Provided by: libav-tools_0.8.1-0ubuntu1_amd64 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)