@chapter Protocols
@c man begin PROTOCOLS
-Protocols are configured elements in FFmpeg which allow to access
+Protocols are configured elements in Libav which allow to access
resources which require the use of a particular protocol.
-When you configure your FFmpeg build, all the supported protocols are
+When you configure your Libav build, all the supported protocols are
enabled by default. You can list all available ones using the
configure option "--list-protocols".
A description of the currently available protocols follows.
+@section applehttp
+
+Read Apple HTTP Live Streaming compliant segmented stream as
+a uniform one. The M3U8 playlists describing the segments can be
+remote HTTP resources or local files, accessed using the standard
+file protocol.
+HTTP is default, specific protocol can be declared by specifying
+"+@var{proto}" after the applehttp URI scheme name, where @var{proto}
+is either "file" or "http".
+
+@example
+applehttp://host/path/to/remote/resource.m3u8
+applehttp+http://host/path/to/remote/resource.m3u8
+applehttp+file://path/to/local/resource.m3u8
+@end example
+
@section concat
Physical concatenation protocol.
protocol.
For example to read a sequence of files @file{split1.mpeg},
-@file{split2.mpeg}, @file{split3.mpeg} with @file{ffplay} use the
+@file{split2.mpeg}, @file{split3.mpeg} with @file{avplay} use the
command:
@example
-ffplay concat:split1.mpeg\|split2.mpeg\|split3.mpeg
+avplay concat:split1.mpeg\|split2.mpeg\|split3.mpeg
@end example
Note that you may need to escape the character "|" which is special for
@end table
-For example to read with @file{ffplay} a multimedia resource named
+For example to read with @file{avplay} a multimedia resource named
"sample" from the application "vod" from an RTMP server "myserver":
@example
-ffplay rtmp://myserver/vod/sample
+avplay rtmp://myserver/vod/sample
@end example
@section rtmp, rtmpe, rtmps, rtmpt, rtmpte
ffmpeg -re -i myfile -f flv rtmp://myserver/live/mystream
@end example
-To play the same stream using @file{ffplay}:
+To play the same stream using @file{avplay}:
@example
-ffplay "rtmp://myserver/live/mystream live=1"
+avplay "rtmp://myserver/live/mystream live=1"
@end example
@section rtp
The muxer can be used to send a stream using RTSP ANNOUNCE to a server
supporting it (currently Darwin Streaming Server and Mischa Spiegelmock's
-RTSP server, @url{http://github.com/revmischa/rtsp-server}).
+@uref{http://github.com/revmischa/rtsp-server, RTSP server}).
The required syntax for a RTSP url is:
@example
@item http
Use HTTP tunneling as lower transport protocol, which is useful for
passing proxies.
+
+@item filter_src
+Accept packets only from negotiated peer address and port.
@end table
Multiple lower transport protocols may be specified, in that case they are
order for this to be enabled, a maximum delay must be specified in the
@code{max_delay} field of AVFormatContext.
-When watching multi-bitrate Real-RTSP streams with @file{ffplay}, the
+When watching multi-bitrate Real-RTSP streams with @file{avplay}, the
streams to display can be chosen with @code{-vst} @var{n} and
@code{-ast} @var{n} for video and audio respectively, and can be switched
on the fly by pressing @code{v} and @code{a}.
To watch a stream over UDP, with a max reordering delay of 0.5 seconds:
@example
-ffplay -max_delay 500000 rtsp://server/video.mp4?udp
+avplay -max_delay 500000 rtsp://server/video.mp4?udp
@end example
To watch a stream tunneled over HTTP:
@example
-ffplay rtsp://server/video.mp4?http
+avplay rtsp://server/video.mp4?http
@end example
To send a stream in realtime to a RTSP server, for others to watch:
@section sap
Session Announcement Protocol (RFC 2974). This is not technically a
-protocol handler in libavformat, it is a muxer.
+protocol handler in libavformat, it is a muxer and demuxer.
It is used for signalling of RTP streams, by announcing the SDP for the
streams regularly on a separate port.
+@subsection Muxer
+
The syntax for a SAP url given to the muxer is:
@example
sap://@var{destination}[:@var{port}][?@var{options}]
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.
+The RTP stack in libavformat for receiving requires all streams to be sent
+on unique ports.
@end table
Example command lines follow.
ffmpeg -re -i @var{input} -f sap sap://224.0.0.255?same_port=1
@end example
+Similarly, for watching in avplay:
+
+@example
+ffmpeg -re -i @var{input} -f sap sap://224.0.0.255
+@end example
+
+And for watching in avplay, over IPv6:
+
+@example
+ffmpeg -re -i @var{input} -f sap sap://[ff0e::1:2:3:4]
+@end example
+
+@subsection Demuxer
+
+The syntax for a SAP url given to the demuxer is:
+@example
+sap://[@var{address}][:@var{port}]
+@end example
+
+@var{address} is the multicast address to listen for announcements on,
+if omitted, the default 224.2.127.254 (sap.mcast.net) is used. @var{port}
+is the port that is listened on, 9875 if omitted.
+
+The demuxers listens for announcements on the given address and port.
+Once an announcement is received, it tries to receive that particular stream.
+
+Example command lines follow.
+
+To play back the first stream announced on the normal SAP multicast address:
+
+@example
+avplay sap://
+@end example
+
+To play back the first stream announced on one the default IPv6 SAP multicast address:
+
+@example
+avplay sap://[ff0e::2:7ffe]
+@end example
+
@section tcp
Trasmission Control Protocol.
+The required syntax for a TCP url is:
+@example
+tcp://@var{hostname}:@var{port}[?@var{options}]
+@end example
+
+@table @option
+
+@item listen
+Listen for an incoming connection
+
+@example
+ffmpeg -i @var{input} -f @var{format} tcp://@var{hostname}:@var{port}?listen
+avplay tcp://@var{hostname}:@var{port}
+@end example
+
+@end table
+
@section udp
User Datagram Protocol.
@item connect=@var{1|0}
Initialize the UDP socket with @code{connect()}. In this case, the
-destination address can't be changed with udp_set_remote_url later.
+destination address can't be changed with ff_udp_set_remote_url later.
+If the destination address isn't known at the start, this option can
+be specified in ff_udp_set_remote_url, too.
This allows finding out the source address for the packets with getsockname,
and makes writes return with AVERROR(ECONNREFUSED) if "destination
unreachable" is received.
+For receiving, this gives the benefit of only receiving packets from
+the specified peer address/port.
@end table
Some usage examples of the udp protocol with @file{ffmpeg} follow.
projects / ffmpeg / blobdiff