modules/access/rtp/rtp.c

   1 /**
   2  * @file rtp.c
   3  * @brief Real-Time Protocol (RTP) demux module for VLC media player
   4  */
   5 /*****************************************************************************
   6  * Copyright (C) 2001-2005 VLC authors and VideoLAN
   7  * Copyright © 2007-2009 Rémi Denis-Courmont
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
  14  * This library 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 Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  22  ****************************************************************************/
  23
  24 #ifdef HAVE_CONFIG_H
  25 # include <config.h>
  26 #endif
  27 #include <stdarg.h>
  28 #include <assert.h>
  29
  30 #include <vlc_common.h>
  31 #include <vlc_demux.h>
  32 #include <vlc_network.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_dialog.h>
  35 #include <vlc_aout.h> /* aout_FormatPrepare() */
  36
  37 #include "rtp.h"
  38 #ifdef HAVE_SRTP
  39 # include <srtp.h>
  40 # include <gcrypt.h>
  41 # include <vlc_gcrypt.h>
  42 #endif
  43
  44 #define RTCP_PORT_TEXT N_("RTCP (local) port")
  45 #define RTCP_PORT_LONGTEXT N_( \
  46     "RTCP packets will be received on this transport protocol port. " \
  47     "If zero, multiplexed RTP/RTCP is used.")
  48
  49 #define SRTP_KEY_TEXT N_("SRTP key (hexadecimal)")
  50 #define SRTP_KEY_LONGTEXT N_( \
  51     "RTP packets will be authenticated and deciphered "\
  52     "with this Secure RTP master shared secret key. "\
  53     "This must be a 32-character-long hexadecimal string.")
  54
  55 #define SRTP_SALT_TEXT N_("SRTP salt (hexadecimal)")
  56 #define SRTP_SALT_LONGTEXT N_( \
  57     "Secure RTP requires a (non-secret) master salt value. " \
  58     "This must be a 28-character-long hexadecimal string.")
  59
  60 #define RTP_MAX_SRC_TEXT N_("Maximum RTP sources")
  61 #define RTP_MAX_SRC_LONGTEXT N_( \
  62     "How many distinct active RTP sources are allowed at a time." )
  63
  64 #define RTP_TIMEOUT_TEXT N_("RTP source timeout (sec)")
  65 #define RTP_TIMEOUT_LONGTEXT N_( \
  66     "How long to wait for any packet before a source is expired.")
  67
  68 #define RTP_MAX_DROPOUT_TEXT N_("Maximum RTP sequence number dropout")
  69 #define RTP_MAX_DROPOUT_LONGTEXT N_( \
  70     "RTP packets will be discarded if they are too much ahead (i.e. in the " \
  71     "future) by this many packets from the last received packet." )
  72
  73 #define RTP_MAX_MISORDER_TEXT N_("Maximum RTP sequence number misordering")
  74 #define RTP_MAX_MISORDER_LONGTEXT N_( \
  75     "RTP packets will be discarded if they are too far behind (i.e. in the " \
  76     "past) by this many packets from the last received packet." )
  77
  78 #define RTP_DYNAMIC_PT_TEXT N_("RTP payload format assumed for dynamic " \
  79                                "payloads")
  80 #define RTP_DYNAMIC_PT_LONGTEXT N_( \
  81     "This payload format will be assumed for dynamic payload types " \
  82     "(between 96 and 127) if it can't be determined otherwise with " \
  83     "out-of-band mappings (SDP)" )
  84
  85 static const char *const dynamic_pt_list[] = { "theora" };
  86 static const char *const dynamic_pt_list_text[] = { "Theora Encoded Video" };
  87
  88 static int  Open (vlc_object_t *);
  89 static void Close (vlc_object_t *);
  90
  91 /*
  92  * Module descriptor
  93  */
  94 vlc_module_begin ()
  95     set_shortname (N_("RTP"))
  96     set_description (N_("Real-Time Protocol (RTP) input"))
  97     set_category (CAT_INPUT)
  98     set_subcategory (SUBCAT_INPUT_DEMUX)
  99     set_capability ("access_demux", 0)
 100     set_callbacks (Open, Close)
 101
 102     add_integer ("rtcp-port", 0, RTCP_PORT_TEXT,
 103                  RTCP_PORT_LONGTEXT, false)
 104         change_integer_range (0, 65535)
 105         change_safe ()
 106 #ifdef HAVE_SRTP
 107     add_string ("srtp-key", "",
 108                 SRTP_KEY_TEXT, SRTP_KEY_LONGTEXT, false)
 109         change_safe ()
 110     add_string ("srtp-salt", "",
 111                 SRTP_SALT_TEXT, SRTP_SALT_LONGTEXT, false)
 112         change_safe ()
 113 #endif
 114     add_integer ("rtp-max-src", 1, RTP_MAX_SRC_TEXT,
 115                  RTP_MAX_SRC_LONGTEXT, true)
 116         change_integer_range (1, 255)
 117     add_integer ("rtp-timeout", 5, RTP_TIMEOUT_TEXT,
 118                  RTP_TIMEOUT_LONGTEXT, true)
 119     add_integer ("rtp-max-dropout", 3000, RTP_MAX_DROPOUT_TEXT,
 120                  RTP_MAX_DROPOUT_LONGTEXT, true)
 121         change_integer_range (0, 32767)
 122     add_integer ("rtp-max-misorder", 100, RTP_MAX_MISORDER_TEXT,
 123                  RTP_MAX_MISORDER_LONGTEXT, true)
 124         change_integer_range (0, 32767)
 125     add_string ("rtp-dynamic-pt", NULL, RTP_DYNAMIC_PT_TEXT,
 126                 RTP_DYNAMIC_PT_LONGTEXT, true)
 127         change_string_list (dynamic_pt_list, dynamic_pt_list_text)
 128
 129     /*add_shortcut ("sctp")*/
 130     add_shortcut ("dccp", "rtptcp", /* "tcp" is already taken :( */
 131                   "rtp", "udplite")
 132 vlc_module_end ()
 133
 134 /*
 135  * TODO: so much stuff
 136  * - send RTCP-RR and RTCP-BYE
 137  * - dynamic payload types (need SDP parser)
 138  * - multiple medias (need SDP parser, and RTCP-SR parser for lip-sync)
 139  * - support for stream_filter in case of chained demux (MPEG-TS)
 140  */
 141
 142 #ifndef IPPROTO_DCCP
 143 # define IPPROTO_DCCP 33 /* IANA */
 144 #endif
 145
 146 #ifndef IPPROTO_UDPLITE
 147 # define IPPROTO_UDPLITE 136 /* from IANA */
 148 #endif
 149
 150
 151 /*
 152  * Local prototypes
 153  */
 154 static int Control (demux_t *, int i_query, va_list args);
 155 static int extract_port (char **phost);
 156
 157 /**
 158  * Probes and initializes.
 159  */
 160 static int Open (vlc_object_t *obj)
 161 {
 162     demux_t *demux = (demux_t *)obj;
 163     int tp; /* transport protocol */
 164
 165     if (!strcasecmp(demux->psz_name, "dccp"))
 166         tp = IPPROTO_DCCP;
 167     else
 168     if (!strcasecmp(demux->psz_name, "rtptcp"))
 169         tp = IPPROTO_TCP;
 170     else
 171     if (!strcasecmp(demux->psz_name, "rtp"))
 172         tp = IPPROTO_UDP;
 173     else
 174     if (!strcasecmp(demux->psz_name, "udplite"))
 175         tp = IPPROTO_UDPLITE;
 176     else
 177         return VLC_EGENERIC;
 178
 179     char *tmp = strdup (demux->psz_location);
 180     if (tmp == NULL)
 181         return VLC_ENOMEM;
 182
 183     char *shost;
 184     char *dhost = strchr (tmp, '@');
 185     if (dhost != NULL)
 186     {
 187         *(dhost++) = '\0';
 188         shost = tmp;
 189     }
 190     else
 191     {
 192         dhost = tmp;
 193         shost = NULL;
 194     }
 195
 196     /* Parses the port numbers */
 197     int sport = 0, dport = 0;
 198     if (shost != NULL)
 199         sport = extract_port (&shost);
 200     if (dhost != NULL)
 201         dport = extract_port (&dhost);
 202     if (dport == 0)
 203         dport = 5004; /* avt-profile-1 port */
 204
 205     int rtcp_dport = var_CreateGetInteger (obj, "rtcp-port");
 206
 207     /* Try to connect */
 208     int fd = -1, rtcp_fd = -1;
 209
 210     switch (tp)
 211     {
 212         case IPPROTO_UDP:
 213         case IPPROTO_UDPLITE:
 214             fd = net_OpenDgram (obj, dhost, dport, shost, sport, tp);
 215             if (fd == -1)
 216                 break;
 217             if (rtcp_dport > 0) /* XXX: source port is unknown */
 218                 rtcp_fd = net_OpenDgram (obj, dhost, rtcp_dport, shost, 0, tp);
 219             break;
 220
 221          case IPPROTO_DCCP:
 222 #ifndef SOCK_DCCP /* provisional API (FIXME) */
 223 # ifdef __linux__
 224 #  define SOCK_DCCP 6
 225 # endif
 226 #endif
 227 #ifdef SOCK_DCCP
 228             var_Create (obj, "dccp-service", VLC_VAR_STRING);
 229             var_SetString (obj, "dccp-service", "RTPV"); /* FIXME: RTPA? */
 230             fd = net_Connect (obj, dhost, dport, SOCK_DCCP, tp);
 231 #else
 232             msg_Err (obj, "DCCP support not included");
 233 #endif
 234             break;
 235
 236         case IPPROTO_TCP:
 237             fd = net_Connect (obj, dhost, dport, SOCK_STREAM, tp);
 238             break;
 239     }
 240
 241     free (tmp);
 242     if (fd == -1)
 243         return VLC_EGENERIC;
 244     net_SetCSCov (fd, -1, 12);
 245
 246     /* Initializes demux */
 247     demux_sys_t *p_sys = malloc (sizeof (*p_sys));
 248     if (p_sys == NULL)
 249     {
 250         net_Close (fd);
 251         if (rtcp_fd != -1)
 252             net_Close (rtcp_fd);
 253         return VLC_EGENERIC;
 254     }
 255
 256     p_sys->chained_demux = NULL;
 257 #ifdef HAVE_SRTP
 258     p_sys->srtp         = NULL;
 259 #endif
 260     p_sys->fd           = fd;
 261     p_sys->rtcp_fd      = rtcp_fd;
 262     p_sys->max_src      = var_CreateGetInteger (obj, "rtp-max-src");
 263     p_sys->timeout      = var_CreateGetInteger (obj, "rtp-timeout")
 264                         * CLOCK_FREQ;
 265     p_sys->max_dropout  = var_CreateGetInteger (obj, "rtp-max-dropout");
 266     p_sys->max_misorder = var_CreateGetInteger (obj, "rtp-max-misorder");
 267     p_sys->thread_ready = false;
 268     p_sys->autodetect   = true;
 269
 270     demux->pf_demux   = NULL;
 271     demux->pf_control = Control;
 272     demux->p_sys      = p_sys;
 273
 274     p_sys->session = rtp_session_create (demux);
 275     if (p_sys->session == NULL)
 276         goto error;
 277
 278 #ifdef HAVE_SRTP
 279     char *key = var_CreateGetNonEmptyString (demux, "srtp-key");
 280     if (key)
 281     {
 282         vlc_gcrypt_init ();
 283         p_sys->srtp = srtp_create (SRTP_ENCR_AES_CM, SRTP_AUTH_HMAC_SHA1, 10,
 284                                    SRTP_PRF_AES_CM, SRTP_RCC_MODE1);
 285         if (p_sys->srtp == NULL)
 286         {
 287             free (key);
 288             goto error;
 289         }
 290
 291         char *salt = var_CreateGetNonEmptyString (demux, "srtp-salt");
 292         int val = srtp_setkeystring (p_sys->srtp, key, salt ? salt : "");
 293         free (salt);
 294         free (key);
 295         if (val)
 296         {
 297             msg_Err (obj, "bad SRTP key/salt combination (%s)",
 298                      vlc_strerror_c(val));
 299             goto error;
 300         }
 301     }
 302 #endif
 303
 304     if (vlc_clone (&p_sys->thread,
 305                    (tp != IPPROTO_TCP) ? rtp_dgram_thread : rtp_stream_thread,
 306                    demux, VLC_THREAD_PRIORITY_INPUT))
 307         goto error;
 308     p_sys->thread_ready = true;
 309     return VLC_SUCCESS;
 310
 311 error:
 312     Close (obj);
 313     return VLC_EGENERIC;
 314 }
 315
 316
 317 /**
 318  * Releases resources
 319  */
 320 static void Close (vlc_object_t *obj)
 321 {
 322     demux_t *demux = (demux_t *)obj;
 323     demux_sys_t *p_sys = demux->p_sys;
 324
 325     if (p_sys->thread_ready)
 326     {
 327         vlc_cancel (p_sys->thread);
 328         vlc_join (p_sys->thread, NULL);
 329     }
 330
 331 #ifdef HAVE_SRTP
 332     if (p_sys->srtp)
 333         srtp_destroy (p_sys->srtp);
 334 #endif
 335     if (p_sys->session)
 336         rtp_session_destroy (demux, p_sys->session);
 337     if (p_sys->rtcp_fd != -1)
 338         net_Close (p_sys->rtcp_fd);
 339     net_Close (p_sys->fd);
 340     free (p_sys);
 341 }
 342
 343
 344 /**
 345  * Extracts port number from "[host]:port" or "host:port" strings,
 346  * and remove brackets from the host name.
 347  * @param phost pointer to the string upon entry,
 348  * pointer to the hostname upon return.
 349  * @return port number, 0 if missing.
 350  */
 351 static int extract_port (char **phost)
 352 {
 353     char *host = *phost, *port;
 354
 355     if (host[0] == '[')
 356     {
 357         host = ++*phost; /* skip '[' */
 358         port = strchr (host, ']');
 359         if (port)
 360             *port++ = '\0'; /* skip ']' */
 361     }
 362     else
 363         port = strchr (host, ':');
 364
 365     if (port == NULL)
 366         return 0;
 367     *port++ = '\0'; /* skip ':' */
 368     return atoi (port);
 369 }
 370
 371
 372 /**
 373  * Control callback
 374  */
 375 static int Control (demux_t *demux, int query, va_list args)
 376 {
 377     demux_sys_t *sys = demux->p_sys;
 378
 379     switch (query)
 380     {
 381         case DEMUX_GET_PTS_DELAY:
 382         {
 383             int64_t *v = va_arg (args, int64_t *);
 384             *v = INT64_C(1000) * var_InheritInteger (demux, "network-caching");
 385             return VLC_SUCCESS;
 386         }
 387
 388         case DEMUX_CAN_PAUSE:
 389         case DEMUX_CAN_SEEK:
 390         case DEMUX_CAN_CONTROL_PACE:
 391         {
 392             bool *v = va_arg( args, bool * );
 393             *v = false;
 394             return VLC_SUCCESS;
 395         }
 396     }
 397
 398     if (sys->chained_demux != NULL)
 399         return vlc_demux_chained_ControlVa (sys->chained_demux, query, args);
 400
 401     switch (query)
 402     {
 403         case DEMUX_GET_POSITION:
 404         {
 405             float *v = va_arg (args, float *);
 406             *v = 0.;
 407             return VLC_SUCCESS;
 408         }
 409
 410         case DEMUX_GET_LENGTH:
 411         case DEMUX_GET_TIME:
 412         {
 413             int64_t *v = va_arg (args, int64_t *);
 414             *v = 0;
 415             return VLC_SUCCESS;
 416         }
 417     }
 418
 419     return VLC_EGENERIC;
 420 }
 421
 422
 423 /*
 424  * Generic packet handlers
 425  */
 426
 427 void *codec_init (demux_t *demux, es_format_t *fmt)
 428 {
 429     if (fmt->i_cat == AUDIO_ES)
 430         aout_FormatPrepare (&fmt->audio);
 431     return es_out_Add (demux->out, fmt);
 432 }
 433
 434 void codec_destroy (demux_t *demux, void *data)
 435 {
 436     if (data)
 437         es_out_Del (demux->out, (es_out_id_t *)data);
 438 }
 439
 440 /* Send a packet to decoder */
 441 void codec_decode (demux_t *demux, void *data, block_t *block)
 442 {
 443     if (data)
 444     {
 445         block->i_dts = VLC_TS_INVALID; /* RTP does not specify this */
 446         es_out_SetPCR(demux->out, block->i_pts);
 447         es_out_Send (demux->out, (es_out_id_t *)data, block);
 448     }
 449     else
 450         block_Release (block);
 451 }
 452
 453 static void *stream_init (demux_t *demux, const char *name)
 454 {
 455     demux_sys_t *p_sys = demux->p_sys;
 456
 457     if (p_sys->chained_demux != NULL)
 458         return NULL;
 459     p_sys->chained_demux = vlc_demux_chained_New(VLC_OBJECT(demux), name,
 460                                                  demux->out);
 461     return p_sys->chained_demux;
 462 }
 463
 464 static void stream_destroy (demux_t *demux, void *data)
 465 {
 466     demux_sys_t *p_sys = demux->p_sys;
 467
 468     if (data)
 469     {
 470         vlc_demux_chained_Delete(data);
 471         p_sys->chained_demux = NULL;
 472     }
 473 }
 474
 475 static void stream_header (demux_t *demux, void *data, block_t *block)
 476 {
 477     VLC_UNUSED(demux);
 478     VLC_UNUSED(data);
 479     if(block->p_buffer[1] & 0x80) /* TS M-bit == discontinuity (RFC 2250, 2.1) */
 480     {
 481         block->i_flags |= BLOCK_FLAG_DISCONTINUITY;
 482     }
 483 }
 484
 485 /* Send a packet to a chained demuxer */
 486 static void stream_decode (demux_t *demux, void *data, block_t *block)
 487 {
 488     if (data)
 489         vlc_demux_chained_Send(data, block);
 490     else
 491         block_Release (block);
 492     (void)demux;
 493 }
 494
 495 /*
 496  * Static payload types handler
 497  */
 498
 499 /* PT=0
 500  * PCMU: G.711 µ-law (RFC3551)
 501  */
 502 static void *pcmu_init (demux_t *demux)
 503 {
 504     es_format_t fmt;
 505
 506     es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_MULAW);
 507     fmt.audio.i_rate = 8000;
 508     fmt.audio.i_physical_channels = AOUT_CHAN_CENTER;
 509     return codec_init (demux, &fmt);
 510 }
 511
 512 /* PT=3
 513  * GSM
 514  */
 515 static void *gsm_init (demux_t *demux)
 516 {
 517     es_format_t fmt;
 518
 519     es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_GSM);
 520     fmt.audio.i_rate = 8000;
 521     fmt.audio.i_physical_channels = AOUT_CHAN_CENTER;
 522     return codec_init (demux, &fmt);
 523 }
 524
 525 /* PT=8
 526  * PCMA: G.711 A-law (RFC3551)
 527  */
 528 static void *pcma_init (demux_t *demux)
 529 {
 530     es_format_t fmt;
 531
 532     es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_ALAW);
 533     fmt.audio.i_rate = 8000;
 534     fmt.audio.i_physical_channels = AOUT_CHAN_CENTER;
 535     return codec_init (demux, &fmt);
 536 }
 537
 538 /* PT=10,11
 539  * L16: 16-bits (network byte order) PCM
 540  */
 541 static void *l16s_init (demux_t *demux)
 542 {
 543     es_format_t fmt;
 544
 545     es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_S16B);
 546     fmt.audio.i_rate = 44100;
 547     fmt.audio.i_physical_channels = AOUT_CHANS_STEREO;
 548     return codec_init (demux, &fmt);
 549 }
 550
 551 static void *l16m_init (demux_t *demux)
 552 {
 553     es_format_t fmt;
 554
 555     es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_S16B);
 556     fmt.audio.i_rate = 44100;
 557     fmt.audio.i_physical_channels = AOUT_CHAN_CENTER;
 558     return codec_init (demux, &fmt);
 559 }
 560
 561 /* PT=12
 562  * QCELP
 563  */
 564 static void *qcelp_init (demux_t *demux)
 565 {
 566     es_format_t fmt;
 567
 568     es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_QCELP);
 569     fmt.audio.i_rate = 8000;
 570     fmt.audio.i_physical_channels = AOUT_CHAN_CENTER;
 571     return codec_init (demux, &fmt);
 572 }
 573
 574 /* PT=14
 575  * MPA: MPEG Audio (RFC2250, §3.4)
 576  */
 577 static void *mpa_init (demux_t *demux)
 578 {
 579     es_format_t fmt;
 580
 581     es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_MPGA);
 582     fmt.audio.i_physical_channels = AOUT_CHANS_STEREO;
 583     fmt.b_packetized = false;
 584     return codec_init (demux, &fmt);
 585 }
 586
 587 static void mpa_decode (demux_t *demux, void *data, block_t *block)
 588 {
 589     if (block->i_buffer < 4)
 590     {
 591         block_Release (block);
 592         return;
 593     }
 594
 595     block->i_buffer -= 4; /* 32-bits RTP/MPA header */
 596     block->p_buffer += 4;
 597
 598     codec_decode (demux, data, block);
 599 }
 600
 601
 602 /* PT=32
 603  * MPV: MPEG Video (RFC2250, §3.5)
 604  */
 605 static void *mpv_init (demux_t *demux)
 606 {
 607     es_format_t fmt;
 608
 609     es_format_Init (&fmt, VIDEO_ES, VLC_CODEC_MPGV);
 610     fmt.b_packetized = false;
 611     return codec_init (demux, &fmt);
 612 }
 613
 614 static void mpv_decode (demux_t *demux, void *data, block_t *block)
 615 {
 616     if (block->i_buffer < 4)
 617     {
 618         block_Release (block);
 619         return;
 620     }
 621
 622     block->i_buffer -= 4; /* 32-bits RTP/MPV header */
 623     block->p_buffer += 4;
 624 #if 0
 625     if (block->p_buffer[-3] & 0x4)
 626     {
 627         /* MPEG2 Video extension header */
 628         /* TODO: shouldn't we skip this too ? */
 629     }
 630 #endif
 631     codec_decode (demux, data, block);
 632 }
 633
 634
 635 /* PT=33
 636  * MP2: MPEG TS (RFC2250, §2)
 637  */
 638 static void *ts_init (demux_t *demux)
 639 {
 640     char const* name = demux->psz_name;
 641
 642     if (*name == '\0' || !strcasecmp(name, "any"))
 643         name = NULL;
 644
 645     return stream_init (demux, name ? name : "ts");
 646 }
 647
 648
 649 /* Not using SDP, we need to guess the payload format used */
 650 /* see http://www.iana.org/assignments/rtp-parameters */
 651 void rtp_autodetect (demux_t *demux, rtp_session_t *session,
 652                      const block_t *block)
 653 {
 654     uint8_t ptype = rtp_ptype (block);
 655     rtp_pt_t pt = {
 656         .init = NULL,
 657         .destroy = codec_destroy,
 658         .header = NULL,
 659         .decode = codec_decode,
 660         .frequency = 0,
 661         .number = ptype,
 662     };
 663
 664     /* Remember to keep this in sync with modules/services_discovery/sap.c */
 665     switch (ptype)
 666     {
 667       case 0:
 668         msg_Dbg (demux, "detected G.711 mu-law");
 669         pt.init = pcmu_init;
 670         pt.frequency = 8000;
 671         break;
 672
 673       case 3:
 674         msg_Dbg (demux, "detected GSM");
 675         pt.init = gsm_init;
 676         pt.frequency = 8000;
 677         break;
 678
 679       case 8:
 680         msg_Dbg (demux, "detected G.711 A-law");
 681         pt.init = pcma_init;
 682         pt.frequency = 8000;
 683         break;
 684
 685       case 10:
 686         msg_Dbg (demux, "detected stereo PCM");
 687         pt.init = l16s_init;
 688         pt.frequency = 44100;
 689         break;
 690
 691       case 11:
 692         msg_Dbg (demux, "detected mono PCM");
 693         pt.init = l16m_init;
 694         pt.frequency = 44100;
 695         break;
 696
 697       case 12:
 698         msg_Dbg (demux, "detected QCELP");
 699         pt.init = qcelp_init;
 700         pt.frequency = 8000;
 701         break;
 702
 703       case 14:
 704         msg_Dbg (demux, "detected MPEG Audio");
 705         pt.init = mpa_init;
 706         pt.decode = mpa_decode;
 707         pt.frequency = 90000;
 708         break;
 709
 710       case 32:
 711         msg_Dbg (demux, "detected MPEG Video");
 712         pt.init = mpv_init;
 713         pt.decode = mpv_decode;
 714         pt.frequency = 90000;
 715         break;
 716
 717       case 33:
 718         msg_Dbg (demux, "detected MPEG2 TS");
 719         pt.init = ts_init;
 720         pt.destroy = stream_destroy;
 721         pt.header = stream_header;
 722         pt.decode = stream_decode;
 723         pt.frequency = 90000;
 724         break;
 725
 726       default:
 727         if (ptype >= 96)
 728         {
 729             char *dynamic = var_InheritString(demux, "rtp-dynamic-pt");
 730             if (dynamic == NULL)
 731                 ;
 732             else if (!strcmp(dynamic, "theora"))
 733             {
 734                 msg_Dbg (demux, "assuming Theora Encoded Video");
 735                 pt.init = theora_init;
 736                 pt.destroy = xiph_destroy;
 737                 pt.decode = xiph_decode;
 738                 pt.frequency = 90000;
 739
 740                 free (dynamic);
 741                 break;
 742             }
 743             else
 744                 msg_Err (demux, "unknown dynamic payload format `%s' "
 745                                 "specified", dynamic);
 746             free (dynamic);
 747         }
 748
 749         msg_Err (demux, "unspecified payload format (type %"PRIu8")", ptype);
 750         msg_Info (demux, "A valid SDP is needed to parse this RTP stream.");
 751         vlc_dialog_display_error (demux, N_("SDP required"),
 752              N_("A description in SDP format is required to receive the RTP "
 753                 "stream. Note that rtp:// URIs cannot work with dynamic "
 754                 "RTP payload format (%"PRIu8")."), ptype);
 755         return;
 756     }
 757     rtp_add_type (demux, session, &pt);
 758 }
 759
 760 /*
 761  * Dynamic payload type handlers
 762  * Hmm, none implemented yet apart from Xiph ones.
 763  */