2 @c man begin INPUT DEVICES
4 Input devices are configured elements in FFmpeg which allow to access
5 the data coming from a multimedia device attached to your system.
7 When you configure your FFmpeg build, all the supported input devices
8 are enabled by default. You can list all available ones using the
9 configure option "--list-indevs".
11 You can disable all the input devices using the configure option
12 "--disable-indevs", and selectively enable an input device using the
13 option "--enable-indev=@var{INDEV}", or you can disable a particular
14 input device using the option "--disable-indev=@var{INDEV}".
16 The option "-devices" of the ff* tools will display the list of
17 supported input devices.
19 A description of the currently available input devices follows.
23 ALSA (Advanced Linux Sound Architecture) input device.
25 To enable this input device during configuration you need libasound
26 installed on your system.
28 This device allows capturing from an ALSA device. The name of the
29 device to capture has to be an ALSA card identifier.
31 An ALSA identifier has the syntax:
33 hw:@var{CARD}[,@var{DEV}[,@var{SUBDEV}]]
36 where the @var{DEV} and @var{SUBDEV} components are optional.
38 The three arguments (in order: @var{CARD},@var{DEV},@var{SUBDEV})
39 specify card number or identifier, device number and subdevice number
42 To see the list of cards currently recognized by your system check the
43 files @file{/proc/asound/cards} and @file{/proc/asound/devices}.
45 For example to capture with @command{ffmpeg} from an ALSA device with
46 card id 0, you may run the command:
48 ffmpeg -f alsa -i hw:0 alsaout.wav
51 For more information see:
52 @url{http://www.alsa-project.org/alsa-doc/alsa-lib/pcm.html}
56 AVFoundation input device.
58 AVFoundation is the currently recommended framework by Apple for streamgrabbing on OSX >= 10.7 as well as on iOS.
59 The older QTKit framework has been marked deprecated since OSX version 10.7.
61 The input filename has to be given in the following syntax:
63 -i "[[VIDEO]:[AUDIO]]"
65 The first entry selects the video input while the latter selects the audio input.
66 The stream has to be specified by the device name or the device index as shown by the device list.
67 Alternatively, the video and/or audio input device can be chosen by index using the
69 -video_device_index <INDEX>
73 -audio_device_index <INDEX>
76 device name or index given in the input filename.
78 All available devices can be enumerated by using @option{-list_devices true}, listing
79 all device names and corresponding indices.
81 There are two device name aliases:
85 Select the AVFoundation default device of the corresponding type.
88 Do not record the corresponding media type.
89 This is equivalent to specifying an empty device name or index.
95 AVFoundation supports the following options:
99 @item -list_devices <TRUE|FALSE>
100 If set to true, a list of all available input devices is given showing all
101 device names and indices.
103 @item -video_device_index <INDEX>
104 Specify the video device by its index. Overrides anything given in the input filename.
106 @item -audio_device_index <INDEX>
107 Specify the audio device by its index. Overrides anything given in the input filename.
109 @item -pixel_format <FORMAT>
110 Request the video device to use a specific pixel format.
111 If the specified format is not supported, a list of available formats is given
112 und the first one in this list is used instead. Available pixel formats are:
113 @code{monob, rgb555be, rgb555le, rgb565be, rgb565le, rgb24, bgr24, 0rgb, bgr0, 0bgr, rgb0,
114 bgr48be, uyvy422, yuva444p, yuva444p16le, yuv444p, yuv422p16, yuv422p10, yuv444p10,
115 yuv420p, nv12, yuyv422, gray}
124 Print the list of AVFoundation supported devices and exit:
126 $ ffmpeg -f avfoundation -list_devices true -i ""
130 Record video from video device 0 and audio from audio device 0 into out.avi:
132 $ ffmpeg -f avfoundation -i "0:0" out.avi
136 Record video from video device 2 and audio from audio device 1 into out.avi:
138 $ ffmpeg -f avfoundation -video_device_index 2 -i ":1" out.avi
142 Record video from the system default video device using the pixel format bgr0 and do not record any audio into out.avi:
144 $ ffmpeg -f avfoundation -pixel_format bgr0 -i "default:none" out.avi
151 BSD video input device.
155 Windows DirectShow input device.
157 DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
158 Currently only audio and video devices are supported.
160 Multiple devices may be opened as separate inputs, but they may also be
161 opened on the same input, which should improve synchronism between them.
163 The input name should be in the format:
166 @var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
169 where @var{TYPE} can be either @var{audio} or @var{video},
170 and @var{NAME} is the device's name.
174 If no options are specified, the device's defaults are used.
175 If the device does not support the requested options, it will
181 Set the video size in the captured video.
184 Set the frame rate in the captured video.
187 Set the sample rate (in Hz) of the captured audio.
190 Set the sample size (in bits) of the captured audio.
193 Set the number of channels in the captured audio.
196 If set to @option{true}, print a list of devices and exit.
199 If set to @option{true}, print a list of selected device's options
202 @item video_device_number
203 Set video device number for devices with same name (starts at 0,
206 @item audio_device_number
207 Set audio device number for devices with same name (starts at 0,
211 Select pixel format to be used by DirectShow. This may only be set when
212 the video codec is not set or set to rawvideo.
214 @item audio_buffer_size
215 Set audio device buffer size in milliseconds (which can directly
216 impact latency, depending on the device).
217 Defaults to using the audio device's
218 default buffer size (typically some multiple of 500ms).
219 Setting this value too low can degrade performance.
221 @url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
230 Print the list of DirectShow supported devices and exit:
232 $ ffmpeg -list_devices true -f dshow -i dummy
236 Open video device @var{Camera}:
238 $ ffmpeg -f dshow -i video="Camera"
242 Open second video device with name @var{Camera}:
244 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
248 Open video device @var{Camera} and audio device @var{Microphone}:
250 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
254 Print the list of supported options in selected device and exit:
256 $ ffmpeg -list_options true -f dshow -i video="Camera"
263 Linux DV 1394 input device.
267 Linux framebuffer input device.
269 The Linux framebuffer is a graphic hardware-independent abstraction
270 layer to show graphics on a computer monitor, typically on the
271 console. It is accessed through a file device node, usually
274 For more detailed information read the file
275 Documentation/fb/framebuffer.txt included in the Linux source tree.
277 To record from the framebuffer device @file{/dev/fb0} with
280 ffmpeg -f fbdev -r 10 -i /dev/fb0 out.avi
283 You can take a single screenshot image with the command:
285 ffmpeg -f fbdev -frames:v 1 -r 1 -i /dev/fb0 screenshot.jpeg
288 See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
292 Win32 GDI-based screen capture device.
294 This device allows you to capture a region of the display on Windows.
296 There are two options for the input filename:
302 title=@var{window_title}
305 The first option will capture the entire desktop, or a fixed region of the
306 desktop. The second option will instead capture the contents of a single
307 window, regardless of its position on the screen.
309 For example, to grab the entire desktop using @command{ffmpeg}:
311 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
314 Grab a 640x480 region at position @code{10,20}:
316 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
319 Grab the contents of the window named "Calculator"
321 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
328 Specify whether to draw the mouse pointer. Use the value @code{0} to
329 not draw the pointer. Default value is @code{1}.
332 Set the grabbing frame rate. Default value is @code{ntsc},
333 corresponding to a frame rate of @code{30000/1001}.
336 Show grabbed region on screen.
338 If @var{show_region} is specified with @code{1}, then the grabbing
339 region will be indicated on screen. With this option, it is easy to
340 know what is being grabbed if only a portion of the screen is grabbed.
342 Note that @var{show_region} is incompatible with grabbing the contents
347 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
351 Set the video frame size. The default is to capture the full screen if @file{desktop} is selected, or the full window size if @file{title=@var{window_title}} is selected.
354 When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
356 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 @var{offset_x} value to move the region to that monitor.
359 When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
361 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 @var{offset_y} value to move the region to that monitor.
367 FireWire DV/HDV input device using libiec61883.
369 To enable this input device, you need libiec61883, libraw1394 and
370 libavc1394 installed on your system. Use the configure option
371 @code{--enable-libiec61883} to compile with the device enabled.
373 The iec61883 capture device supports capturing from a video device
374 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
375 FireWire stack (juju). This is the default DV/HDV input method in Linux
376 Kernel 2.6.37 and later, since the old FireWire stack was removed.
378 Specify the FireWire port to be used as input file, or "auto"
379 to choose the first port connected.
386 Override autodetection of DV/HDV. This should only be used if auto
387 detection does not work, or if usage of a different device type
388 should be prohibited. Treating a DV device as HDV (or vice versa) will
389 not work and result in undefined behavior.
390 The values @option{auto}, @option{dv} and @option{hdv} are supported.
393 Set maxiumum size of buffer for incoming data, in frames. For DV, this
394 is an exact value. For HDV, it is not frame exact, since HDV does
395 not have a fixed frame size.
398 Select the capture device by specifying it's GUID. Capturing will only
399 be performed from the specified device and fails if no device with the
400 given GUID is found. This is useful to select the input if multiple
401 devices are connected at the same time.
402 Look at /sys/bus/firewire/devices to find out the GUIDs.
411 Grab and show the input of a FireWire DV/HDV device.
413 ffplay -f iec61883 -i auto
417 Grab and record the input of a FireWire DV/HDV device,
418 using a packet buffer of 100000 packets if the source is HDV.
420 ffmpeg -f iec61883 -i auto -hdvbuffer 100000 out.mpg
429 To enable this input device during configuration you need libjack
430 installed on your system.
432 A JACK input device creates one or more JACK writable clients, one for
433 each audio channel, with name @var{client_name}:input_@var{N}, where
434 @var{client_name} is the name provided by the application, and @var{N}
435 is a number which identifies the channel.
436 Each writable client will send the acquired data to the FFmpeg input
439 Once you have created one or more JACK readable clients, you need to
440 connect them to one or more JACK writable clients.
442 To connect or disconnect JACK clients you can use the @command{jack_connect}
443 and @command{jack_disconnect} programs, or do it through a graphical interface,
444 for example with @command{qjackctl}.
446 To list the JACK clients and their properties you can invoke the command
449 Follows an example which shows how to capture a JACK readable client
450 with @command{ffmpeg}.
452 # Create a JACK writable client with name "ffmpeg".
453 $ ffmpeg -f jack -i ffmpeg -y out.wav
455 # Start the sample jack_metro readable client.
456 $ jack_metro -b 120 -d 0.2 -f 4000
458 # List the current JACK clients.
467 # Connect metro to the ffmpeg writable client.
468 $ jack_connect metro:120_bpm ffmpeg:input_1
471 For more information read:
472 @url{http://jackaudio.org/}
476 Libavfilter input virtual device.
478 This input device reads data from the open output pads of a libavfilter
481 For each filtergraph open output, the input device will create a
482 corresponding stream which is mapped to the generated output. Currently
483 only video data is supported. The filtergraph is specified through the
484 option @option{graph}.
491 Specify the filtergraph to use as input. Each video open output must be
492 labelled by a unique string of the form "out@var{N}", where @var{N} is a
493 number starting from 0 corresponding to the mapped input stream
494 generated by the device.
495 The first unlabelled output is automatically assigned to the "out0"
496 label, but all the others need to be specified explicitly.
498 If not specified defaults to the filename specified for the input
502 Set the filename of the filtergraph to be read and sent to the other
503 filters. Syntax of the filtergraph is the same as the one specified by
504 the option @var{graph}.
512 Create a color video stream and play it back with @command{ffplay}:
514 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
518 As the previous example, but use filename for specifying the graph
519 description, and omit the "out0" label:
521 ffplay -f lavfi color=c=pink
525 Create three different video test filtered sources and play them:
527 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
531 Read an audio stream from a file using the amovie source and play it
532 back with @command{ffplay}:
534 ffplay -f lavfi "amovie=test.wav"
538 Read an audio stream and a video stream and play it back with
541 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
548 Audio-CD input device based on cdio.
550 To enable this input device during configuration you need libcdio
551 installed on your system. Requires the configure option
552 @code{--enable-libcdio}.
554 This device allows playing and grabbing from an Audio-CD.
556 For example to copy with @command{ffmpeg} the entire Audio-CD in /dev/sr0,
557 you may run the command:
559 ffmpeg -f libcdio -i /dev/sr0 cd.wav
564 IIDC1394 input device, based on libdc1394 and libraw1394.
566 Requires the configure option @code{--enable-libdc1394}.
570 The OpenAL input device provides audio capture on all systems with a
571 working OpenAL 1.1 implementation.
573 To enable this input device during configuration, you need OpenAL
574 headers and libraries installed on your system, and need to configure
575 FFmpeg with @code{--enable-openal}.
577 OpenAL headers and libraries should be provided as part of your OpenAL
578 implementation, or as an additional download (an SDK). Depending on your
579 installation you may need to specify additional flags via the
580 @code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
581 system to locate the OpenAL headers and libraries.
583 An incomplete list of OpenAL implementations follows:
587 The official Windows implementation, providing hardware acceleration
588 with supported devices and software fallback.
589 See @url{http://openal.org/}.
591 Portable, open source (LGPL) software implementation. Includes
592 backends for the most common sound APIs on the Windows, Linux,
593 Solaris, and BSD operating systems.
594 See @url{http://kcat.strangesoft.net/openal.html}.
596 OpenAL is part of Core Audio, the official Mac OS X Audio interface.
597 See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
600 This device allows one to capture from an audio input device handled
603 You need to specify the name of the device to capture in the provided
604 filename. If the empty string is provided, the device will
605 automatically select the default device. You can get the list of the
606 supported devices by using the option @var{list_devices}.
613 Set the number of channels in the captured audio. Only the values
614 @option{1} (monaural) and @option{2} (stereo) are currently supported.
615 Defaults to @option{2}.
618 Set the sample size (in bits) of the captured audio. Only the values
619 @option{8} and @option{16} are currently supported. Defaults to
623 Set the sample rate (in Hz) of the captured audio.
624 Defaults to @option{44.1k}.
627 If set to @option{true}, print a list of devices and exit.
628 Defaults to @option{false}.
634 Print the list of OpenAL supported devices and exit:
636 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
639 Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
641 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
644 Capture from the default device (note the empty string '' as filename):
646 $ ffmpeg -f openal -i '' out.ogg
649 Capture from two devices simultaneously, writing to two different files,
650 within the same @command{ffmpeg} command:
652 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
654 Note: not all OpenAL implementations support multiple simultaneous capture -
655 try the latest OpenAL Soft if the above does not work.
659 Open Sound System input device.
661 The filename to provide to the input device is the device node
662 representing the OSS input device, and is usually set to
665 For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
668 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
671 For more information about OSS see:
672 @url{http://manuals.opensound.com/usersguide/dsp.html}
676 PulseAudio input device.
678 To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
680 The filename to provide to the input device is a source device or the
683 To list the PulseAudio source devices and their properties you can invoke
684 the command @command{pactl list sources}.
686 More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
691 Connect to a specific PulseAudio server, specified by an IP address.
692 Default server is used when not provided.
695 Specify the application name PulseAudio will use when showing active clients,
696 by default it is the @code{LIBAVFORMAT_IDENT} string.
699 Specify the stream name PulseAudio will use when showing active streams,
700 by default it is "record".
703 Specify the samplerate in Hz, by default 48kHz is used.
706 Specify the channels in use, by default 2 (stereo) is set.
709 Specify the number of bytes per frame, by default it is set to 1024.
712 Specify the minimal buffering fragment in PulseAudio, it will affect the
713 audio latency. By default it is unset.
717 Record a stream from default device:
719 ffmpeg -f pulse -i default /tmp/pulse.wav
726 The filename passed as input is parsed to contain either a device name or index.
727 The device index can also be given by using -video_device_index.
728 A given device index will override any given device name.
729 If the desired device consists of numbers only, use -video_device_index to identify it.
730 The default device will be chosen if an empty string or the device name "default" is given.
731 The available devices can be enumerated by using -list_devices.
734 ffmpeg -f qtkit -i "0" out.mpg
738 ffmpeg -f qtkit -video_device_index 0 -i "" out.mpg
742 ffmpeg -f qtkit -i "default" out.mpg
746 ffmpeg -f qtkit -list_devices true -i ""
753 To enable this input device during configuration you need libsndio
754 installed on your system.
756 The filename to provide to the input device is the device node
757 representing the sndio input device, and is usually set to
760 For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
763 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
766 @section video4linux2, v4l2
768 Video4Linux2 input video device.
770 "v4l2" can be used as alias for "video4linux2".
772 If FFmpeg is built with v4l-utils support (by using the
773 @code{--enable-libv4l2} configure option), it is possible to use it with the
774 @code{-use_libv4l2} input device option.
776 The name of the device to grab is a file device node, usually Linux
777 systems tend to automatically create such nodes when the device
778 (e.g. an USB webcam) is plugged into the system, and has a name of the
779 kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
782 Video4Linux2 devices usually support a limited set of
783 @var{width}x@var{height} sizes and frame rates. You can check which are
784 supported using @command{-list_formats all} for Video4Linux2 devices.
785 Some devices, like TV cards, support one or more standards. It is possible
786 to list all the supported standards using @command{-list_standards all}.
788 The time base for the timestamps is 1 microsecond. Depending on the kernel
789 version and configuration, the timestamps may be derived from the real time
790 clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
791 boot time, unaffected by NTP or manual changes to the clock). The
792 @option{-timestamps abs} or @option{-ts abs} option can be used to force
793 conversion into the real time clock.
795 Some usage examples of the video4linux2 device with @command{ffmpeg}
796 and @command{ffplay}:
799 Grab and show the input of a video4linux2 device:
801 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
805 Grab and record the input of a video4linux2 device, leave the
806 frame rate and size as previously set:
808 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
812 For more information about Video4Linux, check @url{http://linuxtv.org/}.
818 Set the standard. Must be the name of a supported standard. To get a
819 list of the supported standards, use the @option{list_standards}
823 Set the input channel number. Default to -1, which means using the
824 previously selected channel.
827 Set the video frame size. The argument must be a string in the form
828 @var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
831 Select the pixel format (only valid for raw video input).
834 Set the preferred pixel format (for raw video) or a codec name.
835 This option allows one to select the input format, when several are
839 Set the preferred video frame rate.
842 List available formats (supported pixel formats, codecs, and frame
845 Available values are:
848 Show all available (compressed and non-compressed) formats.
851 Show only raw video (non-compressed) formats.
854 Show only compressed formats.
858 List supported standards and exit.
860 Available values are:
863 Show all supported standards.
867 Set type of timestamps for grabbed frames.
869 Available values are:
872 Use timestamps from the kernel.
875 Use absolute timestamps (wall clock).
878 Force conversion from monotonic to absolute timestamps.
881 Default value is @code{default}.
886 VfW (Video for Windows) capture input device.
888 The filename passed as input is the capture driver number, ranging from
889 0 to 9. You may use "list" as filename to print a list of drivers. Any
890 other filename will be interpreted as device number 0.
894 X11 video input device.
896 Depends on X11, Xext, and Xfixes. Requires the configure option
897 @code{--enable-x11grab}.
899 This device allows one to capture a region of an X11 display.
901 The filename passed as input has the syntax:
903 [@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
906 @var{hostname}:@var{display_number}.@var{screen_number} specifies the
907 X11 display name of the screen to grab from. @var{hostname} can be
908 omitted, and defaults to "localhost". The environment variable
909 @env{DISPLAY} contains the default display name.
911 @var{x_offset} and @var{y_offset} specify the offsets of the grabbed
912 area with respect to the top-left border of the X11 screen. They
915 Check the X11 documentation (e.g. man X) for more detailed information.
917 Use the @command{dpyinfo} program for getting basic information about the
918 properties of your X11 display (e.g. grep for "name" or "dimensions").
920 For example to grab from @file{:0.0} using @command{ffmpeg}:
922 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
925 Grab at position @code{10,20}:
927 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
934 Specify whether to draw the mouse pointer. A value of @code{0} specify
935 not to draw the pointer. Default value is @code{1}.
938 Make the grabbed area follow the mouse. The argument can be
939 @code{centered} or a number of pixels @var{PIXELS}.
941 When it is specified with "centered", the grabbing region follows the mouse
942 pointer and keeps the pointer at the center of region; otherwise, the region
943 follows only when the mouse pointer reaches within @var{PIXELS} (greater than
944 zero) to the edge of region.
948 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
951 To follow only when the mouse pointer reaches within 100 pixels to edge:
953 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
957 Set the grabbing frame rate. Default value is @code{ntsc},
958 corresponding to a frame rate of @code{30000/1001}.
961 Show grabbed region on screen.
963 If @var{show_region} is specified with @code{1}, then the grabbing
964 region will be indicated on screen. With this option, it is easy to
965 know what is being grabbed if only a portion of the screen is grabbed.
969 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
972 With @var{follow_mouse}:
974 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
978 Set the video frame size. Default value is @code{vga}.
981 Use the MIT-SHM extension for shared memory. Default value is @code{1}.
982 It may be necessary to disable it for remote displays.
987 The decklink input device provides capture capabilities for Blackmagic
990 To enable this input device, you need the Blackmagic DeckLink SDK and you
991 need to configure with the appropriate @code{--extra-cflags}
992 and @code{--extra-ldflags}.
993 On Windows, you need to run the IDL files through @command{widl}.
995 DeckLink is very picky about the formats it supports. Pixel format is always
996 uyvy422, framerate and video size must be determined for your device with
997 @command{-list_formats 1}. Audio sample rate is always 48 kHz and the number
998 of channels currently is limited to 2 (stereo).
1005 If set to @option{true}, print a list of devices and exit.
1006 Defaults to @option{false}.
1009 If set to @option{true}, print a list of supported formats and exit.
1010 Defaults to @option{false}.
1014 @subsection Examples
1021 ffmpeg -f decklink -list_devices 1 -i dummy
1025 List supported formats:
1027 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
1031 Capture video clip at 1080i50 (format 11):
1033 ffmpeg -f decklink -i 'Intensity Pro@@11' -acodec copy -vcodec copy output.avi
1039 @c man end INPUT DEVICES