4 Protocols are configured elements in Libav which allow to access
5 resources which require the use of a particular protocol.
7 When you configure your Libav build, all the supported protocols are
8 enabled by default. You can list all available ones using the
9 configure option "--list-protocols".
11 You can disable all the protocols using the configure option
12 "--disable-protocols", and selectively enable a protocol using the
13 option "--enable-protocol=@var{PROTOCOL}", or you can disable a
14 particular protocol using the option
15 "--disable-protocol=@var{PROTOCOL}".
17 The option "-protocols" of the ff* tools will display the list of
20 A description of the currently available protocols follows.
24 Read Apple HTTP Live Streaming compliant segmented stream as
25 a uniform one. The M3U8 playlists describing the segments can be
26 remote HTTP resources or local files, accessed using the standard
28 HTTP is default, specific protocol can be declared by specifying
29 "+@var{proto}" after the applehttp URI scheme name, where @var{proto}
30 is either "file" or "http".
33 applehttp://host/path/to/remote/resource.m3u8
34 applehttp+http://host/path/to/remote/resource.m3u8
35 applehttp+file://path/to/local/resource.m3u8
40 Physical concatenation protocol.
42 Allow to read and seek from many resource in sequence as if they were
45 A URL accepted by this protocol has the syntax:
47 concat:@var{URL1}|@var{URL2}|...|@var{URLN}
50 where @var{URL1}, @var{URL2}, ..., @var{URLN} are the urls of the
51 resource to be concatenated, each one possibly specifying a distinct
54 For example to read a sequence of files @file{split1.mpeg},
55 @file{split2.mpeg}, @file{split3.mpeg} with @file{avplay} use the
58 avplay concat:split1.mpeg\|split2.mpeg\|split3.mpeg
61 Note that you may need to escape the character "|" which is special for
68 Allow to read from or read to a file.
70 For example to read from a file @file{input.mpeg} with @command{avconv}
73 avconv -i file:input.mpeg output.mpeg
76 The ff* tools default to the file protocol, that is a resource
77 specified with the name "FILE.mpeg" is interpreted as the URL
86 HTTP (Hyper Text Transfer Protocol).
90 MMS (Microsoft Media Server) protocol over TCP.
94 MMS (Microsoft Media Server) protocol over HTTP.
96 The required syntax is:
98 mmsh://@var{server}[:@var{port}][/@var{app}][/@var{playpath}]
105 Computes the MD5 hash of the data to be written, and on close writes
106 this to the designated output or stdout if none is specified. It can
107 be used to test muxers without writing an actual file.
109 Some examples follow.
111 # Write the MD5 hash of the encoded AVI file to the file output.avi.md5.
112 avconv -i input.flv -f avi -y md5:output.avi.md5
114 # Write the MD5 hash of the encoded AVI file to stdout.
115 avconv -i input.flv -f avi -y md5:
118 Note that some formats (typically MOV) require the output protocol to
119 be seekable, so they will fail with the MD5 output protocol.
123 UNIX pipe access protocol.
125 Allow to read and write from UNIX pipes.
127 The accepted syntax is:
132 @var{number} is the number corresponding to the file descriptor of the
133 pipe (e.g. 0 for stdin, 1 for stdout, 2 for stderr). If @var{number}
134 is not specified, by default the stdout file descriptor will be used
135 for writing, stdin for reading.
137 For example to read from stdin with @command{avconv}:
139 cat test.wav | avconv -i pipe:0
140 # ...this is the same as...
141 cat test.wav | avconv -i pipe:
144 For writing to stdout with @command{avconv}:
146 avconv -i test.wav -f avi pipe:1 | cat > test.avi
147 # ...this is the same as...
148 avconv -i test.wav -f avi pipe: | cat > test.avi
151 Note that some formats (typically MOV), require the output protocol to
152 be seekable, so they will fail with the pipe output protocol.
156 Real-Time Messaging Protocol.
158 The Real-Time Messaging Protocol (RTMP) is used for streaming multimedia
159 content across a TCP/IP network.
161 The required syntax is:
163 rtmp://@var{server}[:@var{port}][/@var{app}][/@var{playpath}]
166 The accepted parameters are:
170 The address of the RTMP server.
173 The number of the TCP port to use (by default is 1935).
176 It is the name of the application to access. It usually corresponds to
177 the path where the application is installed on the RTMP server
178 (e.g. @file{/ondemand/}, @file{/flash/live/}, etc.).
181 It is the path or name of the resource to play with reference to the
182 application specified in @var{app}, may be prefixed by "mp4:".
186 For example to read with @file{avplay} a multimedia resource named
187 "sample" from the application "vod" from an RTMP server "myserver":
189 avplay rtmp://myserver/vod/sample
192 @section rtmp, rtmpe, rtmps, rtmpt, rtmpte
194 Real-Time Messaging Protocol and its variants supported through
197 Requires the presence of the librtmp headers and library during
198 configuration. You need to explicitly configure the build with
199 "--enable-librtmp". If enabled this will replace the native RTMP
202 This protocol provides most client functions and a few server
203 functions needed to support RTMP, RTMP tunneled in HTTP (RTMPT),
204 encrypted RTMP (RTMPE), RTMP over SSL/TLS (RTMPS) and tunneled
205 variants of these encrypted types (RTMPTE, RTMPTS).
207 The required syntax is:
209 @var{rtmp_proto}://@var{server}[:@var{port}][/@var{app}][/@var{playpath}] @var{options}
212 where @var{rtmp_proto} is one of the strings "rtmp", "rtmpt", "rtmpe",
213 "rtmps", "rtmpte", "rtmpts" corresponding to each RTMP variant, and
214 @var{server}, @var{port}, @var{app} and @var{playpath} have the same
215 meaning as specified for the RTMP native protocol.
216 @var{options} contains a list of space-separated options of the form
219 See the librtmp manual page (man 3 librtmp) for more information.
221 For example, to stream a file in real-time to an RTMP server using
224 avconv -re -i myfile -f flv rtmp://myserver/live/mystream
227 To play the same stream using @file{avplay}:
229 avplay "rtmp://myserver/live/mystream live=1"
238 RTSP is not technically a protocol handler in libavformat, it is a demuxer
239 and muxer. The demuxer supports both normal RTSP (with data transferred
240 over RTP; this is used by e.g. Apple and Microsoft) and Real-RTSP (with
241 data transferred over RDT).
243 The muxer can be used to send a stream using RTSP ANNOUNCE to a server
244 supporting it (currently Darwin Streaming Server and Mischa Spiegelmock's
245 @uref{http://github.com/revmischa/rtsp-server, RTSP server}).
247 The required syntax for a RTSP url is:
249 rtsp://@var{hostname}[:@var{port}]/@var{path}
252 The following options (set on the @command{avconv}/@file{avplay} command
253 line, or set in code via @code{AVOption}s or in @code{avformat_open_input}),
256 Flags for @code{rtsp_transport}:
261 Use UDP as lower transport protocol.
264 Use TCP (interleaving within the RTSP control channel) as lower
268 Use UDP multicast as lower transport protocol.
271 Use HTTP tunneling as lower transport protocol, which is useful for
275 Multiple lower transport protocols may be specified, in that case they are
276 tried one at a time (if the setup of one fails, the next one is tried).
277 For the muxer, only the @code{tcp} and @code{udp} options are supported.
279 Flags for @code{rtsp_flags}:
283 Accept packets only from negotiated peer address and port.
286 When receiving data over UDP, the demuxer tries to reorder received packets
287 (since they may arrive out of order, or packets may get lost totally). In
288 order for this to be enabled, a maximum delay must be specified in the
289 @code{max_delay} field of AVFormatContext.
291 When watching multi-bitrate Real-RTSP streams with @file{avplay}, the
292 streams to display can be chosen with @code{-vst} @var{n} and
293 @code{-ast} @var{n} for video and audio respectively, and can be switched
294 on the fly by pressing @code{v} and @code{a}.
296 Example command lines:
298 To watch a stream over UDP, with a max reordering delay of 0.5 seconds:
301 avplay -max_delay 500000 -rtsp_transport udp rtsp://server/video.mp4
304 To watch a stream tunneled over HTTP:
307 avplay -rtsp_transport http rtsp://server/video.mp4
310 To send a stream in realtime to a RTSP server, for others to watch:
313 avconv -re -i @var{input} -f rtsp -muxdelay 0.1 rtsp://server/live.sdp
318 Session Announcement Protocol (RFC 2974). This is not technically a
319 protocol handler in libavformat, it is a muxer and demuxer.
320 It is used for signalling of RTP streams, by announcing the SDP for the
321 streams regularly on a separate port.
325 The syntax for a SAP url given to the muxer is:
327 sap://@var{destination}[:@var{port}][?@var{options}]
330 The RTP packets are sent to @var{destination} on port @var{port},
331 or to port 5004 if no port is specified.
332 @var{options} is a @code{&}-separated list. The following options
337 @item announce_addr=@var{address}
338 Specify the destination IP address for sending the announcements to.
339 If omitted, the announcements are sent to the commonly used SAP
340 announcement multicast address 224.2.127.254 (sap.mcast.net), or
341 ff0e::2:7ffe if @var{destination} is an IPv6 address.
343 @item announce_port=@var{port}
344 Specify the port to send the announcements on, defaults to
345 9875 if not specified.
348 Specify the time to live value for the announcements and RTP packets,
351 @item same_port=@var{0|1}
352 If set to 1, send all RTP streams on the same port pair. If zero (the
353 default), all streams are sent on unique ports, with each stream on a
354 port 2 numbers higher than the previous.
355 VLC/Live555 requires this to be set to 1, to be able to receive the stream.
356 The RTP stack in libavformat for receiving requires all streams to be sent
360 Example command lines follow.
362 To broadcast a stream on the local subnet, for watching in VLC:
365 avconv -re -i @var{input} -f sap sap://224.0.0.255?same_port=1
368 Similarly, for watching in avplay:
371 avconv -re -i @var{input} -f sap sap://224.0.0.255
374 And for watching in avplay, over IPv6:
377 avconv -re -i @var{input} -f sap sap://[ff0e::1:2:3:4]
382 The syntax for a SAP url given to the demuxer is:
384 sap://[@var{address}][:@var{port}]
387 @var{address} is the multicast address to listen for announcements on,
388 if omitted, the default 224.2.127.254 (sap.mcast.net) is used. @var{port}
389 is the port that is listened on, 9875 if omitted.
391 The demuxers listens for announcements on the given address and port.
392 Once an announcement is received, it tries to receive that particular stream.
394 Example command lines follow.
396 To play back the first stream announced on the normal SAP multicast address:
402 To play back the first stream announced on one the default IPv6 SAP multicast address:
405 avplay sap://[ff0e::2:7ffe]
410 Trasmission Control Protocol.
412 The required syntax for a TCP url is:
414 tcp://@var{hostname}:@var{port}[?@var{options}]
420 Listen for an incoming connection
423 avconv -i @var{input} -f @var{format} tcp://@var{hostname}:@var{port}?listen
424 avplay tcp://@var{hostname}:@var{port}
431 User Datagram Protocol.
433 The required syntax for a UDP url is:
435 udp://@var{hostname}:@var{port}[?@var{options}]
438 @var{options} contains a list of &-seperated options of the form @var{key}=@var{val}.
439 Follow the list of supported options.
443 @item buffer_size=@var{size}
444 set the UDP buffer size in bytes
446 @item localport=@var{port}
447 override the local UDP port to bind with
449 @item localaddr=@var{addr}
450 Choose the local IP address. This is useful e.g. if sending multicast
451 and the host has multiple interfaces, where the user can choose
452 which interface to send on by specifying the IP address of that interface.
454 @item pkt_size=@var{size}
455 set the size in bytes of UDP packets
457 @item reuse=@var{1|0}
458 explicitly allow or disallow reusing UDP sockets
461 set the time to live value (for multicast only)
463 @item connect=@var{1|0}
464 Initialize the UDP socket with @code{connect()}. In this case, the
465 destination address can't be changed with ff_udp_set_remote_url later.
466 If the destination address isn't known at the start, this option can
467 be specified in ff_udp_set_remote_url, too.
468 This allows finding out the source address for the packets with getsockname,
469 and makes writes return with AVERROR(ECONNREFUSED) if "destination
470 unreachable" is received.
471 For receiving, this gives the benefit of only receiving packets from
472 the specified peer address/port.
475 Some usage examples of the udp protocol with @command{avconv} follow.
477 To stream over UDP to a remote endpoint:
479 avconv -i @var{input} -f @var{format} udp://@var{hostname}:@var{port}
482 To stream in mpegts format over UDP using 188 sized UDP packets, using a large input buffer:
484 avconv -i @var{input} -f mpegts udp://@var{hostname}:@var{port}?pkt_size=188&buffer_size=65535
487 To receive over UDP from a remote endpoint:
489 avconv -i udp://[@var{multicast-address}]:@var{port}