Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
FFMPEG-PROTOCOLS(1)					     FFMPEG-PROTOCOLS(1)

NAME
     ffmpeg-protocols - FFmpeg protocols

DESCRIPTION
     This document describes the input and output protocols provided by the
     libavformat library.

PROTOCOL OPTIONS
     The libavformat library provides some generic global options, which can be
     set on all the protocols. In addition each protocol may support so-called
     private options, which are specific for that component.

     Options may be set by specifying -option value in the FFmpeg tools, or by
     setting the value explicitly in the "AVFormatContext" options or using the
     libavutil/opt.h API for programmatic use.

     The list of supported options follows:

     protocol_whitelist list (input)
	 Set a ","-separated list of allowed protocols. "ALL" matches all proto-
	 cols. Protocols prefixed by "-" are disabled.	All protocols are al-
	 lowed by default but protocols used by an another protocol (nested pro-
	 tocols) are restricted to a per protocol subset.

PROTOCOLS
     Protocols are configured elements in FFmpeg that enable access to resources
     that require specific protocols.

     When you configure your FFmpeg build, all the supported protocols are en-
     abled by default. You can list all available ones using the configure op-
     tion "--list-protocols".

     You can disable all the protocols using the configure option "--dis-
     able-protocols", and selectively enable a protocol using the option "--en-
     able-protocol=PROTOCOL", or you can disable a particular protocol using the
     option "--disable-protocol=PROTOCOL".

     The option "-protocols" of the ff* tools will display the list of supported
     protocols.

     All protocols accept the following options:

     rw_timeout
	 Maximum time to wait for (network) read/write operations to complete,
	 in microseconds.

     A description of the currently available protocols follows.

   amqp
     Advanced Message Queueing Protocol (AMQP) version 0-9-1 is a broker based
     publish-subscribe communication protocol.

     FFmpeg must be compiled with --enable-librabbitmq to support AMQP. A sepa-
     rate AMQP broker must also be run. An example open-source AMQP broker is
     RabbitMQ.

     After starting the broker, an FFmpeg client may stream data to the broker
     using the command:

	     ffmpeg -re -i input -f mpegts amqp://[[user]:[password]@]hostname[:port][/vhost]

     Where hostname and port (default is 5672) is the address of the broker. The
     client may also set a user/password for authentication. The default for
     both fields is "guest". Name of virtual host on broker can be set with
     vhost. The default value is "/".

     Multiple subscribers may stream from the broker using the command:

	     ffplay amqp://[[user]:[password]@]hostname[:port][/vhost]

     In RabbitMQ all data published to the broker flows through a specific ex-
     change, and each subscribing client has an assigned queue/buffer. When a
     packet arrives at an exchange, it may be copied to a client's queue depend-
     ing on the exchange and routing_key fields.

     The following options are supported:

     exchange
	 Sets the exchange to use on the broker. RabbitMQ has several predefined
	 exchanges: "amq.direct" is the default exchange, where the publisher
	 and subscriber must have a matching routing_key; "amq.fanout" is the
	 same as a broadcast operation (i.e. the data is forwarded to all queues
	 on the fanout exchange independent of the routing_key); and "amq.topic"
	 is similar to "amq.direct", but allows for more complex pattern match-
	 ing (refer to the RabbitMQ documentation).

     routing_key
	 Sets the routing key. The default value is "amqp". The routing key is
	 used on the "amq.direct" and "amq.topic" exchanges to decide whether
	 packets are written to the queue of a subscriber.

     pkt_size
	 Maximum size of each packet sent/received to the broker. Default is
	 131072.  Minimum is 4096 and max is any large value (representable by
	 an int). When receiving packets, this sets an internal buffer size in
	 FFmpeg. It should be equal to or greater than the size of the published
	 packets to the broker. Otherwise the received message may be truncated
	 causing decoding errors.

     connection_timeout
	 The timeout in seconds during the initial connection to the broker. The
	 default value is rw_timeout, or 5 seconds if rw_timeout is not set.

     delivery_mode mode
	 Sets the delivery mode of each message sent to broker.  The following
	 values are accepted:

	 persistent
	     Delivery mode set to "persistent" (2). This is the default value.
	     Messages may be written to the broker's disk depending on its
	     setup.

	 non-persistent
	     Delivery mode set to "non-persistent" (1).  Messages will stay in
	     broker's memory unless the broker is under memory pressure.

   async
     Asynchronous data filling wrapper for input stream.

     Fill data in a background thread, to decouple I/O operation from demux
     thread.

	     async:<URL>
	     async:http://host/resource
	     async:cache:http://host/resource

   bluray
     Read BluRay playlist.

     The accepted options are:

     angle
	 BluRay angle

     chapter
	 Start chapter (1...N)

     playlist
	 Playlist to read (BDMV/PLAYLIST/?????.mpls)

     Examples:

     Read longest playlist from BluRay mounted to /mnt/bluray:

	     bluray:/mnt/bluray

     Read angle 2 of playlist 4 from BluRay mounted to /mnt/bluray, start from
     chapter 2:

	     -playlist 4 -angle 2 -chapter 2 bluray:/mnt/bluray

   cache
     Caching wrapper for input stream.

     Cache the input stream to temporary file. It brings seeking capability to
     live streams.

     The accepted options are:

     read_ahead_limit
	 Amount in bytes that may be read ahead when seeking isn't supported.
	 Range is -1 to INT_MAX.  -1 for unlimited. Default is 65536.

     URL Syntax is

	     cache:<URL>

   concat
     Physical concatenation protocol.

     Read and seek from many resources in sequence as if they were a unique re-
     source.

     A URL accepted by this protocol has the syntax:

	     concat:<URL1>|<URL2>|...|<URLN>

     where URL1, URL2, ..., URLN are the urls of the resource to be concate-
     nated, each one possibly specifying a distinct protocol.

     For example to read a sequence of files split1.mpeg, split2.mpeg,
     split3.mpeg with ffplay use the command:

	     ffplay concat:split1.mpeg\|split2.mpeg\|split3.mpeg

     Note that you may need to escape the character "|" which is special for
     many shells.

   concatf
     Physical concatenation protocol using a line break delimited list of re-
     sources.

     Read and seek from many resources in sequence as if they were a unique re-
     source.

     A URL accepted by this protocol has the syntax:

	     concatf:<URL>

     where URL is the url containing a line break delimited list of resources to
     be concatenated, each one possibly specifying a distinct protocol. Special
     characters must be escaped with backslash or single quotes. See the "Quot-
     ing and escaping" section in the ffmpeg-utils(1) manual.

     For example to read a sequence of files split1.mpeg, split2.mpeg,
     split3.mpeg listed in separate lines within a file split.txt with ffplay
     use the command:

	     ffplay concatf:split.txt

     Where split.txt contains the lines:

	     split1.mpeg
	     split2.mpeg
	     split3.mpeg

   crypto
     AES-encrypted stream reading protocol.

     The accepted options are:

     key Set the AES decryption key binary block from given hexadecimal repre-
	 sentation.

     iv  Set the AES decryption initialization vector binary block from given
	 hexadecimal representation.

     Accepted URL formats:

	     crypto:<URL>
	     crypto+<URL>

   data
     Data in-line in the URI. See
     <http://en.wikipedia.org/wiki/Data_URI_scheme>.

     For example, to convert a GIF file given inline with ffmpeg:

	     ffmpeg -i "data:image/gif;base64,R0lGODdhCAAIAMIEAAAAAAAA//8AAP//AP///////////////ywAAAAACAAIAAADF0gEDLojDgdGiJdJqUX02iB4E8Q9jUMkADs=" smiley.png

   fd
     File descriptor access protocol.

     The accepted syntax is:

	     fd: -fd <file_descriptor>

     If fd is not specified, by default the stdout file descriptor will be used
     for writing, stdin for reading. Unlike the pipe protocol, fd protocol has
     seek support if it corresponding to a regular file. fd protocol doesn't
     support pass file descriptor via URL for security.

     This protocol accepts the following options:

     blocksize
	 Set I/O operation maximum block size, in bytes. Default value is
	 "INT_MAX", which results in not limiting the requested block size.
	 Setting this value reasonably low improves user termination request re-
	 action time, which is valuable if data transmission is slow.

     fd  Set file descriptor.

   file
     File access protocol.

     Read from or write to a file.

     A file URL can have the form:

	     file:<filename>

     where filename is the path of the file to read.

     An URL that does not have a protocol prefix will be assumed to be a file
     URL. Depending on the build, an URL that looks like a Windows path with the
     drive letter at the beginning will also be assumed to be a file URL (usu-
     ally not the case in builds for unix-like systems).

     For example to read from a file input.mpeg with ffmpeg use the command:

	     ffmpeg -i file:input.mpeg output.mpeg

     This protocol accepts the following options:

     truncate
	 Truncate existing files on write, if set to 1. A value of 0 prevents
	 truncating. Default value is 1.

     blocksize
	 Set I/O operation maximum block size, in bytes. Default value is
	 "INT_MAX", which results in not limiting the requested block size.
	 Setting this value reasonably low improves user termination request re-
	 action time, which is valuable for files on slow medium.

     follow
	 If set to 1, the protocol will retry reading at the end of the file,
	 allowing reading files that still are being written. In order for this
	 to terminate, you either need to use the rw_timeout option, or use the
	 interrupt callback (for API users).

     seekable
	 Controls if seekability is advertised on the file. 0 means non-seek-
	 able, -1 means auto (seekable for normal files, non-seekable for named
	 pipes).

	 Many demuxers handle seekable and non-seekable resources differently,
	 overriding this might speed up opening certain files at the cost of
	 losing some features (e.g. accurate seeking).

     pkt_size
	 Set the maximum packet size used for file I/O. A smaller value may re-
	 duce memory usage. A higher value may increase throughput especially
	 with networked filesystems.

	 For reading, if explicitly set, it overrides the default internal
	 buffer size (32 KB) and limits the maximum amount of data read per op-
	 eration.

	 For writing, this sets the size of each write operation. The default is
	 256 KB for regular files, 32 KB otherwise.

   ftp
     FTP (File Transfer Protocol).

     Read from or write to remote resources using FTP protocol.

     Following syntax is required.

	     ftp://[user[:password]@]server[:port]/path/to/remote/resource.mpeg

     This protocol accepts the following options.

     timeout
	 Set timeout in microseconds of socket I/O operations used by the under-
	 lying low level operation. By default it is set to -1, which means that
	 the timeout is not specified.

     ftp-user
	 Set a user to be used for authenticating to the FTP server. This is
	 overridden by the user in the FTP URL.

     ftp-password
	 Set a password to be used for authenticating to the FTP server. This is
	 overridden by the password in the FTP URL, or by ftp-anonymous-password
	 if no user is set.

     ftp-anonymous-password
	 Password used when login as anonymous user. Typically an e-mail address
	 should be used.

     ftp-write-seekable
	 Control seekability of connection during encoding. If set to 1 the re-
	 source is supposed to be seekable, if set to 0 it is assumed not to be
	 seekable. Default value is 0.

     NOTE: Protocol can be used as output, but it is recommended to not do it,
     unless special care is taken (tests, customized server configuration etc.).
     Different FTP servers behave in different way during seek operation. ff*
     tools may produce incomplete content due to server limitations.

   gopher
     Gopher protocol.

   gophers
     Gophers protocol.

     The Gopher protocol with TLS encapsulation.

   http
     HTTP (Hyper Text Transfer Protocol).

     This protocol accepts the following options:

     seekable
	 Control seekability of connection. If set to 1 the resource is supposed
	 to be seekable, if set to 0 it is assumed not to be seekable, if set to
	 -1 it will try to autodetect if it is seekable. Default value is -1.

     chunked_post
	 If set to 1 use chunked Transfer-Encoding for posts, default is 1.

     http_proxy
	 set HTTP proxy to tunnel through e.g. http://example.com:1234

     headers
	 Set custom HTTP headers, can override built in default headers. The
	 value must be a string encoding the headers.

     content_type
	 Set a specific content type for the POST messages or for listen mode.

     user_agent
	 Override the User-Agent header. If not specified the protocol will use
	 a string describing the libavformat build. ("Lavf/<version>")

     referer
	 Set the Referer header. Include 'Referer: URL' header in HTTP request.

     multiple_requests
	 Use persistent connections if set to 1, default is 0.

     request_size
	 Limit the size of requests made. This is useful for some pathological
	 servers that throttle unbounded range requests, as well as when expect-
	 ing to seek frequently. Disabled (set to 0) by default.

	 Note that if enabling this option, it's strongly recommended to also
	 enable the multiple_requests option, as well as setting short_seek_size
	 to the same value or higher. Doing so allows FFmpeg to reuse a single
	 HTTP connection wherever possible.

     initial_request_size
	 Limit the size of initial requests. Similar to "request_size", but only
	 used during initial format parsing. Useful for formats like MXF or MOV
	 that require frequent seeks during header parsing. Lasts until the de-
	 muxer makes a read request larger than this size (without a seek in be-
	 tween), after which the implementation will continue using requests as
	 usual. Disabled (set to 0) by default.

	 Note that if enabling this option, it's strongly recommended to also
	 enable the multiple_requests option, as well as setting short_seek_size
	 to the same value or higher.

     post_data
	 Set custom HTTP post data.

     mime_type
	 Export the MIME type.

     http_version
	 Exports the HTTP response version number. Usually "1.0" or "1.1".

     cookies
	 Set the cookies to be sent in future requests. The format of each
	 cookie is the same as the value of a Set-Cookie HTTP response field.
	 Multiple cookies can be delimited by a newline character.

     icy If set to 1 request ICY (SHOUTcast) metadata from the server. If the
	 server supports this, the metadata has to be retrieved by the applica-
	 tion by reading the icy_metadata_headers and icy_metadata_packet op-
	 tions.  The default is 1.

     icy_metadata_headers
	 If the server supports ICY metadata, this contains the ICY-specific
	 HTTP reply headers, separated by newline characters.

     icy_metadata_packet
	 If the server supports ICY metadata, and icy was set to 1, this con-
	 tains the last non-empty metadata packet sent by the server. It should
	 be polled in regular intervals by applications interested in mid-stream
	 metadata updates.

     metadata
	 Set an exported dictionary containing Icecast metadata from the bit-
	 stream, if present.  Only useful with the C API.

     auth_type
	 Set HTTP authentication type. No option for Digest, since this method
	 requires getting nonce parameters from the server first and can't be
	 used straight away like Basic.

	 noneChoose the HTTP authentication type automatically. This is the de-
	     fault.

	 basic
	     Choose the HTTP basic authentication.

	     Basic authentication sends a Base64-encoded string that contains a
	     user name and password for the client. Base64 is not a form of en-
	     cryption and should be considered the same as sending the user name
	     and password in clear text (Base64 is a reversible encoding).  If a
	     resource needs to be protected, strongly consider using an authen-
	     tication scheme other than basic authentication. HTTPS/TLS should
	     be used with basic authentication.  Without these additional secu-
	     rity enhancements, basic authentication should not be used to pro-
	     tect sensitive or valuable information.

     send_expect_100
	 Send an Expect: 100-continue header for POST. If set to 1 it will send,
	 if set to 0 it won't, if set to -1 it will try to send if it is applic-
	 able. Default value is -1.

     location
	 An exported dictionary containing the content location. Only useful
	 with the C API.

     offset
	 Set initial byte offset.

     end_offset
	 Try to limit the request to bytes preceding this offset.

     method
	 When used as a client option it sets the HTTP method for the request.

	 When used as a server option it sets the HTTP method that is going to
	 be expected from the client(s).  If the expected and the received HTTP
	 method do not match the client will be given a Bad Request response.
	 When unset the HTTP method is not checked for now. This will be re-
	 placed by autodetection in the future.

     reconnect
	 Reconnect automatically when disconnected before EOF is hit.

     reconnect_at_eof
	 If set then eof is treated like an error and causes reconnection, this
	 is useful for live / endless streams.

     reconnect_on_network_error
	 Reconnect automatically in case of TCP/TLS errors during connect.

     reconnect_on_http_error
	 A comma separated list of HTTP status codes to reconnect on. The list
	 can include specific status codes (e.g. '503') or the strings '4xx' /
	 '5xx'.

     reconnect_streamed
	 If set then even streamed/non seekable streams will be reconnected on
	 errors.

     reconnect_delay_max
	 Set the maximum delay in seconds after which to give up reconnecting.

     reconnect_max_retries
	 Set the maximum number of times to retry a connection. Default unset.

     reconnect_delay_total_max
	 Set the maximum total delay in seconds after which to give up recon-
	 necting.

     respect_retry_after
	 If enabled, and a Retry-After header is encountered, its requested re-
	 connection delay will be honored, rather than using exponential back-
	 off. Useful for 429 and 503 errors. Default enabled.

     listen
	 If set to 1 enables experimental HTTP server. This can be used to send
	 data when used as an output option, or read data from a client with
	 HTTP POST when used as an input option.  If set to 2 enables experimen-
	 tal multi-client HTTP server. This is not yet implemented in ffmpeg.c
	 and thus must not be used as a command line option.

		 # Server side (sending):
		 ffmpeg -i somefile.ogg -c copy -listen 1 -f ogg http://<server>:<port>

		 # Client side (receiving):
		 ffmpeg -i http://<server>:<port> -c copy somefile.ogg

		 # Client can also be done with wget:
		 wget http://<server>:<port> -O somefile.ogg

		 # Server side (receiving):
		 ffmpeg -listen 1 -i http://<server>:<port> -c copy somefile.ogg

		 # Client side (sending):
		 ffmpeg -i somefile.ogg -chunked_post 0 -c copy -f ogg http://<server>:<port>

		 # Client can also be done with wget:
		 wget --post-file=somefile.ogg http://<server>:<port>

     resource
	 The resource requested by a client, when the experimental HTTP server
	 is in use.

     reply_code
	 The HTTP code returned to the client, when the experimental HTTP server
	 is in use.

     short_seek_size
	 Set the threshold, in bytes, for when a readahead should be preferred
	 over a seek and new HTTP request. This is useful, for example, to make
	 sure the same connection is used for reading large video packets with
	 small audio packets in between.

     HTTP Cookies

     Some HTTP requests will be denied unless cookie values are passed in with
     the request. The cookies option allows these cookies to be specified. At
     the very least, each cookie must specify a value along with a path and do-
     main.  HTTP requests that match both the domain and path will automatically
     include the cookie value in the HTTP Cookie header field. Multiple cookies
     can be delimited by a newline.

     The required syntax to play a stream specifying a cookie is:

	     ffplay -cookies "nlqptid=nltid=tsn; path=/; domain=somedomain.com;" http://somedomain.com/somestream.m3u8

   Icecast
     Icecast protocol (stream to Icecast servers)

     This protocol accepts the following options:

     ice_genre
	 Set the stream genre.

     ice_name
	 Set the stream name.

     ice_description
	 Set the stream description.

     ice_url
	 Set the stream website URL.

     ice_public
	 Set if the stream should be public.  The default is 0 (not public).

     user_agent
	 Override the User-Agent header. If not specified a string of the form
	 "Lavf/<version>" will be used.

     password
	 Set the Icecast mountpoint password.

     content_type
	 Set the stream content type. This must be set if it is different from
	 audio/mpeg.

     legacy_icecast
	 This enables support for Icecast versions < 2.4.0, that do not support
	 the HTTP PUT method but the SOURCE method.

     tls Establish a TLS (HTTPS) connection to Icecast.

	     icecast://[<username>[:<password>]@]<server>:<port>/<mountpoint>

   ipfs
     InterPlanetary File System (IPFS) protocol support. One can access files
     stored on the IPFS network through so-called gateways. These are http(s)
     endpoints.  This protocol wraps the IPFS native protocols (ipfs:// and
     ipns://) to be sent to such a gateway. Users can (and should) host their
     own node which means this protocol will use one's local gateway to access
     files on the IPFS network.

     This protocol accepts the following options:

     gateway
	 Defines the gateway to use. When not set, the protocol will first try
	 locating the local gateway by looking at $IPFS_GATEWAY, $IPFS_PATH and
	 "$HOME/.ipfs/", in that order.

     One can use this protocol in 2 ways. Using IPFS:

	     ffplay ipfs://<hash>

     Or the IPNS protocol (IPNS is mutable IPFS):

	     ffplay ipns://<hash>

   mmst
     MMS (Microsoft Media Server) protocol over TCP.

   mmsh
     MMS (Microsoft Media Server) protocol over HTTP.

     The required syntax is:

	     mmsh://<server>[:<port>][/<app>][/<playpath>]

   md5
     MD5 output protocol.

     Computes the MD5 hash of the data to be written, and on close writes this
     to the designated output or stdout if none is specified. It can be used to
     test muxers without writing an actual file.

     Some examples follow.

	     # Write the MD5 hash of the encoded AVI file to the file output.avi.md5.
	     ffmpeg -i input.flv -f avi -y md5:output.avi.md5

	     # Write the MD5 hash of the encoded AVI file to stdout.
	     ffmpeg -i input.flv -f avi -y md5:

     Note that some formats (typically MOV) require the output protocol to be
     seekable, so they will fail with the MD5 output protocol.

   pipe
     UNIX pipe access protocol.

     Read and write from UNIX pipes.

     The accepted syntax is:

	     pipe:[<number>]

     If fd isn't specified, number is the number corresponding to the file de-
     scriptor of the pipe (e.g. 0 for stdin, 1 for stdout, 2 for stderr).  If
     number is not specified, by default the stdout file descriptor will be used
     for writing, stdin for reading.

     For example to read from stdin with ffmpeg:

	     cat test.wav | ffmpeg -i pipe:0
	     # ...this is the same as...
	     cat test.wav | ffmpeg -i pipe:

     For writing to stdout with ffmpeg:

	     ffmpeg -i test.wav -f avi pipe:1 | cat > test.avi
	     # ...this is the same as...
	     ffmpeg -i test.wav -f avi pipe: | cat > test.avi

     This protocol accepts the following options:

     blocksize
	 Set I/O operation maximum block size, in bytes. Default value is
	 "INT_MAX", which results in not limiting the requested block size.
	 Setting this value reasonably low improves user termination request re-
	 action time, which is valuable if data transmission is slow.

     fd  Set file descriptor.

     Note that some formats (typically MOV), require the output protocol to be
     seekable, so they will fail with the pipe output protocol.

   prompeg
     Pro-MPEG Code of Practice #3 Release 2 FEC protocol.

     The Pro-MPEG CoP#3 FEC is a 2D parity-check forward error correction mecha-
     nism for MPEG-2 Transport Streams sent over RTP.

     This protocol must be used in conjunction with the "rtp_mpegts" muxer and
     the "rtp" protocol.

     The required syntax is:

	     -f rtp_mpegts -fec prompeg=<option>=<val>... rtp://<hostname>:<port>

     The destination UDP ports are "port + 2" for the column FEC stream and
     "port + 4" for the row FEC stream.

     This protocol accepts the following options:

     l=n The number of columns (4-20, LxD <= 100)

     d=n The number of rows (4-20, LxD <= 100)

     Example usage:

	     -f rtp_mpegts -fec prompeg=l=8:d=4 rtp://<hostname>:<port>

   rist
     Reliable Internet Streaming Transport protocol

     The accepted options are:

     rist_profile
	 Supported values:

	 simple
	 mainThis one is default.

	 advanced

     buffer_size
	 Set internal RIST buffer size in milliseconds for retransmission of
	 data.	Default value is 0 which means the librist default (1 sec). Max-
	 imum value is 30 seconds.

     fifo_size
	 Size of the librist receiver output fifo in number of packets. This
	 must be a power of 2.	Defaults to 8192 (vs the librist default of
	 1024).

     overrun_nonfatal=1|0
	 Survive in case of librist fifo buffer overrun. Default value is 0.

     pkt_size
	 Set maximum packet size for sending data. 1316 by default.

     log_level
	 Set loglevel for RIST logging messages. You only need to set this if
	 you explicitly want to enable debug level messages or packet loss simu-
	 lation, otherwise the regular loglevel is respected.

     secret
	 Set override of encryption secret, by default is unset.

     encryption
	 Set encryption type, by default is disabled.  Acceptable values are 128
	 and 256.

   rtmp
     Real-Time Messaging Protocol.

     The Real-Time Messaging Protocol (RTMP) is used for streaming multimedia
     content across a TCP/IP network.

     The required syntax is:

	     rtmp://[<username>:<password>@]<server>[:<port>][/<app>][/<instance>][/<playpath>]

     The accepted parameters are:

     username
	 An optional username (mostly for publishing).

     password
	 An optional password (mostly for publishing).

     server
	 The address of the RTMP server.

     portThe number of the TCP port to use (by default is 1935).

     app It is the name of the application to access. It usually corresponds to
	 the path where the application is installed on the RTMP server (e.g.
	 /ondemand/, /flash/live/, etc.). You can override the value parsed from
	 the URI through the "rtmp_app" option, too.

     playpath
	 It is the path or name of the resource to play with reference to the
	 application specified in app, may be prefixed by "mp4:". You can over-
	 ride the value parsed from the URI through the "rtmp_playpath" option,
	 too.

     listen
	 Act as a server, listening for an incoming connection.

     timeout
	 Maximum time to wait for the incoming connection. Implies listen.

     Additionally, the following parameters can be set via command line options
     (or in code via "AVOption"s):

     rtmp_app
	 Name of application to connect on the RTMP server. This option over-
	 rides the parameter specified in the URI.

     rtmp_buffer
	 Set the client buffer time in milliseconds. The default is 3000.

     rtmp_conn
	 Extra arbitrary AMF connection parameters, parsed from a string, e.g.
	 like "B:1 S:authMe O:1 NN:code:1.23 NS:flag:ok O:0".  Each value is
	 prefixed by a single character denoting the type, B for Boolean, N for
	 number, S for string, O for object, or Z for null, followed by a colon.
	 For Booleans the data must be either 0 or 1 for FALSE or TRUE, respec-
	 tively.  Likewise for Objects the data must be 0 or 1 to end or begin
	 an object, respectively. Data items in subobjects may be named, by pre-
	 fixing the type with 'N' and specifying the name before the value (i.e.
	 "NB:myFlag:1"). This option may be used multiple times to construct ar-
	 bitrary AMF sequences.

     rtmp_enhanced_codecs
	 Specify the list of codecs the client advertises to support in an en-
	 hanced RTMP stream. This option should be set to a comma separated list
	 of fourcc values, like "hvc1,av01,vp09" for multiple codecs or "hvc1"
	 for only one codec. The specified list will be presented in the "four-
	 CcLive" property of the Connect Command Message.

     rtmp_flashver
	 Version of the Flash plugin used to run the SWF player. The default is
	 LNX 9,0,124,2. (When publishing, the default is FMLE/3.0 (compatible;
	 <libavformat version>).)

     rtmp_flush_interval
	 Number of packets flushed in the same request (RTMPT only). The default
	 is 10.

     rtmp_live
	 Specify that the media is a live stream. No resuming or seeking in live
	 streams is possible. The default value is "any", which means the sub-
	 scriber first tries to play the live stream specified in the playpath.
	 If a live stream of that name is not found, it plays the recorded
	 stream. The other possible values are "live" and "recorded".

     rtmp_pageurl
	 URL of the web page in which the media was embedded. By default no
	 value will be sent.

     rtmp_playpath
	 Stream identifier to play or to publish. This option overrides the pa-
	 rameter specified in the URI.

     rtmp_subscribe
	 Name of live stream to subscribe to. By default no value will be sent.
	 It is only sent if the option is specified or if rtmp_live is set to
	 live.

     rtmp_swfhash
	 SHA256 hash of the decompressed SWF file (32 bytes).

     rtmp_swfsize
	 Size of the decompressed SWF file, required for SWFVerification.

     rtmp_swfurl
	 URL of the SWF player for the media. By default no value will be sent.

     rtmp_swfverify
	 URL to player swf file, compute hash/size automatically.

     rtmp_tcurl
	 URL of the target stream. Defaults to proto://host[:port]/app.

     tcp_nodelay=1|0
	 Set TCP_NODELAY to disable Nagle's algorithm. Default value is 0.

	 Remark: Writing to the socket is currently not optimized to minimize
	 system calls and reduces the efficiency / effect of TCP_NODELAY.

     tcp_keepalive=1|0
	 Enable the TCP keepalive mechanism to detect dead peers and help main-
	 tain long-lived idle connections. Default value is 0.

	 Only the basic keepalive option (SO_KEEPALIVE) can be enabled or dis-
	 abled. Platform-specific tuning parameters such as TCP_KEEPIDLE,
	 TCP_KEEPINTVL, or TCP_KEEPCNT are not configurable and will use the op-
	 erating system's default values.

     For example to read with ffplay a multimedia resource named "sample" from
     the application "vod" from an RTMP server "myserver":

	     ffplay rtmp://myserver/vod/sample

     To publish to a password protected server, passing the playpath and app
     names separately:

	     ffmpeg -re -i <input> -f flv -rtmp_playpath some/long/path -rtmp_app long/app/name rtmp://username:password@myserver/

   rtmpe
     Encrypted Real-Time Messaging Protocol.

     The Encrypted Real-Time Messaging Protocol (RTMPE) is used for streaming
     multimedia content within standard cryptographic primitives, consisting of
     Diffie-Hellman key exchange and HMACSHA256, generating a pair of RC4 keys.

   rtmps
     Real-Time Messaging Protocol over a secure SSL connection.

     The Real-Time Messaging Protocol (RTMPS) is used for streaming multimedia
     content across an encrypted connection.

   rtmpt
     Real-Time Messaging Protocol tunneled through HTTP.

     The Real-Time Messaging Protocol tunneled through HTTP (RTMPT) is used for
     streaming multimedia content within HTTP requests to traverse firewalls.

   rtmpte
     Encrypted Real-Time Messaging Protocol tunneled through HTTP.

     The Encrypted Real-Time Messaging Protocol tunneled through HTTP (RTMPTE)
     is used for streaming multimedia content within HTTP requests to traverse
     firewalls.

   rtmpts
     Real-Time Messaging Protocol tunneled through HTTPS.

     The Real-Time Messaging Protocol tunneled through HTTPS (RTMPTS) is used
     for streaming multimedia content within HTTPS requests to traverse fire-
     walls.

   libsmbclient
     libsmbclient permits one to manipulate CIFS/SMB network resources.

     Following syntax is required.

	     smb://[[domain:]user[:password@]]server[/share[/path[/file]]]

     This protocol accepts the following options.

     timeout
	 Set timeout in milliseconds of socket I/O operations used by the under-
	 lying low level operation. By default it is set to -1, which means that
	 the timeout is not specified.

     truncate
	 Truncate existing files on write, if set to 1. A value of 0 prevents
	 truncating. Default value is 1.

     workgroup
	 Set the workgroup used for making connections. By default workgroup is
	 not specified.

     For more information see: <http://www.samba.org/>.

   libssh
     Secure File Transfer Protocol via libssh

     Read from or write to remote resources using SFTP protocol.

     Following syntax is required.

	     sftp://[user[:password]@]server[:port]/path/to/remote/resource.mpeg

     This protocol accepts the following options.

     timeout
	 Set timeout of socket I/O operations used by the underlying low level
	 operation. By default it is set to -1, which means that the timeout is
	 not specified.

     truncate
	 Truncate existing files on write, if set to 1. A value of 0 prevents
	 truncating. Default value is 1.

     private_key
	 Specify the path of the file containing private key to use during au-
	 thorization.  By default libssh searches for keys in the ~/.ssh/ direc-
	 tory.

     Example: Play a file stored on remote server.

	     ffplay sftp://user:password@server_address:22/home/user/resource.mpeg

   librtmp rtmp, rtmpe, rtmps, rtmpt, rtmpte
     Real-Time Messaging Protocol and its variants supported through librtmp.

     Requires the presence of the librtmp headers and library during configura-
     tion. You need to explicitly configure the build with "--enable-librtmp".
     If enabled this will replace the native RTMP protocol.

     This protocol provides most client functions and a few server functions
     needed to support RTMP, RTMP tunneled in HTTP (RTMPT), encrypted RTMP
     (RTMPE), RTMP over SSL/TLS (RTMPS) and tunneled variants of these encrypted
     types (RTMPTE, RTMPTS).

     The required syntax is:

	     <rtmp_proto>://<server>[:<port>][/<app>][/<playpath>] <options>

     where rtmp_proto is one of the strings "rtmp", "rtmpt", "rtmpe", "rtmps",
     "rtmpte", "rtmpts" corresponding to each RTMP variant, and server, port,
     app and playpath have the same meaning as specified for the RTMP native
     protocol.	options contains a list of space-separated options of the form
     key=val.

     See the librtmp manual page (man 3 librtmp) for more information.

     For example, to stream a file in real-time to an RTMP server using ffmpeg:

	     ffmpeg -re -i myfile -f flv rtmp://myserver/live/mystream

     To play the same stream using ffplay:

	     ffplay "rtmp://myserver/live/mystream live=1"

   rtp
     Real-time Transport Protocol.

     The required syntax for an RTP URL is:

	     rtp://<hostname>[:<port>][?<options>]

     port specifies the RTP port to use.

     options contains a list of &-separated options of the form key=val. Stan-
     dard percent-encoding (and using the plus sign for space) can be used to
     escape keys and values.

     Options can also can be specified via command line options (or in code via
     "AVOption"s).

     The list of supported options follows.

     ttl=n
	 Set the TTL (Time-To-Live) value (for multicast only).

     rtcpport=n
	 Set the remote RTCP port to n.

     localport, local_rtpport, localrtpport=n
	 Set the local RTP port to n.

	 Using the localport option name is deprecated and should not be used.

     local_rtcpport, localrtcpport=n'
	 Set the local RTCP port to n.

     pkt_size=n
	 Set max packet size (in bytes) to n.

     buffer_size=size
	 Set the maximum UDP socket buffer size in bytes.

     connect=0|1
	 Do a connect() on the UDP socket (if set to 1) or not (if set to 0).

     sources=ip[,ip]
	 List allowed source IP addresses.

     block=ip[,ip]
	 List disallowed (blocked) source IP addresses.

     write_to_source=0|1
	 Send packets to the source address of the latest received packet (if
	 set to 1) or to a default remote address (if set to 0).

     localaddr=addr
	 Local IP address of a network interface used for sending packets or
	 joining multicast groups.

     timeout=n
	 Set timeout (in microseconds) of socket I/O operations to n.

     Important notes:

     1.  If rtcpport is not set the RTCP port will be set to the RTP port value
	 plus 1.

     2.  If localrtpport (the local RTP port) is not set any available port will
	 be used for the local RTP and RTCP ports.

     3.  If localrtcpport (the local RTCP port) is not set it will be set to the
	 local RTP port value plus 1.

   rtsp
     Real-Time Streaming Protocol.

     RTSP is not technically a protocol handler in libavformat, it is a demuxer
     and muxer. The demuxer supports both normal RTSP (with data transferred
     over RTP; this is used by e.g. Apple and Microsoft) and Real-RTSP (with
     data transferred over RDT).

     The muxer can be used to send a stream using RTSP ANNOUNCE to a server sup-
     porting it (currently Darwin Streaming Server and Mischa Spiegelmock's
     <https://github.com/revmischa/rtsp-server>).

     The required syntax for a RTSP url is:

	     rtsp://<hostname>[:<port>]/<path>

     Options can be set on the ffmpeg/ffplay command line, or set in code via
     "AVOption"s or in "avformat_open_input".

     Muxer

     The following options are supported.

     rtsp_transport
	 Set RTSP transport protocols.

	 It accepts the following values:

	 udp Use UDP as lower transport protocol.

	 tcp Use TCP (interleaving within the RTSP control channel) as lower
	     transport protocol.

	 Default value is 0.

     rtsp_flags
	 Set RTSP flags.

	 The following values are accepted:

	 latmUse MP4A-LATM packetization instead of MPEG4-GENERIC for AAC.

	 rfc2190
	     Use RFC 2190 packetization instead of RFC 4629 for H.263.

	 skip_rtcp
	     Don't send RTCP sender reports.

	 h264_mode0
	     Use mode 0 for H.264 in RTP.

	 send_bye
	     Send RTCP BYE packets when finishing.

	 Default value is 0.

     min_port
	 Set minimum local UDP port. Default value is 5000.

     max_port
	 Set maximum local UDP port. Default value is 65000.

     buffer_size
	 Set the maximum socket buffer size in bytes.

     pkt_size
	 Set max send packet size (in bytes). Default value is 1472.

     Demuxer

     The following options are supported.

     initial_pause
	 Do not start playing the stream immediately if set to 1. Default value
	 is 0.

     rtsp_transport
	 Set RTSP transport protocols.

	 It accepts the following values:

	 udp Use UDP as lower transport protocol.

	 tcp Use TCP (interleaving within the RTSP control channel) as lower
	     transport protocol.

	 udp_multicast
	     Use UDP multicast as lower transport protocol.

	 httpUse HTTP tunneling as lower transport protocol, which is useful for
	     passing proxies.

	 https
	     Use HTTPs tunneling as lower transport protocol, which is useful
	     for passing proxies and widely used for security consideration.

	 Multiple lower transport protocols may be specified, in that case they
	 are tried one at a time (if the setup of one fails, the next one is
	 tried).  For the muxer, only the tcp and udp options are supported.

     rtsp_flags
	 Set RTSP flags.

	 The following values are accepted:

	 filter_src
	     Accept packets only from negotiated peer address and port.

	 listen
	     Act as a server, listening for an incoming connection.

	 prefer_tcp
	     Try TCP for RTP transport first, if TCP is available as RTSP RTP
	     transport.

	 satip_raw
	     Export raw MPEG-TS stream instead of demuxing. The flag will simply
	     write out the raw stream, with the original PAT/PMT/PIDs intact.

	 Default value is none.

     allowed_media_types
	 Set media types to accept from the server.

	 The following flags are accepted:

	 video
	 audio
	 data
	 subtitle

	 By default it accepts all media types.

     min_port
	 Set minimum local UDP port. Default value is 5000.

     max_port
	 Set maximum local UDP port. Default value is 65000.

     listen_timeout
	 Set maximum timeout (in seconds) to establish an initial connection.
	 Setting listen_timeout > 0 sets rtsp_flags to listen. Default is -1
	 which means an infinite timeout when listen mode is set.

     reorder_queue_size
	 Set number of packets to buffer for handling of reordered packets.

     timeout
	 Set socket TCP I/O timeout in microseconds.

     user_agent
	 Override User-Agent header. If not specified, it defaults to the libav-
	 format identifier string.

     buffer_size
	 Set the maximum socket buffer size in bytes.

     When receiving data over UDP, the demuxer tries to reorder received packets
     (since they may arrive out of order, or packets may get lost totally). This
     can be disabled by setting the maximum demuxing delay to zero (via the
     "max_delay" field of AVFormatContext).

     When watching multi-bitrate Real-RTSP streams with ffplay, the streams to
     display can be chosen with "-vst" n and "-ast" n for video and audio re-
     spectively, and can be switched on the fly by pressing "v" and "a".

     Examples

     The following examples all make use of the ffplay and ffmpeg tools.

     *	 Watch a stream over UDP, with a max reordering delay of 0.5 seconds:

		 ffplay -max_delay 500000 -rtsp_transport udp rtsp://server/video.mp4

     *	 Watch a stream tunneled over HTTP:

		 ffplay -rtsp_transport http rtsp://server/video.mp4

     *	 Send a stream in realtime to a RTSP server, for others to watch:

		 ffmpeg -re -i <input> -f rtsp -muxdelay 0.1 rtsp://server/live.sdp

     *	 Receive a stream in realtime:

		 ffmpeg -rtsp_flags listen -i rtsp://ownaddress/live.sdp <output>

   sap
     Session Announcement Protocol (RFC 2974). This is not technically a proto-
     col handler in libavformat, it is a muxer and demuxer.  It is used for sig-
     nalling of RTP streams, by announcing the SDP for the streams regularly on
     a separate port.

     Muxer

     The syntax for a SAP url given to the muxer is:

	     sap://<destination>[:<port>][?<options>]

     The RTP packets are sent to destination on port port, or to port 5004 if no
     port is specified.  options is a "&"-separated list. The following options
     are supported:

     announce_addr=address
	 Specify the destination IP address for sending the announcements to.
	 If omitted, the announcements are sent to the commonly used SAP an-
	 nouncement multicast address 224.2.127.254 (sap.mcast.net), or
	 ff0e::2:7ffe if destination is an IPv6 address.

     announce_port=port
	 Specify the port to send the announcements on, defaults to 9875 if not
	 specified.

     ttl=ttl
	 Specify the time to live value for the announcements and RTP packets,
	 defaults to 255.

     same_port=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.  The RTP stack in libav-
	 format for receiving requires all streams to be sent on unique ports.

     Example command lines follow.

     To broadcast a stream on the local subnet, for watching in VLC:

	     ffmpeg -re -i <input> -f sap sap://224.0.0.255?same_port=1

     Similarly, for watching in ffplay:

	     ffmpeg -re -i <input> -f sap sap://224.0.0.255

     And for watching in ffplay, over IPv6:

	     ffmpeg -re -i <input> -f sap sap://[ff0e::1:2:3:4]

     Demuxer

     The syntax for a SAP url given to the demuxer is:

	     sap://[<address>][:<port>]

     address is the multicast address to listen for announcements on, if omit-
     ted, the default 224.2.127.254 (sap.mcast.net) is used. 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 ad-
     dress:

	     ffplay sap://

     To play back the first stream announced on one the default IPv6 SAP multi-
     cast address:

	     ffplay sap://[ff0e::2:7ffe]

   sctp
     Stream Control Transmission Protocol.

     The accepted URL syntax is:

	     sctp://<host>:<port>[?<options>]

     options contains a list of &-separated options of the form key=val. Stan-
     dard percent-encoding (and using the plus sign for space) can be used to
     escape keys and values.

     Options can also can be specified via command line options (or in code via
     "AVOption"s).

     The list of supported options follows.

     listen
	 If set to any value, listen for an incoming connection. Outgoing con-
	 nection is done by default.

     max_streams
	 Set the maximum number of streams. By default no limit is set.

   srt
     Haivision Secure Reliable Transport Protocol via libsrt.

     The supported syntax for a SRT URL is:

	     srt://<hostname>:<port>[?<options>]

     options contains a list of &-separated options of the form key=val. Stan-
     dard percent-encoding (and using the plus sign for space) can be used to
     escape keys and values.

     Options can also can be specified via command line options (or in code via
     "AVOption"s).

     The list of supported options follows.

     connect_timeout=milliseconds
	 Connection timeout; SRT cannot connect for RTT > 1500 msec (2 handshake
	 exchanges) with the default connect timeout of 3 seconds. This option
	 applies to the caller and rendezvous connection modes. The connect
	 timeout is 10 times the value set for the rendezvous mode (which can be
	 used as a workaround for this connection problem with earlier ver-
	 sions).

     ffs=bytes
	 Flight Flag Size (Window Size), in bytes. FFS is actually an internal
	 parameter and you should set it to not less than recv_buffer_size and
	 mss. The default value is relatively large, therefore unless you set a
	 very large receiver buffer, you do not need to change this option. De-
	 fault value is 25600.

     inputbw=bytes/seconds
	 Sender nominal input rate, in bytes per seconds. Used along with
	 oheadbw, when maxbw is set to relative (0), to calculate maximum send-
	 ing rate when recovery packets are sent along with the main media
	 stream: inputbw * (100 + oheadbw) / 100 if inputbw is not set while
	 maxbw is set to relative (0), the actual input rate is evaluated inside
	 the library. Default value is 0.

     iptos=tos
	 IP Type of Service. Applies to sender only. Default value is 0xB8.

     ipttl=ttl
	 IP Time To Live. Applies to sender only. Default value is 64.

     latency=microseconds
	 Timestamp-based Packet Delivery Delay.  Used to absorb bursts of missed
	 packet retransmissions.  This flag sets both rcvlatency and peerlatency
	 to the same value. Note that prior to version 1.3.0 this is the only
	 flag to set the latency, however this is effectively equivalent to set-
	 ting peerlatency, when side is sender and rcvlatency when side is re-
	 ceiver, and the bidirectional stream sending is not supported.

     listen_timeout=microseconds
	 Set socket listen timeout.

     maxbw=bytes/seconds
	 Maximum sending bandwidth, in bytes per seconds.  -1 infinite (CSRTCC
	 limit is 30mbps) 0 relative to input rate (see inputbw) >0 absolute
	 limit value Default value is 0 (relative)

     mode=caller|listener|rendezvous
	 Connection mode.  caller opens client connection.  listener starts
	 server to listen for incoming connections.  rendezvous use Rendez-Vous
	 connection mode.  Default value is caller.

     mss=bytes
	 Maximum Segment Size, in bytes. Used for buffer allocation and rate
	 calculation using a packet counter assuming fully filled packets. The
	 smallest MSS between the peers is used. This is 1500 by default in the
	 overall internet.  This is the maximum size of the UDP packet and can
	 be only decreased, unless you have some unusual dedicated network set-
	 tings. Default value is 1500.

     nakreport=1|0
	 If set to 1, Receiver will send `UMSG_LOSSREPORT` messages periodically
	 until a lost packet is retransmitted or intentionally dropped. Default
	 value is 1.

     oheadbw=percents
	 Recovery bandwidth overhead above input rate, in percents.  See in-
	 putbw. Default value is 25%.

     passphrase=string
	 HaiCrypt Encryption/Decryption Passphrase string, length from 10 to 79
	 characters. The passphrase is the shared secret between the sender and
	 the receiver. It is used to generate the Key Encrypting Key using
	 PBKDF2 (Password-Based Key Derivation Function). It is used only if
	 pbkeylen is non-zero. It is used on the receiver only if the received
	 data is encrypted.  The configured passphrase cannot be recovered
	 (write-only).

     enforced_encryption=1|0
	 If true, both connection parties must have the same password set (in-
	 cluding empty, that is, with no encryption). If the password doesn't
	 match or only one side is unencrypted, the connection is rejected. De-
	 fault is true.

     kmrefreshrate=packets
	 The number of packets to be transmitted after which the encryption key
	 is switched to a new key. Default is -1.  -1 means auto (0x1000000 in
	 srt library). The range for this option is integers in the 0 -
	 "INT_MAX".

     kmpreannounce=packets
	 The interval between when a new encryption key is sent and when
	 switchover occurs. This value also applies to the subsequent interval
	 between when switchover occurs and when the old encryption key is de-
	 commissioned. Default is -1.  -1 means auto (0x1000 in srt library).
	 The range for this option is integers in the 0 - "INT_MAX".

     snddropdelay=microseconds
	 The sender's extra delay before dropping packets. This delay is added
	 to the default drop delay time interval value.

	 Special value -1: Do not drop packets on the sender at all.

     payload_size=bytes
	 Sets the maximum declared size of a packet transferred during the sin-
	 gle call to the sending function in Live mode. Use 0 if this value
	 isn't used (which is default in file mode).  Default is -1 (automatic),
	 which typically means MPEG-TS; if you are going to use SRT to send any
	 different kind of payload, such as, for example, wrapping a live stream
	 in very small frames, then you can use a bigger maximum frame size,
	 though not greater than 1456 bytes.

     pkt_size=bytes
	 Alias for payload_size.

     peerlatency=microseconds
	 The latency value (as described in rcvlatency) that is set by the
	 sender side as a minimum value for the receiver.

     pbkeylen=bytes
	 Sender encryption key length, in bytes.  Only can be set to 0, 16, 24
	 and 32.  Enable sender encryption if not 0.  Not required on receiver
	 (set to 0), key size obtained from sender in HaiCrypt handshake.  De-
	 fault value is 0.

     rcvlatency=microseconds
	 The time that should elapse since the moment when the packet was sent
	 and the moment when it's delivered to the receiver application in the
	 receiving function.  This time should be a buffer time large enough to
	 cover the time spent for sending, unexpectedly extended RTT time, and
	 the time needed to retransmit the lost UDP packet. The effective la-
	 tency value will be the maximum of this options' value and the value of
	 peerlatency set by the peer side. Before version 1.3.0 this option is
	 only available as latency.

     recv_buffer_size=bytes
	 Set UDP receive buffer size, expressed in bytes.

     send_buffer_size=bytes
	 Set UDP send buffer size, expressed in bytes.

     timeout=microseconds
	 Set raise error timeouts for read, write and connect operations. Note
	 that the SRT library has internal timeouts which can be controlled sep-
	 arately, the value set here is only a cap on those.

     tlpktdrop=1|0
	 Too-late Packet Drop. When enabled on receiver, it skips missing pack-
	 ets that have not been delivered in time and delivers the following
	 packets to the application when their time-to-play has come. It also
	 sends a fake ACK to the sender. When enabled on sender and enabled on
	 the receiving peer, the sender drops the older packets that have no
	 chance of being delivered in time. It was automatically enabled in the
	 sender if the receiver supports it.

     sndbuf=bytes
	 Set send buffer size, expressed in bytes.

     rcvbuf=bytes
	 Set receive buffer size, expressed in bytes.

	 Receive buffer must not be greater than ffs.

     lossmaxttl=packets
	 The value up to which the Reorder Tolerance may grow. When Reorder Tol-
	 erance is > 0, then packet loss report is delayed until that number of
	 packets come in. Reorder Tolerance increases every time a "belated"
	 packet has come, but it wasn't due to retransmission (that is, when UDP
	 packets tend to come out of order), with the difference between the
	 latest sequence and this packet's sequence, and not more than the value
	 of this option. By default it's 0, which means that this mechanism is
	 turned off, and the loss report is always sent immediately upon experi-
	 encing a "gap" in sequences.

     minversion
	 The minimum SRT version that is required from the peer. A connection to
	 a peer that does not satisfy the minimum version requirement will be
	 rejected.

	 The version format in hex is 0xXXYYZZ for x.y.z in human readable form.

     streamid=string
	 A string limited to 512 characters that can be set on the socket prior
	 to connecting. This stream ID will be able to be retrieved by the lis-
	 tener side from the socket that is returned from srt_accept and was
	 connected by a socket with that set stream ID. SRT does not enforce any
	 special interpretation of the contents of this string.  This option
	 doesnat make sense in Rendezvous connection; the result might be that
	 simply one side will override the value from the other side and itas
	 the matter of luck which one would win

     srt_streamid=string
	 Alias for streamid to avoid conflict with ffmpeg command line option.

     smoother=live|file
	 The type of Smoother used for the transmission for that socket, which
	 is responsible for the transmission and congestion control. The
	 Smoother type must be exactly the same on both connecting parties, oth-
	 erwise the connection is rejected.

     messageapi=1|0
	 When set, this socket uses the Message API, otherwise it uses Buffer
	 API. Note that in live mode (see transtype) thereas only message API
	 available. In File mode you can chose to use one of two modes:

	 Stream API (default, when this option is false). In this mode you may
	 send as many data as you wish with one sending instruction, or even use
	 dedicated functions that read directly from a file. The internal facil-
	 ity will take care of any speed and congestion control. When receiving,
	 you can also receive as many data as desired, the data not extracted
	 will be waiting for the next call. There is no boundary between data
	 portions in the Stream mode.

	 Message API. In this mode your single sending instruction passes ex-
	 actly one piece of data that has boundaries (a message). Contrary to
	 Live mode, this message may span across multiple UDP packets and the
	 only size limitation is that it shall fit as a whole in the sending
	 buffer. The receiver shall use as large buffer as necessary to receive
	 the message, otherwise the message will not be given up. When the mes-
	 sage is not complete (not all packets received or there was a packet
	 loss) it will not be given up.

     transtype=live|file
	 Sets the transmission type for the socket, in particular, setting this
	 option sets multiple other parameters to their default values as re-
	 quired for a particular transmission type.

	 live: Set options as for live transmission. In this mode, you should
	 send by one sending instruction only so many data that fit in one UDP
	 packet, and limited to the value defined first in payload_size (1316 is
	 default in this mode). There is no speed control in this mode, only the
	 bandwidth control, if configured, in order to not exceed the bandwidth
	 with the overhead transmission (retransmitted and control packets).

	 file: Set options as for non-live transmission. See messageapi for fur-
	 ther explanations

     linger=seconds
	 The number of seconds that the socket waits for unsent data when clos-
	 ing.  Default is -1. -1 means auto (off with 0 seconds in live mode, on
	 with 180 seconds in file mode). The range for this option is integers
	 in the 0 - "INT_MAX".

     tsbpd=1|0
	 When true, use Timestamp-based Packet Delivery mode. The default behav-
	 ior depends on the transmission type: enabled in live mode, disabled in
	 file mode.

     For more information see: <https://github.com/Haivision/srt>.

   srtp
     Secure Real-time Transport Protocol.

     The accepted options are:

     srtp_in_suite
     srtp_out_suite
	 Select input and output encoding suites.

	 Supported values:

	 AES_CM_128_HMAC_SHA1_80
	 SRTP_AES128_CM_HMAC_SHA1_80
	 AES_CM_128_HMAC_SHA1_32
	 SRTP_AES128_CM_HMAC_SHA1_32

     srtp_in_params
     srtp_out_params
	 Set input and output encoding parameters, which are expressed by a
	 base64-encoded representation of a binary block. The first 16 bytes of
	 this binary block are used as master key, the following 14 bytes are
	 used as master salt.

   subfile
     Virtually extract a segment of a file or another stream.  The underlying
     stream must be seekable.

     Accepted options:

     start
	 Start offset of the extracted segment, in bytes.

     end End offset of the extracted segment, in bytes.  If set to 0, extract
	 till end of file.

     Examples:

     Extract a chapter from a DVD VOB file (start and end sectors obtained ex-
     ternally and multiplied by 2048):

	     subfile,,start,153391104,end,268142592,,:/media/dvd/VIDEO_TS/VTS_08_1.VOB

     Play an AVI file directly from a TAR archive:

	     subfile,,start,183241728,end,366490624,,:archive.tar

     Play a MPEG-TS file from start offset till end:

	     subfile,,start,32815239,end,0,,:video.ts

   tee
     Writes the output to multiple protocols. The individual outputs are sepa-
     rated by |

	     tee:file://path/to/local/this.avi|file://path/to/local/that.avi

   tcp
     Transmission Control Protocol.

     The required syntax for a TCP url is:

	     tcp://<hostname>:<port>[?<options>]

     options contains a list of &-separated options of the form key=val. Stan-
     dard percent-encoding (and using the plus sign for space) can be used to
     escape keys and values.

     Options can also can be specified via command line options (or in code via
     "AVOption"s).

     The list of supported options follows.

     listen=2|1|0
	 Listen for an incoming connection. 0 disables listen, 1 enables listen
	 in single client mode, 2 enables listen in multi-client mode. Default
	 value is 0.

     local_addr=addr
	 Local IP address of a network interface used for tcp socket connect.

     local_port=port
	 Local port used for tcp socket connect.

     timeout=microseconds
	 Set raise error timeout, expressed in microseconds.

	 This option is only relevant in read mode: if no data arrived in more
	 than this time interval, raise error.

     listen_timeout=milliseconds
	 Set listen timeout, expressed in milliseconds.

     recv_buffer_size=bytes
	 Set receive buffer size, expressed bytes.

     send_buffer_size=bytes
	 Set send buffer size, expressed bytes.

     tcp_nodelay=1|0
	 Set TCP_NODELAY to disable Nagle's algorithm. Default value is 0.

	 Remark: Writing to the socket is currently not optimized to minimize
	 system calls and reduces the efficiency / effect of TCP_NODELAY.

     tcp_mss=bytes
	 Set maximum segment size for outgoing TCP packets, expressed in bytes.

     The following example shows how to setup a listening TCP connection with
     ffmpeg, which is then accessed with ffplay:

	     ffmpeg -i <input> -f <format> tcp://<hostname>:<port>?listen
	     ffplay tcp://<hostname>:<port>

   tls
     Transport Layer Security (TLS) / Secure Sockets Layer (SSL)

     The required syntax for a TLS/SSL url is:

	     tls://<hostname>:<port>[?<options>]

     options contains a list of &-separated options of the form key=val. Stan-
     dard percent-encoding (and using the plus sign for space) can be used to
     escape keys and values.

     Options can also can be specified via command line options (or in code via
     "AVOption"s).

     The list of supported options follows.

     ca_file, cafile=filename
	 A file containing certificate authority (CA) root certificates to treat
	 as trusted. If the linked TLS library contains a default this might not
	 need to be specified for verification to work, but not all libraries
	 and setups have defaults built in.  The file must be in OpenSSL PEM
	 format.

     tls_verify, verify=1|0
	 If enabled, try to verify the peer that we are communicating with.
	 Note, if using OpenSSL, this currently only makes sure that the peer
	 certificate is signed by one of the root certificates in the CA data-
	 base, but it does not validate that the certificate actually matches
	 the host name we are trying to connect to. (With other backends, the
	 host name is validated as well.)

	 This is disabled by default since it requires a CA database to be pro-
	 vided by the caller in many cases.

     cert_file, cert=filename
	 A file containing a certificate to use in the handshake with the peer.
	 (When operating as server, in listen mode, this is more often required
	 by the peer, while client certificates only are mandated in certain se-
	 tups.)

     key_file, key=filename
	 A file containing the private key for the certificate.

     listen=1|0
	 If enabled, listen for connections on the provided port, and assume the
	 server role in the handshake instead of the client role.

     http_proxy
	 The HTTP proxy to tunnel through, e.g. "http://example.com:1234".  The
	 proxy must support the CONNECT method.

     Example command lines:

     To create a TLS/SSL server that serves an input stream.

	     ffmpeg -i <input> -f <format> tls://<hostname>:<port>?listen&cert=<server.crt>&key=<server.key>

     To play back a stream from the TLS/SSL server using ffplay:

	     ffplay tls://<hostname>:<port>

   dtls
     Datagram Transport Layer Security (DTLS)

     The required syntax for a DTLS URL is:

	     dtls://<hostname>:<port>[?<options>]

     options contains a list of &-separated options of the form key=val. Stan-
     dard percent-encoding (and using the plus sign for space) can be used to
     escape keys and values.

     Options can also can be specified via command line options (or in code via
     "AVOption"s).

     DTLS shares most options with TLS, but operates over UDP instead of TCP.

     The list of supported options follows.

     ca_file, cafile=filename
	 A file containing certificate authority (CA) root certificates to treat
	 as trusted. If the linked TLS library contains a default this might not
	 need to be specified for verification to work, but not all libraries
	 and setups have defaults built in.  The file must be in OpenSSL PEM
	 format.

     tls_verify, verify=1|0
	 If enabled, try to verify the peer that we are communicating with.
	 Note, if using OpenSSL, this currently only makes sure that the peer
	 certificate is signed by one of the root certificates in the CA data-
	 base, but it does not validate that the certificate actually matches
	 the host name we are trying to connect to.

	 This is disabled by default since it requires a CA database to be pro-
	 vided by the caller in many cases.

     cert_file, cert=filename
	 A file containing a certificate to use in the handshake with the peer.
	 (When operating as server, in listen mode, this is more often required
	 by the peer, while client certificates only are mandated in certain se-
	 tups.)

     key_file, key=filename
	 A file containing the private key for the certificate.

     cert_pem=string
	 Certificate PEM string

     key_pem=string
	 Private key PEM string

     listen=1|0
	 If enabled, listen for connections on the provided port, and assume the
	 server role in the handshake instead of the client role.

     mtu=size
	 Set the Maximum Transmission Unit (MTU) for DTLS packets.

     use_srtp=1|0
	 Enable the use_srtp DTLS extension.  This is used in WebRTC applica-
	 tions to establish SRTP encryption keys through the DTLS handshake. De-
	 fault is disabled.

     external_sock=1|0
	 Use an external socket instead of creating a new one.	This option only
	 makes sense to pass when interacting with the code via API, enabling
	 this from CLI will cause immediate failure.  Default is disabled.

     Example command lines:

     To create a DTLS server:

	     ffmpeg -listen 1 -i dtls://<hostname>:<port> <output>

     To create a DTLS client and send data to server:

	     ffmpeg -i <input> -f <format> dtls://<hostname>:<port>

   udp
     User Datagram Protocol.

     The required syntax for an UDP URL is:

	     udp://<hostname>:<port>[?<options>]

     options contains a list of &-separated options of the form key=val. Stan-
     dard percent-encoding (and using the plus sign for space) can be used to
     escape keys and values.

     Options can also can be specified via command line options (or in code via
     "AVOption"s).

     In case threading is enabled on the system, a circular buffer is used to
     store the incoming data, which allows one to reduce loss of data due to UDP
     socket buffer overruns. The fifo_size and overrun_nonfatal options are re-
     lated to this buffer.

     The list of supported options follows.

     buffer_size=size
	 Set the UDP maximum socket buffer size in bytes. This is used to set
	 either the receive or send buffer size, depending on what the socket is
	 used for.  Default is 32 KB for output, 384 KB for input.  See also
	 fifo_size.

     bitrate=bitrate
	 If set to nonzero, the output will have the specified constant bitrate
	 if the input has enough packets to sustain it.

     burst_bits=bits
	 When using bitrate this specifies the maximum number of bits in packet
	 bursts.

     localport=port
	 Override the local UDP port to bind with.

     localaddr=addr
	 Local IP address of a network interface used for sending packets or
	 joining multicast groups.

     pkt_size=size
	 Set the size in bytes of UDP packets.

     reuse=1|0
	 Explicitly allow or disallow reusing UDP sockets.

     ttl=ttl
	 Set the time to live value (for multicast only).

     dscp=dscp
	 Set the 6-bit DSCP field for outgoing packets.

     connect=1|0
	 Initialize the UDP socket with connect(). In this case, the destination
	 address can't be changed with ff_udp_set_remote_url later.  If the des-
	 tination 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 ad-
	 dress 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.

     sources=address[,address]
	 Only receive packets sent from the specified addresses. In case of mul-
	 ticast, also subscribe to multicast traffic coming from these addresses
	 only.

     block=address[,address]
	 Ignore packets sent from the specified addresses. In case of multicast,
	 also exclude the source addresses in the multicast subscription.

     fifo_size=units
	 Set the UDP receiving circular buffer size, expressed as a number of
	 packets with size of 188 bytes. If not specified defaults to 7*4096.

     overrun_nonfatal=1|0
	 Survive in case of UDP receiving circular buffer overrun. Default value
	 is 0.

     timeout=microseconds
	 Set raise error timeout, expressed in microseconds.

	 This option is only relevant in read mode: if no data arrived in more
	 than this time interval, raise error.

     broadcast=1|0
	 Explicitly allow or disallow UDP broadcasting.

	 Note that broadcasting may not work properly on networks having a
	 broadcast storm protection.

     Examples

     *	 Use ffmpeg to stream over UDP to a remote endpoint:

		 ffmpeg -i <input> -f <format> udp://<hostname>:<port>

     *	 Use ffmpeg to stream in mpegts format over UDP using 188 sized UDP
	 packets, using a large input buffer:

		 ffmpeg -i <input> -f mpegts udp://<hostname>:<port>?pkt_size=188&buffer_size=65535

     *	 Use ffmpeg to receive over UDP from a remote endpoint:

		 ffmpeg -i udp://[<multicast-address>]:<port> ...

   unix
     Unix local socket

     The required syntax for a Unix socket URL is:

	     unix://<filepath>

     The following parameters can be set via command line options (or in code
     via "AVOption"s):

     timeout
	 Timeout in ms.

     listen
	 Create the Unix socket in listening mode.

     typeSelect socket type.

	 stream Corresponds to SOCK_STREAM (reliable stream-oriented)
	 datagram Corresponds to SOCK_DGRAM (unreliable packet-oriented)
	 seqpacket Corresponds to SOCK_SEQPACKET (reliable packet-oriented)

     pkt_size
	 Maximum packet size for packet-oriented sockets (SOCK_DGRAM and
	 SOCK_SEQPACKET). If greater than zero, this value is used as
	 "max_packet_size". Ignored for SOCK_STREAM. Default is 0.

   zmq
     ZeroMQ asynchronous messaging using the libzmq library.

     This library supports unicast streaming to multiple clients without relying
     on an external server.

     The required syntax for streaming or connecting to a stream is:

	     zmq:tcp://ip-address:port

     Example: Create a localhost stream on port 5555:

	     ffmpeg -re -i input -f mpegts zmq:tcp://127.0.0.1:5555

     Multiple clients may connect to the stream using:

	     ffplay zmq:tcp://127.0.0.1:5555

     Streaming to multiple clients is implemented using a ZeroMQ Pub-Sub pat-
     tern.  The server side binds to a port and publishes data. Clients connect
     to the server (via IP address/port) and subscribe to the stream. The order
     in which the server and client start generally does not matter.

     ffmpeg must be compiled with the --enable-libzmq option to support this
     protocol.

     Options can be set on the ffmpeg/ffplay command line. The following options
     are supported:

     pkt_size
	 Forces the maximum packet size for sending/receiving data. The default
	 value is 131,072 bytes. On the server side, this sets the maximum size
	 of sent packets via ZeroMQ. On the clients, it sets an internal buffer
	 size for receiving packets. Note that pkt_size on the clients should be
	 equal to or greater than pkt_size on the server. Otherwise the received
	 message may be truncated causing decoding errors.

SEE ALSO
     ffmpeg(1), ffplay(1), ffprobe(1), libavformat(3)

AUTHORS
     The FFmpeg developers.

     For details about the authorship, see the Git history of the project
     (https://git.ffmpeg.org/ffmpeg), e.g. by typing the command git log in the
     FFmpeg source directory, or browsing the online repository at
     <https://git.ffmpeg.org/ffmpeg>.

     Maintainers for the specific components are listed in the file MAINTAINERS
     in the source code tree.

							     FFMPEG-PROTOCOLS(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=ffmpeg-protocols&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>

home | help