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, hb_buffer_t *buf )
 137 {
 138     stream_timing_t *st = id_to_st( r, buf );
 139     int64_t nxt = st->last + st->average;
 140     r->scr_offset = buf->renderOffset - nxt;
 141     buf->renderOffset = nxt;
 142     r->scr_changes = r->demux.scr_changes;
 143     st->last = buf->renderOffset;
 144 }
 145
 146 /***********************************************************************
 147  * ReaderFunc
 148  ***********************************************************************
 149  *
 150  **********************************************************************/
 151 static void ReaderFunc( void * _r )
 152 {
 153     hb_reader_t  * r = _r;
 154     hb_fifo_t   ** fifos;
 155     hb_buffer_t  * buf;
 156     hb_list_t    * list;
 157     int            n;
 158     int            chapter = -1;
 159     int            chapter_end = r->job->chapter_end;
 160
 161     if( !( r->dvd = hb_dvd_init( r->title->dvd ) ) )
 162     {
 163         if ( !( r->stream = hb_stream_open( r->title->dvd, r->title ) ) )
 164         {
 165           return;
 166         }
 167     }
 168
 169     if (r->dvd)
 170     {
 171       /*
 172        * XXX this code is a temporary hack that should go away if/when
 173        *     chapter merging goes away in libhb/dvd.c
 174        * map the start and end chapter numbers to on-media chapter
 175        * numbers since chapter merging could cause the handbrake numbers
 176        * to diverge from the media numbers and, if our chapter_end is after
 177        * a media chapter that got merged, we'll stop ripping too early.
 178        */
 179       int start = r->job->chapter_start;
 180       hb_chapter_t * chap = hb_list_item( r->title->list_chapter, chapter_end - 1 );
 181
 182       chapter_end = chap->index;
 183       if (start > 1)
 184       {
 185          chap = hb_list_item( r->title->list_chapter, start - 1 );
 186          start = chap->index;
 187       }
 188       /* end chapter mapping XXX */
 189
 190       if( !hb_dvd_start( r->dvd, r->title->index, start ) )
 191       {
 192           hb_dvd_close( &r->dvd );
 193           return;
 194       }
 195     }
 196
 197     list  = hb_list_init();
 198     hb_buffer_t *ps = hb_buffer_init( HB_DVD_READ_BUFFER_SIZE );
 199
 200     while( !*r->die && !r->job->done )
 201     {
 202         if (r->dvd)
 203           chapter = hb_dvd_chapter( r->dvd );
 204         else if (r->stream)
 205           chapter = 1;
 206
 207         if( chapter < 0 )
 208         {
 209             hb_log( "reader: end of the title reached" );
 210             break;
 211         }
 212         if( chapter > chapter_end )
 213         {
 214             hb_log( "reader: end of chapter %d (media %d) reached at media chapter %d",
 215                     r->job->chapter_end, chapter_end, chapter );
 216             break;
 217         }
 218
 219         if (r->dvd)
 220         {
 221           if( !hb_dvd_read( r->dvd, ps ) )
 222           {
 223               break;
 224           }
 225         }
 226         else if (r->stream)
 227         {
 228           if ( !hb_stream_read( r->stream, ps ) )
 229           {
 230             break;
 231           }
 232         }
 233
 234         if( r->job->indepth_scan )
 235         {
 236             /*
 237              * Need to update the progress during a subtitle scan
 238              */
 239             hb_state_t state;
 240
 241 #define p state.param.working
 242
 243             state.state = HB_STATE_WORKING;
 244             p.progress = (double)chapter / (double)r->job->chapter_end;
 245             if( p.progress > 1.0 )
 246             {
 247                 p.progress = 1.0;
 248             }
 249             p.rate_avg = 0.0;
 250             p.hours    = -1;
 251             p.minutes  = -1;
 252             p.seconds  = -1;
 253             hb_set_state( r->job->h, &state );
 254         }
 255
 256         if ( r->title->demuxer == HB_NULL_DEMUXER )
 257         {
 258             hb_demux_null( ps, list, &r->demux );
 259         }
 260         else
 261         {
 262             hb_demux_ps( ps, list, &r->demux );
 263         }
 264
 265         while( ( buf = hb_list_item( list, 0 ) ) )
 266         {
 267             hb_list_rem( list, buf );
 268             fifos = GetFifoForId( r->job, buf->id );
 269
 270             if ( ! r->saw_video )
 271             {
 272                 /* The first video packet defines 'time zero' so discard
 273                    data until we get a video packet with a PTS & DTS */
 274                 if ( buf->id == r->title->video_id && buf->start != -1 &&
 275                      buf->renderOffset != -1 )
 276                 {
 277                     r->saw_video = 1;
 278                     r->scr_changes = r->demux.scr_changes;
 279                     new_scr_offset( r, buf );
 280                     hb_log( "reader: first SCR %lld scr_offset %lld",
 281                             r->demux.last_scr, r->scr_offset );
 282                 }
 283                 else
 284                 {
 285                     fifos = NULL;
 286                 }
 287             }
 288             if( fifos )
 289             {
 290                 if ( buf->renderOffset != -1 )
 291                 {
 292                     if ( r->scr_changes == r->demux.scr_changes )
 293                     {
 294                         // This packet is referenced to the same SCR as the last.
 295                         // Adjust timestamp to remove the System Clock Reference
 296                         // offset then update the average inter-packet time
 297                         // for this stream.
 298                         buf->renderOffset -= r->scr_offset;
 299                         update_ipt( r, buf );
 300                     }
 301                     else
 302                     {
 303                         // This is the first audio or video packet after an SCR
 304                         // change. Compute a new scr offset that would make this
 305                         // packet follow the last of this stream with the correct
 306                         // average spacing.
 307                         new_scr_offset( r, buf );
 308                     }
 309                 }
 310                 if ( buf->start != -1 )
 311                     buf->start -= r->scr_offset;
 312
 313                 buf->sequence = r->sequence++;
 314                 /* if there are mutiple output fifos, send a copy of the
 315                  * buffer down all but the first (we have to not ship the
 316                  * original buffer or we'll race with the thread that's
 317                  * consuming the buffer & inject garbage into the data stream). */
 318                 for( n = 1; fifos[n] != NULL; n++)
 319                 {
 320                     hb_buffer_t *buf_copy = hb_buffer_init( buf->size );
 321                     hb_buffer_copy_settings( buf_copy, buf );
 322                     memcpy( buf_copy->data, buf->data, buf->size );
 323                     push_buf( r, fifos[n], buf_copy );
 324                 }
 325                 push_buf( r, fifos[0], buf );
 326             }
 327             else
 328             {
 329                 hb_buffer_close( &buf );
 330             }
 331         }
 332     }
 333
 334     // send empty buffers downstream to video & audio decoders to signal we're done.
 335     push_buf( r, r->job->fifo_mpeg2, hb_buffer_init(0) );
 336
 337     hb_audio_t *audio;
 338     for( n = 0; ( audio = hb_list_item( r->job->title->list_audio, n ) ); ++n )
 339     {
 340         if ( audio->priv.fifo_in )
 341             push_buf( r, audio->priv.fifo_in, hb_buffer_init(0) );
 342     }
 343
 344     hb_list_empty( &list );
 345     hb_buffer_close( &ps );
 346     if (r->dvd)
 347     {
 348         hb_dvd_stop( r->dvd );
 349         hb_dvd_close( &r->dvd );
 350     }
 351     else if (r->stream)
 352     {
 353         hb_stream_close(&r->stream);
 354     }
 355
 356     if ( r->stream_timing )
 357     {
 358         free( r->stream_timing );
 359     }
 360
 361     hb_log( "reader: done. %d scr changes", r->demux.scr_changes );
 362
 363     free( r );
 364     _r = NULL;
 365 }
 366
 367 /***********************************************************************
 368  * GetFifoForId
 369  ***********************************************************************
 370  *
 371  **********************************************************************/
 372 static hb_fifo_t ** GetFifoForId( hb_job_t * job, int id )
 373 {
 374     hb_title_t    * title = job->title;
 375     hb_audio_t    * audio;
 376     hb_subtitle_t * subtitle;
 377     int             i, n;
 378     static hb_fifo_t * fifos[8];
 379
 380     memset(fifos, 0, sizeof(fifos));
 381
 382     if( id == title->video_id )
 383     {
 384         if( job->indepth_scan )
 385         {
 386             /*
 387              * Ditch the video here during the indepth scan until
 388              * we can improve the MPEG2 decode performance.
 389              */
 390             return NULL;
 391         }
 392         else
 393         {
 394             fifos[0] = job->fifo_mpeg2;
 395             return fifos;
 396         }
 397     }
 398
 399     if( job->indepth_scan ) {
 400         /*
 401          * Count the occurances of the subtitles, don't actually
 402          * return any to encode unless we are looking fro forced
 403          * subtitles in which case we need to look in the sub picture
 404          * to see if it has the forced flag enabled.
 405          */
 406         for (i=0; i < hb_list_count(title->list_subtitle); i++) {
 407             subtitle =  hb_list_item( title->list_subtitle, i);
 408             if (id == subtitle->id) {
 409                 /*
 410                  * A hit, count it.
 411                  */
 412                 subtitle->hits++;
 413                 if( job->subtitle_force )
 414                 {
 415
 416                     fifos[0] = subtitle->fifo_in;
 417                     return fifos;
 418                 }
 419                 break;
 420             }
 421         }
 422     } else {
 423         if( ( subtitle = hb_list_item( title->list_subtitle, 0 ) ) &&
 424             id == subtitle->id )
 425         {
 426             fifos[0] = subtitle->fifo_in;
 427             return fifos;
 428         }
 429     }
 430     if( !job->indepth_scan )
 431     {
 432         n = 0;
 433         for( i = 0; i < hb_list_count( title->list_audio ); i++ )
 434         {
 435             audio = hb_list_item( title->list_audio, i );
 436             if( id == audio->id )
 437             {
 438                 fifos[n++] = audio->priv.fifo_in;
 439             }
 440         }
 441
 442         if( n != 0 )
 443         {
 444             return fifos;
 445         }
 446     }
 447
 448     return NULL;
 449 }
 450