2 @c man begin INPUT DEVICES
4 Input devices are configured elements in FFmpeg which enable accessing
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}
59 Set the sample rate in Hz. Default is 48000.
62 Set the number of channels. Default is 2.
68 AVFoundation input device.
70 AVFoundation is the currently recommended framework by Apple for streamgrabbing on OSX >= 10.7 as well as on iOS.
71 The older QTKit framework has been marked deprecated since OSX version 10.7.
73 The input filename has to be given in the following syntax:
75 -i "[[VIDEO]:[AUDIO]]"
77 The first entry selects the video input while the latter selects the audio input.
78 The stream has to be specified by the device name or the device index as shown by the device list.
79 Alternatively, the video and/or audio input device can be chosen by index using the
81 -video_device_index <INDEX>
85 -audio_device_index <INDEX>
88 device name or index given in the input filename.
90 All available devices can be enumerated by using @option{-list_devices true}, listing
91 all device names and corresponding indices.
93 There are two device name aliases:
97 Select the AVFoundation default device of the corresponding type.
100 Do not record the corresponding media type.
101 This is equivalent to specifying an empty device name or index.
107 AVFoundation supports the following options:
111 @item -list_devices <TRUE|FALSE>
112 If set to true, a list of all available input devices is given showing all
113 device names and indices.
115 @item -video_device_index <INDEX>
116 Specify the video device by its index. Overrides anything given in the input filename.
118 @item -audio_device_index <INDEX>
119 Specify the audio device by its index. Overrides anything given in the input filename.
121 @item -pixel_format <FORMAT>
122 Request the video device to use a specific pixel format.
123 If the specified format is not supported, a list of available formats is given
124 and the first one in this list is used instead. Available pixel formats are:
125 @code{monob, rgb555be, rgb555le, rgb565be, rgb565le, rgb24, bgr24, 0rgb, bgr0, 0bgr, rgb0,
126 bgr48be, uyvy422, yuva444p, yuva444p16le, yuv444p, yuv422p16, yuv422p10, yuv444p10,
127 yuv420p, nv12, yuyv422, gray}
130 Set the grabbing frame rate. Default is @code{ntsc}, corresponding to a
131 frame rate of @code{30000/1001}.
134 Set the video frame size.
136 @item -capture_cursor
137 Capture the mouse pointer. Default is 0.
139 @item -capture_mouse_clicks
140 Capture the screen mouse clicks. Default is 0.
149 Print the list of AVFoundation supported devices and exit:
151 $ ffmpeg -f avfoundation -list_devices true -i ""
155 Record video from video device 0 and audio from audio device 0 into out.avi:
157 $ ffmpeg -f avfoundation -i "0:0" out.avi
161 Record video from video device 2 and audio from audio device 1 into out.avi:
163 $ ffmpeg -f avfoundation -video_device_index 2 -i ":1" out.avi
167 Record video from the system default video device using the pixel format bgr0 and do not record any audio into out.avi:
169 $ ffmpeg -f avfoundation -pixel_format bgr0 -i "default:none" out.avi
176 BSD video input device.
186 Set the video frame size. Default is @code{vga}.
190 Available values are:
210 The decklink input device provides capture capabilities for Blackmagic
213 To enable this input device, you need the Blackmagic DeckLink SDK and you
214 need to configure with the appropriate @code{--extra-cflags}
215 and @code{--extra-ldflags}.
216 On Windows, you need to run the IDL files through @command{widl}.
218 DeckLink is very picky about the formats it supports. Pixel format is
219 uyvy422 or v210, framerate and video size must be determined for your device with
220 @command{-list_formats 1}. Audio sample rate is always 48 kHz and the number
221 of channels can be 2, 8 or 16. Note that all audio channels are bundled in one single
229 If set to @option{true}, print a list of devices and exit.
230 Defaults to @option{false}.
233 If set to @option{true}, print a list of supported formats and exit.
234 Defaults to @option{false}.
236 @item format_code <FourCC>
237 This sets the input video format to the format given by the FourCC. To see
238 the supported values of your device(s) use @option{list_formats}.
239 Note that there is a FourCC @option{'pal '} that can also be used
240 as @option{pal} (3 letters).
243 If set to @samp{1}, video is captured in 10 bit v210 instead
244 of uyvy422. Not all Blackmagic devices support this option.
247 If set to nonzero, an additional teletext stream will be captured from the
248 vertical ancillary data. This option is a bitmask of the VBI lines checked,
249 specifically lines 6 to 22, and lines 318 to 335. Line 6 is the LSB in the mask.
250 Selected lines which do not contain teletext information will be ignored. You
251 can use the special @option{all} constant to select all possible lines, or
252 @option{standard} to skip lines 6, 318 and 319, which are not compatible with all
253 receivers. Capturing teletext only works for SD PAL sources in 8 bit mode.
254 To use this option, ffmpeg needs to be compiled with @code{--enable-libzvbi}.
257 Defines number of audio channels to capture. Must be @samp{2}, @samp{8} or @samp{16}.
258 Defaults to @samp{2}.
261 Sets the decklink device duplex mode. Must be @samp{unset}, @samp{half} or @samp{full}.
262 Defaults to @samp{unset}.
265 Sets the video input source. Must be @samp{unset}, @samp{sdi}, @samp{hdmi},
266 @samp{optical_sdi}, @samp{component}, @samp{composite} or @samp{s_video}.
267 Defaults to @samp{unset}.
270 Sets the audio input source. Must be @samp{unset}, @samp{embedded},
271 @samp{aes_ebu}, @samp{analog}, @samp{analog_xlr}, @samp{analog_rca} or
272 @samp{microphone}. Defaults to @samp{unset}.
275 Sets the video packet timestamp source. Must be @samp{video}, @samp{audio},
276 @samp{reference} or @samp{wallclock}. Defaults to @samp{video}.
279 Sets the audio packet timestamp source. Must be @samp{video}, @samp{audio},
280 @samp{reference} or @samp{wallclock}. Defaults to @samp{audio}.
283 If set to @samp{true}, color bars are drawn in the event of a signal loss.
284 Defaults to @samp{true}.
295 ffmpeg -f decklink -list_devices 1 -i dummy
299 List supported formats:
301 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
305 Capture video clip at 1080i50:
307 ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -acodec copy -vcodec copy output.avi
311 Capture video clip at 1080i50 10 bit:
313 ffmpeg -bm_v210 1 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -acodec copy -vcodec copy output.avi
317 Capture video clip at 1080i50 with 16 audio channels:
319 ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -acodec copy -vcodec copy output.avi
326 Windows DirectShow input device.
328 DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
329 Currently only audio and video devices are supported.
331 Multiple devices may be opened as separate inputs, but they may also be
332 opened on the same input, which should improve synchronism between them.
334 The input name should be in the format:
337 @var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
340 where @var{TYPE} can be either @var{audio} or @var{video},
341 and @var{NAME} is the device's name or alternative name..
345 If no options are specified, the device's defaults are used.
346 If the device does not support the requested options, it will
352 Set the video size in the captured video.
355 Set the frame rate in the captured video.
358 Set the sample rate (in Hz) of the captured audio.
361 Set the sample size (in bits) of the captured audio.
364 Set the number of channels in the captured audio.
367 If set to @option{true}, print a list of devices and exit.
370 If set to @option{true}, print a list of selected device's options
373 @item video_device_number
374 Set video device number for devices with the same name (starts at 0,
377 @item audio_device_number
378 Set audio device number for devices with the same name (starts at 0,
382 Select pixel format to be used by DirectShow. This may only be set when
383 the video codec is not set or set to rawvideo.
385 @item audio_buffer_size
386 Set audio device buffer size in milliseconds (which can directly
387 impact latency, depending on the device).
388 Defaults to using the audio device's
389 default buffer size (typically some multiple of 500ms).
390 Setting this value too low can degrade performance.
392 @url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
395 Select video capture pin to use by name or alternative name.
398 Select audio capture pin to use by name or alternative name.
400 @item crossbar_video_input_pin_number
401 Select video input pin number for crossbar device. This will be
402 routed to the crossbar device's Video Decoder output pin.
403 Note that changing this value can affect future invocations
404 (sets a new default) until system reboot occurs.
406 @item crossbar_audio_input_pin_number
407 Select audio input pin number for crossbar device. This will be
408 routed to the crossbar device's Audio Decoder output pin.
409 Note that changing this value can affect future invocations
410 (sets a new default) until system reboot occurs.
412 @item show_video_device_dialog
413 If set to @option{true}, before capture starts, popup a display dialog
414 to the end user, allowing them to change video filter properties
415 and configurations manually.
416 Note that for crossbar devices, adjusting values in this dialog
417 may be needed at times to toggle between PAL (25 fps) and NTSC (29.97)
418 input frame rates, sizes, interlacing, etc. Changing these values can
419 enable different scan rates/frame rates and avoiding green bars at
420 the bottom, flickering scan lines, etc.
421 Note that with some devices, changing these properties can also affect future
422 invocations (sets new defaults) until system reboot occurs.
424 @item show_audio_device_dialog
425 If set to @option{true}, before capture starts, popup a display dialog
426 to the end user, allowing them to change audio filter properties
427 and configurations manually.
429 @item show_video_crossbar_connection_dialog
430 If set to @option{true}, before capture starts, popup a display
431 dialog to the end user, allowing them to manually
432 modify crossbar pin routings, when it opens a video device.
434 @item show_audio_crossbar_connection_dialog
435 If set to @option{true}, before capture starts, popup a display
436 dialog to the end user, allowing them to manually
437 modify crossbar pin routings, when it opens an audio device.
439 @item show_analog_tv_tuner_dialog
440 If set to @option{true}, before capture starts, popup a display
441 dialog to the end user, allowing them to manually
442 modify TV channels and frequencies.
444 @item show_analog_tv_tuner_audio_dialog
445 If set to @option{true}, before capture starts, popup a display
446 dialog to the end user, allowing them to manually
447 modify TV audio (like mono vs. stereo, Language A,B or C).
449 @item audio_device_load
450 Load an audio capture filter device from file instead of searching
451 it by name. It may load additional parameters too, if the filter
452 supports the serialization of its properties to.
453 To use this an audio capture source has to be specified, but it can
454 be anything even fake one.
456 @item audio_device_save
457 Save the currently used audio capture filter device and its
458 parameters (if the filter supports it) to a file.
459 If a file with the same name exists it will be overwritten.
461 @item video_device_load
462 Load a video capture filter device from file instead of searching
463 it by name. It may load additional parameters too, if the filter
464 supports the serialization of its properties to.
465 To use this a video capture source has to be specified, but it can
466 be anything even fake one.
468 @item video_device_save
469 Save the currently used video capture filter device and its
470 parameters (if the filter supports it) to a file.
471 If a file with the same name exists it will be overwritten.
480 Print the list of DirectShow supported devices and exit:
482 $ ffmpeg -list_devices true -f dshow -i dummy
486 Open video device @var{Camera}:
488 $ ffmpeg -f dshow -i video="Camera"
492 Open second video device with name @var{Camera}:
494 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
498 Open video device @var{Camera} and audio device @var{Microphone}:
500 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
504 Print the list of supported options in selected device and exit:
506 $ ffmpeg -list_options true -f dshow -i video="Camera"
510 Specify pin names to capture by name or alternative name, specify alternative device name:
512 $ 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"
516 Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup:
518 $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
519 -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
526 Linux DV 1394 input device.
533 Set the frame rate. Default is 25.
537 Available values are:
545 Default value is @code{ntsc}.
551 Linux framebuffer input device.
553 The Linux framebuffer is a graphic hardware-independent abstraction
554 layer to show graphics on a computer monitor, typically on the
555 console. It is accessed through a file device node, usually
558 For more detailed information read the file
559 Documentation/fb/framebuffer.txt included in the Linux source tree.
561 See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
563 To record from the framebuffer device @file{/dev/fb0} with
566 ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
569 You can take a single screenshot image with the command:
571 ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
579 Set the frame rate. Default is 25.
585 Win32 GDI-based screen capture device.
587 This device allows you to capture a region of the display on Windows.
589 There are two options for the input filename:
595 title=@var{window_title}
598 The first option will capture the entire desktop, or a fixed region of the
599 desktop. The second option will instead capture the contents of a single
600 window, regardless of its position on the screen.
602 For example, to grab the entire desktop using @command{ffmpeg}:
604 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
607 Grab a 640x480 region at position @code{10,20}:
609 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
612 Grab the contents of the window named "Calculator"
614 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
621 Specify whether to draw the mouse pointer. Use the value @code{0} to
622 not draw the pointer. Default value is @code{1}.
625 Set the grabbing frame rate. Default value is @code{ntsc},
626 corresponding to a frame rate of @code{30000/1001}.
629 Show grabbed region on screen.
631 If @var{show_region} is specified with @code{1}, then the grabbing
632 region will be indicated on screen. With this option, it is easy to
633 know what is being grabbed if only a portion of the screen is grabbed.
635 Note that @var{show_region} is incompatible with grabbing the contents
640 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
644 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.
647 When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
649 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.
652 When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
654 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.
660 FireWire DV/HDV input device using libiec61883.
662 To enable this input device, you need libiec61883, libraw1394 and
663 libavc1394 installed on your system. Use the configure option
664 @code{--enable-libiec61883} to compile with the device enabled.
666 The iec61883 capture device supports capturing from a video device
667 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
668 FireWire stack (juju). This is the default DV/HDV input method in Linux
669 Kernel 2.6.37 and later, since the old FireWire stack was removed.
671 Specify the FireWire port to be used as input file, or "auto"
672 to choose the first port connected.
679 Override autodetection of DV/HDV. This should only be used if auto
680 detection does not work, or if usage of a different device type
681 should be prohibited. Treating a DV device as HDV (or vice versa) will
682 not work and result in undefined behavior.
683 The values @option{auto}, @option{dv} and @option{hdv} are supported.
686 Set maximum size of buffer for incoming data, in frames. For DV, this
687 is an exact value. For HDV, it is not frame exact, since HDV does
688 not have a fixed frame size.
691 Select the capture device by specifying its GUID. Capturing will only
692 be performed from the specified device and fails if no device with the
693 given GUID is found. This is useful to select the input if multiple
694 devices are connected at the same time.
695 Look at /sys/bus/firewire/devices to find out the GUIDs.
704 Grab and show the input of a FireWire DV/HDV device.
706 ffplay -f iec61883 -i auto
710 Grab and record the input of a FireWire DV/HDV device,
711 using a packet buffer of 100000 packets if the source is HDV.
713 ffmpeg -f iec61883 -i auto -hdvbuffer 100000 out.mpg
722 To enable this input device during configuration you need libjack
723 installed on your system.
725 A JACK input device creates one or more JACK writable clients, one for
726 each audio channel, with name @var{client_name}:input_@var{N}, where
727 @var{client_name} is the name provided by the application, and @var{N}
728 is a number which identifies the channel.
729 Each writable client will send the acquired data to the FFmpeg input
732 Once you have created one or more JACK readable clients, you need to
733 connect them to one or more JACK writable clients.
735 To connect or disconnect JACK clients you can use the @command{jack_connect}
736 and @command{jack_disconnect} programs, or do it through a graphical interface,
737 for example with @command{qjackctl}.
739 To list the JACK clients and their properties you can invoke the command
742 Follows an example which shows how to capture a JACK readable client
743 with @command{ffmpeg}.
745 # Create a JACK writable client with name "ffmpeg".
746 $ ffmpeg -f jack -i ffmpeg -y out.wav
748 # Start the sample jack_metro readable client.
749 $ jack_metro -b 120 -d 0.2 -f 4000
751 # List the current JACK clients.
760 # Connect metro to the ffmpeg writable client.
761 $ jack_connect metro:120_bpm ffmpeg:input_1
764 For more information read:
765 @url{http://jackaudio.org/}
772 Set the number of channels. Default is 2.
778 Libavfilter input virtual device.
780 This input device reads data from the open output pads of a libavfilter
783 For each filtergraph open output, the input device will create a
784 corresponding stream which is mapped to the generated output. Currently
785 only video data is supported. The filtergraph is specified through the
786 option @option{graph}.
793 Specify the filtergraph to use as input. Each video open output must be
794 labelled by a unique string of the form "out@var{N}", where @var{N} is a
795 number starting from 0 corresponding to the mapped input stream
796 generated by the device.
797 The first unlabelled output is automatically assigned to the "out0"
798 label, but all the others need to be specified explicitly.
800 The suffix "+subcc" can be appended to the output label to create an extra
801 stream with the closed captions packets attached to that output
802 (experimental; only for EIA-608 / CEA-708 for now).
803 The subcc streams are created after all the normal streams, in the order of
804 the corresponding stream.
805 For example, if there is "out19+subcc", "out7+subcc" and up to "out42", the
806 stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19.
808 If not specified defaults to the filename specified for the input
812 Set the filename of the filtergraph to be read and sent to the other
813 filters. Syntax of the filtergraph is the same as the one specified by
814 the option @var{graph}.
817 Dump graph to stderr.
825 Create a color video stream and play it back with @command{ffplay}:
827 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
831 As the previous example, but use filename for specifying the graph
832 description, and omit the "out0" label:
834 ffplay -f lavfi color=c=pink
838 Create three different video test filtered sources and play them:
840 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
844 Read an audio stream from a file using the amovie source and play it
845 back with @command{ffplay}:
847 ffplay -f lavfi "amovie=test.wav"
851 Read an audio stream and a video stream and play it back with
854 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
858 Dump decoded frames to images and closed captions to a file (experimental):
860 ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
867 Audio-CD input device based on libcdio.
869 To enable this input device during configuration you need libcdio
870 installed on your system. It requires the configure option
871 @code{--enable-libcdio}.
873 This device allows playing and grabbing from an Audio-CD.
875 For example to copy with @command{ffmpeg} the entire Audio-CD in @file{/dev/sr0},
876 you may run the command:
878 ffmpeg -f libcdio -i /dev/sr0 cd.wav
884 Set drive reading speed. Default value is 0.
886 The speed is specified CD-ROM speed units. The speed is set through
887 the libcdio @code{cdio_cddap_speed_set} function. On many CD-ROM
888 drives, specifying a value too large will result in using the fastest
892 Set paranoia recovery mode flags. It accepts one of the following values:
902 Default value is @samp{disable}.
904 For more information about the available recovery modes, consult the
905 paranoia project documentation.
910 IIDC1394 input device, based on libdc1394 and libraw1394.
912 Requires the configure option @code{--enable-libdc1394}.
916 The OpenAL input device provides audio capture on all systems with a
917 working OpenAL 1.1 implementation.
919 To enable this input device during configuration, you need OpenAL
920 headers and libraries installed on your system, and need to configure
921 FFmpeg with @code{--enable-openal}.
923 OpenAL headers and libraries should be provided as part of your OpenAL
924 implementation, or as an additional download (an SDK). Depending on your
925 installation you may need to specify additional flags via the
926 @code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
927 system to locate the OpenAL headers and libraries.
929 An incomplete list of OpenAL implementations follows:
933 The official Windows implementation, providing hardware acceleration
934 with supported devices and software fallback.
935 See @url{http://openal.org/}.
937 Portable, open source (LGPL) software implementation. Includes
938 backends for the most common sound APIs on the Windows, Linux,
939 Solaris, and BSD operating systems.
940 See @url{http://kcat.strangesoft.net/openal.html}.
942 OpenAL is part of Core Audio, the official Mac OS X Audio interface.
943 See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
946 This device allows one to capture from an audio input device handled
949 You need to specify the name of the device to capture in the provided
950 filename. If the empty string is provided, the device will
951 automatically select the default device. You can get the list of the
952 supported devices by using the option @var{list_devices}.
959 Set the number of channels in the captured audio. Only the values
960 @option{1} (monaural) and @option{2} (stereo) are currently supported.
961 Defaults to @option{2}.
964 Set the sample size (in bits) of the captured audio. Only the values
965 @option{8} and @option{16} are currently supported. Defaults to
969 Set the sample rate (in Hz) of the captured audio.
970 Defaults to @option{44.1k}.
973 If set to @option{true}, print a list of devices and exit.
974 Defaults to @option{false}.
980 Print the list of OpenAL supported devices and exit:
982 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
985 Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
987 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
990 Capture from the default device (note the empty string '' as filename):
992 $ ffmpeg -f openal -i '' out.ogg
995 Capture from two devices simultaneously, writing to two different files,
996 within the same @command{ffmpeg} command:
998 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
1000 Note: not all OpenAL implementations support multiple simultaneous capture -
1001 try the latest OpenAL Soft if the above does not work.
1005 Open Sound System input device.
1007 The filename to provide to the input device is the device node
1008 representing the OSS input device, and is usually set to
1011 For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
1014 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
1017 For more information about OSS see:
1018 @url{http://manuals.opensound.com/usersguide/dsp.html}
1025 Set the sample rate in Hz. Default is 48000.
1028 Set the number of channels. Default is 2.
1035 PulseAudio input device.
1037 To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
1039 The filename to provide to the input device is a source device or the
1042 To list the PulseAudio source devices and their properties you can invoke
1043 the command @command{pactl list sources}.
1045 More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
1050 Connect to a specific PulseAudio server, specified by an IP address.
1051 Default server is used when not provided.
1054 Specify the application name PulseAudio will use when showing active clients,
1055 by default it is the @code{LIBAVFORMAT_IDENT} string.
1058 Specify the stream name PulseAudio will use when showing active streams,
1059 by default it is "record".
1062 Specify the samplerate in Hz, by default 48kHz is used.
1065 Specify the channels in use, by default 2 (stereo) is set.
1068 Specify the number of bytes per frame, by default it is set to 1024.
1071 Specify the minimal buffering fragment in PulseAudio, it will affect the
1072 audio latency. By default it is unset.
1075 Set the initial PTS using the current time. Default is 1.
1079 @subsection Examples
1080 Record a stream from default device:
1082 ffmpeg -f pulse -i default /tmp/pulse.wav
1089 The filename passed as input is parsed to contain either a device name or index.
1090 The device index can also be given by using -video_device_index.
1091 A given device index will override any given device name.
1092 If the desired device consists of numbers only, use -video_device_index to identify it.
1093 The default device will be chosen if an empty string or the device name "default" is given.
1094 The available devices can be enumerated by using -list_devices.
1097 ffmpeg -f qtkit -i "0" out.mpg
1101 ffmpeg -f qtkit -video_device_index 0 -i "" out.mpg
1105 ffmpeg -f qtkit -i "default" out.mpg
1109 ffmpeg -f qtkit -list_devices true -i ""
1117 Set frame rate. Default is 30.
1120 If set to @code{true}, print a list of devices and exit. Default is
1123 @item video_device_index
1124 Select the video device by index for devices with the same name (starts at 0).
1132 To enable this input device during configuration you need libsndio
1133 installed on your system.
1135 The filename to provide to the input device is the device node
1136 representing the sndio input device, and is usually set to
1139 For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
1142 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
1150 Set the sample rate in Hz. Default is 48000.
1153 Set the number of channels. Default is 2.
1157 @section video4linux2, v4l2
1159 Video4Linux2 input video device.
1161 "v4l2" can be used as alias for "video4linux2".
1163 If FFmpeg is built with v4l-utils support (by using the
1164 @code{--enable-libv4l2} configure option), it is possible to use it with the
1165 @code{-use_libv4l2} input device option.
1167 The name of the device to grab is a file device node, usually Linux
1168 systems tend to automatically create such nodes when the device
1169 (e.g. an USB webcam) is plugged into the system, and has a name of the
1170 kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
1173 Video4Linux2 devices usually support a limited set of
1174 @var{width}x@var{height} sizes and frame rates. You can check which are
1175 supported using @command{-list_formats all} for Video4Linux2 devices.
1176 Some devices, like TV cards, support one or more standards. It is possible
1177 to list all the supported standards using @command{-list_standards all}.
1179 The time base for the timestamps is 1 microsecond. Depending on the kernel
1180 version and configuration, the timestamps may be derived from the real time
1181 clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
1182 boot time, unaffected by NTP or manual changes to the clock). The
1183 @option{-timestamps abs} or @option{-ts abs} option can be used to force
1184 conversion into the real time clock.
1186 Some usage examples of the video4linux2 device with @command{ffmpeg}
1187 and @command{ffplay}:
1190 List supported formats for a video4linux2 device:
1192 ffplay -f video4linux2 -list_formats all /dev/video0
1196 Grab and show the input of a video4linux2 device:
1198 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
1202 Grab and record the input of a video4linux2 device, leave the
1203 frame rate and size as previously set:
1205 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
1209 For more information about Video4Linux, check @url{http://linuxtv.org/}.
1215 Set the standard. Must be the name of a supported standard. To get a
1216 list of the supported standards, use the @option{list_standards}
1220 Set the input channel number. Default to -1, which means using the
1221 previously selected channel.
1224 Set the video frame size. The argument must be a string in the form
1225 @var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
1228 Select the pixel format (only valid for raw video input).
1231 Set the preferred pixel format (for raw video) or a codec name.
1232 This option allows one to select the input format, when several are
1236 Set the preferred video frame rate.
1239 List available formats (supported pixel formats, codecs, and frame
1242 Available values are:
1245 Show all available (compressed and non-compressed) formats.
1248 Show only raw video (non-compressed) formats.
1251 Show only compressed formats.
1254 @item list_standards
1255 List supported standards and exit.
1257 Available values are:
1260 Show all supported standards.
1263 @item timestamps, ts
1264 Set type of timestamps for grabbed frames.
1266 Available values are:
1269 Use timestamps from the kernel.
1272 Use absolute timestamps (wall clock).
1275 Force conversion from monotonic to absolute timestamps.
1278 Default value is @code{default}.
1281 Use libv4l2 (v4l-utils) conversion functions. Default is 0.
1287 VfW (Video for Windows) capture input device.
1289 The filename passed as input is the capture driver number, ranging from
1290 0 to 9. You may use "list" as filename to print a list of drivers. Any
1291 other filename will be interpreted as device number 0.
1298 Set the video frame size.
1301 Set the grabbing frame rate. Default value is @code{ntsc},
1302 corresponding to a frame rate of @code{30000/1001}.
1308 X11 video input device.
1310 To enable this input device during configuration you need libxcb
1311 installed on your system. It will be automatically detected during
1314 This device allows one to capture a region of an X11 display.
1316 The filename passed as input has the syntax:
1318 [@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
1321 @var{hostname}:@var{display_number}.@var{screen_number} specifies the
1322 X11 display name of the screen to grab from. @var{hostname} can be
1323 omitted, and defaults to "localhost". The environment variable
1324 @env{DISPLAY} contains the default display name.
1326 @var{x_offset} and @var{y_offset} specify the offsets of the grabbed
1327 area with respect to the top-left border of the X11 screen. They
1330 Check the X11 documentation (e.g. @command{man X}) for more detailed
1333 Use the @command{xdpyinfo} program for getting basic information about
1334 the properties of your X11 display (e.g. grep for "name" or
1337 For example to grab from @file{:0.0} using @command{ffmpeg}:
1339 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
1342 Grab at position @code{10,20}:
1344 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1351 Specify whether to draw the mouse pointer. A value of @code{0} specifies
1352 not to draw the pointer. Default value is @code{1}.
1355 Make the grabbed area follow the mouse. The argument can be
1356 @code{centered} or a number of pixels @var{PIXELS}.
1358 When it is specified with "centered", the grabbing region follows the mouse
1359 pointer and keeps the pointer at the center of region; otherwise, the region
1360 follows only when the mouse pointer reaches within @var{PIXELS} (greater than
1361 zero) to the edge of region.
1365 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
1368 To follow only when the mouse pointer reaches within 100 pixels to edge:
1370 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
1374 Set the grabbing frame rate. Default value is @code{ntsc},
1375 corresponding to a frame rate of @code{30000/1001}.
1378 Show grabbed region on screen.
1380 If @var{show_region} is specified with @code{1}, then the grabbing
1381 region will be indicated on screen. With this option, it is easy to
1382 know what is being grabbed if only a portion of the screen is grabbed.
1385 Set the region border thickness if @option{-show_region 1} is used.
1386 Range is 1 to 128 and default is 3 (XCB-based x11grab only).
1390 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1393 With @var{follow_mouse}:
1395 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
1399 Set the video frame size. Default value is @code{vga}.
1403 Set the grabbing region coordinates. They are expressed as offset from
1404 the top left corner of the X11 window and correspond to the
1405 @var{x_offset} and @var{y_offset} parameters in the device name. The
1406 default value for both options is 0.
1409 @c man end INPUT DEVICES