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     int64_t last;   // last timestamp seen on this stream
  12     double average; // average time between packets
  13     int id;         // stream id
  14 } stream_timing_t;
  15
  16 typedef struct
  17 {
  18     hb_job_t     * job;
  19     hb_title_t   * title;
  20     volatile int * die;
  21
  22     hb_dvd_t     * dvd;
  23     hb_stream_t  * stream;
  24
  25     stream_timing_t *stream_timing;
  26     int64_t        scr_offset;
  27     hb_psdemux_t   demux;
  28     int            scr_changes;
  29     uint           sequence;
  30     int            saw_video;
  31     int            st_slots;            // size (in slots) of stream_timing array
  32 } hb_reader_t;
  33
  34 /***********************************************************************
  35  * Local prototypes
  36  **********************************************************************/
  37 static void        ReaderFunc( void * );
  38 static hb_fifo_t ** GetFifoForId( hb_job_t * job, int id );
  39
  40 /***********************************************************************
  41  * hb_reader_init
  42  ***********************************************************************
  43  *
  44  **********************************************************************/
  45 hb_thread_t * hb_reader_init( hb_job_t * job )
  46 {
  47     hb_reader_t * r;
  48
  49     r = calloc( sizeof( hb_reader_t ), 1 );
  50
  51     r->job   = job;
  52     r->title = job->title;
  53     r->die   = job->die;
  54     r->sequence = 0;
  55
  56     r->st_slots = 4;
  57     r->stream_timing = calloc( sizeof(stream_timing_t), r->st_slots );
  58     r->stream_timing[0].id = r->title->video_id;
  59     r->stream_timing[0].average = 90000. * (double)job->vrate_base /
  60                                            (double)job->vrate;
  61     r->stream_timing[0].last = -r->stream_timing[0].average;
  62     r->stream_timing[1].id = -1;
  63
  64     return hb_thread_init( "reader", ReaderFunc, r,
  65                            HB_NORMAL_PRIORITY );
  66 }
  67
  68 static void push_buf( const hb_reader_t *r, hb_fifo_t *fifo, hb_buffer_t *buf )
  69 {
  70     while( !*r->die && !r->job->done && hb_fifo_is_full( fifo ) )
  71     {
  72         /*
  73          * Loop until the incoming fifo is ready to receive
  74          * this buffer.
  75          */
  76         hb_snooze( 50 );
  77     }
  78     hb_fifo_push( fifo, buf );
  79 }
  80
  81 // The MPEG STD (Standard Target Decoder) essentially requires that we keep
  82 // per-stream timing so that when there's a timing discontinuity we can
  83 // seemlessly join packets on either side of the discontinuity. This join
  84 // requires that we know the timestamp of the previous packet and the
  85 // average inter-packet time (since we position the new packet at the end
  86 // of the previous packet). The next three routines keep track of this
  87 // per-stream timing.
  88
  89 // find the per-stream timing state associated with 'buf'
  90
  91 static stream_timing_t *id_to_st( hb_reader_t *r, const hb_buffer_t *buf )
  92 {
  93     stream_timing_t *st = r->stream_timing;
  94     while ( st->id != buf->id && st->id != -1)
  95     {
  96         ++st;
  97     }
  98     // if we haven't seen this stream add it.
  99     if ( st->id == -1 )
 100     {
 101         // we keep the steam timing info in an array with some power-of-two
 102         // number of slots. If we don't have two slots left (one for our new
 103         // entry plus one for the "-1" eol) we need to expand the array.
 104         int slot = st - r->stream_timing;
 105         if ( slot + 1 >= r->st_slots )
 106         {
 107             r->st_slots *= 2;
 108             r->stream_timing = realloc( r->stream_timing, r->st_slots *
 109                                         sizeof(*r->stream_timing) );
 110             st = r->stream_timing + slot;
 111         }
 112         st->id = buf->id;
 113         st->average = 30.*90.;
 114         st->last = buf->renderOffset - st->average;
 115
 116         st[1].id = -1;
 117     }
 118     return st;
 119 }
 120
 121 // update the average inter-packet time of the stream associated with 'buf'
 122 // using a recursive low-pass filter with a 16 packet time constant.
 123
 124 static void update_ipt( hb_reader_t *r, const hb_buffer_t *buf )
 125 {
 126     stream_timing_t *st = id_to_st( r, buf );
 127     double dt = buf->renderOffset - st->last;
 128     st->average += ( dt - st->average ) * (1./16.);
 129     st->last = buf->renderOffset;
 130 }
 131
 132 // use the per-stream state associated with 'buf' to compute a new scr_offset
 133 // such that 'buf' will follow the previous packet of this stream separated
 134 // by the average packet time of the stream.
 135
 136 static void new_scr_offset( hb_reader_t *r, const hb_buffer_t *buf )
 137 {
 138     stream_timing_t *st = id_to_st( r, buf );
 139     int64_t nxt = st->last + st->average - r->scr_offset;
 140     r->scr_offset = buf->renderOffset - nxt;
 141     r->scr_changes = r->demux.scr_changes;
 142     st->last = buf->renderOffset;
 143 }
 144
 145 /***********************************************************************
 146  * ReaderFunc
 147  ***********************************************************************
 148  *
 149  **********************************************************************/
 150 static void ReaderFunc( void * _r )
 151 {
 152     hb_reader_t  * r = _r;
 153     hb_fifo_t   ** fifos;
 154     hb_buffer_t  * buf;
 155     hb_list_t    * list;
 156     int            n;
 157     int            chapter = -1;
 158     int            chapter_end = r->job->chapter_end;
 159
 160     if( !( r->dvd = hb_dvd_init( r->title->dvd ) ) )
 161     {
 162         if ( !( r->stream = hb_stream_open( r->title->dvd, r->title ) ) )
 163         {
 164           return;
 165         }
 166     }
 167
 168     if (r->dvd)
 169     {
 170       /*
 171        * XXX this code is a temporary hack that should go away if/when
 172        *     chapter merging goes away in libhb/dvd.c
 173        * map the start and end chapter numbers to on-media chapter
 174        * numbers since chapter merging could cause the handbrake numbers
 175        * to diverge from the media numbers and, if our chapter_end is after
 176        * a media chapter that got merged, we'll stop ripping too early.
 177        */
 178       int start = r->job->chapter_start;
 179       hb_chapter_t * chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 180
 181       chapter_end = chap->index;
 182       if (start > 1)
 183       {
 184          chap = hb_list_item( r->title->list_chapter, start - 1 );
 185          start = chap->index;
 186       }
 187       /* end chapter mapping XXX */
 188
 189       if( !hb_dvd_start( r->dvd, r->title->index, start ) )
 190       {
 191           hb_dvd_close( &r->dvd );
 192           return;
 193       }
 194     }
 195
 196     list  = hb_list_init();
 197     hb_buffer_t *ps = hb_buffer_init( HB_DVD_READ_BUFFER_SIZE );
 198
 199     while( !*r->die && !r->job->done )
 200     {
 201         if (r->dvd)
 202           chapter = hb_dvd_chapter( r->dvd );
 203         else if (r->stream)
 204           chapter = 1;
 205
 206         if( chapter < 0 )
 207         {
 208             hb_log( "reader: end of the title reached" );
 209             break;
 210         }
 211         if( chapter > chapter_end )
 212         {
 213             hb_log( "reader: end of chapter %d (media %d) reached at media chapter %d",
 214                     r->job->chapter_end, chapter_end, chapter );
 215             break;
 216         }
 217
 218         if (r->dvd)
 219         {
 220           if( !hb_dvd_read( r->dvd, ps ) )
 221           {
 222               break;
 223           }
 224         }
 225         else if (r->stream)
 226         {
 227           if ( !hb_stream_read( r->stream, ps ) )
 228           {
 229             break;
 230           }
 231         }
 232
 233         if( r->job->indepth_scan )
 234         {
 235             /*
 236              * Need to update the progress during a subtitle scan
 237              */
 238             hb_state_t state;
 239
 240 #define p state.param.working
 241
 242             state.state = HB_STATE_WORKING;
 243             p.progress = (double)chapter / (double)r->job->chapter_end;
 244             if( p.progress > 1.0 )
 245             {
 246                 p.progress = 1.0;
 247             }
 248             p.rate_avg = 0.0;
 249             p.hours    = -1;
 250             p.minutes  = -1;
 251             p.seconds  = -1;
 252             hb_set_state( r->job->h, &state );
 253         }
 254
 255         if ( r->title->demuxer == HB_NULL_DEMUXER )
 256         {
 257             hb_demux_null( ps, list, &r->demux );
 258         }
 259         else
 260         {
 261             hb_demux_ps( ps, list, &r->demux );
 262         }
 263
 264         while( ( buf = hb_list_item( list, 0 ) ) )
 265         {
 266             hb_list_rem( list, buf );
 267             fifos = GetFifoForId( r->job, buf->id );
 268
 269             if ( ! r->saw_video )
 270             {
 271                 /* The first video packet defines 'time zero' so discard
 272                    data until we get a video packet with a PTS & DTS */
 273                 if ( buf->id == r->title->video_id && buf->start != -1 &&
 274                      buf->renderOffset != -1 )
 275                 {
 276                     r->saw_video = 1;
 277                     r->scr_changes = r->demux.scr_changes;
 278                     new_scr_offset( r, buf );
 279                     hb_log( "reader: first SCR %lld scr_offset %lld",
 280                             r->demux.last_scr, r->scr_offset );
 281                 }
 282                 else
 283                 {
 284                     fifos = NULL;
 285                 }
 286             }
 287             if( fifos )
 288             {
 289                 if ( buf->renderOffset != -1 )
 290                 {
 291                     if ( r->scr_changes == r->demux.scr_changes )
 292                     {
 293                         // This packet is referenced to the same SCR as the last.
 294                         // Update the average inter-packet time for this stream.
 295                         update_ipt( r, buf );
 296                     }
 297                     else
 298                     {
 299                         // This is the first audio or video packet after an SCR
 300                         // change. Compute a new scr offset that would make this
 301                         // packet follow the last of this stream with the correct
 302                         // average spacing.
 303                         new_scr_offset( r, buf );
 304                     }
 305                     // adjust timestamps to remove System Clock Reference offsets.
 306                     buf->renderOffset -= r->scr_offset;
 307                 }
 308                 if ( buf->start != -1 )
 309                     buf->start -= r->scr_offset;
 310
 311                 buf->sequence = r->sequence++;
 312                 /* if there are mutiple output fifos, send a copy of the
 313                  * buffer down all but the first (we have to not ship the
 314                  * original buffer or we'll race with the thread that's
 315                  * consuming the buffer & inject garbage into the data stream). */
 316                 for( n = 1; fifos[n] != NULL; n++)
 317                 {
 318                     hb_buffer_t *buf_copy = hb_buffer_init( buf->size );
 319                     hb_buffer_copy_settings( buf_copy, buf );
 320                     memcpy( buf_copy->data, buf->data, buf->size );
 321                     push_buf( r, fifos[n], buf_copy );
 322                 }
 323                 push_buf( r, fifos[0], buf );
 324             }
 325             else
 326             {
 327                 hb_buffer_close( &buf );
 328             }
 329         }
 330     }
 331
 332     // send empty buffers downstream to video & audio decoders to signal we're done.
 333     push_buf( r, r->job->fifo_mpeg2, hb_buffer_init(0) );
 334
 335     hb_audio_t *audio;
 336     for( n = 0; ( audio = hb_list_item( r->job->title->list_audio, n ) ); ++n )
 337     {
 338         if ( audio->priv.fifo_in )
 339             push_buf( r, audio->priv.fifo_in, hb_buffer_init(0) );
 340     }
 341
 342     hb_list_empty( &list );
 343     hb_buffer_close( &ps );
 344     if (r->dvd)
 345     {
 346         hb_dvd_stop( r->dvd );
 347         hb_dvd_close( &r->dvd );
 348     }
 349     else if (r->stream)
 350     {
 351         hb_stream_close(&r->stream);
 352     }
 353
 354     if ( r->stream_timing )
 355     {
 356         free( r->stream_timing );
 357     }
 358
 359     hb_log( "reader: done. %d scr changes", r->demux.scr_changes );
 360
 361     free( r );
 362     _r = NULL;
 363 }
 364
 365 /***********************************************************************
 366  * GetFifoForId
 367  ***********************************************************************
 368  *
 369  **********************************************************************/
 370 static hb_fifo_t ** GetFifoForId( hb_job_t * job, int id )
 371 {
 372     hb_title_t    * title = job->title;
 373     hb_audio_t    * audio;
 374     hb_subtitle_t * subtitle;
 375     int             i, n;
 376     static hb_fifo_t * fifos[8];
 377
 378     memset(fifos, 0, sizeof(fifos));
 379
 380     if( id == title->video_id )
 381     {
 382         if( job->indepth_scan )
 383         {
 384             /*
 385              * Ditch the video here during the indepth scan until
 386              * we can improve the MPEG2 decode performance.
 387              */
 388             return NULL;
 389         }
 390         else
 391         {
 392             fifos[0] = job->fifo_mpeg2;
 393             return fifos;
 394         }
 395     }
 396
 397     if( job->indepth_scan ) {
 398         /*
 399          * Count the occurances of the subtitles, don't actually
 400          * return any to encode unless we are looking fro forced
 401          * subtitles in which case we need to look in the sub picture
 402          * to see if it has the forced flag enabled.
 403          */
 404         for (i=0; i < hb_list_count(title->list_subtitle); i++) {
 405             subtitle =  hb_list_item( title->list_subtitle, i);
 406             if (id == subtitle->id) {
 407                 /*
 408                  * A hit, count it.
 409                  */
 410                 subtitle->hits++;
 411                 if( job->subtitle_force )
 412                 {
 413
 414                     fifos[0] = subtitle->fifo_in;
 415                     return fifos;
 416                 }
 417                 break;
 418             }
 419         }
 420     } else {
 421         if( ( subtitle = hb_list_item( title->list_subtitle, 0 ) ) &&
 422             id == subtitle->id )
 423         {
 424             fifos[0] = subtitle->fifo_in;
 425             return fifos;
 426         }
 427     }
 428     if( !job->indepth_scan )
 429     {
 430         n = 0;
 431         for( i = 0; i < hb_list_count( title->list_audio ); i++ )
 432         {
 433             audio = hb_list_item( title->list_audio, i );
 434             if( id == audio->id )
 435             {
 436                 fifos[n++] = audio->priv.fifo_in;
 437             }
 438         }
 439
 440         if( n != 0 )
 441         {
 442             return fifos;
 443         }
 444     }
 445
 446     return NULL;
 447 }
 448