Document the SAP muxer

Originally committed as revision 25427 to svn://svn.ffmpeg.org/ffmpeg/trunk
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Martin Storsjö 2010-10-09 18:50:02 +00:00
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@ -287,6 +287,54 @@ To send a stream in realtime to a RTSP server, for others to watch:
ffmpeg -re -i @var{input} -f rtsp -muxdelay 0.1 rtsp://server/live.sdp
@end example
@section sap
Session Announcement Protocol (RFC 2974). This is not technically a
protocol handler in libavformat, it is a muxer.
It is used for signalling of RTP streams, by announcing the SDP for the
streams regularly on a separate port.
The syntax for a SAP url given to the muxer is:
@example
sap://@var{destination}[:@var{port}][?@var{options}]
@end example
The RTP packets are sent to @var{destination} on port @var{port},
or to port 5004 if no port is specified.
@var{options} is a @code{&}-separated list. The following options
are supported:
@table @option
@item announce_addr=@var{address}
Specify the destination IP address for sending the announcements to.
If omitted, the announcements are sent to the commonly used SAP
announcement multicast address 224.2.127.254 (sap.mcast.net), or
ff0e::2:7ffe if @var{destination} is an IPv6 address.
@item announce_port=@var{port}
Specify the port to send the announcements on, defaults to
9875 if not specified.
@item ttl=@var{ttl}
Specify the time to live value for the announcements and RTP packets,
defaults to 255.
@item same_port=@var{0|1}
If set to 1, send all RTP streams on the same port pair. If zero (the
default), all streams are sent on unique ports, with each stream on a
port 2 numbers higher than the previous.
VLC/Live555 requires this to be set to 1, to be able to receive the stream.
@end table
Example command lines follow.
To broadcast a stream on the local subnet, for watching in VLC:
@example
ffmpeg -re -i @var{input} -f sap sap://224.0.0.255?same_port=1
@end example
@section tcp
Trasmission Control Protocol.