/*****************************************************************************
* udp.c: raw UDP & RTP input module
*****************************************************************************
- * Copyright (C) 2001-2004 the VideoLAN team
+ * Copyright (C) 2001-2005 the VideoLAN team
* $Id$
*
* Authors: Christophe Massiot <massiot@via.ecp.fr>
#define AUTO_MTU_LONGTEXT N_( \
"Allows growing the MTU if truncated packets are found" )
+#define RTP_LATE_TEXT N_("RTP reordering timeout in ms")
+#define RTP_LATE_LONGTEXT N_( \
+ "Allows you to modify the RTP reordering behaviour. " \
+ "RTP input will wait for late packets upto " \
+ "the specified timeout in milisecond units." )
+
static int Open ( vlc_object_t * );
static void Close( vlc_object_t * );
add_integer( "udp-caching", DEFAULT_PTS_DELAY / 1000, NULL, CACHING_TEXT,
CACHING_LONGTEXT, VLC_TRUE );
+ add_integer( "rtp-late", 100, NULL, RTP_LATE_TEXT, RTP_LATE_LONGTEXT, VLC_TRUE );
+
add_bool( "udp-auto-mtu", 1, NULL,
AUTO_MTU_TEXT, AUTO_MTU_LONGTEXT, VLC_TRUE );
int i_mtu;
vlc_bool_t b_auto_mtu;
- /* rtp only */
- int i_sequence_number;
+ /* reorder rtp packets when out-of-sequence */
+ int64_t i_rtp_late;
+ uint16_t i_last_seqno;
+ block_t *p_list;
+ block_t *p_end;
};
/*****************************************************************************
p_access->info.i_size = 0;
p_access->info.i_pos = 0;
p_access->info.b_eof = VLC_FALSE;
+ p_access->info.b_prebuffered = VLC_FALSE;
p_access->info.i_title = 0;
p_access->info.i_seekpoint = 0;
/* Update default_pts to a suitable value for udp access */
var_Create( p_access, "udp-caching", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
- /* Keep track of RTP sequence number */
- p_sys->i_sequence_number = -1;
+ /* RTP reordering for out-of-sequence packets */
+ p_sys->i_rtp_late = var_CreateGetInteger( p_access, "rtp-late" ) * 1000;
+ p_sys->i_last_seqno = 0;
+ p_sys->p_list = NULL;
+ p_sys->p_end = NULL;
return VLC_SUCCESS;
}
access_t *p_access = (access_t*)p_this;
access_sys_t *p_sys = p_access->p_sys;
+ block_ChainRelease( p_sys->p_list );
net_Close( p_sys->fd );
free( p_sys );
}
return NULL;
}
- if( p_block->i_buffer >= p_sys->i_mtu && p_sys->b_auto_mtu &&
+ if( (p_block->i_buffer >= p_sys->i_mtu) && p_sys->b_auto_mtu &&
p_sys->i_mtu < 32767 )
{
/* Increase by 100% */
return p_block;
}
+/*
+ * rtp_ChainInsert - insert a p_block in the chain and
+ * look at the sequence numbers.
+ */
+static inline vlc_bool_t rtp_ChainInsert( access_t *p_access, block_t *p_block )
+{
+ access_sys_t *p_sys = (access_sys_t *) p_access->p_sys;
+ block_t *p_prev = NULL;
+ block_t *p = p_sys->p_end;
+ uint16_t i_new = (uint16_t) p_block->i_dts;
+ uint16_t i_tmp = 0;
+
+ if( !p_sys->p_list )
+ {
+ p_sys->p_list = p_block;
+ p_sys->p_end = p_block;
+ return VLC_TRUE;
+ }
+ /* walk through the queue from top down since the new packet is in
+ most cases just appended to the end */
+
+ for( ;; )
+ {
+ i_tmp = i_new - (uint16_t) p->i_dts;
+
+ if( !i_tmp ) /* trash duplicate */
+ break;
+
+ if ( i_tmp < 32768 )
+ { /* insert after this block ( i_new > p->i_dts ) */
+ p_block->p_next = p->p_next;
+ p->p_next = p_block;
+ p_block->p_prev = p;
+ if (p_prev)
+ {
+ p_prev->p_prev = p_block;
+ msg_Dbg(p_access, "RTP reordering: insert after %d, new %d",
+ (uint16_t) p->i_dts, i_new );
+ }
+ else
+ {
+ p_sys->p_end = p_block;
+ }
+ return VLC_TRUE;
+ }
+ if( p == p_sys->p_list )
+ { /* we've reached bottom of chain */
+ i_tmp = p_sys->i_last_seqno - i_new;
+ if( !p_access->info.b_prebuffered || (i_tmp > 32767) )
+ {
+ msg_Dbg(p_access, "RTP reordering: prepend %d before %d",
+ i_new, (uint16_t) p->i_dts );
+ p_block->p_next = p;
+ p->p_prev = p_block;
+ p_sys->p_list = p_block;
+ return VLC_TRUE;
+ }
+
+ if( !i_tmp ) /* trash duplicate */
+ break;
+
+ /* reordering failed - append the packet to the end of queue */
+ msg_Dbg(p_access, "RTP: sequence changed (or buffer too small) "
+ "new: %d, buffer %d...%d", i_new, (uint16_t) p->i_dts,
+ (uint16_t) p_sys->p_end->i_dts);
+ p_sys->p_end->p_next = p_block;
+ p_block->p_prev = p_sys->p_end;
+ p_sys->p_end = p_block;
+ return VLC_TRUE;
+ }
+ p_prev = p;
+ p = p->p_prev;
+ }
+ block_Release( p_block );
+ return VLC_FALSE;
+}
+
/*****************************************************************************
* BlockParseRTP/BlockRTP:
*****************************************************************************/
static block_t *BlockParseRTP( access_t *p_access, block_t *p_block )
{
- int i_rtp_version;
- int i_CSRC_count;
- int i_payload_type;
- int i_skip = 0;
- int i_sequence_number = 0;
- int i_extention_flag;
- int i_extention_length = 0;
- int i_sequence_expected;
+ int i_rtp_version;
+ int i_CSRC_count;
+ int i_payload_type;
+ int i_skip = 0;
+ int i_extension_flag = 0;
+ int i_extension_length = 0;
+ uint16_t i_sequence_number = 0;
if( p_block == NULL )
return NULL;
goto trash;
/* Parse the header and make some verifications.
- * See RFC 1889 & RFC 2250. */
+ * See RFC 3550. */
i_rtp_version = ( p_block->p_buffer[0] & 0xC0 ) >> 6;
i_CSRC_count = p_block->p_buffer[0] & 0x0F;
- i_extention_flag = p_block->p_buffer[0] & 0x10;
+ i_extension_flag = p_block->p_buffer[0] & 0x10;
i_payload_type = p_block->p_buffer[1] & 0x7F;
i_sequence_number = (p_block->p_buffer[2] << 8 ) + p_block->p_buffer[3];
- if ( i_rtp_version != 2 )
+ if( i_rtp_version != 2 )
msg_Dbg( p_access, "RTP version is %u, should be 2", i_rtp_version );
- if( i_payload_type == 14 )
+ if( i_payload_type == 14 || i_payload_type == 32)
i_skip = 4;
- else if( i_payload_type != 33 && i_payload_type != 32 )
+ else if( i_payload_type != 33 )
msg_Dbg( p_access, "unsupported RTP payload type (%u)", i_payload_type );
- if( i_extention_flag )
- i_extention_length = 4 +
+ if( i_extension_flag )
+ i_extension_length = 4 +
4 * ( (p_block->p_buffer[14] << 8) + p_block->p_buffer[15] );
- /* Skip header + CSRC extension field n*(32 bits) + extention */
- i_skip += RTP_HEADER_LEN + 4*i_CSRC_count + i_extention_length;
+ /* Skip header + CSRC extension field n*(32 bits) + extension */
+ i_skip += RTP_HEADER_LEN + 4*i_CSRC_count + i_extension_length;
if( i_skip >= p_block->i_buffer )
goto trash;
- /* Return the packet without the RTP header. */
+ /* Return the packet without the RTP header, remember seqno in i_dts */
p_block->i_buffer -= i_skip;
p_block->p_buffer += i_skip;
+ p_block->i_dts = (mtime_t) i_sequence_number;
-#define RTP_SEQ_NUM_SIZE 65536
-#define RTP_SEQ_MAX_NO_DELTA 50
- /* Detect RTP packet loss through tracking sequence numbers.
- * See RFC 1889. */
- if( p_access->p_sys->i_sequence_number == -1 )
- p_access->p_sys->i_sequence_number =
- (i_sequence_number - 1 + RTP_SEQ_NUM_SIZE ) % RTP_SEQ_NUM_SIZE;
-
- i_sequence_expected = (p_access->p_sys->i_sequence_number + 1) % RTP_SEQ_NUM_SIZE;
-
- if( i_sequence_expected != i_sequence_number )
+#if 0
+ /* Emulate packet loss */
+ if ( (i_sequence_number % 4000) == 0)
{
- if( ((p_access->p_sys->i_sequence_number - i_sequence_number + RTP_SEQ_NUM_SIZE) % RTP_SEQ_NUM_SIZE) < RTP_SEQ_MAX_NO_DELTA )
- {
- msg_Warn( p_access, "Trashing reordered/duplicate RTP packet, expected sequence number %d got %d",
- i_sequence_expected, i_sequence_number );
- block_Release( p_block );
- return NULL;
- }
-
- msg_Warn( p_access,
- "RTP packet(s) lost, expected sequence number %d got %d",
- i_sequence_expected, i_sequence_number );
- /* Mark transport error in the first TS packet in the RTP stream. */
- if( i_payload_type == 33 && p_block->p_buffer[0] == 0x47 )
- p_block->p_buffer[1] |= 0x80;
+ msg_Warn( p_access, "Emulating packet drop" );
+ block_Release( p_block );
+ return NULL;
}
- p_access->p_sys->i_sequence_number = i_sequence_number;
-#undef RTP_SEQ_MAX_NO_DELTA
-#undef RTP_SEQ_NUM_SIZE
+#endif
+
return p_block;
+
trash:
msg_Warn( p_access, "received a too short packet for RTP" );
block_Release( p_block );
return NULL;
}
+static block_t *BlockPrebufferRTP( access_t *p_access, block_t *p_block )
+{
+ access_sys_t *p_sys = p_access->p_sys;
+ int64_t i_first = mdate();
+ int i_count = 0;
+ block_t *p = p_block;
+
+ for( ;; )
+ {
+ int64_t i_date = mdate();
+
+ if( p && rtp_ChainInsert( p_access, p ))
+ i_count++;
+
+ /* Require at least 3 packets in the buffer */
+ if( i_count > 3 && (i_date - i_first) > p_sys->i_rtp_late )
+ break;
+
+ p = BlockParseRTP( p_access, BlockUDP( p_access ));
+ if( !p && (i_date - i_first) > p_sys->i_rtp_late )
+ {
+ msg_Err( p_access, "Error in RTP prebuffering!" );
+ break;
+ }
+ }
+
+ msg_Dbg( p_access, "RTP: prebuffered %d packets", i_count - 1 );
+ p_access->info.b_prebuffered = VLC_TRUE;
+ p = p_sys->p_list;
+ p_sys->p_list = p_sys->p_list->p_next;
+ p_sys->i_last_seqno = (uint16_t) p->i_dts;
+ p->p_next = NULL;
+ return p;
+}
+
static block_t *BlockRTP( access_t *p_access )
{
- block_t *p_block = BlockUDP( p_access );
+ access_sys_t *p_sys = p_access->p_sys;
+ block_t *p;
- if ( p_block != NULL )
- return BlockParseRTP( p_access, p_block );
- else
+again:
+ p = BlockParseRTP( p_access, BlockUDP( p_access ));
+
+ if ( !p )
return NULL;
+
+ if ( !p_access->info.b_prebuffered )
+ return BlockPrebufferRTP( p_access, p );
+
+ if( !rtp_ChainInsert( p_access, p ))
+ goto again;
+
+ p = p_sys->p_list;
+ p_sys->p_list = p_sys->p_list->p_next;
+ p_sys->i_last_seqno++;
+ if( p_sys->i_last_seqno != (uint16_t) p->i_dts )
+ {
+ msg_Dbg( p_access, "RTP: packet(s) lost, expected %d, got %d",
+ p_sys->i_last_seqno, (uint16_t) p->i_dts );
+ p_sys->i_last_seqno = (uint16_t) p->i_dts;
+ }
+ p->p_next = NULL;
+ return p;
}
/*****************************************************************************
return p_block;
/* Parse the header and make some verifications.
- * See RFC 1889 & RFC 2250. */
+ * See RFC 3550. */
i_rtp_version = ( p_block->p_buffer[0] & 0xC0 ) >> 6;
i_CSRC_count = ( p_block->p_buffer[0] & 0x0F );
return p_block;
}
+ if( !BlockParseRTP( p_access, p_block )) return NULL;
+
p_access->pf_block = BlockRTP;
- return BlockParseRTP( p_access, p_block );
+ return BlockPrebufferRTP( p_access, p_block );
}
projects / vlc / blobdiff