git.sesse.net Git - vlc/blob - src/input/mpeg_system.c

   1 /*****************************************************************************
   2  * mpeg_system.c: TS, PS and PES management
   3  *****************************************************************************
   4  * Copyright (C) 1998, 1999, 2000 VideoLAN
   5  * $Id: mpeg_system.c,v 1.29 2001/02/07 15:32:26 massiot Exp $
   6  *
   7  * Authors:
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include "defs.h"
  28
  29 #include <stdlib.h>
  30
  31 #include "config.h"
  32 #include "common.h"
  33 #include "threads.h"
  34 #include "mtime.h"
  35
  36 #include "intf_msg.h"
  37
  38 #include "stream_control.h"
  39 #include "input_ext-intf.h"
  40 #include "input_ext-dec.h"
  41
  42 #include "input.h"
  43 #include "mpeg_system.h"
  44
  45 #include "main.h"                           /* AC3/MPEG channel, SPU channel */
  46
  47 /*****************************************************************************
  48  * Local prototypes
  49  *****************************************************************************/
  50
  51
  52 /*
  53  * PES Packet management
  54  */
  55
  56 /*****************************************************************************
  57  * MoveChunk
  58  *****************************************************************************
  59  * Small utility function used to parse discontinuous headers safely. Copies
  60  * i_buf_len bytes of data to a buffer and returns the size copied.
  61  * This is a variation on the theme of input_ext-dec.h:GetChunk().
  62  *****************************************************************************/
  63 static __inline__ size_t MoveChunk( byte_t * p_dest,
  64                                     data_packet_t ** pp_data_src,
  65                                     byte_t ** pp_src,
  66                                     size_t i_buf_len )
  67 {
  68     ptrdiff_t           i_available;
  69
  70     if( (i_available = (*pp_data_src)->p_payload_end - *pp_src)
  71             >= i_buf_len )
  72     {
  73         if( p_dest != NULL )
  74             memcpy( p_dest, *pp_src, i_buf_len );
  75         *pp_src += i_buf_len;
  76         return( i_buf_len );
  77     }
  78     else
  79     {
  80         size_t          i_init_len = i_buf_len;
  81
  82         do
  83         {
  84             if( p_dest != NULL )
  85                 memcpy( p_dest, *pp_src, i_available );
  86             *pp_data_src = (*pp_data_src)->p_next;
  87             i_buf_len -= i_available;
  88             p_dest += i_available;
  89             if( *pp_data_src == NULL )
  90             {
  91                 *pp_src = NULL;
  92                 return( i_init_len - i_buf_len );
  93             }
  94             *pp_src = (*pp_data_src)->p_payload_start;
  95         }
  96         while( (i_available = (*pp_data_src)->p_payload_end - *pp_src)
  97                 <= i_buf_len );
  98
  99         if( i_buf_len )
 100         {
 101             if( p_dest != NULL )
 102                 memcpy( p_dest, *pp_src, i_buf_len );
 103             *pp_src += i_buf_len;
 104         }
 105         return( i_init_len );
 106     }
 107 }
 108
 109 /*****************************************************************************
 110  * input_ParsePES
 111  *****************************************************************************
 112  * Parse a finished PES packet and analyze its header.
 113  *****************************************************************************/
 114 #define PES_HEADER_SIZE     7
 115 void input_ParsePES( input_thread_t * p_input, es_descriptor_t * p_es )
 116 {
 117     data_packet_t * p_data;
 118     byte_t *        p_byte;
 119     byte_t          p_header[PES_HEADER_SIZE];
 120     int             i_done;
 121
 122 #define p_pes (p_es->p_pes)
 123
 124     //intf_DbgMsg("End of PES packet %p", p_pes);
 125
 126     /* Parse the header. The header has a variable length, but in order
 127      * to improve the algorithm, we will read the 14 bytes we may be
 128      * interested in */
 129     p_data = p_pes->p_first;
 130     p_byte = p_data->p_payload_start;
 131     i_done = 0;
 132
 133     if( MoveChunk( p_header, &p_data, &p_byte, PES_HEADER_SIZE )
 134             != PES_HEADER_SIZE )
 135     {
 136         intf_WarnMsg( 3, "PES packet too short to have a header" );
 137         p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 138         p_pes = NULL;
 139         return;
 140     }
 141
 142     /* Get the PES size if defined */
 143     p_es->i_pes_real_size = U16_AT(p_header + 4) + 6;
 144
 145     /* First read the 6 header bytes common to all PES packets:
 146      * use them to test the PES validity */
 147     if( (p_header[0] || p_header[1] || (p_header[2] != 1)) )
 148     {
 149         /* packet_start_code_prefix != 0x000001 */
 150         intf_ErrMsg( "PES packet doesn't start with 0x000001 : data loss" );
 151         p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 152         p_pes = NULL;
 153     }
 154     else
 155     {
 156         int i_pes_header_size, i_payload_size;
 157
 158         if ( p_es->i_pes_real_size &&
 159              (p_es->i_pes_real_size != p_pes->i_pes_size) )
 160         {
 161             /* PES_packet_length is set and != total received payload */
 162             /* Warn the decoder that the data may be corrupt. */
 163             intf_WarnMsg( 3, "PES sizes do not match : packet corrupted" );
 164             p_pes->b_messed_up = 1;
 165         }
 166
 167         switch( p_es->i_stream_id )
 168         {
 169         case 0xBC:  /* Program stream map */
 170         case 0xBE:  /* Padding */
 171         case 0xBF:  /* Private stream 2 */
 172         case 0xB0:  /* ECM */
 173         case 0xB1:  /* EMM */
 174         case 0xFF:  /* Program stream directory */
 175         case 0xF2:  /* DSMCC stream */
 176         case 0xF8:  /* ITU-T H.222.1 type E stream */
 177             /* The payload begins immediately after the 6 bytes header, so
 178              * we have finished with the parsing */
 179             i_pes_header_size = 6;
 180             break;
 181
 182         default:
 183             if( (p_header[6] & 0xC0) == 0x80 )
 184             {
 185                 /* MPEG-2 : the PES header contains at least 3 more bytes. */
 186                 size_t      i_max_len;
 187                 boolean_t   b_has_pts, b_has_dts;
 188                 byte_t      p_full_header[12];
 189
 190                 p_pes->b_data_alignment = p_header[6] & 0x04;
 191
 192                 i_max_len = MoveChunk( p_full_header, &p_data, &p_byte, 12 );
 193                 if( i_max_len < 2 )
 194                 {
 195                     intf_WarnMsg( 3,
 196                             "PES packet too short to have a MPEG-2 header" );
 197                     p_input->p_plugin->pf_delete_pes( p_input->p_method_data,
 198                                                       p_pes );
 199                     p_pes = NULL;
 200                     return;
 201                 }
 202
 203                 b_has_pts = p_full_header[0] & 0x80;
 204                 b_has_dts = p_full_header[0] & 0x40;
 205                 i_pes_header_size = p_full_header[1] + 9;
 206
 207                 /* Now parse the optional header extensions */
 208                 if( b_has_pts )
 209                 {
 210                     if( i_max_len < 7 )
 211                     {
 212                         intf_WarnMsg( 3,
 213                             "PES packet too short to have a MPEG-2 header" );
 214                         p_input->p_plugin->pf_delete_pes(
 215                                                       p_input->p_method_data,
 216                                                       p_pes );
 217                         p_pes = NULL;
 218                         return;
 219                     }
 220                     p_pes->i_pts = input_ClockGetTS( p_input, p_es->p_pgrm,
 221                     ( ((mtime_t)(p_full_header[2] & 0x0E) << 29) |
 222                       (((mtime_t)U16_AT(p_full_header + 3) << 14) - (1 << 14)) |
 223                       ((mtime_t)U16_AT(p_full_header + 5) >> 1) ) );
 224
 225                     if( b_has_dts )
 226                     {
 227                         if( i_max_len < 12 )
 228                         {
 229                             intf_WarnMsg( 3,
 230                               "PES packet too short to have a MPEG-2 header" );
 231                             p_input->p_plugin->pf_delete_pes(
 232                                     p_input->p_method_data,
 233                                     p_pes );
 234                             p_pes = NULL;
 235                             return;
 236                         }
 237                         p_pes->i_dts = input_ClockGetTS( p_input, p_es->p_pgrm,
 238                         ( ((mtime_t)(p_full_header[7] & 0x0E) << 29) |
 239                           (((mtime_t)U16_AT(p_full_header + 8) << 14)
 240                                 - (1 << 14)) |
 241                           ((mtime_t)U16_AT(p_full_header + 10) >> 1) ) );
 242                     }
 243                 }
 244             }
 245             else
 246             {
 247                 /* Probably MPEG-1 */
 248                 boolean_t       b_has_pts, b_has_dts;
 249
 250                 i_pes_header_size = 6;
 251                 p_data = p_pes->p_first;
 252                 p_byte = p_data->p_payload_start;
 253                 /* Cannot fail because the previous one succeeded. */
 254                 MoveChunk( NULL, &p_data, &p_byte, 6 );
 255
 256                 while( *p_byte == 0xFF && i_pes_header_size < 22 )
 257                 {
 258                     i_pes_header_size++;
 259                     if( MoveChunk( NULL, &p_data, &p_byte, 1 ) != 1 )
 260                     {
 261                         intf_WarnMsg( 3,
 262                             "PES packet too short to have a MPEG-1 header" );
 263                         p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 264                         p_pes = NULL;
 265                         return;
 266                     }
 267                 }
 268                 if( i_pes_header_size == 22 )
 269                 {
 270                     intf_ErrMsg( "Too much MPEG-1 stuffing" );
 271                     p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 272                     p_pes = NULL;
 273                     return;
 274                 }
 275
 276                 if( (*p_byte & 0xC0) == 0x40 )
 277                 {
 278                     /* Don't ask why... --Meuuh */
 279                     /* Erm... why ? --Sam */
 280                     /* Well... According to the recommendation, it is for
 281                      * STD_buffer_scale and STD_buffer_size. --Meuuh */
 282                     i_pes_header_size += 2;
 283                     if( MoveChunk( NULL, &p_data, &p_byte, 2 ) != 2 )
 284                     {
 285                         intf_WarnMsg( 3,
 286                             "PES packet too short to have a MPEG-1 header" );
 287                         p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 288                         p_pes = NULL;
 289                         return;
 290                     }
 291                 }
 292
 293                 i_pes_header_size++;
 294
 295                 b_has_pts = *p_byte & 0x20;
 296                 b_has_dts = *p_byte & 0x10;
 297
 298                 if( b_has_pts )
 299                 {
 300                     byte_t      p_ts[5];
 301
 302                     i_pes_header_size += 4;
 303                     if( MoveChunk( p_ts, &p_data, &p_byte, 5 ) != 5 )
 304                     {
 305                         intf_WarnMsg( 3,
 306                             "PES packet too short to have a MPEG-1 header" );
 307                         p_input->p_plugin->pf_delete_pes(
 308                                             p_input->p_method_data, p_pes );
 309                         p_pes = NULL;
 310                         return;
 311                     }
 312
 313                     p_pes->i_pts = input_ClockGetTS( p_input, p_es->p_pgrm,
 314                       ( ((mtime_t)(p_ts[0] & 0x0E) << 29) |
 315                         (((mtime_t)U16_AT(p_ts + 1) << 14) - (1 << 14)) |
 316                         ((mtime_t)U16_AT(p_ts + 3) >> 1) ) );
 317
 318                     if( b_has_dts )
 319                     {
 320                         i_pes_header_size += 5;
 321                         if( MoveChunk( p_ts, &p_data, &p_byte, 5 ) != 5 )
 322                         {
 323                             intf_WarnMsg( 3,
 324                               "PES packet too short to have a MPEG-1 header" );
 325                             p_input->p_plugin->pf_delete_pes(
 326                                     p_input->p_method_data, p_pes );
 327                             p_pes = NULL;
 328                             return;
 329                         }
 330
 331                         p_pes->i_dts = input_ClockGetTS( p_input,
 332                                                          p_es->p_pgrm,
 333                             ( ((mtime_t)(p_ts[0] & 0x0E) << 29) |
 334                               (((mtime_t)U16_AT(p_ts + 1) << 14) - (1 << 14)) |
 335                               ((mtime_t)U16_AT(p_ts + 3) >> 1) ) );
 336                     }
 337                 }
 338             }
 339
 340             break;
 341         }
 342
 343         if( p_es->i_stream_id == 0xbd )
 344         {
 345             /* With private stream 1, the first byte of the payload
 346              * is a stream_private_id, so skip it. */
 347             i_pes_header_size++;
 348         }
 349
 350         /* Now we've parsed the header, we just have to indicate in some
 351          * specific data packets where the PES payload begins (renumber
 352          * p_payload_start), so that the decoders can find the beginning
 353          * of their data right out of the box. */
 354         p_data = p_pes->p_first;
 355         i_payload_size = p_data->p_payload_end
 356                                  - p_data->p_payload_start;
 357         while( i_pes_header_size > i_payload_size )
 358         {
 359             /* These packets are entirely filled by the PES header. */
 360             i_pes_header_size -= i_payload_size;
 361             p_data->p_payload_start = p_data->p_payload_end;
 362             /* Go to the next data packet. */
 363             if( (p_data = p_data->p_next) == NULL )
 364             {
 365                 intf_ErrMsg( "PES header bigger than payload" );
 366                 p_input->p_plugin->pf_delete_pes( p_input->p_method_data,
 367                                                   p_pes );
 368                 p_pes = NULL;
 369                 return;
 370             }
 371             i_payload_size = p_data->p_payload_end
 372                                  - p_data->p_payload_start;
 373         }
 374         /* This last packet is partly header, partly payload. */
 375         if( i_payload_size < i_pes_header_size )
 376         {
 377             intf_ErrMsg( "PES header bigger than payload" );
 378             p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 379             p_pes = NULL;
 380             return;
 381         }
 382         p_data->p_payload_start += i_pes_header_size;
 383
 384         /* Now we can eventually put the PES packet in the decoder's
 385          * PES fifo */
 386         if( p_es->p_decoder_fifo != NULL )
 387         {
 388             input_DecodePES( p_es->p_decoder_fifo, p_pes );
 389         }
 390         else
 391         {
 392             intf_ErrMsg("No fifo to receive PES %p (who wrote this damn code ?)",
 393                         p_pes);
 394             p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 395         }
 396         p_pes = NULL;
 397     }
 398 #undef p_pes
 399 }
 400
 401 /*****************************************************************************
 402  * input_GatherPES:
 403  *****************************************************************************
 404  * Gather a PES packet.
 405  *****************************************************************************/
 406 void input_GatherPES( input_thread_t * p_input, data_packet_t * p_data,
 407                       es_descriptor_t * p_es,
 408                       boolean_t b_unit_start, boolean_t b_packet_lost )
 409 {
 410 #define p_pes (p_es->p_pes)
 411
 412     //intf_DbgMsg("PES-demultiplexing %p (%p)", p_ts_packet, p_pes);
 413
 414     /* If we lost data, insert a NULL data packet (philosophy : 0 is quite
 415      * often an escape sequence in decoders, so that should make them wait
 416      * for the next start code). */
 417     if( b_packet_lost || p_es->b_discontinuity )
 418     {
 419         input_NullPacket( p_input, p_es );
 420     }
 421
 422     if( b_unit_start && p_pes != NULL )
 423     {
 424         /* If the data packet contains the begining of a new PES packet, and
 425          * if we were reassembling a PES packet, then the PES should be
 426          * complete now, so parse its header and give it to the decoders. */
 427         input_ParsePES( p_input, p_es );
 428     }
 429
 430     if( !b_unit_start && p_pes == NULL )
 431     {
 432         /* Random access... */
 433         p_input->p_plugin->pf_delete_packet( p_input->p_method_data, p_data );
 434     }
 435     else
 436     {
 437         if( b_unit_start )
 438         {
 439             /* If we are at the beginning of a new PES packet, we must fetch
 440              * a new PES buffer to begin with the reassembly of this PES
 441              * packet. This is also here that we can synchronize with the
 442              * stream if we lost packets or if the decoder has just
 443              * started. */
 444             if( (p_pes = p_input->p_plugin->pf_new_pes( p_input->p_method_data ) ) == NULL )
 445             {
 446                 intf_ErrMsg("Out of memory");
 447                 p_input->b_error = 1;
 448                 return;
 449             }
 450             p_pes->i_rate = p_input->stream.control.i_rate;
 451             p_pes->p_first = p_data;
 452
 453             /* If the PES header fits in the first data packet, we can
 454              * already set p_gather->i_pes_real_size. */
 455             if( p_data->p_payload_end - p_data->p_payload_start
 456                     >= PES_HEADER_SIZE )
 457             {
 458                 p_es->i_pes_real_size =
 459                                 U16_AT(p_data->p_payload_start + 4) + 6;
 460             }
 461             else
 462             {
 463                 p_es->i_pes_real_size = 0;
 464             }
 465         }
 466         else
 467         {
 468             /* Update the relations between the data packets */
 469             p_es->p_last->p_next = p_data;
 470         }
 471
 472         p_es->p_last = p_data;
 473
 474         /* Size of the payload carried in the data packet */
 475         p_pes->i_pes_size += (p_data->p_payload_end
 476                                  - p_data->p_payload_start);
 477
 478         /* We can check if the packet is finished */
 479         if( p_pes->i_pes_size == p_es->i_pes_real_size )
 480         {
 481             /* The packet is finished, parse it */
 482             input_ParsePES( p_input, p_es );
 483         }
 484     }
 485 #undef p_pes
 486 }
 487
 488
 489 /*
 490  * PS Demultiplexing
 491  */
 492
 493 /*****************************************************************************
 494  * GetID: Get the ID of a stream
 495  *****************************************************************************/
 496 static u16 GetID( data_packet_t * p_data )
 497 {
 498     u16         i_id;
 499
 500     i_id = p_data->p_buffer[3];                                 /* stream_id */
 501     if( i_id == 0xBD )
 502     {
 503         /* stream_private_id */
 504         i_id |= p_data->p_buffer[ 9 + p_data->p_buffer[8] ] << 8;
 505     }
 506     return( i_id );
 507 }
 508
 509 /*****************************************************************************
 510  * DecodePSM: Decode the Program Stream Map information
 511  *****************************************************************************/
 512 static void DecodePSM( input_thread_t * p_input, data_packet_t * p_data )
 513 {
 514     stream_ps_data_t *  p_demux =
 515                  (stream_ps_data_t *)p_input->stream.p_demux_data;
 516     byte_t *            p_byte;
 517     byte_t *            p_end;
 518     int                 i;
 519     int                 i_new_es_number = 0;
 520
 521     intf_Msg("input info: Your stream contains Program Stream Map information");
 522     intf_Msg("input info: Please send a mail to <massiot@via.ecp.fr>");
 523
 524     if( p_data->p_payload_start + 10 > p_data->p_payload_end )
 525     {
 526         intf_ErrMsg( "PSM too short : packet corrupt" );
 527         return;
 528     }
 529
 530     if( p_demux->b_has_PSM
 531         && p_demux->i_PSM_version == (p_data->p_buffer[6] & 0x1F) )
 532     {
 533         /* Already got that one. */
 534         return;
 535     }
 536
 537     intf_DbgMsg( "Building PSM" );
 538     p_demux->b_has_PSM = 1;
 539     p_demux->i_PSM_version = p_data->p_buffer[6] & 0x1F;
 540
 541     /* Go to elementary_stream_map_length, jumping over
 542      * program_stream_info. */
 543     p_byte = p_data->p_payload_start + 10
 544               + U16_AT(&p_data->p_payload_start[8]);
 545     if( p_byte > p_data->p_payload_end )
 546     {
 547         intf_ErrMsg( "PSM too short : packet corrupt" );
 548         return;
 549     }
 550     /* This is the full size of the elementary_stream_map.
 551      * 2 == elementary_stream_map_length
 552      * Please note that CRC_32 is not included in the length. */
 553     p_end = p_byte + 2 + U16_AT(p_byte);
 554     p_byte += 2;
 555     if( p_end > p_data->p_payload_end )
 556     {
 557         intf_ErrMsg( "PSM too short : packet corrupt" );
 558         return;
 559     }
 560
 561     vlc_mutex_lock( &p_input->stream.stream_lock );
 562
 563     /* 4 == minimum useful size of a section */
 564     while( p_byte + 4 <= p_end )
 565     {
 566         es_descriptor_t *   p_es = NULL;
 567         u8                  i_stream_id = p_byte[1];
 568         /* FIXME: there will be a problem with private streams... (same
 569          * stream_id) */
 570
 571         /* Look for the ES in the ES table */
 572         for( i = i_new_es_number;
 573              i < p_input->stream.pp_programs[0]->i_es_number;
 574              i++ )
 575         {
 576             if( p_input->stream.pp_programs[0]->pp_es[i]->i_stream_id
 577                     == i_stream_id )
 578             {
 579                 p_es = p_input->stream.pp_programs[0]->pp_es[i];
 580                 if( p_es->i_type != p_byte[0] )
 581                 {
 582                     input_DelES( p_input, p_es );
 583                     p_es = NULL;
 584                 }
 585                 else
 586                 {
 587                     /* Move the ES to the beginning. */
 588                     p_input->stream.pp_programs[0]->pp_es[i]
 589                         = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
 590                     p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ]
 591                         = p_es;
 592                     i_new_es_number++;
 593                 }
 594                 break;
 595             }
 596         }
 597
 598         /* The goal is to have all the ES we have just read in the
 599          * beginning of the pp_es table, and all the others at the end,
 600          * so that we can close them more easily at the end. */
 601         if( p_es == NULL )
 602         {
 603             p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
 604                                 i_stream_id, 0 );
 605             p_es->i_type = p_byte[0];
 606             p_es->b_audio = ( p_es->i_type == MPEG1_AUDIO_ES
 607                               || p_es->i_type == MPEG2_AUDIO_ES
 608                               || p_es->i_type == AC3_AUDIO_ES
 609                               || p_es->i_type == LPCM_AUDIO_ES
 610                             );
 611
 612             /* input_AddES has inserted the new element at the end. */
 613             p_input->stream.pp_programs[0]->pp_es[
 614                 p_input->stream.pp_programs[0]->i_es_number ]
 615                 = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
 616             p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ] = p_es;
 617             i_new_es_number++;
 618         }
 619         p_byte += 4 + U16_AT(&p_byte[2]);
 620     }
 621
 622     /* Un-select the streams that are no longer parts of the program. */
 623     for( i = i_new_es_number;
 624          i < p_input->stream.pp_programs[0]->i_es_number;
 625          i++ )
 626     {
 627         /* We remove pp_es[i_new_es_member] and not pp_es[i] because the
 628          * list will be emptied starting from the end */
 629         input_DelES( p_input,
 630                      p_input->stream.pp_programs[0]->pp_es[i_new_es_number] );
 631     }
 632
 633 #ifdef STATS
 634     intf_Msg( "input info: The stream map after the PSM is now :" );
 635     input_DumpStream( p_input );
 636 #endif
 637
 638     vlc_mutex_unlock( &p_input->stream.stream_lock );
 639 }
 640
 641 /*****************************************************************************
 642  * input_ParsePS: read the PS header
 643  *****************************************************************************/
 644 es_descriptor_t * input_ParsePS( input_thread_t * p_input,
 645                                  data_packet_t * p_data )
 646 {
 647     u32                 i_code;
 648     es_descriptor_t *   p_es = NULL;
 649
 650     i_code = U32_AT( p_data->p_buffer );
 651     if( i_code > 0x1BC ) /* ES start code */
 652     {
 653         u16                 i_id;
 654         int                 i_dummy;
 655
 656         /* This is a PES packet. Find out if we want it or not. */
 657         i_id = GetID( p_data );
 658
 659         vlc_mutex_lock( &p_input->stream.stream_lock );
 660         if( p_input->stream.pp_programs[0]->b_is_ok )
 661         {
 662             /* Look only at the selected ES. */
 663             for( i_dummy = 0; i_dummy < p_input->stream.i_selected_es_number;
 664                  i_dummy++ )
 665             {
 666                 if( p_input->stream.pp_selected_es[i_dummy] != NULL
 667                     && p_input->stream.pp_selected_es[i_dummy]->i_id == i_id )
 668                 {
 669                     p_es = p_input->stream.pp_selected_es[i_dummy];
 670                     break;
 671                 }
 672             }
 673         }
 674         else
 675         {
 676             stream_ps_data_t * p_demux =
 677               (stream_ps_data_t *)p_input->stream.pp_programs[0]->p_demux_data;
 678
 679             /* Search all ES ; if not found -> AddES */
 680             p_es = input_FindES( p_input, i_id );
 681
 682             if( p_es == NULL && !p_demux->b_has_PSM )
 683             {
 684                 p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
 685                                     i_id, 0 );
 686                 if( p_es != NULL )
 687                 {
 688                     p_es->i_stream_id = p_data->p_buffer[3];
 689
 690                     /* Set stream type and auto-spawn. */
 691                     if( (i_id & 0xF0) == 0xE0 )
 692                     {
 693                         /* MPEG video */
 694                         p_es->i_type = MPEG2_VIDEO_ES;
 695 #ifdef AUTO_SPAWN
 696                         if( !p_input->stream.b_seekable )
 697                             input_SelectES( p_input, p_es );
 698 #endif
 699                     }
 700                     else if( (i_id & 0xE0) == 0xC0 )
 701                     {
 702                         /* MPEG audio */
 703                         p_es->i_type = MPEG2_AUDIO_ES;
 704                         p_es->b_audio = 1;
 705 #ifdef AUTO_SPAWN
 706                         if( !p_input->stream.b_seekable )
 707                         if( main_GetIntVariable( INPUT_DVD_CHANNEL_VAR, 0 )
 708                                 == (p_es->i_id & 0x1F) )
 709                         switch( main_GetIntVariable( INPUT_DVD_AUDIO_VAR, 0 ) )
 710                         {
 711                         case 0:
 712                             main_PutIntVariable( INPUT_DVD_CHANNEL_VAR,
 713                                                  REQUESTED_MPEG );
 714                         case REQUESTED_MPEG:
 715                             input_SelectES( p_input, p_es );
 716                         }
 717 #endif
 718                     }
 719                     else if( (i_id & 0xF0FF) == 0x80BD )
 720                     {
 721                         /* AC3 audio (0x80->0x8F) */
 722                         p_es->i_type = AC3_AUDIO_ES;
 723                         p_es->b_audio = 1;
 724 #ifdef AUTO_SPAWN
 725                         if( !p_input->stream.b_seekable )
 726                         if( main_GetIntVariable( INPUT_DVD_CHANNEL_VAR, 0 )
 727                                 == ((p_es->i_id & 0xF00) >> 8) )
 728                         switch( main_GetIntVariable( INPUT_DVD_AUDIO_VAR, 0 ) )
 729                         {
 730                         case 0:
 731                             main_PutIntVariable( INPUT_DVD_CHANNEL_VAR,
 732                                                  REQUESTED_AC3 );
 733                         case REQUESTED_AC3:
 734                             input_SelectES( p_input, p_es );
 735                         }
 736 #endif
 737                     }
 738                     else if( (i_id & 0xE0FF) == 0x20BD )
 739                     {
 740                         /* Subtitles video (0x20->0x3F) */
 741                         p_es->i_type = DVD_SPU_ES;
 742 #ifdef AUTO_SPAWN
 743                         if( main_GetIntVariable( INPUT_DVD_SUBTITLE_VAR, -1 )
 744                                 == ((p_es->i_id & 0x1F00) >> 8) )
 745                         {
 746                             if( !p_input->stream.b_seekable )
 747                                 input_SelectES( p_input, p_es );
 748                         }
 749 #endif
 750                     }
 751                     else if( (i_id & 0xF0FF) == 0xA0BD )
 752                     {
 753                         /* LPCM audio (0xA0->0xAF) */
 754                         p_es->i_type = LPCM_AUDIO_ES;
 755                         p_es->b_audio = 1;
 756                         /* FIXME : write the decoder */
 757                     }
 758                     else
 759                     {
 760                         p_es->i_type = UNKNOWN_ES;
 761                     }
 762                 }
 763             }
 764         } /* stream.b_is_ok */
 765         vlc_mutex_unlock( &p_input->stream.stream_lock );
 766     } /* i_code > 0xBC */
 767
 768     return( p_es );
 769 }
 770
 771 /*****************************************************************************
 772  * input_DemuxPS: first step of demultiplexing: the PS header
 773  *****************************************************************************/
 774 void input_DemuxPS( input_thread_t * p_input, data_packet_t * p_data )
 775 {
 776     u32                 i_code;
 777     boolean_t           b_trash = 0;
 778     es_descriptor_t *   p_es = NULL;
 779
 780     i_code = U32_AT( p_data->p_buffer );
 781     if( i_code <= 0x1BC )
 782     {
 783         switch( i_code )
 784         {
 785         case 0x1BA: /* PACK_START_CODE */
 786             {
 787                 /* Read the SCR. */
 788                 mtime_t         scr_time;
 789
 790                 if( (p_data->p_buffer[4] & 0xC0) == 0x40 )
 791                 {
 792                     /* MPEG-2 */
 793                     scr_time =
 794                          ((mtime_t)(p_data->p_buffer[4] & 0x38) << 27) |
 795                          ((mtime_t)(U32_AT(p_data->p_buffer + 4) & 0x03FFF800)
 796                                         << 4) |
 797                          ((mtime_t)(U32_AT(p_data->p_buffer + 6) & 0x03FFF800)
 798                                         >> 11);
 799                 }
 800                 else
 801                 {
 802                     /* MPEG-1 SCR is like PTS. */
 803                     scr_time =
 804                          ((mtime_t)(p_data->p_buffer[4] & 0x0E) << 29) |
 805                          (((mtime_t)U16_AT(p_data->p_buffer + 5) << 14)
 806                            - (1 << 14)) |
 807                          ((mtime_t)U16_AT(p_data->p_buffer + 7) >> 1);
 808                 }
 809                 /* Call the pace control. */
 810                 //intf_Msg("+%lld", scr_time);
 811                 input_ClockManageRef( p_input, p_input->stream.pp_programs[0],
 812                                       scr_time );
 813                 b_trash = 1;
 814             }
 815             break;
 816
 817         case 0x1BB: /* SYSTEM_START_CODE */
 818             b_trash = 1;                              /* Nothing interesting */
 819             break;
 820
 821         case 0x1BC: /* PROGRAM_STREAM_MAP_CODE */
 822             DecodePSM( p_input, p_data );
 823             b_trash = 1;
 824             break;
 825
 826         case 0x1B9: /* PROGRAM_END_CODE */
 827             b_trash = 1;
 828             break;
 829
 830         default:
 831             /* This should not happen */
 832             b_trash = 1;
 833             intf_WarnMsg( 1, "Unwanted packet received with start code %x",
 834                           i_code );
 835         }
 836     }
 837     else
 838     {
 839         p_es = input_ParsePS( p_input, p_data );
 840
 841         if( p_es != NULL && p_es->p_decoder_fifo != NULL )
 842         {
 843 #ifdef STATS
 844             p_es->c_packets++;
 845 #endif
 846             input_GatherPES( p_input, p_data, p_es, 1, 0 );
 847         }
 848         else
 849         {
 850             b_trash = 1;
 851         }
 852     }
 853
 854     /* Trash the packet if it has no payload or if it isn't selected */
 855     if( b_trash )
 856     {
 857         p_input->p_plugin->pf_delete_packet( p_input, p_data );
 858 #ifdef STATS
 859         p_input->c_packets_trashed++;
 860 #endif
 861     }
 862 }
 863
 864
 865 /*
 866  * TS Demultiplexing
 867  */
 868
 869 /*****************************************************************************
 870  * input_DemuxTS: first step of demultiplexing: the TS header
 871  *****************************************************************************/
 872 void input_DemuxTS( input_thread_t * p_input, data_packet_t * p_data )
 873 {
 874     int                 i_pid, i_dummy;
 875     boolean_t           b_adaptation;         /* Adaptation field is present */
 876     boolean_t           b_payload;                 /* Packet carries payload */
 877     boolean_t           b_unit_start;  /* A PSI or a PES start in the packet */
 878     boolean_t           b_trash = 0;             /* Is the packet unuseful ? */
 879     boolean_t           b_lost = 0;             /* Was there a packet loss ? */
 880     es_descriptor_t *   p_es = NULL;
 881     es_ts_data_t *      p_es_demux = NULL;
 882     pgrm_ts_data_t *    p_pgrm_demux = NULL;
 883
 884 #define p (p_data->p_buffer)
 885
 886     //intf_DbgMsg("input debug: TS-demultiplexing packet %p, pid %d",
 887     //            p_ts_packet, U16_AT(&p[1]) & 0x1fff);
 888
 889     /* Extract flags values from TS common header. */
 890     i_pid = U16_AT(&p[1]) & 0x1fff;
 891     b_unit_start = (p[1] & 0x40);
 892     b_adaptation = (p[3] & 0x20);
 893     b_payload = (p[3] & 0x10);
 894
 895     /* Find out the elementary stream. */
 896     vlc_mutex_lock( &p_input->stream.stream_lock );
 897     p_es = input_FindES( p_input, i_pid );
 898     vlc_mutex_unlock( &p_input->stream.stream_lock );
 899
 900     if( p_es == NULL || p_es->p_decoder_fifo == NULL )
 901     {
 902         /* Not selected. Just read the adaptation field for a PCR. */
 903         b_trash = 1;
 904     }
 905
 906     if( (p_es->p_decoder_fifo != NULL) || (p_pgrm_demux->i_pcr_pid == i_pid) )
 907     {
 908 #ifdef STATS
 909         p_es->c_packets++;
 910 #endif
 911
 912         /* Extract adaptation field information if any */
 913         if( !b_adaptation )
 914         {
 915             /* We don't have any adaptation_field, so payload starts
 916              * immediately after the 4 byte TS header */
 917             p_data->p_payload_start += 4;
 918         }
 919         else
 920         {
 921             /* p[4] is adaptation_field_length minus one */
 922             p_data->p_payload_start += 5 + p[4];
 923
 924             /* The adaptation field can be limited to the
 925              * adaptation_field_length byte, so that there is nothing to do:
 926              * skip this possibility */
 927             if( p[4] )
 928             {
 929                 /* If the packet has both adaptation_field and payload,
 930                  * adaptation_field cannot be more than 182 bytes long; if
 931                  * there is only an adaptation_field, it must fill the next
 932                  * 183 bytes. */
 933                 if( b_payload ? (p[4] > 182) : (p[4] != 183) )
 934                 {
 935                     intf_WarnMsg( 2,
 936                         "invalid TS adaptation field (%p)",
 937                         p_data );
 938                     p_data->b_discard_payload = 1;
 939 #ifdef STATS
 940                     p_es->c_invalid_packets++;
 941 #endif
 942                 }
 943
 944                 /* Now we are sure that the byte containing flags is present:
 945                  * read it */
 946                 else
 947                 {
 948                     /* discontinuity_indicator */
 949                     if( p[5] & 0x80 )
 950                     {
 951                         intf_WarnMsg( 2,
 952                             "discontinuity_indicator"
 953                             " encountered by TS demux (position read: %d,"
 954                             " saved: %d)",
 955                             p[5] & 0x80, p_es_demux->i_continuity_counter );
 956
 957                         /* If the PID carries the PCR, there will be a system
 958                          * time-based discontinuity. We let the PCR decoder
 959                          * handle that. */
 960                         p_es->p_pgrm->b_discontinuity = 1;
 961
 962                         /* There also may be a continuity_counter
 963                          * discontinuity: resynchronise our counter with
 964                          * the one of the stream. */
 965                         p_es_demux->i_continuity_counter = (p[3] & 0x0f) - 1;
 966                     }
 967
 968                     /* If this is a PCR_PID, and this TS packet contains a
 969                      * PCR, we pass it along to the PCR decoder. */
 970                     if( (p_pgrm_demux->i_pcr_pid == i_pid) && (p[5] & 0x10) )
 971                     {
 972                         /* There should be a PCR field in the packet, check
 973                          * if the adaptation field is long enough to carry
 974                          * it. */
 975                         if( p[4] >= 7 )
 976                         {
 977                             /* Read the PCR. */
 978                             mtime_t     pcr_time;
 979                             pcr_time =
 980                                     ( (mtime_t)U32_AT((u32*)&p[6]) << 1 )
 981                                       | ( p[10] >> 7 );
 982                             /* Call the pace control. */
 983                             input_ClockManageRef( p_input, p_es->p_pgrm,
 984                                                   pcr_time );
 985                         }
 986                     } /* PCR ? */
 987                 } /* valid TS adaptation field ? */
 988             } /* length > 0 */
 989         } /* has adaptation field */
 990
 991         /* Check the continuity of the stream. */
 992         i_dummy = ((p[3] & 0x0f) - p_es_demux->i_continuity_counter) & 0x0f;
 993         if( i_dummy == 1 )
 994         {
 995             /* Everything is ok, just increase our counter */
 996             p_es_demux->i_continuity_counter++;
 997         }
 998         else
 999         {
1000             if( !b_payload && i_dummy == 0 )
1001             {
1002                 /* This is a packet without payload, this is allowed by the
1003                  * draft. As there is nothing interesting in this packet
1004                  * (except PCR that have already been handled), we can trash
1005                  * the packet. */
1006                 intf_WarnMsg( 1,
1007                               "Packet without payload received by TS demux" );
1008                 b_trash = 1;
1009             }
1010             else if( i_dummy <= 0 )
1011             {
1012                 /* FIXME: this can never happen, can it ? --Meuuh */
1013                 /* Duplicate packet: mark it as being to be trashed. */
1014                 intf_WarnMsg( 1, "Duplicate packet received by TS demux" );
1015                 b_trash = 1;
1016             }
1017             else if( p_es_demux->i_continuity_counter == 0xFF )
1018             {
1019                 /* This means that the packet is the first one we receive for
1020                  * this ES since the continuity counter ranges between 0 and
1021                  * 0x0F excepts when it has been initialized by the input:
1022                  * init the counter to the correct value. */
1023                 intf_DbgMsg( "First packet for PID %d received by TS demux",
1024                              p_es->i_id );
1025                 p_es_demux->i_continuity_counter = (p[3] & 0x0f);
1026             }
1027             else
1028             {
1029                 /* This can indicate that we missed a packet or that the
1030                  * continuity_counter wrapped and we received a dup packet:
1031                  * as we don't know, do as if we missed a packet to be sure
1032                  * to recover from this situation */
1033                 intf_WarnMsg( 2,
1034                            "Packet lost by TS demux: current %d, packet %d",
1035                            p_es_demux->i_continuity_counter & 0x0f,
1036                            p[3] & 0x0f );
1037                 b_lost = 1;
1038                 p_es_demux->i_continuity_counter = p[3] & 0x0f;
1039             } /* not continuous */
1040         } /* continuity */
1041     } /* if selected or PCR */
1042
1043     /* Trash the packet if it has no payload or if it isn't selected */
1044     if( b_trash )
1045     {
1046         p_input->p_plugin->pf_delete_packet( p_input, p_data );
1047 #ifdef STATS
1048         p_input->c_packets_trashed++;
1049 #endif
1050     }
1051     else
1052     {
1053         if( p_es_demux->b_psi )
1054         {
1055             /* The payload contains PSI tables */
1056 #if 0
1057             /* FIXME ! write the PSI decoder :p */
1058             input_DemuxPSI( p_input, p_data, p_es,
1059                             b_unit_start, b_lost );
1060 #endif
1061         }
1062         else
1063         {
1064             /* The payload carries a PES stream */
1065             if( b_unit_start )
1066             input_GatherPES( p_input, p_data, p_es, b_unit_start, b_lost );
1067         }
1068     }
1069
1070 #undef p
1071 }