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