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ffmpeg-devices(1)                                            ffmpeg-devices(1)




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.

   android_camera
       Android camera input device.

       This input devices uses the Android Camera2 NDK API which is available
       on devices with API level 24+. The availability of android_camera is
       autodetected during configuration.

       This device allows capturing from all cameras on an Android device,
       which are integrated into the Camera2 NDK API.

       The available cameras are enumerated internally and can be selected
       with the camera_index parameter. The input file string is discarded.

       Generally the back facing camera has index 0 while the front facing
       camera has index 1.

       Options

       video_size
           Set the video size given as a string such as 640x480 or hd720.
           Falls back to the first available configuration reported by Android
           if requested video size is not available or by default.

       framerate
           Set the video framerate.  Falls back to the first available
           configuration reported by Android if requested framerate is not
           available or by default (-1).

       camera_index
           Set the index of the camera to use. Default is 0.

       input_queue_size
           Set the maximum number of frames to buffer. Default is 5.

   avfoundation
       AVFoundation input device.

       AVFoundation is the currently recommended framework by Apple for
       streamgrabbing on OSX >= 10.7 as well as on iOS.

       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.

       -capture_raw_data
           Capture the raw device data. Default is 0.  Using this option may
           result in receiving the underlying data delivered to the
           AVFoundation framework. E.g. for muxed devices that sends raw DV
           data to the framework (like tape-based camcorders), setting this
           option to false results in extracted video frames captured in the
           designated pixel format only. Setting this option to true results
           in receiving the raw DV stream untouched.

       Examples

       o   Print the list of AVFoundation supported devices and exit:

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

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

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

       o   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

       o   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

       o   Record raw DV data from a suitable input device and write the
           output into out.dv:

                   $ ffmpeg -f avfoundation -capture_raw_data true -i "zr100:none" out.dv

   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 of
       the input can be set with raw_format.  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. This option is deprecated, please use the "-sources" option
           of ffmpeg to list the available input devices.

       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).  Default behavior is autodetection of the input video
           format, if the hardware supports it.

       raw_format
           Set the pixel format of the captured video.  Available values are:

           auto
               This is the default which means 8-bit YUV 422 or 8-bit ARGB if
               format autodetection is used, 8-bit YUV 422 otherwise.

           uyvy422
               8-bit YUV 422.

           yuv422p10
               10-bit YUV 422.

           argb
               8-bit RGB.

           bgra
               8-bit RGB.

           rgb10
               10-bit RGB.

       teletext_lines
           If set to nonzero, an additional teletext stream will be captured
           from the vertical ancillary data. Both SD PAL (576i) and HD (1080i
           or 1080p) sources are supported. In case of HD sources, OP47
           packets are decoded.

           This option is a bitmask of the SD PAL VBI lines captured,
           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.

           For SD sources, ffmpeg needs to be compiled with
           "--enable-libzvbi". For HD sources, on older (pre-4K) DeckLink card
           models you have to capture in 10 bit mode.

       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.

       timecode_format
           Timecode type to include in the frame and video stream metadata.
           Must be none, rp188vitc, rp188vitc2, rp188ltc, rp188hfr, rp188any,
           vitc, vitc2, or serial.  Defaults to none (not included).

           In order to properly support 50/60 fps timecodes, the ordering of
           the queried timecode types for rp188any is HFR, VITC1, VITC2 and
           LTC for >30 fps content. Note that this is slightly different to
           the ordering used by the DeckLink API, which is HFR, VITC1, LTC,
           VITC2.

       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, wallclock or abs_wallclock.  Defaults to video.

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

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

       queue_size
           Sets maximum input buffer size in bytes. If the buffering reaches
           this value, incoming frames will be dropped.  Defaults to
           1073741824.

       audio_depth
           Sets the audio sample bit depth. Must be 16 or 32.  Defaults to 16.

       decklink_copyts
           If set to true, timestamps are forwarded as they are without
           removing the initial offset.  Defaults to false.

       timestamp_align
           Capture start time alignment in seconds. If set to nonzero, input
           frames are dropped till the system timestamp aligns with configured
           value.  Alignment difference of up to one frame duration is
           tolerated.  This is useful for maintaining input synchronization
           across N different hardware devices deployed for 'N-way'
           redundancy. The system time of different hardware devices should be
           synchronized with protocols such as NTP or PTP, before using this
           option.  Note that this method is not foolproof. In some border
           cases input synchronization may not happen due to thread scheduling
           jitters in the OS.  Either sync could go wrong by 1 frame or in a
           rarer case timestamp_align seconds.  Defaults to 0.

       wait_for_tc (bool)
           Drop frames till a frame with timecode is received. Sometimes
           serial timecode isn't received with the first input frame. If that
           happens, the stored stream timecode will be inaccurate. If this
           option is set to true, input frames are dropped till a frame with
           timecode is received.  Option timecode_format must be specified.
           Defaults to false.

       enable_klv(bool)
           If set to true, extracts KLV data from VANC and outputs KLV
           packets.  KLV VANC packets are joined based on MID and PSC fields
           and aggregated into one KLV packet.  Defaults to false.

       Examples

       o   List input devices:

                   ffmpeg -sources decklink

       o   List supported formats:

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

       o   Capture video clip at 1080i50:

                   ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -c:a copy -c:v copy output.avi

       o   Capture video clip at 1080i50 10 bit:

                   ffmpeg -raw_format yuv422p10 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi

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

                   ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v 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

       o   Print the list of DirectShow supported devices and exit:

                   $ ffmpeg -list_devices true -f dshow -i dummy

       o   Open video device Camera:

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

       o   Open second video device with name Camera:

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

       o   Open video device Camera and audio device Microphone:

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

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

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

       o   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"

       o   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"

   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

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

                   ffplay -f iec61883 -i auto

       o   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 -dvbuffer 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.

   kmsgrab
       KMS video input device.

       Captures the KMS scanout framebuffer associated with a specified CRTC
       or plane as a DRM object that can be passed to other hardware
       functions.

       Requires either DRM master or CAP_SYS_ADMIN to run.

       If you don't understand what all of that means, you probably don't want
       this.  Look at x11grab instead.

       Options

       device
           DRM device to capture on.  Defaults to /dev/dri/card0.

       format
           Pixel format of the framebuffer.  This can be autodetected if you
           are running Linux 5.7 or later, but needs to be provided for
           earlier versions.  Defaults to bgr0, which is the most common
           format used by the Linux console and Xorg X server.

       format_modifier
           Format modifier to signal on output frames.  This is necessary to
           import correctly into some APIs.  It can be autodetected if you are
           running Linux 5.7 or later, but will need to be provided explicitly
           when needed in earlier versions.  See the libdrm documentation for
           possible values.

       crtc_id
           KMS CRTC ID to define the capture source.  The first active plane
           on the given CRTC will be used.

       plane_id
           KMS plane ID to define the capture source.  Defaults to the first
           active plane found if neither crtc_id nor plane_id are specified.

       framerate
           Framerate to capture at.  This is not synchronised to any page
           flipping or framebuffer changes - it just defines the interval at
           which the framebuffer is sampled.  Sampling faster than the
           framebuffer update rate will generate independent frames with the
           same content.  Defaults to 30.

       Examples

       o   Capture from the first active plane, download the result to normal
           frames and encode.  This will only work if the framebuffer is both
           linear and mappable - if not, the result may be scrambled or fail
           to download.

                   ffmpeg -f kmsgrab -i - -vf 'hwdownload,format=bgr0' output.mp4

       o   Capture from CRTC ID 42 at 60fps, map the result to VAAPI, convert
           to NV12 and encode as H.264.

                   ffmpeg -crtc_id 42 -framerate 60 -f kmsgrab -i - -vf 'hwmap=derive_device=vaapi,scale_vaapi=w=1920:h=1080:format=nv12' -c:v h264_vaapi output.mp4

       o   To capture only part of a plane the output can be cropped - this
           can be used to capture a single window, as long as it has a known
           absolute position and size.  For example, to capture and encode the
           middle quarter of a 1920x1080 plane:

                   ffmpeg -f kmsgrab -i - -vf 'hwmap=derive_device=vaapi,crop=960:540:480:270,scale_vaapi=960:540:nv12' -c:v h264_vaapi output.mp4

   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

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

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

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

                   ffplay -f lavfi color=c=pink

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

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

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

                   ffplay -f lavfi "amovie=test.wav"

       o   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]"

       o   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".

       Options

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

       pixel_format
           Select the pixel format. Default is "uyvy422".

       video_size
           Set the video size given as a string such as "640x480" or "hd720".
           Default is "qvga".

   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

   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:

       o   List supported formats for a video4linux2 device:

                   ffplay -f video4linux2 -list_formats all /dev/video0

       o   Grab and show the input of a video4linux2 device:

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

       o   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

       select_region
           Specify whether to select the grabbing area graphically using the
           pointer.  A value of 1 prompts the user to select the grabbing area
           graphically by clicking and dragging. A single click with no
           dragging will select the whole screen. A region with zero width or
           height will also select the whole screen. This option overwrites
           the video_size, grab_x, and grab_y options. Default value is 0.

       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

       window_id
           Grab this window, instead of the whole screen. Default value is 0,
           which maps to the whole screen (root window).

           The id of a window can be found using the xwininfo program,
           possibly with options -tree and -root.

           If the window is later enlarged, the new area is not recorded.
           Video ends when the window is closed, unmapped (i.e., iconified) or
           shrunk beyond the video size (which defaults to the initial window
           size).

           This option disables options follow_mouse and select_region.

       video_size
           Set the video frame size. Default is the full desktop or window.

       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

       o   Play a file on default ALSA device:

                   ffmpeg -i INPUT -f alsa default

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

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

   AudioToolbox
       AudioToolbox output device.

       Allows native output to CoreAudio devices on OSX.

       The output filename can be empty (or "-") to refer to the default
       system output device or a number that refers to the device index as
       shown using: "-list_devices true".

       Alternatively, the audio input device can be chosen by index using the

           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, UIDs and corresponding indices.

       Options

       AudioToolbox supports the following options:

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

       Examples

       o   Print the list of supported devices and output a sine wave to the
           default device:

                   $ ffmpeg -f lavfi -i sine=r=44100 -f audiotoolbox -list_devices true -

       o   Output a sine wave to the device with the index 2, overriding any
           output filename:

                   $ ffmpeg -f lavfi -i sine=r=44100 -f audiotoolbox -audio_device_index 2 -

   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

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

                   ffmpeg -i INPUT -c:v rawvideo -pix_fmt rgb24 -window_size 80x25 -f caca -

       o   Show the list of available drivers and exit:

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

       o   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. This option is deprecated, please use the "-sinks" option of
           ffmpeg to list the available output devices.

       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.

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

       timing_offset
           Sets the genlock timing pixel offset on the used output.  Defaults
           to unset.

       Examples

       o   List output devices:

                   ffmpeg -sinks decklink

       o   List supported formats:

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

       o   Play video clip:

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

       o   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 -c:v 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.

       "sdl2" can be used as alias for "sdl".

       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_x
       window_y
           Set the position of the window on the screen.

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

       window_enable_quit
           Enable quit action (using window button or keyboard key) when non-
           zero value is provided.  Default value is 1 (enable quit action)

       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 -c:v rawvideo -pix_fmt yuv420p -window_size qcif -f sdl "SDL output"

   sndio
       sndio audio output device.

   v4l2
       Video4Linux2 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

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

                   ffmpeg -i INPUT OUTPUT -f xv display

       o   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), 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)

ffmpeg 4.4 - Generated Fri Apr 23 09:25:37 CDT 2021
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