Provided by: libav-tools_0.8.1-0ubuntu1_i386 bug

NAME

       avprobe - avprobe media prober

SYNOPSIS

       avprobe [options] [input_file]

DESCRIPTION

       avprobe gathers information from multimedia streams and prints it in
       human- and machine-readable fashion.

       For example it can be used to check the format of the container used by
       a multimedia stream and the format and type of each media stream
       contained in it.

       If a filename is specified in input, avprobe will try to open and probe
       the file content. If the file cannot be opened or recognized as a
       multimedia file, a positive exit code is returned.

       avprobe may be employed both as a standalone application or in
       combination with a textual filter, which may perform more sophisticated
       processing, e.g. statistical processing or plotting.

       Options are used to list some of the formats supported by avprobe or
       for specifying which information to display, and for setting how
       avprobe will show it.

       avprobe output is designed to be easily parsable by a textual filter,
       and consists of one or more sections of the form:

               [SECTION]
               key1=val1
               ...
               keyN=valN
               [/SECTION]

       Metadata tags stored in the container or in the streams are recognized
       and printed in the corresponding "FORMAT" or "STREAM" section, and are
       prefixed by the string "TAG:".

OPTIONS

       All the numerical options, if not specified otherwise, accept in input
       a string representing a number, which may contain one of the
       International System number postfixes, for example 'K', 'M', 'G'.  If
       'i' is appended after the postfix, powers of 2 are used instead of
       powers of 10. The 'B' postfix multiplies the value for 8, and can be
       appended after another postfix or used alone. This allows using for
       example 'KB', 'MiB', 'G' and 'B' as postfix.

       Options which do not take arguments are boolean options, and set the
       corresponding value to true. They can be set to false by prefixing with
       "no" the option name, for example using "-nofoo" in the command line
       will set to false the boolean option with name "foo".

   Stream specifiers
       Some options are applied per-stream, e.g. bitrate or codec. Stream
       specifiers are used to precisely specify which stream(s) does a given
       option belong to.

       A stream specifier is a string generally appended to the option name
       and separated from it by a colon. E.g. "-codec:a:1 ac3" option contains
       "a:1" stream specifer, which matches the second audio stream. Therefore
       it would select the ac3 codec for the second audio stream.

       A stream specifier can match several stream, the option is then applied
       to all of them. E.g. the stream specifier in "-b:a 128k" matches all
       audio streams.

       An empty stream specifier matches all streams, for example "-codec
       copy" or "-codec: copy" would copy all the streams without reencoding.

       Possible forms of stream specifiers are:

       stream_index
           Matches the stream with this index. E.g. "-threads:1 4" would set
           the thread count for the second stream to 4.

       stream_type[:stream_index]
           stream_type is one of: 'v' for video, 'a' for audio, 's' for
           subtitle, 'd' for data and 't' for attachments. If stream_index is
           given, then matches stream number stream_index of this type.
           Otherwise matches all streams of this type.

       p:program_id[:stream_index]
           If stream_index is given, then matches stream number stream_index
           in program with id program_id. Otherwise matches all streams in
           this program.

   Generic options
       These options are shared amongst the av* tools.

       -L  Show license.

       -h, -?, -help, --help
           Show help.

       -version
           Show version.

       -formats
           Show available formats.

           The fields preceding the format names have the following meanings:

           D   Decoding available

           E   Encoding available

       -codecs
           Show available codecs.

           The fields preceding the codec names have the following meanings:

           D   Decoding available

           E   Encoding available

           V/A/S
               Video/audio/subtitle codec

           S   Codec supports slices

           D   Codec supports direct rendering

           T   Codec can handle input truncated at random locations instead of
               only at frame boundaries

       -bsfs
           Show available bitstream filters.

       -protocols
           Show available protocols.

       -filters
           Show available libavfilter filters.

       -pix_fmts
           Show available pixel formats.

       -sample_fmts
           Show available sample formats.

       -loglevel loglevel | -v loglevel
           Set the logging level used by the library.  loglevel is a number or
           a string containing one of the following values:

           quiet
           panic
           fatal
           error
           warning
           info
           verbose
           debug

           By default the program logs to stderr, if coloring is supported by
           the terminal, colors are used to mark errors and warnings. Log
           coloring can be disabled setting the environment variable
           AV_LOG_FORCE_NOCOLOR or NO_COLOR, or can be forced setting the
           environment variable AV_LOG_FORCE_COLOR.  The use of the
           environment variable NO_COLOR is deprecated and will be dropped in
           a following Libav version.

   AVOptions
       These options are provided directly by the libavformat, libavdevice and
       libavcodec libraries. To see the list of available AVOptions, use the
       -help option. They are separated into two categories:

       generic
           These options can be set for any container, codec or device.
           Generic options are listed under AVFormatContext options for
           containers/devices and under AVCodecContext options for codecs.

       private
           These options are specific to the given container, device or codec.
           Private options are listed under their corresponding
           containers/devices/codecs.

       For example to write an ID3v2.3 header instead of a default ID3v2.4 to
       an MP3 file, use the id3v2_version private option of the MP3 muxer:

               avconv -i input.flac -id3v2_version 3 out.mp3

       All codec AVOptions are obviously per-stream, so the chapter on stream
       specifiers applies to them

       Note -nooption syntax cannot be used for boolean AVOptions, use -option
       0/-option 1.

       Note2 old undocumented way of specifying per-stream AVOptions by
       prepending v/a/s to the options name is now obsolete and will be
       removed soon.

   Main options
       -f format
           Force format to use.

       -unit
           Show the unit of the displayed values.

       -prefix
           Use SI prefixes for the displayed values.  Unless the
           "-byte_binary_prefix" option is used all the prefixes are decimal.

       -byte_binary_prefix
           Force the use of binary prefixes for byte values.

       -sexagesimal
           Use sexagesimal format HH:MM:SS.MICROSECONDS for time values.

       -pretty
           Prettify the format of the displayed values, it corresponds to the
           options "-unit -prefix -byte_binary_prefix -sexagesimal".

       -show_format
           Show information about the container format of the input multimedia
           stream.

           All the container format information is printed within a section
           with name "FORMAT".

       -show_packets
           Show information about each packet contained in the input
           multimedia stream.

           The information for each single packet is printed within a
           dedicated section with name "PACKET".

       -show_streams
           Show information about each media stream contained in the input
           multimedia stream.

           Each media stream information is printed within a dedicated section
           with name "STREAM".

DEMUXERS

       Demuxers are configured elements in Libav which allow to read the
       multimedia streams from a particular type of file.

       When you configure your Libav build, all the supported demuxers are
       enabled by default. You can list all available ones using the configure
       option "--list-demuxers".

       You can disable all the demuxers using the configure option
       "--disable-demuxers", and selectively enable a single demuxer with the
       option "--enable-demuxer=DEMUXER", or disable it with the option
       "--disable-demuxer=DEMUXER".

       The option "-formats" of the ff* tools will display the list of enabled
       demuxers.

       The description of some of the currently available demuxers follows.

   image2
       Image file demuxer.

       This demuxer reads from a list of image files specified by a pattern.

       The pattern may contain the string "%d" or "%0Nd", which specifies the
       position of the characters representing a sequential number in each
       filename matched by the pattern. If the form "%d0Nd" is used, the
       string representing the number in each filename is 0-padded and N is
       the total number of 0-padded digits representing the number. The
       literal character '%' can be specified in the pattern with the string
       "%%".

       If the pattern contains "%d" or "%0Nd", the first filename of the file
       list specified by the pattern must contain a number inclusively
       contained between 0 and 4, all the following numbers must be
       sequential. This limitation may be hopefully fixed.

       The pattern may contain a suffix which is used to automatically
       determine the format of the images contained in the files.

       For example the pattern "img-%03d.bmp" will match a sequence of
       filenames of the form img-001.bmp, img-002.bmp, ..., img-010.bmp, etc.;
       the pattern "i%%m%%g-%d.jpg" will match a sequence of filenames of the
       form i%m%g-1.jpg, i%m%g-2.jpg, ..., i%m%g-10.jpg, etc.

       The size, the pixel format, and the format of each image must be the
       same for all the files in the sequence.

       The following example shows how to use avconv for creating a video from
       the images in the file sequence img-001.jpeg, img-002.jpeg, ...,
       assuming an input framerate of 10 frames per second:

               avconv -i 'img-%03d.jpeg' -r 10 out.mkv

       Note that the pattern must not necessarily contain "%d" or "%0Nd", for
       example to convert a single image file img.jpeg you can employ the
       command:

               avconv -i img.jpeg img.png

   applehttp
       Apple HTTP Live Streaming demuxer.

       This demuxer presents all AVStreams from all variant streams.  The id
       field is set to the bitrate variant index number. By setting the
       discard flags on AVStreams (by pressing 'a' or 'v' in avplay), the
       caller can decide which variant streams to actually receive.  The total
       bitrate of the variant that the stream belongs to is available in a
       metadata key named "variant_bitrate".

MUXERS

       Muxers are configured elements in Libav which allow writing multimedia
       streams to a particular type of file.

       When you configure your Libav build, all the supported muxers are
       enabled by default. You can list all available muxers using the
       configure option "--list-muxers".

       You can disable all the muxers with the configure option
       "--disable-muxers" and selectively enable / disable single muxers with
       the options "--enable-muxer=MUXER" / "--disable-muxer=MUXER".

       The option "-formats" of the ff* tools will display the list of enabled
       muxers.

       A description of some of the currently available muxers follows.

   crc
       CRC (Cyclic Redundancy Check) testing format.

       This muxer computes and prints the Adler-32 CRC of all the input audio
       and video frames. By default audio frames are converted to signed
       16-bit raw audio and video frames to raw video before computing the
       CRC.

       The output of the muxer consists of a single line of the form:
       CRC=0xCRC, where CRC is a hexadecimal number 0-padded to 8 digits
       containing the CRC for all the decoded input frames.

       For example to compute the CRC of the input, and store it in the file
       out.crc:

               avconv -i INPUT -f crc out.crc

       You can print the CRC to stdout with the command:

               avconv -i INPUT -f crc -

       You can select the output format of each frame with avconv by
       specifying the audio and video codec and format. For example to compute
       the CRC of the input audio converted to PCM unsigned 8-bit and the
       input video converted to MPEG-2 video, use the command:

               avconv -i INPUT -c:a pcm_u8 -c:v mpeg2video -f crc -

       See also the framecrc muxer.

   framecrc
       Per-frame CRC (Cyclic Redundancy Check) testing format.

       This muxer computes and prints the Adler-32 CRC for each decoded audio
       and video frame. By default audio frames are converted to signed 16-bit
       raw audio and video frames to raw video before computing the CRC.

       The output of the muxer consists of a line for each audio and video
       frame of the form: stream_index, frame_dts, frame_size, 0xCRC, where
       CRC is a hexadecimal number 0-padded to 8 digits containing the CRC of
       the decoded frame.

       For example to compute the CRC of each decoded frame in the input, and
       store it in the file out.crc:

               avconv -i INPUT -f framecrc out.crc

       You can print the CRC of each decoded frame to stdout with the command:

               avconv -i INPUT -f framecrc -

       You can select the output format of each frame with avconv by
       specifying the audio and video codec and format. For example, to
       compute the CRC of each decoded input audio frame converted to PCM
       unsigned 8-bit and of each decoded input video frame converted to
       MPEG-2 video, use the command:

               avconv -i INPUT -c:a pcm_u8 -c:v mpeg2video -f framecrc -

       See also the crc muxer.

   image2
       Image file muxer.

       The image file muxer writes video frames to image files.

       The output filenames are specified by a pattern, which can be used to
       produce sequentially numbered series of files.  The pattern may contain
       the string "%d" or "%0Nd", this string specifies the position of the
       characters representing a numbering in the filenames. If the form
       "%0Nd" is used, the string representing the number in each filename is
       0-padded to N digits. The literal character '%' can be specified in the
       pattern with the string "%%".

       If the pattern contains "%d" or "%0Nd", the first filename of the file
       list specified will contain the number 1, all the following numbers
       will be sequential.

       The pattern may contain a suffix which is used to automatically
       determine the format of the image files to write.

       For example the pattern "img-%03d.bmp" will specify a sequence of
       filenames of the form img-001.bmp, img-002.bmp, ..., img-010.bmp, etc.
       The pattern "img%%-%d.jpg" will specify a sequence of filenames of the
       form img%-1.jpg, img%-2.jpg, ..., img%-10.jpg, etc.

       The following example shows how to use avconv for creating a sequence
       of files img-001.jpeg, img-002.jpeg, ..., taking one image every second
       from the input video:

               avconv -i in.avi -vsync 1 -r 1 -f image2 'img-%03d.jpeg'

       Note that with avconv, if the format is not specified with the "-f"
       option and the output filename specifies an image file format, the
       image2 muxer is automatically selected, so the previous command can be
       written as:

               avconv -i in.avi -vsync 1 -r 1 'img-%03d.jpeg'

       Note also that the pattern must not necessarily contain "%d" or "%0Nd",
       for example to create a single image file img.jpeg from the input video
       you can employ the command:

               avconv -i in.avi -f image2 -frames:v 1 img.jpeg

   mpegts
       MPEG transport stream muxer.

       This muxer implements ISO 13818-1 and part of ETSI EN 300 468.

       The muxer options are:

       -mpegts_original_network_id number
           Set the original_network_id (default 0x0001). This is unique
           identifier of a network in DVB. Its main use is in the unique
           identification of a service through the path Original_Network_ID,
           Transport_Stream_ID.

       -mpegts_transport_stream_id number
           Set the transport_stream_id (default 0x0001). This identifies a
           transponder in DVB.

       -mpegts_service_id number
           Set the service_id (default 0x0001) also known as program in DVB.

       -mpegts_pmt_start_pid number
           Set the first PID for PMT (default 0x1000, max 0x1f00).

       -mpegts_start_pid number
           Set the first PID for data packets (default 0x0100, max 0x0f00).

       The recognized metadata settings in mpegts muxer are "service_provider"
       and "service_name". If they are not set the default for
       "service_provider" is "Libav" and the default for "service_name" is
       "Service01".

               avconv -i file.mpg -c copy \
                    -mpegts_original_network_id 0x1122 \
                    -mpegts_transport_stream_id 0x3344 \
                    -mpegts_service_id 0x5566 \
                    -mpegts_pmt_start_pid 0x1500 \
                    -mpegts_start_pid 0x150 \
                    -metadata service_provider="Some provider" \
                    -metadata service_name="Some Channel" \
                    -y out.ts

   null
       Null muxer.

       This muxer does not generate any output file, it is mainly useful for
       testing or benchmarking purposes.

       For example to benchmark decoding with avconv you can use the command:

               avconv -benchmark -i INPUT -f null out.null

       Note that the above command does not read or write the out.null file,
       but specifying the output file is required by the avconv syntax.

       Alternatively you can write the command as:

               avconv -benchmark -i INPUT -f null -

   matroska
       Matroska container muxer.

       This muxer implements the matroska and webm container specs.

       The recognized metadata settings in this muxer are:

       title=title name
           Name provided to a single track

       language=language name
           Specifies the language of the track in the Matroska languages form

       STEREO_MODE=mode
           Stereo 3D video layout of two views in a single video track

           mono
               video is not stereo

           left_right
               Both views are arranged side by side, Left-eye view is on the
               left

           bottom_top
               Both views are arranged in top-bottom orientation, Left-eye
               view is at bottom

           top_bottom
               Both views are arranged in top-bottom orientation, Left-eye
               view is on top

           checkerboard_rl
               Each view is arranged in a checkerboard interleaved pattern,
               Left-eye view being first

           checkerboard_lr
               Each view is arranged in a checkerboard interleaved pattern,
               Right-eye view being first

           row_interleaved_rl
               Each view is constituted by a row based interleaving, Right-eye
               view is first row

           row_interleaved_lr
               Each view is constituted by a row based interleaving, Left-eye
               view is first row

           col_interleaved_rl
               Both views are arranged in a column based interleaving manner,
               Right-eye view is first column

           col_interleaved_lr
               Both views are arranged in a column based interleaving manner,
               Left-eye view is first column

           anaglyph_cyan_red
               All frames are in anaglyph format viewable through red-cyan
               filters

           right_left
               Both views are arranged side by side, Right-eye view is on the
               left

           anaglyph_green_magenta
               All frames are in anaglyph format viewable through green-
               magenta filters

           block_lr
               Both eyes laced in one Block, Left-eye view is first

           block_rl
               Both eyes laced in one Block, Right-eye view is first

       For example a 3D WebM clip can be created using the following command
       line:

               avconv -i sample_left_right_clip.mpg -an -c:v libvpx -metadata STEREO_MODE=left_right -y stereo_clip.webm

   segment
       Basic stream segmenter.

       The segmenter muxer outputs streams to a number of separate files of
       nearly fixed duration. Output filename pattern can be set in a fashion
       similar to image2.

       Every segment starts with a video keyframe, if a video stream is
       present.  The segment muxer works best with a single constant frame
       rate video.

       Optionally it can generate a flat list of the created segments, one
       segment per line.

       segment_format format
           Override the inner container format, by default it is guessed by
           the filename extension.

       segment_time t
           Set segment duration to t seconds.

       segment_list name
           Generate also a listfile named name.

       segment_list_size size
           Overwrite the listfile once it reaches size entries.

               avconv -i in.mkv -c copy -map 0 -f segment -list out.list out%03d.nut

PROTOCOLS

       Protocols are configured elements in Libav which allow to access
       resources which require the use of a particular protocol.

       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".

       You can disable all the protocols using the configure option
       "--disable-protocols", and selectively enable a protocol using the
       option "--enable-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.

       A description of the currently available protocols follows.

   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
       "+proto" after the applehttp URI scheme name, where proto is either
       "file" or "http".

               applehttp://host/path/to/remote/resource.m3u8
               applehttp+http://host/path/to/remote/resource.m3u8
               applehttp+file://path/to/local/resource.m3u8

   concat
       Physical concatenation protocol.

       Allow to read and seek from many resource in sequence as if they were a
       unique resource.

       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
       concatenated, each one possibly specifying a distinct protocol.

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

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

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

   file
       File access protocol.

       Allow to read from or read to a file.

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

               avconv -i file:input.mpeg output.mpeg

       The ff* tools default to the file protocol, that is a resource
       specified with the name "FILE.mpeg" is interpreted as the URL
       "file:FILE.mpeg".

   gopher
       Gopher protocol.

   http
       HTTP (Hyper Text Transfer Protocol).

   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.
               avconv -i input.flv -f avi -y md5:output.avi.md5

               # Write the MD5 hash of the encoded AVI file to stdout.
               avconv -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.

       Allow to read and write from UNIX pipes.

       The accepted syntax is:

               pipe:[<number>]

       number is the number corresponding to the file descriptor 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 avconv:

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

       For writing to stdout with avconv:

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

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

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

       The accepted parameters are:

       server
           The address of the RTMP server.

       port
           The 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.).

       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:".

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

               avplay rtmp://myserver/vod/sample

   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
       configuration. 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
       avconv:

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

       To play the same stream using avplay:

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

   rtp
       Real-Time Protocol.

   rtsp
       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
       supporting it (currently Darwin Streaming Server and Mischa
       Spiegelmock's
        RTSP server ("http://github.com/revmischa/rtsp-server")).

       The required syntax for a RTSP url is:

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

       The following options (set on the avconv/avplay command line, or set in
       code via "AVOption"s or in "avformat_open_input"), are supported:

       Flags for "rtsp_transport":

       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.

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

       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.

       Flags for "rtsp_flags":

       filter_src
           Accept packets only from negotiated peer address and port.

       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). In order for this to be enabled, a maximum delay must be
       specified in the "max_delay" field of AVFormatContext.

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

       Example command lines:

       To watch a stream over UDP, with a max reordering delay of 0.5 seconds:

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

       To watch a stream tunneled over HTTP:

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

       To send a stream in realtime to a RTSP server, for others to watch:

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

   sap
       Session Announcement Protocol (RFC 2974). This is not technically a
       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.

       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 announcement 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 libavformat 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:

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

       Similarly, for watching in avplay:

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

       And for watching in avplay, over IPv6:

               avconv -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
       omitted, 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
       address:

               avplay sap://

       To play back the first stream announced on one the default IPv6 SAP
       multicast address:

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

   tcp
       Trasmission Control Protocol.

       The required syntax for a TCP url is:

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

       listen
           Listen for an incoming connection

                   avconv -i <input> -f <format> tcp://<hostname>:<port>?listen
                   avplay tcp://<hostname>:<port>

   udp
       User Datagram Protocol.

       The required syntax for a UDP url is:

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

       options contains a list of &-seperated options of the form key=val.
       Follow the list of supported options.

       buffer_size=size
           set the UDP buffer size in bytes

       localport=port
           override the local UDP port to bind with

       localaddr=addr
           Choose the local IP address. This is useful e.g. if sending
           multicast and the host has multiple interfaces, where the user can
           choose which interface to send on by specifying the IP address of
           that interface.

       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)

       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 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.

       Some usage examples of the udp protocol with avconv follow.

       To stream over UDP to a remote endpoint:

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

       To stream in mpegts format over UDP using 188 sized UDP packets, using
       a large input buffer:

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

       To receive over UDP from a remote endpoint:

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

INPUT DEVICES

       Input devices are configured elements in Libav which allow to access
       the data coming from a multimedia device attached to your system.

       When you configure your Libav build, all the supported input devices
       are enabled by default. You can list all available ones using the
       configure option "--list-indevs".

       You can disable all the input devices using the configure option
       "--disable-indevs", and selectively enable an input device using the
       option "--enable-indev=INDEV", or you can disable a particular input
       device using the option "--disable-indev=INDEV".

       The option "-formats" of the ff* tools will display the list of
       supported input devices (amongst the demuxers).

       A description of the currently available input devices follows.

   alsa
       ALSA (Advanced Linux Sound Architecture) input device.

       To enable this input device during configuration you need libasound
       installed on your system.

       This device allows capturing from an ALSA device. The name of the
       device to capture has to be an ALSA card identifier.

       An ALSA identifier has the syntax:

               hw:<CARD>[,<DEV>[,<SUBDEV>]]

       where the DEV and SUBDEV components are optional.

       The three arguments (in order: CARD,DEV,SUBDEV) specify card number or
       identifier, device number and subdevice number (-1 means any).

       To see the list of cards currently recognized by your system check the
       files /proc/asound/cards and /proc/asound/devices.

       For example to capture with avconv from an ALSA device with card id 0,
       you may run the command:

               avconv -f alsa -i hw:0 alsaout.wav

       For more information see:
       <http://www.alsa-project.org/alsa-doc/alsa-lib/pcm.html>

   bktr
       BSD video input device.

   dv1394
       Linux DV 1394 input device.

   fbdev
       Linux framebuffer input device.

       The Linux framebuffer is a graphic hardware-independent abstraction
       layer to show graphics on a computer monitor, typically on the console.
       It is accessed through a file device node, usually /dev/fb0.

       For more detailed information read the file
       Documentation/fb/framebuffer.txt included in the Linux source tree.

       To record from the framebuffer device /dev/fb0 with avconv:

               avconv -f fbdev -r 10 -i /dev/fb0 out.avi

       You can take a single screenshot image with the command:

               avconv -f fbdev -frames:v 1 -r 1 -i /dev/fb0 screenshot.jpeg

       See also <http://linux-fbdev.sourceforge.net/>, and fbset(1).

   jack
       JACK input device.

       To enable this input device during configuration you need libjack
       installed on your system.

       A JACK input device creates one or more JACK writable clients, one for
       each audio channel, with name client_name:input_N, where client_name is
       the name provided by the application, and N is a number which
       identifies the channel.  Each writable client will send the acquired
       data to the Libav input device.

       Once you have created one or more JACK readable clients, you need to
       connect them to one or more JACK writable clients.

       To connect or disconnect JACK clients you can use the jack_connect and
       jack_disconnect programs, or do it through a graphical interface, for
       example with qjackctl.

       To list the JACK clients and their properties you can invoke the
       command jack_lsp.

       Follows an example which shows how to capture a JACK readable client
       with avconv.

               # Create a JACK writable client with name "libav".
               $ avconv -f jack -i libav -y out.wav

               # Start the sample jack_metro readable client.
               $ jack_metro -b 120 -d 0.2 -f 4000

               # List the current JACK clients.
               $ jack_lsp -c
               system:capture_1
               system:capture_2
               system:playback_1
               system:playback_2
               libav:input_1
               metro:120_bpm

               # Connect metro to the avconv writable client.
               $ jack_connect metro:120_bpm libav:input_1

       For more information read: <http://jackaudio.org/>

   libdc1394
       IIDC1394 input device, based on libdc1394 and libraw1394.

   oss
       Open Sound System input device.

       The filename to provide to the input device is the device node
       representing the OSS input device, and is usually set to /dev/dsp.

       For example to grab from /dev/dsp using avconv use the command:

               avconv -f oss -i /dev/dsp /tmp/oss.wav

       For more information about OSS see:
       <http://manuals.opensound.com/usersguide/dsp.html>

   pulse
       pulseaudio input device.

       To enable this input device during configuration you need libpulse-
       simple installed in your system.

       The filename to provide to the input device is a source device or the
       string "default"

       To list the pulse source devices and their properties you can invoke
       the command pactl list sources.

               avconv -f pulse -i default /tmp/pulse.wav

       server AVOption

       The syntax is:

               -server <server name>

       Connects to a specific server.

       name AVOption

       The syntax is:

               -name <application name>

       Specify the application name pulse will use when showing active
       clients, by default it is "libav"

       stream_name AVOption

       The syntax is:

               -stream_name <stream name>

       Specify the stream name pulse will use when showing active streams, by
       default it is "record"

       sample_rate AVOption

       The syntax is:

               -sample_rate <samplerate>

       Specify the samplerate in Hz, by default 48kHz is used.

       channels AVOption

       The syntax is:

               -channels <N>

       Specify the channels in use, by default 2 (stereo) is set.

       frame_size AVOption

       The syntax is:

               -frame_size <bytes>

       Specify the number of byte per frame, by default it is set to 1024.

       fragment_size AVOption

       The syntax is:

               -fragment_size <bytes>

       Specify the minimal buffering fragment in pulseaudio, it will affect
       the audio latency. By default it is unset.

   sndio
       sndio input device.

       To enable this input device during configuration you need libsndio
       installed on your system.

       The filename to provide to the input device is the device node
       representing the sndio input device, and is usually set to /dev/audio0.

       For example to grab from /dev/audio0 using avconv use the command:

               avconv -f sndio -i /dev/audio0 /tmp/oss.wav

   video4linux and video4linux2
       Video4Linux and Video4Linux2 input video devices.

       The name of the device to grab is a file device node, usually Linux
       systems tend to automatically create such nodes when the device (e.g.
       an USB webcam) is plugged into the system, and has a name of the kind
       /dev/videoN, where N is a number associated to the device.

       Video4Linux and Video4Linux2 devices only support a limited set of
       widthxheight sizes and framerates. You can check which are supported
       for example with the command dov4l for Video4Linux devices and using
       -list_formats all for Video4Linux2 devices.

       If the size for the device is set to 0x0, the input device will try to
       autodetect the size to use.  Only for the video4linux2 device, if the
       frame rate is set to 0/0 the input device will use the frame rate value
       already set in the driver.

       Video4Linux support is deprecated since Linux 2.6.30, and will be
       dropped in later versions.

       Follow some usage examples of the video4linux devices with the ff*
       tools.

               # Grab and show the input of a video4linux device, frame rate is set
               # to the default of 25/1.
               avplay -s 320x240 -f video4linux /dev/video0

               # Grab and show the input of a video4linux2 device, autoadjust size.
               avplay -f video4linux2 /dev/video0

               # Grab and record the input of a video4linux2 device, autoadjust size,
               # frame rate value defaults to 0/0 so it is read from the video4linux2
               # driver.
               avconv -f video4linux2 -i /dev/video0 out.mpeg

   vfwcap
       VfW (Video for Windows) capture input device.

       The filename passed as input is the capture driver number, ranging from
       0 to 9. You may use "list" as filename to print a list of drivers. Any
       other filename will be interpreted as device number 0.

   x11grab
       X11 video input device.

       This device allows to capture a region of an X11 display.

       The filename passed as input has the syntax:

               [<hostname>]:<display_number>.<screen_number>[+<x_offset>,<y_offset>]

       hostname:display_number.screen_number specifies the X11 display name of
       the screen to grab from. hostname can be ommitted, and defaults to
       "localhost". The environment variable DISPLAY contains the default
       display name.

       x_offset and y_offset specify the offsets of the grabbed area with
       respect to the top-left border of the X11 screen. They default to 0.

       Check the X11 documentation (e.g. man X) for more detailed information.

       Use the dpyinfo program for getting basic information about the
       properties of your X11 display (e.g. grep for "name" or "dimensions").

       For example to grab from :0.0 using avconv:

               avconv -f x11grab -r 25 -s cif -i :0.0 out.mpg

               # Grab at position 10,20.
               avconv -f x11grab -r 25 -s cif -i :0.0+10,20 out.mpg

       follow_mouse AVOption

       The syntax is:

               -follow_mouse centered|<PIXELS>

       When it is specified with "centered", the grabbing region follows the
       mouse pointer and keeps the pointer at the center of region; otherwise,
       the region follows only when the mouse pointer reaches within PIXELS
       (greater than zero) to the edge of region.

       For example:

               avconv -f x11grab -follow_mouse centered -r 25 -s cif -i :0.0 out.mpg

               # Follows only when the mouse pointer reaches within 100 pixels to edge
               avconv -f x11grab -follow_mouse 100 -r 25 -s cif -i :0.0 out.mpg

       show_region AVOption

       The syntax is:

               -show_region 1

       If show_region AVOption is specified with 1, then the grabbing region
       will be indicated on screen. With this option, it's easy to know what
       is being grabbed if only a portion of the screen is grabbed.

       For example:

               avconv -f x11grab -show_region 1 -r 25 -s cif -i :0.0+10,20 out.mpg

               # With follow_mouse
               avconv -f x11grab -follow_mouse centered -show_region 1  -r 25 -s cif -i :0.0 out.mpg

SEE ALSO

       avconv(1), avplay(1) and the Libav HTML documentation

AUTHORS

       The Libav developers

                                  2012-03-22                        AVPROBE(1)