This patch refactors RDT packet header parsing so that it can be used in

rtsp.c to detect the ID of the packet source also in case of TCP streams.
This allows proper playback of RDT streams with multiple stream types, e.g.
audio + video. Accepted by LucaB in "RDT/Realmedia patches #2" thread on ML.

Originally committed as revision 15496 to svn://svn.ffmpeg.org/ffmpeg/trunk

diff --git a/libavformat/rdt.c b/libavformat/rdt.c
index c1238b2d46c1dcf6f08d5c4776b683037b7f491b..0dd9a6ef8742eb33042b627aefce44d46272931c 100644 (file)
--- a/libavformat/rdt.c
+++ b/libavformat/rdt.c
@@ -140,27 +140,25 @@ rdt_load_mdpr (rdt_data *rdt, AVStream *st, int rule_nr)
  * Actual data handling.
  */
 
-static int rdt_parse_header(struct RTPDemuxContext *s, const uint8_t *buf,
-                            int len, int *seq, uint32_t *timestamp, int *flags)
+int
+ff_rdt_parse_header(const uint8_t *buf, int len,
+                    int *sn, int *seq, int *rn, uint32_t *ts)
 {
-    rdt_data *rdt = s->dynamic_protocol_context;
-    int consumed = 0, sn;
+    int consumed = 10;
 
-    if (buf[0] < 0x40 || buf[0] > 0x42) {
+    if (len > 0 && (buf[0] < 0x40 || buf[0] > 0x42)) {
         buf += 9;
         len -= 9;
         consumed += 9;
     }
-    sn = (buf[0]>>1) & 0x1f;
-    *seq = AV_RB16(buf+1);
-    *timestamp = AV_RB32(buf+4);
-    if (!(buf[3] & 1) && (sn != rdt->prev_sn || *timestamp != rdt->prev_ts)) {
-        *flags |= PKT_FLAG_KEY;
-        rdt->prev_sn = sn;
-        rdt->prev_ts = *timestamp;
-    }
+    if (len < 10)
+        return -1;
+    if (sn)  *sn  = (buf[0]>>1) & 0x1f;
+    if (seq) *seq = AV_RB16(buf+1);
+    if (ts)  *ts  = AV_RB32(buf+4);
+    if (rn)  *rn  = buf[3] & 0x3f;
 
-    return consumed + 10;
+    return consumed;
 }
 
 /**< return 0 on packet, no more left, 1 on packet, 1 on partial packet... */
@@ -208,7 +206,8 @@ int
 ff_rdt_parse_packet(RTPDemuxContext *s, AVPacket *pkt,
                     const uint8_t *buf, int len)
 {
-    int seq, flags = 0;
+    rdt_data *rdt = s->dynamic_protocol_context;
+    int seq, flags = 0, rule, sn;
     uint32_t timestamp;
     int rv= 0;
 
@@ -221,9 +220,14 @@ ff_rdt_parse_packet(RTPDemuxContext *s, AVPacket *pkt,
 
     if (len < 12)
         return -1;
-    rv = rdt_parse_header(s, buf, len, &seq, &timestamp, &flags);
+    rv = ff_rdt_parse_header(buf, len, &sn, &seq, &rule, &timestamp);
     if (rv < 0)
         return rv;
+    if (!(rule & 1) && (sn != rdt->prev_sn || timestamp != rdt->prev_ts)) {
+        flags |= PKT_FLAG_KEY;
+        rdt->prev_sn = sn;
+        rdt->prev_ts = timestamp;
+    }
     buf += rv;
     len -= rv;
     s->seq = seq;

diff --git a/libavformat/rdt.h b/libavformat/rdt.h
index 5a13127fb5274bbe712e1ce0741f5989dfb74627..2fe11873ac985fba10d0823bc0ea745d09e5c9a7 100644 (file)
--- a/libavformat/rdt.h
+++ b/libavformat/rdt.h
@@ -56,6 +56,20 @@ void ff_rdt_subscribe_rule(char *cmd, int size,
 void ff_rdt_subscribe_rule2(RTPDemuxContext *s, char *cmd, int size,
                             int stream_nr, int rule_nr);
 
+/**
+ * Parse RDT-style packet header.
+ *
+ * @param buf input buffer
+ * @param len length of input buffer
+ * @param sn will be set to the stream number this packet belongs to
+ * @param seq will be set to the sequence number this packet belongs to
+ * @param rn will be set to the rule number this packet belongs to
+ * @param ts will be set to the timestamp of the packet
+ * @return the amount of bytes consumed, or <0 on error
+ */
+int ff_rdt_parse_header(const uint8_t *buf, int len,
+                        int *sn, int *seq, int *rn, uint32_t *ts);
+
 /**
  * Parse RDT-style packet data (header + media data).
  * Usage similar to rtp_parse_packet().

diff --git a/libavformat/rtsp.c b/libavformat/rtsp.c
index b6013de267d9f1e2ba7be43ba6d1f99b15d5bf5a..254931cf3d55628746e0b0cb36bd08e459de5d8c 100644 (file)
--- a/libavformat/rtsp.c
+++ b/libavformat/rtsp.c
@@ -1265,6 +1265,9 @@ static int tcp_read_packet(AVFormatContext *s, RTSPStream **prtsp_st,
     ret = url_readbuf(rt->rtsp_hd, buf, len);
     if (ret != len)
         return -1;
+    if (rt->transport == RTSP_TRANSPORT_RDT &&
+        ff_rdt_parse_header(buf, len, &id, NULL, NULL, NULL) < 0)
+        return -1;
 
     /* find the matching stream */
     for(i = 0; i < rt->nb_rtsp_streams; i++) {