = job->fifo_mpeg2;
 515             return fifos;
 516         }
 517     }
 518
 519     for( i=0; i < hb_list_count( title->list_subtitle ); i++ ) {
 520         subtitle =  hb_list_item( title->list_subtitle, i );
 521         if (id == subtitle->id) {
 522             subtitle->hits++;
 523             if( !job->indepth_scan || job->subtitle_force )
 524             {
 525                 /*
 526                  * Pass the subtitles to be processed if we are not scanning, or if
 527                  * we are scanning and looking for forced subs, then pass them up
 528                  * to decode whether the sub is a forced one.
 529                  */
 530                 fifos[0] = subtitle->fifo_in;
 531                 return fifos;
 532             }
 533             break;
 534         }
 535     }
 536
 537     if( !job->indepth_scan )
 538     {
 539         n = 0;
 540         for( i = 0; i < hb_list_count( title->list_audio ); i++ )
 541         {
 542             audio = hb_list_item( title->list_audio, i );
 543             if( id == audio->id )
 544             {
 545                 fifos[n++] = audio->priv.fifo_in;
 546             }
 547         }
 548
 549         if( n != 0 )
 550         {
 551             return fifos;
 552         }
 553     }
 554
 555     return NULL;
 556 }
 557