modules/mux/mpeg/pes.c

   1 /*****************************************************************************
   2  * pes.c: PES packetizer used by the MPEG multiplexers
   3  *****************************************************************************
   4  * Copyright (C) 2001, 2002 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   8  *          Eric Petit <titer@videolan.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with this program; if not, write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <vlc_common.h>
  34 #include <vlc_sout.h>
  35 #include <vlc_block.h>
  36 #include <assert.h>
  37
  38 #include "pes.h"
  39 #include "bits.h"
  40
  41 /** PESHeader, write a pes header
  42  * \param i_es_size length of payload data. (Must be < PES_PAYLOAD_SIZE_MAX
  43  *                  unless the conditions for unbounded PES packets are met)
  44  * \param i_stream_id stream id as follows:
  45  *                     - 0x00   - 0xff   : normal stream_id as per Table 2-18
  46  *                     - 0xfd00 - 0xfd7f : stream_id_extension = low 7 bits
  47  *                                         (stream_id = PES_EXTENDED_STREAM_ID)
  48  *                     - 0xbd00 - 0xbdff : private_id = low 8 bits
  49  *                                         (stream_id = PES_PRIVATE_STREAM)
  50  * \param i_header_size length of padding data to insert into PES packet
  51  *                      header in bytes.
  52  */
  53 static inline int PESHeader( uint8_t *p_hdr, mtime_t i_pts, mtime_t i_dts,
  54                              int i_es_size, const es_format_t *p_fmt,
  55                              int i_stream_id, bool b_mpeg2,
  56                              bool b_data_alignment, int i_header_size )
  57 {
  58     bits_buffer_t bits;
  59     int     i_extra = 0;
  60     int i_private_id = -1;
  61     int i_stream_id_extension = 0;
  62
  63     /* HACK for private stream 1 in ps */
  64     if( ( i_stream_id >> 8 ) == PES_PRIVATE_STREAM_1 )
  65     {
  66         i_private_id = i_stream_id & 0xff;
  67         i_stream_id = PES_PRIVATE_STREAM_1;
  68         /* For PES_PRIVATE_STREAM_1 there is an extra header after the
  69            pes header */
  70         /* i_private_id != -1 because TS use 0xbd without private_id */
  71         i_extra = 1;
  72         if( ( i_private_id & 0xf0 ) == 0x80 )
  73             i_extra += 3;
  74     }
  75     else if( ( i_stream_id >> 8 ) == PES_EXTENDED_STREAM_ID )
  76     {
  77         /* Enable support for extended_stream_id as defined in
  78          * ISO/IEC 13818-1:2000/Amd.2:2003 */
  79         /* NB, i_extended_stream_id is limited to 7 bits */
  80         i_stream_id_extension = i_stream_id & 0x7f;
  81         i_stream_id = PES_EXTENDED_STREAM_ID;
  82     }
  83
  84     bits_initwrite( &bits, 50, p_hdr );
  85
  86     /* add start code */
  87     bits_write( &bits, 24, 0x01 );
  88     bits_write( &bits, 8, i_stream_id );
  89     switch( i_stream_id )
  90     {
  91         case PES_PROGRAM_STREAM_MAP:
  92         case PES_PADDING:
  93         case PES_PRIVATE_STREAM_2:
  94         case PES_ECM:
  95         case PES_EMM:
  96         case PES_PROGRAM_STREAM_DIRECTORY:
  97         case PES_DSMCC_STREAM:
  98         case PES_ITU_T_H222_1_TYPE_E_STREAM:
  99             /* add pes data size  */
 100             bits_write( &bits, 16, i_es_size );
 101             bits_align( &bits );
 102             return( bits.i_data );
 103
 104         default:
 105             /* arg, a little more difficult */
 106             if( b_mpeg2 )
 107             {
 108                 int i_pts_dts;
 109                 bool b_pes_extension_flag = false;
 110
 111                 if( i_pts > 0 && i_dts > 0 &&
 112                     ( i_pts != i_dts || ( p_fmt->i_cat == VIDEO_ES &&
 113                       p_fmt->i_codec != VLC_CODEC_MPGV &&
 114                       p_fmt->i_codec != VLC_CODEC_MP2V &&
 115                       p_fmt->i_codec != VLC_CODEC_MP1V
 116                       ) ) )
 117                 {
 118                     i_pts_dts = 0x03;
 119                     if ( !i_header_size ) i_header_size = 0xa;
 120                 }
 121                 else if( i_pts > 0 )
 122                 {
 123                     i_pts_dts = 0x02;
 124                     if ( !i_header_size ) i_header_size = 0x5;
 125                 }
 126                 else
 127                 {
 128                     i_pts_dts = 0x00;
 129                     if ( !i_header_size ) i_header_size = 0x0;
 130                 }
 131
 132                 if( i_stream_id == PES_EXTENDED_STREAM_ID )
 133                 {
 134                     b_pes_extension_flag = true;
 135                     i_header_size += 1 + 1;
 136                 }
 137
 138                 if( b_pes_extension_flag )
 139                 {
 140                     i_header_size += 1;
 141                 }
 142
 143                 /* Unbounded streams are only allowed in TS (not PS) and only
 144                  * for some ES, eg. MPEG* Video ES or Dirac ES. */
 145                 if( i_es_size > PES_PAYLOAD_SIZE_MAX )
 146                     bits_write( &bits, 16, 0 ); // size unbounded
 147                 else
 148                     bits_write( &bits, 16, i_es_size + i_extra + 3
 149                                  + i_header_size ); // size
 150                 bits_write( &bits, 2, 0x02 ); // mpeg2 id
 151                 bits_write( &bits, 2, 0x00 ); // pes scrambling control
 152                 bits_write( &bits, 1, 0x00 ); // pes priority
 153                 bits_write( &bits, 1, b_data_alignment ); // data alignement indicator
 154                 bits_write( &bits, 1, 0x00 ); // copyright
 155                 bits_write( &bits, 1, 0x00 ); // original or copy
 156
 157                 bits_write( &bits, 2, i_pts_dts ); // pts_dts flags
 158                 bits_write( &bits, 1, 0x00 ); // escr flags
 159                 bits_write( &bits, 1, 0x00 ); // es rate flag
 160                 bits_write( &bits, 1, 0x00 ); // dsm trick mode flag
 161                 bits_write( &bits, 1, 0x00 ); // additional copy info flag
 162                 bits_write( &bits, 1, 0x00 ); // pes crc flag
 163                 bits_write( &bits, 1, b_pes_extension_flag );
 164                 bits_write( &bits, 8, i_header_size );
 165
 166                 /* write pts */
 167                 if( i_pts_dts & 0x02 )
 168                 {
 169                     bits_write( &bits, 4, i_pts_dts ); // '0010' or '0011'
 170                     bits_write( &bits, 3, i_pts >> 30 );
 171                     bits_write( &bits, 1, 0x01 ); // marker
 172                     bits_write( &bits, 15, i_pts >> 15 );
 173                     bits_write( &bits, 1, 0x01 ); // marker
 174                     bits_write( &bits, 15, i_pts );
 175                     bits_write( &bits, 1, 0x01 ); // marker
 176                     i_header_size -= 0x5;
 177                 }
 178                 /* write i_dts */
 179                 if( i_pts_dts & 0x01 )
 180                 {
 181                     bits_write( &bits, 4, 0x01 ); // '0001'
 182                     bits_write( &bits, 3, i_dts >> 30 );
 183                     bits_write( &bits, 1, 0x01 ); // marker
 184                     bits_write( &bits, 15, i_dts >> 15 );
 185                     bits_write( &bits, 1, 0x01 ); // marker
 186                     bits_write( &bits, 15, i_dts );
 187                     bits_write( &bits, 1, 0x01 ); // marker
 188                     i_header_size -= 0x5;
 189                 }
 190                 if( b_pes_extension_flag )
 191                 {
 192                     bits_write( &bits, 1, 0x00 ); // PES_private_data_flag
 193                     bits_write( &bits, 1, 0x00 ); // pack_header_field_flag
 194                     bits_write( &bits, 1, 0x00 ); // program_packet_sequence_counter_flag
 195                     bits_write( &bits, 1, 0x00 ); // P-STD_buffer_flag
 196                     bits_write( &bits, 3, 0x07 ); // reserved
 197                     bits_write( &bits, 1, 0x01 ); // PES_extension_flag_2
 198                     /* skipping unsupported parts: */
 199                     /*   PES_private_data */
 200                     /*   pack_header */
 201                     /*   program_packet_sequence_counter */
 202                     /*   P-STD_buffer_flag */
 203                     if( i_stream_id == PES_EXTENDED_STREAM_ID )
 204                     {
 205                         /* PES_extension_2 */
 206                         bits_write( &bits, 1, 0x01 ); // marker
 207                         bits_write( &bits, 7, 0x01 ); // PES_extension_field_length
 208                         bits_write( &bits, 1, 0x01 ); // stream_id_extension_flag
 209                         bits_write( &bits, 7, i_stream_id_extension );
 210                         i_header_size -= 0x2;
 211                     }
 212                     i_header_size -= 0x1;
 213                 }
 214                 while ( i_header_size )
 215                 {
 216                     bits_write( &bits, 8, 0xff );
 217                     i_header_size--;
 218                 }
 219             }
 220             else /* MPEG1 */
 221             {
 222                 int i_pts_dts;
 223
 224                 if( i_pts > 0 && i_dts > 0 &&
 225                     ( i_pts != i_dts || p_fmt->i_cat == VIDEO_ES ) )
 226                 {
 227                     bits_write( &bits, 16, i_es_size + i_extra + 10 /* + stuffing */ );
 228                     i_pts_dts = 0x03;
 229                 }
 230                 else if( i_pts > 0 )
 231                 {
 232                     bits_write( &bits, 16, i_es_size + i_extra + 5 /* + stuffing */ );
 233                     i_pts_dts = 0x02;
 234                 }
 235                 else
 236                 {
 237                     bits_write( &bits, 16, i_es_size + i_extra + 1 /* + stuffing */);
 238                     i_pts_dts = 0x00;
 239                 }
 240
 241                 /* FIXME: Now should be stuffing */
 242
 243                 /* No STD_buffer_scale and STD_buffer_size */
 244
 245                 /* write pts */
 246                 if( i_pts_dts & 0x02 )
 247                 {
 248                     bits_write( &bits, 4, i_pts_dts ); // '0010' or '0011'
 249                     bits_write( &bits, 3, i_pts >> 30 );
 250                     bits_write( &bits, 1, 0x01 ); // marker
 251                     bits_write( &bits, 15, i_pts >> 15 );
 252                     bits_write( &bits, 1, 0x01 ); // marker
 253                     bits_write( &bits, 15, i_pts );
 254                     bits_write( &bits, 1, 0x01 ); // marker
 255                 }
 256                 /* write i_dts */
 257                 if( i_pts_dts & 0x01 )
 258                 {
 259                     bits_write( &bits, 4, 0x01 ); // '0001'
 260                     bits_write( &bits, 3, i_dts >> 30 );
 261                     bits_write( &bits, 1, 0x01 ); // marker
 262                     bits_write( &bits, 15, i_dts >> 15 );
 263                     bits_write( &bits, 1, 0x01 ); // marker
 264                     bits_write( &bits, 15, i_dts );
 265                     bits_write( &bits, 1, 0x01 ); // marker
 266                 }
 267                 if( !i_pts_dts )
 268                 {
 269                     bits_write( &bits, 8, 0x0F );
 270                 }
 271
 272             }
 273
 274             /* now should be stuffing */
 275             /* and then pes data */
 276
 277             bits_align( &bits );
 278             if( i_stream_id == PES_PRIVATE_STREAM_1 && i_private_id != -1 )
 279             {
 280                 bits_write( &bits, 8, i_private_id );
 281                 if( ( i_private_id&0xf0 ) == 0x80 )
 282                 {
 283                     bits_write( &bits, 24, 0 ); // ac3
 284                 }
 285             }
 286             bits_align( &bits );
 287             return( bits.i_data );
 288     }
 289 }
 290
 291 /** EStoPES, encapsulate an elementary stream block into PES packet(s)
 292  * each with a maximal payload size of @i_max_pes_size@.
 293  *
 294  * In some circumstances, unbounded PES packets are allowed:
 295  *  - Transport streams only (NOT programme streams)
 296  *  - Only some types of elementary streams (eg MPEG2 video)
 297  * It is the responsibility of the caller to enforce these constraints.
 298  *
 299  * EStoPES will only produce an unbounded PES packet if:
 300  *  - ES is VIDEO_ES
 301  *  - i_max_pes_size > PES_PAYLOAD_SIZE_MAX
 302  *  - length of p_es > PES_PAYLOAD_SIZE_MAX
 303  * If the last condition is not met, a single PES packet is produced
 304  * which is not unbounded in length.
 305  *
 306  * \param i_stream_id stream id as follows:
 307  *                     - 0x00   - 0xff   : normal stream_id as per Table 2-18
 308  *                     - 0xfd00 - 0xfd7f : stream_id_extension = low 7 bits
 309  *                                         (stream_id = PES_EXTENDED_STREAM_ID)
 310  *                     - 0xbd00 - 0xbdff : private_id = low 8 bits
 311  *                                         (stream_id = PES_PRIVATE_STREAM)
 312  * \param i_header_size length of padding data to insert into PES packet
 313  *                      header in bytes.
 314  * \param i_max_pes_size maximum length of each pes packet payload.
 315  *                       if zero, uses default maximum.
 316  *                       To allow unbounded PES packets in transport stream
 317  *                       VIDEO_ES, set to INT_MAX.
 318  */
 319 void EStoPES ( block_t **pp_pes,
 320                    const es_format_t *p_fmt, int i_stream_id,
 321                    int b_mpeg2, int b_data_alignment, int i_header_size,
 322                    int i_max_pes_size, mtime_t ts_offset )
 323 {
 324     block_t *p_es = *pp_pes;
 325     block_t *p_pes = NULL;
 326
 327     uint8_t *p_data;
 328     int     i_size;
 329
 330     uint8_t header[50];     // PES header + extra < 50 (more like 17)
 331     int     i_pes_payload;
 332     int     i_pes_header;
 333
 334     int     i_pes_count = 1;
 335
 336     assert( i_max_pes_size >= 0 );
 337     assert( i_header_size >= 0 );
 338
 339     /* NB, Only video ES may have unbounded length */
 340     if( !i_max_pes_size ||
 341         ( p_fmt->i_cat != VIDEO_ES && i_max_pes_size > PES_PAYLOAD_SIZE_MAX ) )
 342     {
 343         i_max_pes_size = PES_PAYLOAD_SIZE_MAX;
 344     }
 345
 346     if( ( p_fmt->i_codec == VLC_CODEC_MP4V ||
 347           p_fmt->i_codec == VLC_CODEC_H264 ||
 348           p_fmt->i_codec == VLC_CODEC_HEVC) &&
 349         p_es->i_flags & BLOCK_FLAG_TYPE_I )
 350     {
 351         /* For MPEG4 video, add VOL before I-frames,
 352            for H264 add SPS/PPS before keyframes*/
 353         p_es = block_Realloc( p_es, p_fmt->i_extra, p_es->i_buffer );
 354
 355         memcpy( p_es->p_buffer, p_fmt->p_extra, p_fmt->i_extra );
 356     }
 357
 358     if( p_fmt->i_codec == VLC_CODEC_H264 )
 359     {
 360         unsigned offset=2;
 361         while(offset < p_es->i_buffer )
 362         {
 363             if( p_es->p_buffer[offset-2] == 0 &&
 364                 p_es->p_buffer[offset-1] == 0 &&
 365                 p_es->p_buffer[offset] == 1 )
 366                 break;
 367             offset++;
 368         }
 369         offset++;
 370         if( offset <= p_es->i_buffer-4 &&
 371             ((p_es->p_buffer[offset] & 0x1f) != 9) ) /* Not AUD */
 372         {
 373             /* Make similar AUD as libavformat does */
 374             p_es = block_Realloc( p_es, 6, p_es->i_buffer );
 375             p_es->p_buffer[0] = 0x00;
 376             p_es->p_buffer[1] = 0x00;
 377             p_es->p_buffer[2] = 0x00;
 378             p_es->p_buffer[3] = 0x01;
 379             p_es->p_buffer[4] = 0x09; /* FIXME: primary_pic_type from SPS/PPS */
 380             p_es->p_buffer[5] = 0xf0;
 381         }
 382
 383     }
 384
 385     mtime_t i_dts = 0;
 386     mtime_t i_pts = 0;
 387     if (p_es->i_pts > VLC_TS_INVALID)
 388         i_pts = (p_es->i_pts - ts_offset) * 9 / 100;
 389     if (p_es->i_dts > VLC_TS_INVALID)
 390         i_dts = (p_es->i_dts - ts_offset) * 9 / 100;
 391
 392     i_size = p_es->i_buffer;
 393     p_data = p_es->p_buffer;
 394
 395     do
 396     {
 397         i_pes_payload = __MIN( i_size, i_max_pes_size );
 398         i_pes_header  = PESHeader( header, i_pts, i_dts, i_pes_payload,
 399                                    p_fmt, i_stream_id, b_mpeg2,
 400                                    b_data_alignment, i_header_size );
 401         i_dts = 0; // only first PES has a dts/pts
 402         i_pts = 0;
 403
 404         if( p_es )
 405         {
 406             p_es = block_Realloc( p_es, i_pes_header, p_es->i_buffer );
 407             p_data = p_es->p_buffer+i_pes_header;
 408             /* reuse p_es for first frame */
 409             *pp_pes = p_pes = p_es;
 410             /* don't touch i_dts, i_pts, i_length as are already set :) */
 411             p_es = NULL;
 412         }
 413         else
 414         {
 415             p_pes->p_next = block_Alloc( i_pes_header + i_pes_payload );
 416             p_pes = p_pes->p_next;
 417
 418             p_pes->i_dts    = 0;
 419             p_pes->i_pts    = 0;
 420             p_pes->i_length = 0;
 421             if( i_pes_payload > 0 )
 422             {
 423                 memcpy( p_pes->p_buffer + i_pes_header, p_data,
 424                             i_pes_payload );
 425             }
 426             i_pes_count++;
 427         }
 428
 429         /* copy header */
 430         memcpy( p_pes->p_buffer, header, i_pes_header );
 431
 432         i_size -= i_pes_payload;
 433         p_data += i_pes_payload;
 434         p_pes->i_buffer =  i_pes_header + i_pes_payload;
 435
 436     } while( i_size > 0 );
 437
 438     /* Now redate all pes */
 439     p_pes = *pp_pes;
 440     i_dts    = p_pes->i_dts;
 441     mtime_t i_length = p_pes->i_length / i_pes_count;
 442     while( p_pes )
 443     {
 444         p_pes->i_dts = i_dts;
 445         p_pes->i_length = i_length;
 446
 447         i_dts += i_length;
 448         p_pes = p_pes->p_next;
 449     }
 450 }