[MPlayer-cvslog] r18805 - trunk/libmpdemux/rtp.c
nicodvb
subversion at mplayerhq.hu
Sat Jun 24 11:10:06 CEST 2006
Author: nicodvb
Date: Sat Jun 24 11:10:06 2006
New Revision: 18805
Modified:
trunk/libmpdemux/rtp.c
Log:
rtp reordering of packets; patch by Ernitron (ernitron at fastwebnet.it)
Modified: trunk/libmpdemux/rtp.c
==============================================================================
--- trunk/libmpdemux/rtp.c (original)
+++ trunk/libmpdemux/rtp.c Sat Jun 24 11:10:06 2006
@@ -32,25 +32,175 @@
extern int network_bandwidth;
-int read_rtp_from_server(int fd, char *buffer, int length) {
+
+#define DEBUG 1
+#include "../mp_msg.h"
+#include "rtp.h"
+
+// RTP reorder routines
+// Also handling of repeated UDP packets (a bug of ExtremeNetworks switches firmware)
+// rtpreord procedures
+// write rtp packets in cache
+// get rtp packets reordered
+
+#define MAXRTPPACKETSIN 32 // The number of max packets being reordered
+
+struct rtpbuffer
+{
+ unsigned char data[MAXRTPPACKETSIN][STREAM_BUFFER_SIZE];
+ unsigned short seq[MAXRTPPACKETSIN];
+ unsigned short len[MAXRTPPACKETSIN];
+ unsigned short first;
+};
+static struct rtpbuffer rtpbuf;
+
+// RTP Reordering functions
+// Algorithm works as follows:
+// If next packet is in sequence just copy it to buffer
+// Otherwise copy it in cache according to its sequence number
+// Cache is a circular array where "rtpbuf.first" points to next sequence slot
+// and keeps track of expected sequence
+
+// Initialize rtp cache
+static void rtp_cache_reset(unsigned short seq)
+{
+ int i;
+
+ rtpbuf.first = 0;
+ rtpbuf.seq[0] = ++seq;
+
+ for (i=0; i<MAXRTPPACKETSIN; i++) {
+ rtpbuf.len[i] = 0;
+ }
+}
+
+// Write in a cache the rtp packet in right rtp sequence order
+static int rtp_cache(int fd, char *buffer, int length)
+{
struct rtpheader rh;
+ int newseq;
char *data;
- int len;
- static int got_first = 0;
- static unsigned short sequence;
-
- if( buffer==NULL || length<0 ) return -1;
-
- getrtp2(fd, &rh, &data, &len);
- if( got_first && rh.b.sequence != (unsigned short)(sequence+1) )
- mp_msg(MSGT_NETWORK,MSGL_ERR,"RTP packet sequence error! Expected: %d, received: %d\n",
- sequence+1, rh.b.sequence);
- got_first = 1;
- sequence = rh.b.sequence;
- memcpy(buffer, data, len);
- return(len);
+ unsigned short seq;
+ static int is_first = 1;
+
+ getrtp2(fd, &rh, &data, &length);
+ seq = rh.b.sequence;
+
+ newseq = seq - rtpbuf.seq[rtpbuf.first];
+
+ if ((newseq == 0) || is_first)
+ {
+ is_first = 0;
+
+ //mp_msg(MSGT_NETWORK, MSGL_DBG4, "RTP (seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq);
+ rtpbuf.first = ( 1 + rtpbuf.first ) % MAXRTPPACKETSIN;
+ rtpbuf.seq[rtpbuf.first] = ++seq;
+ goto feed;
+ }
+
+ if (newseq > MAXRTPPACKETSIN)
+ {
+ mp_msg(MSGT_NETWORK, MSGL_DBG2, "Overrun(seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq);
+ rtp_cache_reset(seq);
+ goto feed;
+ }
+
+ if (newseq < 0)
+ {
+ int i;
+
+ // Is it a stray packet re-sent to network?
+ for (i=0; i<MAXRTPPACKETSIN; i++) {
+ if (rtpbuf.seq[i] == seq) {
+ mp_msg(MSGT_NETWORK, MSGL_ERR, "Stray packet (seq[%d]=%d seq=%d, newseq=%d found at %d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq, i);
+ return 0; // Yes, it is!
+ }
+ }
+ // Some heuristic to decide when to drop packet or to restart everything
+ if (newseq > -(3 * MAXRTPPACKETSIN)) {
+ mp_msg(MSGT_NETWORK, MSGL_ERR, "Too Old packet (seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq);
+ return 0; // Yes, it is!
+ }
+
+ mp_msg(MSGT_NETWORK, MSGL_ERR, "Underrun(seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq);
+
+ rtp_cache_reset(seq);
+ goto feed;
+ }
+
+ mp_msg(MSGT_NETWORK, MSGL_DBG4, "Out of Seq (seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq);
+ newseq = ( newseq + rtpbuf.first ) % MAXRTPPACKETSIN;
+ memcpy (rtpbuf.data[newseq], data, length);
+ rtpbuf.len[newseq] = length;
+ rtpbuf.seq[newseq] = seq;
+
+ return 0;
+
+feed:
+ memcpy (buffer, data, length);
+ return length;
}
+// Get next packet in cache
+// Look in cache to get first packet in sequence
+static int rtp_get_next(int fd, char *buffer, int length)
+{
+ int i;
+ unsigned short nextseq;
+
+ // If we have empty buffer we loop to fill it
+ for (i=0; i < MAXRTPPACKETSIN -3; i++) {
+ if (rtpbuf.len[rtpbuf.first] != 0) break;
+
+ length = rtp_cache(fd, buffer, length) ;
+
+ // returns on first packet in sequence
+ if (length > 0) {
+ //mp_msg(MSGT_NETWORK, MSGL_DBG4, "Getting rtp [%d] %hu\n", i, rtpbuf.first);
+ return length;
+ } else if (length < 0) break;
+
+ // Only if length == 0 loop continues!
+ }
+
+ i = rtpbuf.first;
+ while (rtpbuf.len[i] == 0) {
+ mp_msg(MSGT_NETWORK, MSGL_ERR, "Lost packet %hu\n", rtpbuf.seq[i]);
+ i = ( 1 + i ) % MAXRTPPACKETSIN;
+ if (rtpbuf.first == i) break;
+ }
+ rtpbuf.first = i;
+
+ // Copy next non empty packet from cache
+ mp_msg(MSGT_NETWORK, MSGL_DBG4, "Getting rtp from cache [%d] %hu\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first]);
+ memcpy (buffer, rtpbuf.data[rtpbuf.first], rtpbuf.len[rtpbuf.first]);
+ length = rtpbuf.len[rtpbuf.first]; // can be zero?
+
+ // Reset fisrt slot and go next in cache
+ rtpbuf.len[rtpbuf.first] = 0;
+ nextseq = rtpbuf.seq[rtpbuf.first];
+ rtpbuf.first = ( 1 + rtpbuf.first ) % MAXRTPPACKETSIN;
+ rtpbuf.seq[rtpbuf.first] = nextseq + 1;
+
+ return length;
+}
+
+
+// Read next rtp packet using cache
+int read_rtp_from_server(int fd, char *buffer, int length) {
+ // Following test is ASSERT (i.e. uneuseful if code is correct)
+ if(buffer==NULL || length<STREAM_BUFFER_SIZE) {
+ mp_msg(MSGT_NETWORK, MSGL_ERR, "RTP buffer invalid; no data return from network\n");
+ return 0;
+ }
+
+ // loop just to skip empty packets
+ while ((length = rtp_get_next(fd, buffer, length)) == 0) {
+ mp_msg(MSGT_NETWORK, MSGL_ERR, "Got empty packet from RTP cache!?\n");
+ }
+
+ return(length);
+}
// Start listening on a UDP port. If multicast, join the group.
static int rtp_open_socket( URL_t *url ) {
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