Provided by: ffmpeg_3.3.4-2_amd64 bug

NAME

       ffmpeg-devices - FFmpeg devices

DESCRIPTION

       This document describes the input and output devices provided by the libavdevice library.

DEVICE OPTIONS

       The libavdevice library provides the same interface as libavformat. Namely, an input
       device is considered like a demuxer, and an output device like a muxer, and the interface
       and generic device options are the same provided by libavformat (see the ffmpeg-formats
       manual).

       In addition each input or output device may support so-called private options, which are
       specific for that component.

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

INPUT DEVICES

       Input devices are configured elements in FFmpeg which enable accessing the data coming
       from a multimedia device attached to your system.

       When you configure your FFmpeg 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 "-devices" of the ff* tools will display the list of supported input devices.

       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 ffmpeg from an ALSA device with card id 0, you may run the
       command:

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

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

       Options

       sample_rate
           Set the sample rate in Hz. Default is 48000.

       channels
           Set the number of channels. Default is 2.

   avfoundation
       AVFoundation input device.

       AVFoundation is the currently recommended framework by Apple for streamgrabbing on OSX >=
       10.7 as well as on iOS.  The older QTKit framework has been marked deprecated since OSX
       version 10.7.

       The input filename has to be given in the following syntax:

               -i "[[VIDEO]:[AUDIO]]"

       The first entry selects the video input while the latter selects the audio input.  The
       stream has to be specified by the device name or the device index as shown by the device
       list.  Alternatively, the video and/or audio input device can be chosen by index using the

           B<-video_device_index E<lt>INDEXE<gt>>

       and/or

           B<-audio_device_index E<lt>INDEXE<gt>>

       , overriding any device name or index given in the input filename.

       All available devices can be enumerated by using -list_devices true, listing all device
       names and corresponding indices.

       There are two device name aliases:

       "default"
           Select the AVFoundation default device of the corresponding type.

       "none"
           Do not record the corresponding media type.  This is equivalent to specifying an empty
           device name or index.

       Options

       AVFoundation supports the following options:

       -list_devices <TRUE|FALSE>
           If set to true, a list of all available input devices is given showing all device
           names and indices.

       -video_device_index <INDEX>
           Specify the video device by its index. Overrides anything given in the input filename.

       -audio_device_index <INDEX>
           Specify the audio device by its index. Overrides anything given in the input filename.

       -pixel_format <FORMAT>
           Request the video device to use a specific pixel format.  If the specified format is
           not supported, a list of available formats is given and the first one in this list is
           used instead. Available pixel formats are: "monob, rgb555be, rgb555le, rgb565be,
           rgb565le, rgb24, bgr24, 0rgb, bgr0, 0bgr, rgb0,
            bgr48be, uyvy422, yuva444p, yuva444p16le, yuv444p, yuv422p16, yuv422p10, yuv444p10,
            yuv420p, nv12, yuyv422, gray"

       -framerate
           Set the grabbing frame rate. Default is "ntsc", corresponding to a frame rate of
           "30000/1001".

       -video_size
           Set the video frame size.

       -capture_cursor
           Capture the mouse pointer. Default is 0.

       -capture_mouse_clicks
           Capture the screen mouse clicks. Default is 0.

       Examples

       ·   Print the list of AVFoundation supported devices and exit:

                   $ ffmpeg -f avfoundation -list_devices true -i ""

       ·   Record video from video device 0 and audio from audio device 0 into out.avi:

                   $ ffmpeg -f avfoundation -i "0:0" out.avi

       ·   Record video from video device 2 and audio from audio device 1 into out.avi:

                   $ ffmpeg -f avfoundation -video_device_index 2 -i ":1" out.avi

       ·   Record video from the system default video device using the pixel format bgr0 and do
           not record any audio into out.avi:

                   $ ffmpeg -f avfoundation -pixel_format bgr0 -i "default:none" out.avi

   bktr
       BSD video input device.

       Options

       framerate
           Set the frame rate.

       video_size
           Set the video frame size. Default is "vga".

       standard
           Available values are:

           pal
           ntsc
           secam
           paln
           palm
           ntscj

   decklink
       The decklink input device provides capture capabilities for Blackmagic DeckLink devices.

       To enable this input device, you need the Blackmagic DeckLink SDK and you need to
       configure with the appropriate "--extra-cflags" and "--extra-ldflags".  On Windows, you
       need to run the IDL files through widl.

       DeckLink is very picky about the formats it supports. Pixel format is uyvy422 or v210,
       framerate and video size must be determined for your device with -list_formats 1. Audio
       sample rate is always 48 kHz and the number of channels can be 2, 8 or 16. Note that all
       audio channels are bundled in one single audio track.

       Options

       list_devices
           If set to true, print a list of devices and exit.  Defaults to false.

       list_formats
           If set to true, print a list of supported formats and exit.  Defaults to false.

       format_code <FourCC>
           This sets the input video format to the format given by the FourCC. To see the
           supported values of your device(s) use list_formats.  Note that there is a FourCC 'pal
           ' that can also be used as pal (3 letters).

       bm_v210
           If set to 1, video is captured in 10 bit v210 instead of uyvy422. Not all Blackmagic
           devices support this option.

       teletext_lines
           If set to nonzero, an additional teletext stream will be captured from the vertical
           ancillary data. This option is a bitmask of the VBI lines checked, specifically lines
           6 to 22, and lines 318 to 335. Line 6 is the LSB in the mask.  Selected lines which do
           not contain teletext information will be ignored. You can use the special all constant
           to select all possible lines, or standard to skip lines 6, 318 and 319, which are not
           compatible with all receivers. Capturing teletext only works for SD PAL sources in 8
           bit mode.  To use this option, ffmpeg needs to be compiled with "--enable-libzvbi".

       channels
           Defines number of audio channels to capture. Must be 2, 8 or 16.  Defaults to 2.

       duplex_mode
           Sets the decklink device duplex mode. Must be unset, half or full.  Defaults to unset.

       video_input
           Sets the video input source. Must be unset, sdi, hdmi, optical_sdi, component,
           composite or s_video.  Defaults to unset.

       audio_input
           Sets the audio input source. Must be unset, embedded, aes_ebu, analog, analog_xlr,
           analog_rca or microphone. Defaults to unset.

       video_pts
           Sets the video packet timestamp source. Must be video, audio, reference or wallclock.
           Defaults to video.

       audio_pts
           Sets the audio packet timestamp source. Must be video, audio, reference or wallclock.
           Defaults to audio.

       draw_bars
           If set to true, color bars are drawn in the event of a signal loss.  Defaults to true.

       Examples

       ·   List input devices:

                   ffmpeg -f decklink -list_devices 1 -i dummy

       ·   List supported formats:

                   ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'

       ·   Capture video clip at 1080i50:

                   ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -acodec copy -vcodec copy output.avi

       ·   Capture video clip at 1080i50 10 bit:

                   ffmpeg -bm_v210 1 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -acodec copy -vcodec copy output.avi

       ·   Capture video clip at 1080i50 with 16 audio channels:

                   ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -acodec copy -vcodec copy output.avi

   dshow
       Windows DirectShow input device.

       DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.  Currently
       only audio and video devices are supported.

       Multiple devices may be opened as separate inputs, but they may also be opened on the same
       input, which should improve synchronism between them.

       The input name should be in the format:

               <TYPE>=<NAME>[:<TYPE>=<NAME>]

       where TYPE can be either audio or video, and NAME is the device's name or alternative
       name..

       Options

       If no options are specified, the device's defaults are used.  If the device does not
       support the requested options, it will fail to open.

       video_size
           Set the video size in the captured video.

       framerate
           Set the frame rate in the captured video.

       sample_rate
           Set the sample rate (in Hz) of the captured audio.

       sample_size
           Set the sample size (in bits) of the captured audio.

       channels
           Set the number of channels in the captured audio.

       list_devices
           If set to true, print a list of devices and exit.

       list_options
           If set to true, print a list of selected device's options and exit.

       video_device_number
           Set video device number for devices with the same name (starts at 0, defaults to 0).

       audio_device_number
           Set audio device number for devices with the same name (starts at 0, defaults to 0).

       pixel_format
           Select pixel format to be used by DirectShow. This may only be set when the video
           codec is not set or set to rawvideo.

       audio_buffer_size
           Set audio device buffer size in milliseconds (which can directly impact latency,
           depending on the device).  Defaults to using the audio device's default buffer size
           (typically some multiple of 500ms).  Setting this value too low can degrade
           performance.  See also
           <http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx>

       video_pin_name
           Select video capture pin to use by name or alternative name.

       audio_pin_name
           Select audio capture pin to use by name or alternative name.

       crossbar_video_input_pin_number
           Select video input pin number for crossbar device. This will be routed to the crossbar
           device's Video Decoder output pin.  Note that changing this value can affect future
           invocations (sets a new default) until system reboot occurs.

       crossbar_audio_input_pin_number
           Select audio input pin number for crossbar device. This will be routed to the crossbar
           device's Audio Decoder output pin.  Note that changing this value can affect future
           invocations (sets a new default) until system reboot occurs.

       show_video_device_dialog
           If set to true, before capture starts, popup a display dialog to the end user,
           allowing them to change video filter properties and configurations manually.  Note
           that for crossbar devices, adjusting values in this dialog may be needed at times to
           toggle between PAL (25 fps) and NTSC (29.97) input frame rates, sizes, interlacing,
           etc.  Changing these values can enable different scan rates/frame rates and avoiding
           green bars at the bottom, flickering scan lines, etc.  Note that with some devices,
           changing these properties can also affect future invocations (sets new defaults) until
           system reboot occurs.

       show_audio_device_dialog
           If set to true, before capture starts, popup a display dialog to the end user,
           allowing them to change audio filter properties and configurations manually.

       show_video_crossbar_connection_dialog
           If set to true, before capture starts, popup a display dialog to the end user,
           allowing them to manually modify crossbar pin routings, when it opens a video device.

       show_audio_crossbar_connection_dialog
           If set to true, before capture starts, popup a display dialog to the end user,
           allowing them to manually modify crossbar pin routings, when it opens an audio device.

       show_analog_tv_tuner_dialog
           If set to true, before capture starts, popup a display dialog to the end user,
           allowing them to manually modify TV channels and frequencies.

       show_analog_tv_tuner_audio_dialog
           If set to true, before capture starts, popup a display dialog to the end user,
           allowing them to manually modify TV audio (like mono vs. stereo, Language A,B or C).

       audio_device_load
           Load an audio capture filter device from file instead of searching it by name. It may
           load additional parameters too, if the filter supports the serialization of its
           properties to.  To use this an audio capture source has to be specified, but it can be
           anything even fake one.

       audio_device_save
           Save the currently used audio capture filter device and its parameters (if the filter
           supports it) to a file.  If a file with the same name exists it will be overwritten.

       video_device_load
           Load a video capture filter device from file instead of searching it by name. It may
           load additional parameters too, if the filter supports the serialization of its
           properties to.  To use this a video capture source has to be specified, but it can be
           anything even fake one.

       video_device_save
           Save the currently used video capture filter device and its parameters (if the filter
           supports it) to a file.  If a file with the same name exists it will be overwritten.

       Examples

       ·   Print the list of DirectShow supported devices and exit:

                   $ ffmpeg -list_devices true -f dshow -i dummy

       ·   Open video device Camera:

                   $ ffmpeg -f dshow -i video="Camera"

       ·   Open second video device with name Camera:

                   $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"

       ·   Open video device Camera and audio device Microphone:

                   $ ffmpeg -f dshow -i video="Camera":audio="Microphone"

       ·   Print the list of supported options in selected device and exit:

                   $ ffmpeg -list_options true -f dshow -i video="Camera"

       ·   Specify pin names to capture by name or alternative name, specify alternative device
           name:

                   $ ffmpeg -f dshow -audio_pin_name "Audio Out" -video_pin_name 2 -i video=video="@device_pnp_\\?\pci#ven_1a0a&dev_6200&subsys_62021461&rev_01#4&e2c7dd6&0&00e1#{65e8773d-8f56-11d0-a3b9-00a0c9223196}\{ca465100-deb0-4d59-818f-8c477184adf6}":audio="Microphone"

       ·   Configure a crossbar device, specifying crossbar pins, allow user to adjust video
           capture properties at startup:

                   $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
                        -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"

   dv1394
       Linux DV 1394 input device.

       Options

       framerate
           Set the frame rate. Default is 25.

       standard
           Available values are:

           pal
           ntsc

           Default value is "ntsc".

   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.

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

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

               ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi

       You can take a single screenshot image with the command:

               ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg

       Options

       framerate
           Set the frame rate. Default is 25.

   gdigrab
       Win32 GDI-based screen capture device.

       This device allows you to capture a region of the display on Windows.

       There are two options for the input filename:

               desktop

       or

               title=<window_title>

       The first option will capture the entire desktop, or a fixed region of the desktop. The
       second option will instead capture the contents of a single window, regardless of its
       position on the screen.

       For example, to grab the entire desktop using ffmpeg:

               ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg

       Grab a 640x480 region at position "10,20":

               ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg

       Grab the contents of the window named "Calculator"

               ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg

       Options

       draw_mouse
           Specify whether to draw the mouse pointer. Use the value 0 to not draw the pointer.
           Default value is 1.

       framerate
           Set the grabbing frame rate. Default value is "ntsc", corresponding to a frame rate of
           "30000/1001".

       show_region
           Show grabbed region on screen.

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

           Note that show_region is incompatible with grabbing the contents of a single window.

           For example:

                   ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg

       video_size
           Set the video frame size. The default is to capture the full screen if desktop is
           selected, or the full window size if title=window_title is selected.

       offset_x
           When capturing a region with video_size, set the distance from the left edge of the
           screen or desktop.

           Note that the offset calculation is from the top left corner of the primary monitor on
           Windows. If you have a monitor positioned to the left of your primary monitor, you
           will need to use a negative offset_x value to move the region to that monitor.

       offset_y
           When capturing a region with video_size, set the distance from the top edge of the
           screen or desktop.

           Note that the offset calculation is from the top left corner of the primary monitor on
           Windows. If you have a monitor positioned above your primary monitor, you will need to
           use a negative offset_y value to move the region to that monitor.

   iec61883
       FireWire DV/HDV input device using libiec61883.

       To enable this input device, you need libiec61883, libraw1394 and libavc1394 installed on
       your system. Use the configure option "--enable-libiec61883" to compile with the device
       enabled.

       The iec61883 capture device supports capturing from a video device connected via IEEE1394
       (FireWire), using libiec61883 and the new Linux FireWire stack (juju). This is the default
       DV/HDV input method in Linux Kernel 2.6.37 and later, since the old FireWire stack was
       removed.

       Specify the FireWire port to be used as input file, or "auto" to choose the first port
       connected.

       Options

       dvtype
           Override autodetection of DV/HDV. This should only be used if auto detection does not
           work, or if usage of a different device type should be prohibited. Treating a DV
           device as HDV (or vice versa) will not work and result in undefined behavior.  The
           values auto, dv and hdv are supported.

       dvbuffer
           Set maximum size of buffer for incoming data, in frames. For DV, this is an exact
           value. For HDV, it is not frame exact, since HDV does not have a fixed frame size.

       dvguid
           Select the capture device by specifying its GUID. Capturing will only be performed
           from the specified device and fails if no device with the given GUID is found. This is
           useful to select the input if multiple devices are connected at the same time.  Look
           at /sys/bus/firewire/devices to find out the GUIDs.

       Examples

       ·   Grab and show the input of a FireWire DV/HDV device.

                   ffplay -f iec61883 -i auto

       ·   Grab and record the input of a FireWire DV/HDV device, using a packet buffer of 100000
           packets if the source is HDV.

                   ffmpeg -f iec61883 -i auto -hdvbuffer 100000 out.mpg

   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 FFmpeg 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 ffmpeg.

               # Create a JACK writable client with name "ffmpeg".
               $ ffmpeg -f jack -i ffmpeg -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
               ffmpeg:input_1
               metro:120_bpm

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

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

       Options

       channels
           Set the number of channels. Default is 2.

   lavfi
       Libavfilter input virtual device.

       This input device reads data from the open output pads of a libavfilter filtergraph.

       For each filtergraph open output, the input device will create a corresponding stream
       which is mapped to the generated output. Currently only video data is supported. The
       filtergraph is specified through the option graph.

       Options

       graph
           Specify the filtergraph to use as input. Each video open output must be labelled by a
           unique string of the form "outN", where N is a number starting from 0 corresponding to
           the mapped input stream generated by the device.  The first unlabelled output is
           automatically assigned to the "out0" label, but all the others need to be specified
           explicitly.

           The suffix "+subcc" can be appended to the output label to create an extra stream with
           the closed captions packets attached to that output (experimental; only for EIA-608 /
           CEA-708 for now).  The subcc streams are created after all the normal streams, in the
           order of the corresponding stream.  For example, if there is "out19+subcc",
           "out7+subcc" and up to "out42", the stream #43 is subcc for stream #7 and stream #44
           is subcc for stream #19.

           If not specified defaults to the filename specified for the input device.

       graph_file
           Set the filename of the filtergraph to be read and sent to the other filters. Syntax
           of the filtergraph is the same as the one specified by the option graph.

       dumpgraph
           Dump graph to stderr.

       Examples

       ·   Create a color video stream and play it back with ffplay:

                   ffplay -f lavfi -graph "color=c=pink [out0]" dummy

       ·   As the previous example, but use filename for specifying the graph description, and
           omit the "out0" label:

                   ffplay -f lavfi color=c=pink

       ·   Create three different video test filtered sources and play them:

                   ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3

       ·   Read an audio stream from a file using the amovie source and play it back with ffplay:

                   ffplay -f lavfi "amovie=test.wav"

       ·   Read an audio stream and a video stream and play it back with ffplay:

                   ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"

       ·   Dump decoded frames to images and closed captions to a file (experimental):

                   ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin

   libcdio
       Audio-CD input device based on libcdio.

       To enable this input device during configuration you need libcdio installed on your
       system. It requires the configure option "--enable-libcdio".

       This device allows playing and grabbing from an Audio-CD.

       For example to copy with ffmpeg the entire Audio-CD in /dev/sr0, you may run the command:

               ffmpeg -f libcdio -i /dev/sr0 cd.wav

       Options

       speed
           Set drive reading speed. Default value is 0.

           The speed is specified CD-ROM speed units. The speed is set through the libcdio
           "cdio_cddap_speed_set" function. On many CD-ROM drives, specifying a value too large
           will result in using the fastest speed.

       paranoia_mode
           Set paranoia recovery mode flags. It accepts one of the following values:

           disable
           verify
           overlap
           neverskip
           full

           Default value is disable.

           For more information about the available recovery modes, consult the paranoia project
           documentation.

   libdc1394
       IIDC1394 input device, based on libdc1394 and libraw1394.

       Requires the configure option "--enable-libdc1394".

   openal
       The OpenAL input device provides audio capture on all systems with a working OpenAL 1.1
       implementation.

       To enable this input device during configuration, you need OpenAL headers and libraries
       installed on your system, and need to configure FFmpeg with "--enable-openal".

       OpenAL headers and libraries should be provided as part of your OpenAL implementation, or
       as an additional download (an SDK). Depending on your installation you may need to specify
       additional flags via the "--extra-cflags" and "--extra-ldflags" for allowing the build
       system to locate the OpenAL headers and libraries.

       An incomplete list of OpenAL implementations follows:

       Creative
           The official Windows implementation, providing hardware acceleration with supported
           devices and software fallback.  See <http://openal.org/>.

       OpenAL Soft
           Portable, open source (LGPL) software implementation. Includes backends for the most
           common sound APIs on the Windows, Linux, Solaris, and BSD operating systems.  See
           <http://kcat.strangesoft.net/openal.html>.

       Apple
           OpenAL is part of Core Audio, the official Mac OS X Audio interface.  See
           <http://developer.apple.com/technologies/mac/audio-and-video.html>

       This device allows one to capture from an audio input device handled through OpenAL.

       You need to specify the name of the device to capture in the provided filename. If the
       empty string is provided, the device will automatically select the default device. You can
       get the list of the supported devices by using the option list_devices.

       Options

       channels
           Set the number of channels in the captured audio. Only the values 1 (monaural) and 2
           (stereo) are currently supported.  Defaults to 2.

       sample_size
           Set the sample size (in bits) of the captured audio. Only the values 8 and 16 are
           currently supported. Defaults to 16.

       sample_rate
           Set the sample rate (in Hz) of the captured audio.  Defaults to 44.1k.

       list_devices
           If set to true, print a list of devices and exit.  Defaults to false.

       Examples

       Print the list of OpenAL supported devices and exit:

               $ ffmpeg -list_devices true -f openal -i dummy out.ogg

       Capture from the OpenAL device DR-BT101 via PulseAudio:

               $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg

       Capture from the default device (note the empty string '' as filename):

               $ ffmpeg -f openal -i '' out.ogg

       Capture from two devices simultaneously, writing to two different files, within the same
       ffmpeg command:

               $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg

       Note: not all OpenAL implementations support multiple simultaneous capture - try the
       latest OpenAL Soft if the above does not work.

   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 ffmpeg use the command:

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

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

       Options

       sample_rate
           Set the sample rate in Hz. Default is 48000.

       channels
           Set the number of channels. Default is 2.

   pulse
       PulseAudio input device.

       To enable this output device you need to configure FFmpeg with "--enable-libpulse".

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

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

       More information about PulseAudio can be found on <http://www.pulseaudio.org>.

       Options

       server
           Connect to a specific PulseAudio server, specified by an IP address.  Default server
           is used when not provided.

       name
           Specify the application name PulseAudio will use when showing active clients, by
           default it is the "LIBAVFORMAT_IDENT" string.

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

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

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

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

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

       wallclock
           Set the initial PTS using the current time. Default is 1.

       Examples

       Record a stream from default device:

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

   qtkit
       QTKit input device.

       The filename passed as input is parsed to contain either a device name or index.  The
       device index can also be given by using -video_device_index.  A given device index will
       override any given device name.  If the desired device consists of numbers only, use
       -video_device_index to identify it.  The default device will be chosen if an empty string
       or the device name "default" is given.  The available devices can be enumerated by using
       -list_devices.

               ffmpeg -f qtkit -i "0" out.mpg

               ffmpeg -f qtkit -video_device_index 0 -i "" out.mpg

               ffmpeg -f qtkit -i "default" out.mpg

               ffmpeg -f qtkit -list_devices true -i ""

       Options

       frame_rate
           Set frame rate. Default is 30.

       list_devices
           If set to "true", print a list of devices and exit. Default is "false".

       video_device_index
           Select the video device by index for devices with the same name (starts at 0).

   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 ffmpeg use the command:

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

       Options

       sample_rate
           Set the sample rate in Hz. Default is 48000.

       channels
           Set the number of channels. Default is 2.

   video4linux2, v4l2
       Video4Linux2 input video device.

       "v4l2" can be used as alias for "video4linux2".

       If FFmpeg is built with v4l-utils support (by using the "--enable-libv4l2" configure
       option), it is possible to use it with the "-use_libv4l2" input device option.

       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.

       Video4Linux2 devices usually support a limited set of widthxheight sizes and frame rates.
       You can check which are supported using -list_formats all for Video4Linux2 devices.  Some
       devices, like TV cards, support one or more standards. It is possible to list all the
       supported standards using -list_standards all.

       The time base for the timestamps is 1 microsecond. Depending on the kernel version and
       configuration, the timestamps may be derived from the real time clock (origin at the Unix
       Epoch) or the monotonic clock (origin usually at boot time, unaffected by NTP or manual
       changes to the clock). The -timestamps abs or -ts abs option can be used to force
       conversion into the real time clock.

       Some usage examples of the video4linux2 device with ffmpeg and ffplay:

       ·   List supported formats for a video4linux2 device:

                   ffplay -f video4linux2 -list_formats all /dev/video0

       ·   Grab and show the input of a video4linux2 device:

                   ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0

       ·   Grab and record the input of a video4linux2 device, leave the frame rate and size as
           previously set:

                   ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg

       For more information about Video4Linux, check <http://linuxtv.org/>.

       Options

       standard
           Set the standard. Must be the name of a supported standard. To get a list of the
           supported standards, use the list_standards option.

       channel
           Set the input channel number. Default to -1, which means using the previously selected
           channel.

       video_size
           Set the video frame size. The argument must be a string in the form WIDTHxHEIGHT or a
           valid size abbreviation.

       pixel_format
           Select the pixel format (only valid for raw video input).

       input_format
           Set the preferred pixel format (for raw video) or a codec name.  This option allows
           one to select the input format, when several are available.

       framerate
           Set the preferred video frame rate.

       list_formats
           List available formats (supported pixel formats, codecs, and frame sizes) and exit.

           Available values are:

           all Show all available (compressed and non-compressed) formats.

           raw Show only raw video (non-compressed) formats.

           compressed
               Show only compressed formats.

       list_standards
           List supported standards and exit.

           Available values are:

           all Show all supported standards.

       timestamps, ts
           Set type of timestamps for grabbed frames.

           Available values are:

           default
               Use timestamps from the kernel.

           abs Use absolute timestamps (wall clock).

           mono2abs
               Force conversion from monotonic to absolute timestamps.

           Default value is "default".

       use_libv4l2
           Use libv4l2 (v4l-utils) conversion functions. Default is 0.

   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.

       Options

       video_size
           Set the video frame size.

       framerate
           Set the grabbing frame rate. Default value is "ntsc", corresponding to a frame rate of
           "30000/1001".

   x11grab
       X11 video input device.

       To enable this input device during configuration you need libxcb installed on your system.
       It will be automatically detected during configuration.

       This device allows one 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 omitted, 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 xdpyinfo 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 ffmpeg:

               ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg

       Grab at position "10,20":

               ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg

       Options

       draw_mouse
           Specify whether to draw the mouse pointer. A value of 0 specifies not to draw the
           pointer. Default value is 1.

       follow_mouse
           Make the grabbed area follow the mouse. The argument can be "centered" or a number of
           pixels 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:

                   ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg

           To follow only when the mouse pointer reaches within 100 pixels to edge:

                   ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg

       framerate
           Set the grabbing frame rate. Default value is "ntsc", corresponding to a frame rate of
           "30000/1001".

       show_region
           Show grabbed region on screen.

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

       region_border
           Set the region border thickness if -show_region 1 is used.  Range is 1 to 128 and
           default is 3 (XCB-based x11grab only).

           For example:

                   ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg

           With follow_mouse:

                   ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg

       video_size
           Set the video frame size. Default value is "vga".

       grab_x
       grab_y
           Set the grabbing region coordinates. They are expressed as offset from the top left
           corner of the X11 window and correspond to the x_offset and y_offset parameters in the
           device name. The default value for both options is 0.

OUTPUT DEVICES

       Output devices are configured elements in FFmpeg that can write multimedia data to an
       output device attached to your system.

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

       You can disable all the output devices using the configure option "--disable-outdevs", and
       selectively enable an output device using the option "--enable-outdev=OUTDEV", or you can
       disable a particular input device using the option "--disable-outdev=OUTDEV".

       The option "-devices" of the ff* tools will display the list of enabled output devices.

       A description of the currently available output devices follows.

   alsa
       ALSA (Advanced Linux Sound Architecture) output device.

       Examples

       ·   Play a file on default ALSA device:

                   ffmpeg -i INPUT -f alsa default

       ·   Play a file on soundcard 1, audio device 7:

                   ffmpeg -i INPUT -f alsa hw:1,7

   caca
       CACA output device.

       This output device allows one to show a video stream in CACA window.  Only one CACA window
       is allowed per application, so you can have only one instance of this output device in an
       application.

       To enable this output device you need to configure FFmpeg with "--enable-libcaca".
       libcaca is a graphics library that outputs text instead of pixels.

       For more information about libcaca, check: <http://caca.zoy.org/wiki/libcaca>

       Options

       window_title
           Set the CACA window title, if not specified default to the filename specified for the
           output device.

       window_size
           Set the CACA window size, can be a string of the form widthxheight or a video size
           abbreviation.  If not specified it defaults to the size of the input video.

       driver
           Set display driver.

       algorithm
           Set dithering algorithm. Dithering is necessary because the picture being rendered has
           usually far more colours than the available palette.  The accepted values are listed
           with "-list_dither algorithms".

       antialias
           Set antialias method. Antialiasing smoothens the rendered image and avoids the
           commonly seen staircase effect.  The accepted values are listed with "-list_dither
           antialiases".

       charset
           Set which characters are going to be used when rendering text.  The accepted values
           are listed with "-list_dither charsets".

       color
           Set color to be used when rendering text.  The accepted values are listed with
           "-list_dither colors".

       list_drivers
           If set to true, print a list of available drivers and exit.

       list_dither
           List available dither options related to the argument.  The argument must be one of
           "algorithms", "antialiases", "charsets", "colors".

       Examples

       ·   The following command shows the ffmpeg output is an CACA window, forcing its size to
           80x25:

                   ffmpeg -i INPUT -vcodec rawvideo -pix_fmt rgb24 -window_size 80x25 -f caca -

       ·   Show the list of available drivers and exit:

                   ffmpeg -i INPUT -pix_fmt rgb24 -f caca -list_drivers true -

       ·   Show the list of available dither colors and exit:

                   ffmpeg -i INPUT -pix_fmt rgb24 -f caca -list_dither colors -

   decklink
       The decklink output device provides playback capabilities for Blackmagic DeckLink devices.

       To enable this output device, you need the Blackmagic DeckLink SDK and you need to
       configure with the appropriate "--extra-cflags" and "--extra-ldflags".  On Windows, you
       need to run the IDL files through widl.

       DeckLink is very picky about the formats it supports. Pixel format is always uyvy422,
       framerate, field order and video size must be determined for your device with
       -list_formats 1. Audio sample rate is always 48 kHz.

       Options

       list_devices
           If set to true, print a list of devices and exit.  Defaults to false.

       list_formats
           If set to true, print a list of supported formats and exit.  Defaults to false.

       preroll
           Amount of time to preroll video in seconds.  Defaults to 0.5.

       Examples

       ·   List output devices:

                   ffmpeg -i test.avi -f decklink -list_devices 1 dummy

       ·   List supported formats:

                   ffmpeg -i test.avi -f decklink -list_formats 1 'DeckLink Mini Monitor'

       ·   Play video clip:

                   ffmpeg -i test.avi -f decklink -pix_fmt uyvy422 'DeckLink Mini Monitor'

       ·   Play video clip with non-standard framerate or video size:

                   ffmpeg -i test.avi -f decklink -pix_fmt uyvy422 -s 720x486 -r 24000/1001 'DeckLink Mini Monitor'

   fbdev
       Linux framebuffer output 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.

       Options

       xoffset
       yoffset
           Set x/y coordinate of top left corner. Default is 0.

       Examples

       Play a file on framebuffer device /dev/fb0.  Required pixel format depends on current
       framebuffer settings.

               ffmpeg -re -i INPUT -vcodec rawvideo -pix_fmt bgra -f fbdev /dev/fb0

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

   opengl
       OpenGL output device.

       To enable this output device you need to configure FFmpeg with "--enable-opengl".

       This output device allows one to render to OpenGL context.  Context may be provided by
       application or default SDL window is created.

       When device renders to external context, application must implement handlers for following
       messages: "AV_DEV_TO_APP_CREATE_WINDOW_BUFFER" - create OpenGL context on current thread.
       "AV_DEV_TO_APP_PREPARE_WINDOW_BUFFER" - make OpenGL context current.
       "AV_DEV_TO_APP_DISPLAY_WINDOW_BUFFER" - swap buffers.
       "AV_DEV_TO_APP_DESTROY_WINDOW_BUFFER" - destroy OpenGL context.  Application is also
       required to inform a device about current resolution by sending
       "AV_APP_TO_DEV_WINDOW_SIZE" message.

       Options

       background
           Set background color. Black is a default.

       no_window
           Disables default SDL window when set to non-zero value.  Application must provide
           OpenGL context and both "window_size_cb" and "window_swap_buffers_cb" callbacks when
           set.

       window_title
           Set the SDL window title, if not specified default to the filename specified for the
           output device.  Ignored when no_window is set.

       window_size
           Set preferred window size, can be a string of the form widthxheight or a video size
           abbreviation.  If not specified it defaults to the size of the input video, downscaled
           according to the aspect ratio.  Mostly usable when no_window is not set.

       Examples

       Play a file on SDL window using OpenGL rendering:

               ffmpeg  -i INPUT -f opengl "window title"

   oss
       OSS (Open Sound System) output device.

   pulse
       PulseAudio output device.

       To enable this output device you need to configure FFmpeg with "--enable-libpulse".

       More information about PulseAudio can be found on <http://www.pulseaudio.org>

       Options

       server
           Connect to a specific PulseAudio server, specified by an IP address.  Default server
           is used when not provided.

       name
           Specify the application name PulseAudio will use when showing active clients, by
           default it is the "LIBAVFORMAT_IDENT" string.

       stream_name
           Specify the stream name PulseAudio will use when showing active streams, by default it
           is set to the specified output name.

       device
           Specify the device to use. Default device is used when not provided.  List of output
           devices can be obtained with command pactl list sinks.

       buffer_size
       buffer_duration
           Control the size and duration of the PulseAudio buffer. A small buffer gives more
           control, but requires more frequent updates.

           buffer_size specifies size in bytes while buffer_duration specifies duration in
           milliseconds.

           When both options are provided then the highest value is used (duration is
           recalculated to bytes using stream parameters). If they are set to 0 (which is
           default), the device will use the default PulseAudio duration value. By default
           PulseAudio set buffer duration to around 2 seconds.

       prebuf
           Specify pre-buffering size in bytes. The server does not start with playback before at
           least prebuf bytes are available in the buffer. By default this option is initialized
           to the same value as buffer_size or buffer_duration (whichever is bigger).

       minreq
           Specify minimum request size in bytes. The server does not request less than minreq
           bytes from the client, instead waits until the buffer is free enough to request more
           bytes at once. It is recommended to not set this option, which will initialize this to
           a value that is deemed sensible by the server.

       Examples

       Play a file on default device on default server:

               ffmpeg  -i INPUT -f pulse "stream name"

   sdl
       SDL (Simple DirectMedia Layer) output device.

       This output device allows one to show a video stream in an SDL window. Only one SDL window
       is allowed per application, so you can have only one instance of this output device in an
       application.

       To enable this output device you need libsdl installed on your system when configuring
       your build.

       For more information about SDL, check: <http://www.libsdl.org/>

       Options

       window_title
           Set the SDL window title, if not specified default to the filename specified for the
           output device.

       icon_title
           Set the name of the iconified SDL window, if not specified it is set to the same value
           of window_title.

       window_size
           Set the SDL window size, can be a string of the form widthxheight or a video size
           abbreviation.  If not specified it defaults to the size of the input video, downscaled
           according to the aspect ratio.

       window_fullscreen
           Set fullscreen mode when non-zero value is provided.  Default value is zero.

       Interactive commands

       The window created by the device can be controlled through the following interactive
       commands.

       q, ESC
           Quit the device immediately.

       Examples

       The following command shows the ffmpeg output is an SDL window, forcing its size to the
       qcif format:

               ffmpeg -i INPUT -vcodec rawvideo -pix_fmt yuv420p -window_size qcif -f sdl "SDL output"

   sndio
       sndio audio output device.

   xv
       XV (XVideo) output device.

       This output device allows one to show a video stream in a X Window System window.

       Options

       display_name
           Specify the hardware display name, which determines the display and communications
           domain to be used.

           The display name or DISPLAY environment variable can be a string in the format
           hostname[:number[.screen_number]].

           hostname specifies the name of the host machine on which the display is physically
           attached. number specifies the number of the display server on that host machine.
           screen_number specifies the screen to be used on that server.

           If unspecified, it defaults to the value of the DISPLAY environment variable.

           For example, "dual-headed:0.1" would specify screen 1 of display 0 on the machine
           named ``dual-headed''.

           Check the X11 specification for more detailed information about the display name
           format.

       window_id
           When set to non-zero value then device doesn't create new window, but uses existing
           one with provided window_id. By default this options is set to zero and device creates
           its own window.

       window_size
           Set the created window size, can be a string of the form widthxheight or a video size
           abbreviation. If not specified it defaults to the size of the input video.  Ignored
           when window_id is set.

       window_x
       window_y
           Set the X and Y window offsets for the created window. They are both set to 0 by
           default. The values may be ignored by the window manager.  Ignored when window_id is
           set.

       window_title
           Set the window title, if not specified default to the filename specified for the
           output device. Ignored when window_id is set.

       For more information about XVideo see <http://www.x.org/>.

       Examples

       ·   Decode, display and encode video input with ffmpeg at the same time:

                   ffmpeg -i INPUT OUTPUT -f xv display

       ·   Decode and display the input video to multiple X11 windows:

                   ffmpeg -i INPUT -f xv normal -vf negate -f xv negated

SEE ALSO

       ffmpeg(1), ffplay(1), ffprobe(1), ffserver(1), libavdevice(3)

AUTHORS

       The FFmpeg developers.

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

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

                                                                                FFMPEG-DEVICES(1)