1 /*****************************************************************************
2 * udp.c: raw UDP & RTP input module
3 *****************************************************************************
4 * Copyright (C) 2001-2005 the VideoLAN team
7 * Authors: Christophe Massiot <massiot@via.ecp.fr>
8 * Tristan Leteurtre <tooney@via.ecp.fr>
9 * Laurent Aimar <fenrir@via.ecp.fr>
10 * Jean-Paul Saman <jpsaman #_at_# m2x dot nl>
12 * Reviewed: 23 October 2003, Jean-Paul Saman <jpsaman@wxs.nl>
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software
26 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
27 *****************************************************************************/
29 /*****************************************************************************
31 *****************************************************************************/
35 #include <vlc/input.h>
39 /*****************************************************************************
41 *****************************************************************************/
42 #define CACHING_TEXT N_("Caching value in ms")
43 #define CACHING_LONGTEXT N_( \
44 "Allows you to modify the default caching value for UDP streams. This " \
45 "value should be set in millisecond units." )
47 #define AUTO_MTU_TEXT N_("Autodetection of MTU")
48 #define AUTO_MTU_LONGTEXT N_( \
49 "Allows growing the MTU if truncated packets are found" )
51 #define RTP_LATE_TEXT N_("Reorder timeout in ms for late RTP packets")
52 #define RTP_LATE_LONGTEXT N_( \
53 "Allows you to modify the RTP packets reorder and late behaviour. " \
54 "If enabled (value>0) then out-of-order packets will be held for the " \
55 "specified timeout in ms. " \
56 "The default behaviour is not to reorder." )
58 static int Open ( vlc_object_t * );
59 static void Close( vlc_object_t * );
62 set_shortname( _("UDP/RTP" ) );
63 set_description( _("UDP/RTP input") );
64 set_category( CAT_INPUT );
65 set_subcategory( SUBCAT_INPUT_ACCESS );
67 add_integer( "udp-caching", DEFAULT_PTS_DELAY / 1000, NULL, CACHING_TEXT,
68 CACHING_LONGTEXT, VLC_TRUE );
69 add_bool( "udp-auto-mtu", 1, NULL,
70 AUTO_MTU_TEXT, AUTO_MTU_LONGTEXT, VLC_TRUE );
72 add_integer( "rtp-late", 0, NULL, RTP_LATE_TEXT, RTP_LATE_LONGTEXT, VLC_TRUE );
74 set_capability( "access2", 0 );
75 add_shortcut( "udp" );
76 add_shortcut( "udpstream" );
77 add_shortcut( "udp4" );
78 add_shortcut( "udp6" );
79 add_shortcut( "rtp" );
80 add_shortcut( "rtp4" );
81 add_shortcut( "rtp6" );
82 set_callbacks( Open, Close );
85 /*****************************************************************************
87 *****************************************************************************/
88 #define RTP_HEADER_LEN 12
89 #define RTP_SEQ_NUM_SIZE 65536
91 static block_t *BlockUDP( access_t * );
92 static block_t *BlockRTP( access_t * );
93 static block_t *BlockChoose( access_t * );
94 static int Control( access_t *, int, va_list );
101 vlc_bool_t b_auto_mtu;
104 uint16_t i_sequence_number;
105 vlc_bool_t b_first_seqno;
107 /* reorder rtp packets when out-of-bounds
108 * the packets hold queue is one level deep
110 uint32_t i_rtp_late; /* number of ms an RTP packet may be too late*/
111 uint32_t i_last_pcr; /* last known good PCR */
112 block_t *p_list; /* list of packets to rearrange */
113 block_t *p_end; /* last packet in p_list */
114 block_t *p_next; /* p_next ?? */
117 /*****************************************************************************
118 * Open: open the socket
119 *****************************************************************************/
120 static int Open( vlc_object_t *p_this )
122 access_t *p_access = (access_t*)p_this;
125 char *psz_name = strdup( p_access->psz_path );
126 char *psz_parser, *psz_server_addr, *psz_bind_addr = "";
127 int i_bind_port, i_server_port = 0;
129 /* First set ipv4/ipv6 */
130 var_Create( p_access, "ipv4", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
131 var_Create( p_access, "ipv6", VLC_VAR_BOOL | VLC_VAR_DOINHERIT );
133 if( *p_access->psz_access )
136 /* Find out which shortcut was used */
137 if( !strncmp( p_access->psz_access, "udp4", 6 ) ||
138 !strncmp( p_access->psz_access, "rtp4", 6 ))
140 val.b_bool = VLC_TRUE;
141 var_Set( p_access, "ipv4", val );
143 val.b_bool = VLC_FALSE;
144 var_Set( p_access, "ipv6", val );
146 else if( !strncmp( p_access->psz_access, "udp6", 6 ) ||
147 !strncmp( p_access->psz_access, "rtp6", 6 ) )
149 val.b_bool = VLC_TRUE;
150 var_Set( p_access, "ipv6", val );
152 val.b_bool = VLC_FALSE;
153 var_Set( p_access, "ipv4", val );
157 i_bind_port = var_CreateGetInteger( p_access, "server-port" );
159 /* Parse psz_name syntax :
160 * [serveraddr[:serverport]][@[bindaddr]:[bindport]] */
161 psz_parser = strchr( psz_name, '@' );
162 if( psz_parser != NULL )
164 /* Found bind address and/or bind port */
165 *psz_parser++ = '\0';
166 psz_bind_addr = psz_parser;
168 if( *psz_parser == '[' )
169 /* skips bracket'd IPv6 address */
170 psz_parser = strchr( psz_parser, ']' );
172 if( psz_parser != NULL )
174 psz_parser = strchr( psz_parser, ':' );
175 if( psz_parser != NULL )
177 *psz_parser++ = '\0';
178 i_bind_port = atoi( psz_parser );
183 psz_server_addr = psz_name;
184 if( *psz_server_addr == '[' )
185 /* skips bracket'd IPv6 address */
186 psz_parser = strchr( psz_name, ']' );
188 if( psz_parser != NULL )
190 psz_parser = strchr( psz_parser, ':' );
191 if( psz_parser != NULL )
193 *psz_parser++ = '\0';
194 i_server_port = atoi( psz_parser );
198 msg_Dbg( p_access, "opening server=%s:%d local=%s:%d",
199 psz_server_addr, i_server_port, psz_bind_addr, i_bind_port );
201 /* Set up p_access */
202 p_access->pf_read = NULL;
203 if( !strcasecmp( p_access->psz_access, "rtp" )
204 || !strcasecmp( p_access->psz_access, "rtp4" )
205 || !strcasecmp( p_access->psz_access, "rtp6" ) )
207 p_access->pf_block = BlockRTP;
211 p_access->pf_block = BlockChoose;
213 p_access->pf_control = Control;
214 p_access->pf_seek = NULL;
215 p_access->info.i_update = 0;
216 p_access->info.i_size = 0;
217 p_access->info.i_pos = 0;
218 p_access->info.b_eof = VLC_FALSE;
219 p_access->info.i_title = 0;
220 p_access->info.i_seekpoint = 0;
222 p_access->p_sys = p_sys = malloc( sizeof( access_sys_t ) );
223 p_sys->fd = net_OpenUDP( p_access, psz_bind_addr, i_bind_port,
224 psz_server_addr, i_server_port );
227 msg_Err( p_access, "cannot open socket" );
234 net_StopSend( p_sys->fd );
237 p_sys->i_mtu = var_CreateGetInteger( p_access, "mtu" );
238 if( p_sys->i_mtu <= 1 )
239 p_sys->i_mtu = 1500; /* Avoid problem */
241 p_sys->b_auto_mtu = var_CreateGetBool( p_access, "udp-auto-mtu" );;
243 /* Update default_pts to a suitable value for udp access */
244 var_Create( p_access, "udp-caching", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
246 /* Keep track of RTP sequence number */
247 p_sys->i_sequence_number = 0;
248 p_sys->b_first_seqno = VLC_TRUE;
250 /* RTP reordering out-of-bound packets */
251 p_sys->i_last_pcr = 0;
252 p_sys->i_rtp_late = var_CreateGetInteger( p_access, "rtp-late" );
253 p_sys->p_list = NULL;
255 p_sys->p_next = NULL;
260 /*****************************************************************************
261 * Close: free unused data structures
262 *****************************************************************************/
263 static void Close( vlc_object_t *p_this )
265 access_t *p_access = (access_t*)p_this;
266 access_sys_t *p_sys = p_access->p_sys;
268 block_ChainRelease( p_sys->p_list );
269 net_Close( p_sys->fd );
273 /*****************************************************************************
275 *****************************************************************************/
276 static int Control( access_t *p_access, int i_query, va_list args )
278 access_sys_t *p_sys = p_access->p_sys;
286 case ACCESS_CAN_SEEK:
287 case ACCESS_CAN_FASTSEEK:
288 case ACCESS_CAN_PAUSE:
289 case ACCESS_CAN_CONTROL_PACE:
290 pb_bool = (vlc_bool_t*)va_arg( args, vlc_bool_t* );
291 *pb_bool = VLC_FALSE;
295 pi_int = (int*)va_arg( args, int * );
296 *pi_int = p_sys->i_mtu;
299 case ACCESS_GET_PTS_DELAY:
300 pi_64 = (int64_t*)va_arg( args, int64_t * );
301 *pi_64 = var_GetInteger( p_access, "udp-caching" ) * 1000;
305 case ACCESS_SET_PAUSE_STATE:
306 case ACCESS_GET_TITLE_INFO:
307 case ACCESS_SET_TITLE:
308 case ACCESS_SET_SEEKPOINT:
309 case ACCESS_SET_PRIVATE_ID_STATE:
313 msg_Warn( p_access, "unimplemented query in control" );
320 /*****************************************************************************
322 *****************************************************************************/
323 static block_t *BlockUDP( access_t *p_access )
325 access_sys_t *p_sys = p_access->p_sys;
329 p_block = block_New( p_access, p_sys->i_mtu );
330 p_block->i_buffer = net_Read( p_access, p_sys->fd, NULL,
331 p_block->p_buffer, p_sys->i_mtu,
333 if( p_block->i_buffer <= 0 )
335 block_Release( p_block );
339 if( p_block->i_buffer >= p_sys->i_mtu && p_sys->b_auto_mtu &&
340 p_sys->i_mtu < 32767 )
342 /* Increase by 100% */
344 msg_Dbg( p_access, "increasing MTU to %d", p_sys->i_mtu );
351 * rtp_ChainInsert - insert a p_block in the chain and
352 * look at the sequence numbers.
354 static inline void rtp_ChainInsert( access_t *p_access, block_t **pp_list, block_t **pp_end, block_t *p_block )
356 block_t *p_tmp = NULL;
360 uint16_t i_expected = 0;
361 uint32_t i_pcr_new = 0;
363 if( *pp_list == NULL )
369 /* Appending packets at the end of the chain is the normal case */
370 i_pcr_new = ( (p_block->p_buffer[4] << 24) +
371 (p_block->p_buffer[5] << 16) +
372 (p_block->p_buffer[6] << 8) +
373 p_block->p_buffer[7] );
374 i_new = ( (p_block->p_buffer[2] << 8 ) + p_block->p_buffer[3] );
377 i_cur = ( (p->p_buffer[2] << 8 ) + p->p_buffer[3] );
378 i_expected = ((i_cur+1) % RTP_SEQ_NUM_SIZE);
379 if( (i_new - i_expected) >= 0 ) /* Append at the end? */
381 msg_Dbg( p_access, ">> append %p(%u)==%p(%u)\n", p_block, i_cur, p, i_new );
382 p->p_next = *pp_end = p_block;
385 /* Add to the front fo the chain? */
387 i_new = ( (p_block->p_buffer[2] << 8 ) + p_block->p_buffer[3] );
388 i_cur = ( (p->p_buffer[2] << 8 ) + p->p_buffer[3] );
389 if( (i_cur - i_new) > 0 )
391 msg_Dbg( p_access, ">> prepend %p(%u)==%p(%u)\n", p_block, i_cur, p, i_new );
396 /* The packet can't be added to the front or the end of the chain,
397 * thus walk the chain from the start.
401 i_cur = (p->p_buffer[2] << 8 ) + p->p_buffer[3];
402 i_expected = (i_cur+1) % RTP_SEQ_NUM_SIZE;
404 msg_Dbg( p_access, "i_cur: %u, i_new: %u", i_cur, i_new);
407 uint32_t i_pcr_cur = ( (p->p_buffer[4] << 24) +
408 (p->p_buffer[5] << 16) +
409 (p->p_buffer[6] << 8) +
411 /* This packet might be a duplicate, so check PCR's */
412 if( i_pcr_cur >= i_pcr_new )
414 /* packet way too late drop it. */
415 block_Release( p_block );
418 /* Add it to list later on
419 * else if( i_pcr_cur < i_pcr_new ) */
422 else if( (i_expected - i_new) >= 0 ) /* insert in chain */
425 msg_Dbg( p_access, ">> insert between %p(%u)==%p(%u)", p, i_cur, p_tmp, i_new );
427 p_block->p_next = p_tmp;
430 if( !p->p_next ) break;
436 * rtp_ChainSend - look which packets are ready for sending.
438 static inline block_t *rtp_ChainSend( access_t *p_access, block_t **pp_list, uint16_t i_seq )
440 access_sys_t *p_sys = (access_sys_t *) p_access->p_sys;
445 /* Parse RTP header */
447 int i_extension_bit = 0;
448 int i_extension_length = 0;
449 int i_CSRC_count = 0;
450 int i_payload_type = 0;
451 uint32_t i_pcr_prev = 0;
452 uint16_t i_seq_prev = 0;
454 block_t *p_prev = NULL;
455 block_t *p_send = *pp_list;
456 block_t *p = *pp_list;
460 i_cur = ( (p->p_buffer[2] << 8 ) + p->p_buffer[3] );
461 msg_Dbg( p_access, "rtp_ChainSend: i_cur %u, i_seq %u", i_cur, i_seq );
462 if( (i_cur - i_seq) == 0 )
464 i_seq++; /* sent all packets that are received in order */
466 /* Remember PCR and sequence number of packet
467 * for next iteration */
468 i_pcr_prev = ( (p->p_buffer[4] << 24) +
469 (p->p_buffer[5] << 16) +
470 (p->p_buffer[6] << 8) +
472 i_seq_prev = ( (p->p_buffer[2] << 8 ) +
475 /* Parse headerfields we need */
476 i_CSRC_count = p->p_buffer[0] & 0x0F;
477 i_payload_type = (p->p_buffer[1] & 0x7F);
478 i_extension_bit = ( p->p_buffer[0] & 0x10 ) >> 4;
479 if ( i_extension_bit == 1)
480 i_extension_length = ( (p->p_buffer[14] << 8 ) +
483 /* Skip header + CSRC extension field n*(32 bits) + extention */
484 i_skip = RTP_HEADER_LEN + 4*i_CSRC_count + i_extension_length;
485 if( i_payload_type == 14 ) i_skip += 4;
487 /* Return the packet without the RTP header. */
488 p->i_buffer -= i_skip;
489 p->p_buffer += i_skip;
491 else if( (i_cur - i_seq) > 0)
496 p_prev->p_next = NULL;
497 p_sys->i_last_pcr = i_pcr_prev;
498 p_sys->i_sequence_number = i_seq_prev;
501 /* FiXME: or should we return NULL here? */
505 if (!p->p_next) break;
508 /* We have walked through the complete chain and all packets are
509 * in sequence - so send the whole chain
511 i_payload_type = (p->p_buffer[1] & 0x7F);
512 i_CSRC_count = p->p_buffer[0] & 0x0F;
513 i_extension_bit = ( p->p_buffer[0] & 0x10 ) >> 4;
514 if( i_extension_bit == 1)
515 i_extension_length = ( (p->p_buffer[14] << 8 ) + p->p_buffer[15] );
517 /* Skip header + CSRC extension field n*(32 bits) + extention */
518 i_skip = RTP_HEADER_LEN + 4*i_CSRC_count + i_extension_length;
519 if( i_payload_type == 14 ) i_skip += 4;
521 /* Update the list pointers */
523 p_sys->p_next = NULL;
525 p_sys->i_sequence_number = ( (p->p_buffer[2] << 8 ) +
527 p_sys->i_last_pcr = ( (p->p_buffer[4] << 24) +
528 (p->p_buffer[5] << 16) +
529 (p->p_buffer[6] << 8) +
531 /* Return the packet without the RTP header. */
532 p->i_buffer -= i_skip;
533 p->p_buffer += i_skip;
539 /*****************************************************************************
540 * BlockParseRTP/BlockRTP:
541 *****************************************************************************/
542 static block_t *BlockParseRTP( access_t *p_access, block_t *p_block )
544 access_sys_t *p_sys = (access_sys_t *) p_access->p_sys;
549 uint16_t i_sequence_number = 0;
550 uint16_t i_sequence_expected = 0;
551 int i_extension_bit = 0;
552 int i_extension_length = 0;
555 if( p_block == NULL )
558 if( p_block->i_buffer < RTP_HEADER_LEN )
560 msg_Warn( p_access, "received a too short packet for RTP" );
561 block_Release( p_block );
564 /* Parse the header and make some verifications.
566 i_rtp_version = ( p_block->p_buffer[0] & 0xC0 ) >> 6;
567 i_CSRC_count = p_block->p_buffer[0] & 0x0F;
568 i_payload_type = p_block->p_buffer[1] & 0x7F;
569 i_sequence_number = (p_block->p_buffer[2] << 8) +
570 p_block->p_buffer[3];
571 i_pcr = ( (p_block->p_buffer[4] << 24) +
572 (p_block->p_buffer[5] << 16) +
573 (p_block->p_buffer[6] << 8) +
574 p_block->p_buffer[7] );
575 i_extension_bit = ( p_block->p_buffer[0] & 0x10 ) >> 4;
577 if( i_rtp_version != 2 )
578 msg_Dbg( p_access, "RTP version is %u, should be 2", i_rtp_version );
580 if( i_payload_type == 14 )
582 else if( i_payload_type != 33 && i_payload_type != 32 )
583 msg_Dbg( p_access, "unsupported RTP payload type (%u)", i_payload_type );
585 if( i_extension_bit == 1)
586 i_extension_length = 4 +
587 4 * ( (p_block->p_buffer[14] << 8) + p_block->p_buffer[15] );
589 /* Skip header + CSRC extension field n*(32 bits) + extention */
590 i_skip += RTP_HEADER_LEN + 4*i_CSRC_count + i_extension_length;
591 if( i_skip >= p_block->i_buffer )
593 msg_Warn( p_access, "received a too short packet for RTP" );
594 block_Release( p_block );
598 /* Detect RTP packet loss through tracking sequence numbers,
599 * and take RTP PCR into account.
602 if( p_sys->b_first_seqno )
604 p_sys->i_sequence_number = i_sequence_number-1;
605 p_sys->i_last_pcr = i_pcr;
606 p_sys->b_first_seqno = VLC_FALSE;
609 /* Emulate packet loss */
610 if ( (i_sequence_number % 4000) == 0)
612 msg_Warn( p_access, "Emulating packet drop" );
613 block_Release( p_block );
617 i_sequence_expected = ((p_sys->i_sequence_number + 1) % RTP_SEQ_NUM_SIZE);
618 if( (i_sequence_expected - i_sequence_number) != 0 )
620 /* Handle out of order packets */
621 if( p_sys->i_rtp_late > 0 )
623 if( (i_sequence_number - i_sequence_expected) > 0 )
626 "RTP packet out of order (too early) expected %u, current %u",
627 i_sequence_expected, i_sequence_number );
628 if( (i_pcr - p_sys->i_last_pcr) > (p_sys->i_rtp_late*90) )
630 block_t *p_start = p_sys->p_list;
631 uint16_t i_start = (p_start->p_buffer[2] << 8) +
632 p_start->p_buffer[3];
633 /* Gap too big, we have been holding this data for too long,
637 "Gap too big resyncing: delta %u, held for %d ms",
638 (i_pcr - p_sys->i_last_pcr), p_sys->i_rtp_late );
639 rtp_ChainInsert( p_access, &p_sys->p_list, &p_sys->p_end, p_block );
640 return rtp_ChainSend( p_access, &p_sys->p_list, i_start );
642 /* hold packets that arrive too early. */
643 rtp_ChainInsert( p_access, &p_sys->p_list, &p_sys->p_end, p_block );
644 return rtp_ChainSend( p_access, &p_sys->p_list, i_sequence_expected );
646 else if( /* ((i_sequence_expected - i_sequence_number ) > 0) && */
647 (i_pcr <= p_sys->i_last_pcr) )
650 "RTP packet out of order (duplicate or too late) expected %u, current %u .. trashing it",
651 i_sequence_expected, i_sequence_number );
652 block_Release( p_block );
653 p_sys->i_sequence_number = i_sequence_number;
654 p_sys->i_last_pcr = i_pcr;
661 block_t **p_send = &p_sys->p_list;
664 "RTP packet (unexpected condition) expected %u, current %u",
665 i_sequence_expected, i_sequence_number );
667 /* Append block to the end of chain and send whole chain */
668 block_ChainLastAppend( &p_send, p_block );
669 p_sys->p_list = p_sys->p_end = NULL;
670 p_sys->i_sequence_number = i_sequence_number;
671 p_sys->i_last_pcr = i_pcr;
673 /* Return the packet without the RTP header. */
677 p->i_buffer -= i_skip;
678 p->p_buffer += i_skip;
679 if( !p->p_next ) break;
684 /* This code should never be reached !! */
686 "Bug in algorithme: (unexpected condition) expected %u (pcr=%u), current %u (pcr=%u)",
687 i_sequence_expected, i_sequence_number, p_sys->i_last_pcr, i_pcr );
690 "RTP packet(s) lost, expected sequence number %d got %d",
691 i_sequence_expected, i_sequence_number );
693 /* Mark transport error in the first TS packet in the RTP stream. */
694 if( (i_payload_type == 33) && (p_block->p_buffer[0] == 0x47) )
695 p_block->p_buffer[1] |= 0x80;
697 else if( (p_sys->i_rtp_late > 0) && p_sys->p_list )
699 if( i_pcr <= p_sys->i_last_pcr )
702 "RTP packet out of order (duplicate) expected %u, current %u .. trashing it",
703 i_sequence_expected, i_sequence_number );
704 block_Release( p_block );
705 p_sys->i_sequence_number = i_sequence_number;
706 p_sys->i_last_pcr = i_pcr;
709 rtp_ChainInsert( p_access, &p_sys->p_list, &p_sys->p_end, p_block );
710 return rtp_ChainSend( p_access, &p_sys->p_list, i_sequence_expected );
713 /* This is the normal case when no packet reordering is effective */
714 p_sys->i_sequence_number = i_sequence_number;
715 p_sys->i_last_pcr = i_pcr;
717 /* Return the packet without the RTP header. */
718 p_block->i_buffer -= i_skip;
719 p_block->p_buffer += i_skip;
723 static block_t *BlockRTP( access_t *p_access )
725 block_t *p_block = BlockUDP( p_access );
727 if ( p_block != NULL )
728 return BlockParseRTP( p_access, p_block );
733 /*****************************************************************************
734 * BlockChoose: decide between RTP and UDP
735 *****************************************************************************/
736 static block_t *BlockChoose( access_t *p_access )
743 if( ( p_block = BlockUDP( p_access ) ) == NULL )
746 if( p_block->p_buffer[0] == 0x47 )
748 msg_Dbg( p_access, "detected TS over raw UDP" );
749 p_access->pf_block = BlockUDP;
753 if( p_block->i_buffer < RTP_HEADER_LEN )
756 /* Parse the header and make some verifications.
759 i_rtp_version = ( p_block->p_buffer[0] & 0xC0 ) >> 6;
760 i_CSRC_count = ( p_block->p_buffer[0] & 0x0F );
761 i_payload_type = ( p_block->p_buffer[1] & 0x7F );
763 if( i_rtp_version != 2 )
765 msg_Dbg( p_access, "no supported RTP header detected" );
766 p_access->pf_block = BlockUDP;
770 switch( i_payload_type )
773 msg_Dbg( p_access, "detected TS over RTP" );
774 p_access->psz_demux = strdup( "ts" );
778 msg_Dbg( p_access, "detected MPEG audio over RTP" );
779 p_access->psz_demux = strdup( "mpga" );
783 msg_Dbg( p_access, "detected MPEG video over RTP" );
784 p_access->psz_demux = strdup( "mpgv" );
788 msg_Dbg( p_access, "no RTP header detected" );
789 p_access->pf_block = BlockUDP;
793 p_access->pf_block = BlockRTP;
795 return BlockParseRTP( p_access, p_block );