188
* Layout of the header (in bits):
190
* Flag indicating whether this header includes a length field;
191
* this can be used to concatenate multiple RDT packets in a
192
* single UDP/TCP data frame and is used to precede RDT data
193
* by stream status packets
195
* Flag indicating whether this header includes a "reliable
196
* sequence number"; these are apparently sequence numbers of
197
* data packets alone. For data packets, this flag is always
198
* set, according to the Real documentation [1]
200
* ID of a set of streams of identical content, possibly with
201
* different codecs or bitrates
203
* Flag set for certain streams deemed less tolerable for packet
206
* Packet sequence number; if >=0xFF00, this is a non-data packet
207
* containing stream status info, the second byte indicates the
208
* type of status packet (see wireshark docs / source code [2])
209
* if (len_included) {
212
* packet_len = remainder of UDP/TCP frame
215
* Back-to-Back flag; used for timing, set for one in every 10
216
* packets, according to the Real documentation [1]
218
* Slow-data flag; currently unused, according to Real docs [1]
220
* ID of the stream within this particular set of streams
222
* Non-keyframe flag (unset if packet belongs to a keyframe)
223
* 32: timestamp (PTS)
224
* if (set_id == 0x1F) {
225
* 16: set_id (extended set-of-streams ID; see set_id)
227
* if (need_reliable) {
228
* 16: reliable_seq_no
229
* Reliable sequence number (see need_reliable)
231
* if (stream_id == 0x3F) {
232
* 16: stream_id (extended stream ID; see stream_id)
234
* [1] https://protocol.helixcommunity.org/files/2005/devdocs/RDT_Feature_Level_20.txt
235
* [2] http://www.wireshark.org/docs/dfref/r/rdt.html and
236
* http://anonsvn.wireshark.org/viewvc/trunk/epan/dissectors/packet-rdt.c
187
238
if (sn) *sn = (buf[0]>>1) & 0x1f;
188
239
if (seq) *seq = AV_RB16(buf+1);
189
240
if (ts) *ts = AV_RB32(buf+4);