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 1.23 2000/12/29 14:04:59 sam 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 #include <netinet/in.h>
  31
  32 #include "config.h"
  33 #include "common.h"
  34 #include "threads.h"
  35 #include "mtime.h"
  36
  37 #include "intf_msg.h"
  38
  39 #include "stream_control.h"
  40 #include "input_ext-intf.h"
  41 #include "input_ext-dec.h"
  42
  43 #include "input.h"
  44 #include "mpeg_system.h"
  45 #include "input_dec.h"
  46
  47 #include "main.h"                           /* AC3/MPEG channel, SPU channel */
  48
  49 /*****************************************************************************
  50  * Local prototypes
  51  *****************************************************************************/
  52
  53
  54 /*
  55  * PES Packet management
  56  */
  57
  58 /*****************************************************************************
  59  * MoveChunk
  60  *****************************************************************************
  61  * Small utility function used to parse discontinuous headers safely. Copies
  62  * i_buf_len bytes of data to a buffer and returns the size copied.
  63  * This is a variation on the theme of input_ext-dec.h:GetChunk().
  64  *****************************************************************************/
  65 static __inline__ size_t MoveChunk( byte_t * p_dest,
  66                                     data_packet_t ** pp_data_src,
  67                                     byte_t ** pp_src,
  68                                     size_t i_buf_len )
  69 {
  70     ptrdiff_t           i_available;
  71
  72     if( (i_available = (*pp_data_src)->p_payload_end - *pp_src)
  73             >= i_buf_len )
  74     {
  75         if( p_dest != NULL )
  76             memcpy( p_dest, *pp_src, i_buf_len );
  77         *pp_src += i_buf_len;
  78         return( i_buf_len );
  79     }
  80     else
  81     {
  82         size_t          i_init_len = i_buf_len;
  83
  84         do
  85         {
  86             if( p_dest != NULL )
  87                 memcpy( p_dest, *pp_src, i_available );
  88             *pp_data_src = (*pp_data_src)->p_next;
  89             i_buf_len -= i_available;
  90             p_dest += i_available;
  91             if( *pp_data_src == NULL )
  92             {
  93                 *pp_src = NULL;
  94                 return( i_init_len - i_buf_len );
  95             }
  96             *pp_src = (*pp_data_src)->p_payload_start;
  97         }
  98         while( (i_available = (*pp_data_src)->p_payload_end - *pp_src)
  99                 <= i_buf_len );
 100
 101         if( i_buf_len )
 102         {
 103             if( p_dest != NULL )
 104                 memcpy( p_dest, *pp_src, i_buf_len );
 105             *pp_src += i_buf_len;
 106         }
 107         return( i_init_len );
 108     }
 109 }
 110
 111 /*****************************************************************************
 112  * input_ParsePES
 113  *****************************************************************************
 114  * Parse a finished PES packet and analyze its header.
 115  *****************************************************************************/
 116 #define PES_HEADER_SIZE     7
 117 void input_ParsePES( input_thread_t * p_input, es_descriptor_t * p_es )
 118 {
 119     data_packet_t * p_data;
 120     byte_t *        p_byte;
 121     byte_t          p_header[PES_HEADER_SIZE];
 122     int             i_done;
 123
 124 #define p_pes (p_es->p_pes)
 125
 126     //intf_DbgMsg("End of PES packet %p", p_pes);
 127
 128     /* Parse the header. The header has a variable length, but in order
 129      * to improve the algorithm, we will read the 14 bytes we may be
 130      * interested in */
 131     p_data = p_pes->p_first;
 132     p_byte = p_data->p_payload_start;
 133     i_done = 0;
 134
 135     if( MoveChunk( p_header, &p_data, &p_byte, PES_HEADER_SIZE )
 136             != PES_HEADER_SIZE )
 137     {
 138         intf_WarnMsg( 3, "PES packet too short to have a header" );
 139         p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 140         p_pes = NULL;
 141         return;
 142     }
 143
 144     /* Get the PES size if defined */
 145     p_es->i_pes_real_size = U16_AT(p_header + 4) + 6;
 146
 147     /* First read the 6 header bytes common to all PES packets:
 148      * use them to test the PES validity */
 149     if( (p_header[0] || p_header[1] || (p_header[2] != 1)) )
 150     {
 151         /* packet_start_code_prefix != 0x000001 */
 152         intf_ErrMsg( "PES packet doesn't start with 0x000001 : data loss" );
 153         p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 154         p_pes = NULL;
 155     }
 156     else
 157     {
 158         int i_pes_header_size, i_payload_size;
 159
 160         if ( p_es->i_pes_real_size &&
 161              (p_es->i_pes_real_size != p_pes->i_pes_size) )
 162         {
 163             /* PES_packet_length is set and != total received payload */
 164             /* Warn the decoder that the data may be corrupt. */
 165             intf_WarnMsg( 3, "PES sizes do not match : packet corrupted" );
 166             p_pes->b_messed_up = 1;
 167         }
 168
 169         switch( p_es->i_stream_id )
 170         {
 171         case 0xBC:  /* Program stream map */
 172         case 0xBE:  /* Padding */
 173         case 0xBF:  /* Private stream 2 */
 174         case 0xB0:  /* ECM */
 175         case 0xB1:  /* EMM */
 176         case 0xFF:  /* Program stream directory */
 177         case 0xF2:  /* DSMCC stream */
 178         case 0xF8:  /* ITU-T H.222.1 type E stream */
 179             /* The payload begins immediately after the 6 bytes header, so
 180              * we have finished with the parsing */
 181             i_pes_header_size = 6;
 182             break;
 183
 184         default:
 185             if( (p_header[6] & 0xC0) == 0x80 )
 186             {
 187                 /* MPEG-2 : the PES header contains at least 3 more bytes. */
 188                 size_t      i_max_len;
 189                 boolean_t   b_has_pts, b_has_dts;
 190                 byte_t      p_full_header[12];
 191
 192                 p_pes->b_data_alignment = p_header[6] & 0x04;
 193
 194                 i_max_len = MoveChunk( p_full_header, &p_data, &p_byte, 12 );
 195                 if( i_max_len < 2 )
 196                 {
 197                     intf_WarnMsg( 3,
 198                             "PES packet too short to have a MPEG-2 header" );
 199                     p_input->p_plugin->pf_delete_pes( p_input->p_method_data,
 200                                                       p_pes );
 201                     p_pes = NULL;
 202                     return;
 203                 }
 204
 205                 b_has_pts = p_full_header[0] & 0x80;
 206                 b_has_dts = p_full_header[0] & 0x40;
 207                 i_pes_header_size = p_full_header[1] + 9;
 208
 209                 /* Now parse the optional header extensions */
 210                 if( b_has_pts )
 211                 {
 212                     if( i_max_len < 7 )
 213                     {
 214                         intf_WarnMsg( 3,
 215                             "PES packet too short to have a MPEG-2 header" );
 216                         p_input->p_plugin->pf_delete_pes(
 217                                                       p_input->p_method_data,
 218                                                       p_pes );
 219                         p_pes = NULL;
 220                         return;
 221                     }
 222                     p_pes->i_pts =
 223                     ( ((mtime_t)(p_full_header[2] & 0x0E) << 29) |
 224                       (((mtime_t)U16_AT(p_full_header + 3) << 14) - (1 << 14)) |
 225                       ((mtime_t)U16_AT(p_full_header + 5) >> 1) ) * 300;
 226                     p_pes->i_pts /= 27;
 227
 228                     if( b_has_dts )
 229                     {
 230                         if( i_max_len < 12 )
 231                         {
 232                             intf_WarnMsg( 3,
 233                               "PES packet too short to have a MPEG-2 header" );
 234                             p_input->p_plugin->pf_delete_pes(
 235                                     p_input->p_method_data,
 236                                     p_pes );
 237                             p_pes = NULL;
 238                             return;
 239                         }
 240                         p_pes->i_dts =
 241                         ( ((mtime_t)(p_full_header[7] & 0x0E) << 29) |
 242                           (((mtime_t)U16_AT(p_full_header + 8) << 14)
 243                                 - (1 << 14)) |
 244                           ((mtime_t)U16_AT(p_full_header + 10) >> 1) ) * 300;
 245                         p_pes->i_dts /= 27;
 246                     }
 247                 }
 248             }
 249             else
 250             {
 251                 /* Probably MPEG-1 */
 252                 boolean_t       b_has_pts, b_has_dts;
 253
 254                 i_pes_header_size = 6;
 255                 p_data = p_pes->p_first;
 256                 p_byte = p_data->p_payload_start;
 257                 /* Cannot fail because the previous one succeeded. */
 258                 MoveChunk( NULL, &p_data, &p_byte, 6 );
 259
 260                 while( *p_byte == 0xFF && i_pes_header_size < 22 )
 261                 {
 262                     i_pes_header_size++;
 263                     if( MoveChunk( NULL, &p_data, &p_byte, 1 ) != 1 )
 264                     {
 265                         intf_WarnMsg( 3,
 266                             "PES packet too short to have a MPEG-1 header" );
 267                         p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 268                         p_pes = NULL;
 269                         return;
 270                     }
 271                 }
 272                 if( i_pes_header_size == 22 )
 273                 {
 274                     intf_ErrMsg( "Too much MPEG-1 stuffing" );
 275                     p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 276                     p_pes = NULL;
 277                     return;
 278                 }
 279
 280                 if( (*p_byte & 0xC0) == 0x40 )
 281                 {
 282                     /* Don't ask why... --Meuuh */
 283                     /* Erm... why ? --Sam */
 284                     /* Well... According to the recommendation, it is for
 285                      * STD_buffer_scale and STD_buffer_size. --Meuuh */
 286                     i_pes_header_size += 2;
 287                     if( MoveChunk( NULL, &p_data, &p_byte, 2 ) != 2 )
 288                     {
 289                         intf_WarnMsg( 3,
 290                             "PES packet too short to have a MPEG-1 header" );
 291                         p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 292                         p_pes = NULL;
 293                         return;
 294                     }
 295                 }
 296
 297                 i_pes_header_size++;
 298
 299                 b_has_pts = *p_byte & 0x20;
 300                 b_has_dts = *p_byte & 0x10;
 301
 302                 if( b_has_pts )
 303                 {
 304                     byte_t      p_ts[5];
 305
 306                     i_pes_header_size += 4;
 307                     if( MoveChunk( p_ts, &p_data, &p_byte, 5 ) != 5 )
 308                     {
 309                         intf_WarnMsg( 3,
 310                             "PES packet too short to have a MPEG-1 header" );
 311                         p_input->p_plugin->pf_delete_pes(
 312                                             p_input->p_method_data, p_pes );
 313                         p_pes = NULL;
 314                         return;
 315                     }
 316
 317                     p_pes->i_pts =
 318                       ( ((mtime_t)(p_ts[0] & 0x0E) << 29) |
 319                         (((mtime_t)U16_AT(p_ts + 1) << 14) - (1 << 14)) |
 320                         ((mtime_t)U16_AT(p_ts + 3) >> 1) ) * 300;
 321                     p_pes->i_pts /= 27;
 322
 323                     if( b_has_dts )
 324                     {
 325                         i_pes_header_size += 5;
 326                         if( MoveChunk( p_ts, &p_data, &p_byte, 5 ) != 5 )
 327                         {
 328                             intf_WarnMsg( 3,
 329                               "PES packet too short to have a MPEG-1 header" );
 330                             p_input->p_plugin->pf_delete_pes(
 331                                     p_input->p_method_data, p_pes );
 332                             p_pes = NULL;
 333                             return;
 334                         }
 335
 336                         p_pes->i_dts =
 337                             ( ((mtime_t)(p_ts[0] & 0x0E) << 29) |
 338                               (((mtime_t)U16_AT(p_ts + 1) << 14) - (1 << 14)) |
 339                               ((mtime_t)U16_AT(p_ts + 3) >> 1) ) * 300;
 340                         p_pes->i_dts /= 27;
 341                     }
 342                 }
 343             }
 344
 345             /* PTS management */
 346             if( p_pes->i_pts )
 347             {
 348                 //intf_Msg("%lld", p_pes->i_pts);
 349                 switch( p_es->p_pgrm->i_synchro_state )
 350                 {
 351                 case SYNCHRO_NOT_STARTED:
 352                 case SYNCHRO_START:
 353                     p_pes->i_pts = p_pes->i_dts = 0;
 354                     break;
 355
 356                 case SYNCHRO_REINIT: /* We skip a PES | Why ?? --Meuuh */
 357                     p_pes->i_pts = p_pes->i_dts = 0;
 358                     p_es->p_pgrm->i_synchro_state = SYNCHRO_START;
 359                     break;
 360
 361                 case SYNCHRO_OK:
 362                     p_pes->i_pts += p_es->p_pgrm->delta_cr
 363                                          + p_es->p_pgrm->delta_absolute
 364                                          + DEFAULT_PTS_DELAY;
 365                     if( p_pes->i_dts )
 366                     {
 367                         p_pes->i_dts += p_es->p_pgrm->delta_cr
 368                                              + p_es->p_pgrm->delta_absolute
 369                                              + DEFAULT_PTS_DELAY;
 370                     }
 371                     break;
 372                 }
 373             }
 374             break;
 375         }
 376
 377         if( p_es->i_stream_id == 0xbd )
 378         {
 379             /* With private stream 1, the first byte of the payload
 380              * is a stream_private_id, so skip it. */
 381             i_pes_header_size++;
 382         }
 383
 384         /* Now we've parsed the header, we just have to indicate in some
 385          * specific data packets where the PES payload begins (renumber
 386          * p_payload_start), so that the decoders can find the beginning
 387          * of their data right out of the box. */
 388         p_data = p_pes->p_first;
 389         i_payload_size = p_data->p_payload_end
 390                                  - p_data->p_payload_start;
 391         while( i_pes_header_size > i_payload_size )
 392         {
 393             /* These packets are entirely filled by the PES header. */
 394             i_pes_header_size -= i_payload_size;
 395             p_data->p_payload_start = p_data->p_payload_end;
 396             /* Go to the next data packet. */
 397             if( (p_data = p_data->p_next) == NULL )
 398             {
 399                 intf_ErrMsg( "PES header bigger than payload" );
 400                 p_input->p_plugin->pf_delete_pes( p_input->p_method_data,
 401                                                   p_pes );
 402                 p_pes = NULL;
 403                 return;
 404             }
 405             i_payload_size = p_data->p_payload_end
 406                                  - p_data->p_payload_start;
 407         }
 408         /* This last packet is partly header, partly payload. */
 409         if( i_payload_size < i_pes_header_size )
 410         {
 411             intf_ErrMsg( "PES header bigger than payload" );
 412             p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 413             p_pes = NULL;
 414             return;
 415         }
 416         p_data->p_payload_start += i_pes_header_size;
 417
 418         /* Now we can eventually put the PES packet in the decoder's
 419          * PES fifo */
 420         if( p_es->p_decoder_fifo != NULL )
 421         {
 422             input_DecodePES( p_es->p_decoder_fifo, p_pes );
 423         }
 424         else
 425         {
 426             intf_ErrMsg("No fifo to receive PES %p (who wrote this damn code ?)",
 427                         p_pes);
 428             p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
 429         }
 430         p_pes = NULL;
 431     }
 432 #undef p_pes
 433 }
 434
 435 /*****************************************************************************
 436  * input_GatherPES:
 437  *****************************************************************************
 438  * Gather a PES packet.
 439  *****************************************************************************/
 440 void input_GatherPES( input_thread_t * p_input, data_packet_t * p_data,
 441                       es_descriptor_t * p_es,
 442                       boolean_t b_unit_start, boolean_t b_packet_lost )
 443 {
 444 #define p_pes (p_es->p_pes)
 445
 446     //intf_DbgMsg("PES-demultiplexing %p (%p)", p_ts_packet, p_pes);
 447
 448     /* If we lost data, insert a NULL data packet (philosophy : 0 is quite
 449      * often an escape sequence in decoders, so that should make them wait
 450      * for the next start code). */
 451     if( b_packet_lost || p_es->b_discontinuity )
 452     {
 453         data_packet_t *             p_pad_data;
 454
 455         if( (p_pad_data = p_input->p_plugin->pf_new_packet(
 456                                             p_input->p_method_data,
 457                                             PADDING_PACKET_SIZE )) == NULL )
 458         {
 459             intf_ErrMsg("Out of memory");
 460             p_input->b_error = 1;
 461             return;
 462         }
 463         memset( p_data->p_buffer, 0, PADDING_PACKET_SIZE );
 464         p_pad_data->b_discard_payload = 1;
 465
 466         if( p_pes != NULL )
 467         {
 468             p_pes->b_messed_up = p_pes->b_discontinuity = 1;
 469             input_GatherPES( p_input, p_pad_data, p_es, 0, 0 );
 470         }
 471         else
 472         {
 473             if( (p_pes = p_input->p_plugin->pf_new_pes(
 474                                             p_input->p_method_data )) == NULL )
 475             {
 476                 intf_ErrMsg("Out of memory");
 477                 p_input->b_error = 1;
 478                 return;
 479             }
 480
 481             p_pes->p_first = p_pad_data;
 482             p_pes->b_messed_up = p_pes->b_discontinuity = 1;
 483             input_DecodePES( p_es->p_decoder_fifo, p_pes );
 484         }
 485
 486         p_es->b_discontinuity = 0;
 487     }
 488
 489     if( b_unit_start && p_pes != NULL )
 490     {
 491         /* If the TS packet contains the begining of a new PES packet, and
 492          * if we were reassembling a PES packet, then the PES should be
 493          * complete now, so parse its header and give it to the decoders. */
 494         input_ParsePES( p_input, p_es );
 495     }
 496
 497     if( !b_unit_start && p_pes == NULL )
 498     {
 499         /* Random access... */
 500         p_input->p_plugin->pf_delete_packet( p_input->p_method_data, p_data );
 501     }
 502     else
 503     {
 504         if( b_unit_start )
 505         {
 506             /* If we are at the beginning of a new PES packet, we must fetch
 507              * a new PES buffer to begin with the reassembly of this PES
 508              * packet. This is also here that we can synchronize with the
 509              * stream if we lost packets or if the decoder has just
 510              * started. */
 511             if( (p_pes = p_input->p_plugin->pf_new_pes( p_input->p_method_data ) ) == NULL )
 512             {
 513                 intf_ErrMsg("Out of memory");
 514                 p_input->b_error = 1;
 515                 return;
 516             }
 517             //intf_DbgMsg("New PES packet %p (first data: %p)", p_pes, p_data);
 518             p_pes->p_first = p_data;
 519
 520             /* If the PES header fits in the first data packet, we can
 521              * already set p_gather->i_pes_real_size. */
 522             if( p_data->p_payload_end - p_data->p_payload_start
 523                     >= PES_HEADER_SIZE )
 524             {
 525                 p_es->i_pes_real_size =
 526                                 U16_AT(p_data->p_payload_start + 4) + 6;
 527             }
 528             else
 529             {
 530                 p_es->i_pes_real_size = 0;
 531             }
 532         }
 533         else
 534         {
 535             /* Update the relations between the data packets */
 536             p_es->p_last->p_next = p_data;
 537         }
 538
 539         p_data->p_next = NULL;
 540         p_es->p_last = p_data;
 541
 542         /* Size of the payload carried in the data packet */
 543         p_pes->i_pes_size += (p_data->p_payload_end
 544                                  - p_data->p_payload_start);
 545
 546         /* We can check if the packet is finished */
 547         if( p_pes->i_pes_size == p_es->i_pes_real_size )
 548         {
 549             /* The packet is finished, parse it */
 550             input_ParsePES( p_input, p_es );
 551         }
 552     }
 553 #undef p_pes
 554 }
 555
 556
 557 /*
 558  * Pace control
 559  */
 560
 561 /*
 562  *   DISCUSSION : SYNCHRONIZATION METHOD
 563  *
 564  *   In some cases we can impose the pace of reading (when reading from a
 565  *   file or a pipe), and for the synchronization we simply sleep() until
 566  *   it is time to deliver the packet to the decoders. When reading from
 567  *   the network, we must be read at the same pace as the server writes,
 568  *   otherwise the kernel's buffer will trash packets. The risk is now to
 569  *   overflow the input buffers in case the server goes too fast, that is
 570  *   why we do these calculations :
 571  *
 572  *   We compute an average for the pcr because we want to eliminate the
 573  *   network jitter and keep the low frequency variations. The average is
 574  *   in fact a low pass filter and the jitter is a high frequency signal
 575  *   that is why it is eliminated by the filter/average.
 576  *
 577  *   The low frequency variations enable us to synchronize the client clock
 578  *   with the server clock because they represent the time variation between
 579  *   the 2 clocks. Those variations (ie the filtered pcr) are used to compute
 580  *   the presentation dates for the audio and video frames. With those dates
 581  *   we can decode (or trash) the MPEG2 stream at "exactly" the same rate
 582  *   as it is sent by the server and so we keep the synchronization between
 583  *   the server and the client.
 584  *
 585  *   It is a very important matter if you want to avoid underflow or overflow
 586  *   in all the FIFOs, but it may be not enough.
 587  */
 588
 589 /*****************************************************************************
 590  * Constants
 591  *****************************************************************************/
 592
 593 /* Maximum number of samples used to compute the dynamic average value,
 594  * it is also the maximum of c_average_count in pgrm_ts_data_t.
 595  * We use the following formula :
 596  * new_average = (old_average * c_average + new_sample_value) / (c_average +1) */
 597 #define CR_MAX_AVERAGE_COUNTER 40
 598
 599 /* Maximum gap allowed between two CRs. */
 600 #define CR_MAX_GAP 1000000
 601
 602 /*****************************************************************************
 603  * CRReInit : Reinitialize the clock reference
 604  *****************************************************************************/
 605 static void CRReInit( pgrm_descriptor_t * p_pgrm )
 606 {
 607     p_pgrm->delta_cr        = 0;
 608     p_pgrm->last_cr         = 0;
 609     p_pgrm->c_average_count = 0;
 610 }
 611
 612 /* FIXME: find a better name */
 613 /*****************************************************************************
 614  * CRDecode : Decode a clock reference
 615  *****************************************************************************/
 616 static void CRDecode( input_thread_t * p_input, pgrm_descriptor_t * p_pgrm,
 617                       mtime_t cr_time )
 618 {
 619     if( p_pgrm->i_synchro_state != SYNCHRO_OK )
 620     {
 621         switch( p_pgrm->i_synchro_state )
 622         {
 623         case SYNCHRO_START:
 624             p_pgrm->delta_absolute = mdate() - cr_time;
 625             p_pgrm->i_synchro_state = SYNCHRO_OK;
 626             break;
 627
 628         case SYNCHRO_NOT_STARTED:
 629             p_pgrm->i_synchro_state = SYNCHRO_START;
 630             break;
 631
 632         default:
 633             break;
 634         }
 635     }
 636     else
 637     {
 638         if( p_pgrm->b_discontinuity ||
 639             ( p_pgrm->last_cr != 0 &&
 640                   (    (p_pgrm->last_cr - cr_time) > CR_MAX_GAP
 641                     || (p_pgrm->last_cr - cr_time) < - CR_MAX_GAP ) ) )
 642         {
 643             int i_es;
 644
 645             /* Stream discontinuity. */
 646             intf_WarnMsg( 3, "CR re-initialiazed" );
 647             CRReInit( p_pgrm );
 648             p_pgrm->i_synchro_state = SYNCHRO_REINIT;
 649             p_pgrm->b_discontinuity = 0;
 650
 651             /* Warn all the elementary streams */
 652             for( i_es = 0; i_es < p_pgrm->i_es_number; i_es++ )
 653             {
 654                 p_pgrm->pp_es[i_es]->b_discontinuity = 1;
 655             }
 656         }
 657         p_pgrm->last_cr = cr_time;
 658
 659         if( p_input->stream.b_pace_control )
 660         {
 661             /* Wait a while before delivering the packets to the decoder. */
 662             mwait( cr_time + p_pgrm->delta_absolute );
 663         }
 664         else
 665         {
 666             mtime_t                 sys_time, delta_cr;
 667
 668             sys_time = mdate();
 669             delta_cr = sys_time - cr_time;
 670
 671             if( p_pgrm->c_average_count == CR_MAX_AVERAGE_COUNTER )
 672             {
 673                 p_pgrm->delta_cr = ( delta_cr + (p_pgrm->delta_cr
 674                                               * (CR_MAX_AVERAGE_COUNTER - 1)) )
 675                                      / CR_MAX_AVERAGE_COUNTER;
 676             }
 677             else
 678             {
 679                 p_pgrm->delta_cr = ( delta_cr + (p_pgrm->delta_cr
 680                                               * p_pgrm->c_average_count) )
 681                                      / ( p_pgrm->c_average_count + 1 );
 682                 p_pgrm->c_average_count++;
 683             }
 684         }
 685     }
 686 }
 687
 688
 689 /*
 690  * PS Demultiplexing
 691  */
 692
 693 /*****************************************************************************
 694  * GetID: Get the ID of a stream
 695  *****************************************************************************/
 696 static u16 GetID( data_packet_t * p_data )
 697 {
 698     u16         i_id;
 699
 700     i_id = p_data->p_buffer[3];                                 /* stream_id */
 701     if( i_id == 0xBD )
 702     {
 703         /* stream_private_id */
 704         i_id |= p_data->p_buffer[ 9 + p_data->p_buffer[8] ] << 8;
 705     }
 706     return( i_id );
 707 }
 708
 709 /*****************************************************************************
 710  * DecodePSM: Decode the Program Stream Map information
 711  *****************************************************************************/
 712 static void DecodePSM( input_thread_t * p_input, data_packet_t * p_data )
 713 {
 714     stream_ps_data_t *  p_demux =
 715                  (stream_ps_data_t *)p_input->stream.p_demux_data;
 716     byte_t *            p_byte;
 717     byte_t *            p_end;
 718     int                 i;
 719     int                 i_new_es_number = 0;
 720
 721     intf_Msg("input info: Your stream contains Program Stream Map information");
 722     intf_Msg("input info: Please send a mail to <massiot@via.ecp.fr>");
 723
 724     if( p_data->p_payload_start + 10 > p_data->p_payload_end )
 725     {
 726         intf_ErrMsg( "PSM too short : packet corrupt" );
 727         return;
 728     }
 729
 730     if( p_demux->b_has_PSM
 731         && p_demux->i_PSM_version == (p_data->p_buffer[6] & 0x1F) )
 732     {
 733         /* Already got that one. */
 734         return;
 735     }
 736
 737     intf_DbgMsg( "Building PSM" );
 738     p_demux->b_has_PSM = 1;
 739     p_demux->i_PSM_version = p_data->p_buffer[6] & 0x1F;
 740
 741     /* Go to elementary_stream_map_length, jumping over
 742      * program_stream_info. */
 743     p_byte = p_data->p_payload_start + 10
 744               + U16_AT(&p_data->p_payload_start[8]);
 745     if( p_byte > p_data->p_payload_end )
 746     {
 747         intf_ErrMsg( "PSM too short : packet corrupt" );
 748         return;
 749     }
 750     /* This is the full size of the elementary_stream_map.
 751      * 2 == elementary_stream_map_length
 752      * Please note that CRC_32 is not included in the length. */
 753     p_end = p_byte + 2 + U16_AT(p_byte);
 754     p_byte += 2;
 755     if( p_end > p_data->p_payload_end )
 756     {
 757         intf_ErrMsg( "PSM too short : packet corrupt" );
 758         return;
 759     }
 760
 761     vlc_mutex_lock( &p_input->stream.stream_lock );
 762
 763     /* 4 == minimum useful size of a section */
 764     while( p_byte + 4 <= p_end )
 765     {
 766         es_descriptor_t *   p_es = NULL;
 767         u8                  i_stream_id = p_byte[1];
 768         /* FIXME: there will be a problem with private streams... (same
 769          * stream_id) */
 770
 771         /* Look for the ES in the ES table */
 772         for( i = i_new_es_number;
 773              i < p_input->stream.pp_programs[0]->i_es_number;
 774              i++ )
 775         {
 776             if( p_input->stream.pp_programs[0]->pp_es[i]->i_stream_id
 777                     == i_stream_id )
 778             {
 779                 p_es = p_input->stream.pp_programs[0]->pp_es[i];
 780                 if( p_es->i_type != p_byte[0] )
 781                 {
 782                     input_DelES( p_input, p_es );
 783                     p_es = NULL;
 784                 }
 785                 else
 786                 {
 787                     /* Move the ES to the beginning. */
 788                     p_input->stream.pp_programs[0]->pp_es[i]
 789                         = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
 790                     p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ]
 791                         = p_es;
 792                     i_new_es_number++;
 793                 }
 794                 break;
 795             }
 796         }
 797
 798         /* The goal is to have all the ES we have just read in the
 799          * beginning of the pp_es table, and all the others at the end,
 800          * so that we can close them more easily at the end. */
 801         if( p_es == NULL )
 802         {
 803             p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
 804                                 i_stream_id, 0 );
 805             p_es->i_type = p_byte[0];
 806
 807             /* input_AddES has inserted the new element at the end. */
 808             p_input->stream.pp_programs[0]->pp_es[
 809                 p_input->stream.pp_programs[0]->i_es_number ]
 810                 = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
 811             p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ] = p_es;
 812             i_new_es_number++;
 813         }
 814         p_byte += 4 + U16_AT(&p_byte[2]);
 815     }
 816
 817     /* Un-select the streams that are no longer parts of the program. */
 818     for( i = i_new_es_number;
 819          i < p_input->stream.pp_programs[0]->i_es_number;
 820          i++ )
 821     {
 822         input_DelES( p_input,
 823                      p_input->stream.pp_programs[0]->pp_es[i_new_es_number] );
 824         /* Yes, I wrote *i_new_es_number* */
 825     }
 826
 827 #ifdef STATS
 828     intf_Msg( "input info: The stream map after the PSM is now :" );
 829     input_DumpStream( p_input );
 830 #endif
 831
 832     vlc_mutex_unlock( &p_input->stream.stream_lock );
 833 }
 834
 835 /*****************************************************************************
 836  * input_ParsePS: read the PS header
 837  *****************************************************************************/
 838 es_descriptor_t * input_ParsePS( input_thread_t * p_input,
 839                                  data_packet_t * p_data )
 840 {
 841     u32                 i_code;
 842     es_descriptor_t *   p_es = NULL;
 843
 844     i_code = U32_AT( p_data->p_buffer );
 845     if( i_code > 0x1BC ) /* ES start code */
 846     {
 847         u16                 i_id;
 848         int                 i_dummy;
 849
 850         /* This is a PES packet. Find out if we want it or not. */
 851         i_id = GetID( p_data );
 852
 853         vlc_mutex_lock( &p_input->stream.stream_lock );
 854         if( p_input->stream.pp_programs[0]->b_is_ok )
 855         {
 856             /* Look only at the selected ES. */
 857             for( i_dummy = 0; i_dummy < p_input->stream.i_selected_es_number;
 858                  i_dummy++ )
 859             {
 860                 if( p_input->stream.pp_selected_es[i_dummy] != NULL
 861                     && p_input->stream.pp_selected_es[i_dummy]->i_id == i_id )
 862                 {
 863                     p_es = p_input->stream.pp_selected_es[i_dummy];
 864                     break;
 865                 }
 866             }
 867         }
 868         else
 869         {
 870             stream_ps_data_t * p_demux =
 871               (stream_ps_data_t *)p_input->stream.pp_programs[0]->p_demux_data;
 872
 873             /* Search all ES ; if not found -> AddES */
 874             p_es = input_FindES( p_input, i_id );
 875
 876             if( p_es == NULL && !p_demux->b_has_PSM )
 877             {
 878                 p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
 879                                     i_id, 0 );
 880                 if( p_es != NULL )
 881                 {
 882                     p_es->i_stream_id = p_data->p_buffer[3];
 883
 884                     /* Set stream type and auto-spawn. */
 885                     if( (i_id & 0xF0) == 0xE0 )
 886                     {
 887                         /* MPEG video */
 888                         p_es->i_type = MPEG2_VIDEO_ES;
 889 #ifdef AUTO_SPAWN
 890                         if( !p_input->stream.b_seekable )
 891                             input_SelectES( p_input, p_es );
 892 #endif
 893                     }
 894                     else if( (i_id & 0xE0) == 0xC0 )
 895                     {
 896                         /* MPEG audio */
 897                         p_es->i_type = MPEG2_AUDIO_ES;
 898 #ifdef AUTO_SPAWN
 899                         if( main_GetIntVariable( INPUT_DVD_AUDIO_VAR, 0 )
 900                                 == REQUESTED_MPEG
 901                           && main_GetIntVariable( INPUT_DVD_CHANNEL_VAR, 0 )
 902                                 == (p_es->i_id & 0x1F) )
 903                         {
 904                             if( !p_input->stream.b_seekable )
 905                                 input_SelectES( p_input, p_es );
 906                         }
 907 #endif
 908                     }
 909                     else if( (i_id & 0xF0FF) == 0x80BD )
 910                     {
 911                         /* AC3 audio (0x80->0x8F) */
 912                         p_es->i_type = AC3_AUDIO_ES;
 913 #ifdef AUTO_SPAWN
 914                         if( main_GetIntVariable( INPUT_DVD_AUDIO_VAR, 0 )
 915                                 == REQUESTED_AC3
 916                          && main_GetIntVariable( INPUT_DVD_CHANNEL_VAR, 0 )
 917                                 == ((p_es->i_id & 0xF00) >> 8) )
 918                         {
 919                             if( !p_input->stream.b_seekable )
 920                                 input_SelectES( p_input, p_es );
 921                         }
 922 #endif
 923                     }
 924                     else if( (i_id & 0xE0FF) == 0x20BD )
 925                     {
 926                         /* Subtitles video (0x20->0x3F) */
 927                         p_es->i_type = DVD_SPU_ES;
 928 #ifdef AUTO_SPAWN
 929                         if( main_GetIntVariable( INPUT_DVD_SUBTITLE_VAR, -1 )
 930                                 == ((p_es->i_id & 0x1F00) >> 8) )
 931                         {
 932                             if( !p_input->stream.b_seekable )
 933                                 input_SelectES( p_input, p_es );
 934                         }
 935 #endif
 936                     }
 937                     else if( (i_id & 0xF0FF) == 0xA0BD )
 938                     {
 939                         /* LPCM audio (0xA0->0xAF) */
 940                         p_es->i_type = LPCM_AUDIO_ES;
 941                         /* FIXME : write the decoder */
 942                     }
 943                     else
 944                     {
 945                         p_es->i_type = UNKNOWN_ES;
 946                     }
 947                 }
 948             }
 949         } /* stream.b_is_ok */
 950         vlc_mutex_unlock( &p_input->stream.stream_lock );
 951     } /* i_code > 0xBC */
 952
 953     return( p_es );
 954 }
 955
 956 /*****************************************************************************
 957  * input_DemuxPS: first step of demultiplexing: the PS header
 958  *****************************************************************************/
 959 void input_DemuxPS( input_thread_t * p_input, data_packet_t * p_data )
 960 {
 961     u32                 i_code;
 962     boolean_t           b_trash = 0;
 963     es_descriptor_t *   p_es = NULL;
 964
 965     i_code = U32_AT( p_data->p_buffer );
 966     if( i_code <= 0x1BC )
 967     {
 968         switch( i_code )
 969         {
 970         case 0x1BA: /* PACK_START_CODE */
 971             {
 972                 /* Convert the SCR in microseconds. */
 973                 mtime_t         scr_time;
 974
 975                 if( (p_data->p_buffer[4] & 0xC0) == 0x40 )
 976                 {
 977                     /* MPEG-2 */
 978                     scr_time =
 979                       (( ((mtime_t)(p_data->p_buffer[4] & 0x38) << 27) |
 980                          ((mtime_t)(U32_AT(p_data->p_buffer + 4) & 0x03FFF800)
 981                                         << 4) |
 982                          ((mtime_t)(U32_AT(p_data->p_buffer + 6) & 0x03FFF800)
 983                                         >> 11)
 984                       ) * 300) / 27;
 985                 }
 986                 else
 987                 {
 988                     /* MPEG-1 SCR is like PTS */
 989                     scr_time =
 990                       (( ((mtime_t)(p_data->p_buffer[4] & 0x0E) << 29) |
 991                          (((mtime_t)U16_AT(p_data->p_buffer + 5) << 14)
 992                            - (1 << 14)) |
 993                          ((mtime_t)U16_AT(p_data->p_buffer + 7) >> 1)
 994                       ) * 300) / 27;
 995                 }
 996                 /* Call the pace control. */
 997                 //intf_Msg("+%lld", scr_time);
 998                 CRDecode( p_input, p_input->stream.pp_programs[0],
 999                           scr_time );
1000                 b_trash = 1;
1001             }
1002             break;
1003
1004         case 0x1BB: /* SYSTEM_START_CODE */
1005             b_trash = 1;                              /* Nothing interesting */
1006             break;
1007
1008         case 0x1BC: /* PROGRAM_STREAM_MAP_CODE */
1009             DecodePSM( p_input, p_data );
1010             b_trash = 1;
1011             break;
1012
1013         case 0x1B9: /* PROGRAM_END_CODE */
1014             b_trash = 1;
1015             break;
1016
1017         default:
1018             /* This should not happen */
1019             b_trash = 1;
1020             intf_WarnMsg( 1, "Unwanted packet received with start code %x",
1021                           i_code );
1022         }
1023     }
1024     else
1025     {
1026         p_es = input_ParsePS( p_input, p_data );
1027
1028         if( p_es != NULL && p_es->p_decoder_fifo != NULL )
1029         {
1030 #ifdef STATS
1031             p_es->c_packets++;
1032 #endif
1033             input_GatherPES( p_input, p_data, p_es, 1, 0 );
1034         }
1035         else
1036         {
1037             b_trash = 1;
1038         }
1039     }
1040
1041     /* Trash the packet if it has no payload or if it isn't selected */
1042     if( b_trash )
1043     {
1044         p_input->p_plugin->pf_delete_packet( p_input, p_data );
1045 #ifdef STATS
1046         p_input->c_packets_trashed++;
1047 #endif
1048     }
1049 }
1050
1051
1052 /*
1053  * TS Demultiplexing
1054  */
1055
1056 /*****************************************************************************
1057  * input_DemuxTS: first step of demultiplexing: the TS header
1058  *****************************************************************************/
1059 void input_DemuxTS( input_thread_t * p_input, data_packet_t * p_data )
1060 {
1061     int                 i_pid, i_dummy;
1062     boolean_t           b_adaptation;         /* Adaptation field is present */
1063     boolean_t           b_payload;                 /* Packet carries payload */
1064     boolean_t           b_unit_start;  /* A PSI or a PES start in the packet */
1065     boolean_t           b_trash = 0;             /* Is the packet unuseful ? */
1066     boolean_t           b_lost = 0;             /* Was there a packet loss ? */
1067     es_descriptor_t *   p_es = NULL;
1068     es_ts_data_t *      p_es_demux = NULL;
1069     pgrm_ts_data_t *    p_pgrm_demux = NULL;
1070
1071 #define p (p_data->p_buffer)
1072
1073     //intf_DbgMsg("input debug: TS-demultiplexing packet %p, pid %d",
1074     //            p_ts_packet, U16_AT(&p[1]) & 0x1fff);
1075
1076     /* Extract flags values from TS common header. */
1077     i_pid = U16_AT(&p[1]) & 0x1fff;
1078     b_unit_start = (p[1] & 0x40);
1079     b_adaptation = (p[3] & 0x20);
1080     b_payload = (p[3] & 0x10);
1081
1082     /* Find out the elementary stream. */
1083     vlc_mutex_lock( &p_input->stream.stream_lock );
1084     p_es = input_FindES( p_input, i_pid );
1085     vlc_mutex_unlock( &p_input->stream.stream_lock );
1086
1087     if( p_es == NULL || p_es->p_decoder_fifo == NULL )
1088     {
1089         /* Not selected. Just read the adaptation field for a PCR. */
1090         b_trash = 1;
1091     }
1092
1093     if( (p_es->p_decoder_fifo != NULL) || (p_pgrm_demux->i_pcr_pid == i_pid) )
1094     {
1095 #ifdef STATS
1096         p_es->c_packets++;
1097 #endif
1098
1099         /* Extract adaptation field information if any */
1100         if( !b_adaptation )
1101         {
1102             /* We don't have any adaptation_field, so payload starts
1103              * immediately after the 4 byte TS header */
1104             p_data->p_payload_start += 4;
1105         }
1106         else
1107         {
1108             /* p[4] is adaptation_field_length minus one */
1109             p_data->p_payload_start += 5 + p[4];
1110
1111             /* The adaptation field can be limited to the
1112              * adaptation_field_length byte, so that there is nothing to do:
1113              * skip this possibility */
1114             if( p[4] )
1115             {
1116                 /* If the packet has both adaptation_field and payload,
1117                  * adaptation_field cannot be more than 182 bytes long; if
1118                  * there is only an adaptation_field, it must fill the next
1119                  * 183 bytes. */
1120                 if( b_payload ? (p[4] > 182) : (p[4] != 183) )
1121                 {
1122                     intf_WarnMsg( 2,
1123                         "invalid TS adaptation field (%p)",
1124                         p_data );
1125                     p_data->b_discard_payload = 1;
1126 #ifdef STATS
1127                     p_es->c_invalid_packets++;
1128 #endif
1129                 }
1130
1131                 /* Now we are sure that the byte containing flags is present:
1132                  * read it */
1133                 else
1134                 {
1135                     /* discontinuity_indicator */
1136                     if( p[5] & 0x80 )
1137                     {
1138                         intf_WarnMsg( 2,
1139                             "discontinuity_indicator"
1140                             " encountered by TS demux (position read: %d,"
1141                             " saved: %d)",
1142                             p[5] & 0x80, p_es_demux->i_continuity_counter );
1143
1144                         /* If the PID carries the PCR, there will be a system
1145                          * time-based discontinuity. We let the PCR decoder
1146                          * handle that. */
1147                         p_es->p_pgrm->b_discontinuity = 1;
1148
1149                         /* There also may be a continuity_counter
1150                          * discontinuity: resynchronise our counter with
1151                          * the one of the stream. */
1152                         p_es_demux->i_continuity_counter = (p[3] & 0x0f) - 1;
1153                     }
1154
1155                     /* If this is a PCR_PID, and this TS packet contains a
1156                      * PCR, we pass it along to the PCR decoder. */
1157                     if( (p_pgrm_demux->i_pcr_pid == i_pid) && (p[5] & 0x10) )
1158                     {
1159                         /* There should be a PCR field in the packet, check
1160                          * if the adaptation field is long enough to carry
1161                          * it. */
1162                         if( p[4] >= 7 )
1163                         {
1164                             /* Convert the PCR in microseconds.
1165                              * WARNING: do not remove the casts in the
1166                              * following calculation ! */
1167                             mtime_t     pcr_time;
1168                             pcr_time =
1169                                     ( (( (mtime_t)U32_AT((u32*)&p[6]) << 1 )
1170                                       | ( p[10] >> 7 )) * 300 ) / 27;
1171                             /* Call the pace control. */
1172                             CRDecode( p_input, p_es->p_pgrm, pcr_time );
1173                         }
1174                     } /* PCR ? */
1175                 } /* valid TS adaptation field ? */
1176             } /* length > 0 */
1177         } /* has adaptation field */
1178
1179         /* Check the continuity of the stream. */
1180         i_dummy = ((p[3] & 0x0f) - p_es_demux->i_continuity_counter) & 0x0f;
1181         if( i_dummy == 1 )
1182         {
1183             /* Everything is ok, just increase our counter */
1184             p_es_demux->i_continuity_counter++;
1185         }
1186         else
1187         {
1188             if( !b_payload && i_dummy == 0 )
1189             {
1190                 /* This is a packet without payload, this is allowed by the
1191                  * draft. As there is nothing interesting in this packet
1192                  * (except PCR that have already been handled), we can trash
1193                  * the packet. */
1194                 intf_WarnMsg( 1,
1195                               "Packet without payload received by TS demux" );
1196                 b_trash = 1;
1197             }
1198             else if( i_dummy <= 0 )
1199             {
1200                 /* FIXME: this can never happen, can it ? --Meuuh */
1201                 /* Duplicate packet: mark it as being to be trashed. */
1202                 intf_WarnMsg( 1, "Duplicate packet received by TS demux" );
1203                 b_trash = 1;
1204             }
1205             else if( p_es_demux->i_continuity_counter == 0xFF )
1206             {
1207                 /* This means that the packet is the first one we receive for
1208                  * this ES since the continuity counter ranges between 0 and
1209                  * 0x0F excepts when it has been initialized by the input:
1210                  * init the counter to the correct value. */
1211                 intf_DbgMsg( "First packet for PID %d received by TS demux",
1212                              p_es->i_id );
1213                 p_es_demux->i_continuity_counter = (p[3] & 0x0f);
1214             }
1215             else
1216             {
1217                 /* This can indicate that we missed a packet or that the
1218                  * continuity_counter wrapped and we received a dup packet:
1219                  * as we don't know, do as if we missed a packet to be sure
1220                  * to recover from this situation */
1221                 intf_WarnMsg( 2,
1222                            "Packet lost by TS demux: current %d, packet %d",
1223                            p_es_demux->i_continuity_counter & 0x0f,
1224                            p[3] & 0x0f );
1225                 b_lost = 1;
1226                 p_es_demux->i_continuity_counter = p[3] & 0x0f;
1227             } /* not continuous */
1228         } /* continuity */
1229     } /* if selected or PCR */
1230
1231     /* Trash the packet if it has no payload or if it isn't selected */
1232     if( b_trash )
1233     {
1234         p_input->p_plugin->pf_delete_packet( p_input, p_data );
1235 #ifdef STATS
1236         p_input->c_packets_trashed++;
1237 #endif
1238     }
1239     else
1240     {
1241         if( p_es_demux->b_psi )
1242         {
1243             /* The payload contains PSI tables */
1244 #if 0
1245             input_DemuxPSI( p_input, p_data, p_es,
1246                             b_unit_start, b_lost );
1247 #endif
1248         }
1249         else
1250         {
1251             /* The payload carries a PES stream */
1252             if( b_unit_start )
1253             input_GatherPES( p_input, p_data, p_es, b_unit_start, b_lost );
1254         }
1255     }
1256
1257 #undef p
1258 }