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. Both SD PAL (576i) and HD (1080i or 1080p)
249 sources are supported. In case of HD sources, OP47 packets are decoded.
251 This option is a bitmask of the SD PAL VBI lines captured, specifically lines 6
252 to 22, and lines 318 to 335. Line 6 is the LSB in the mask. Selected lines
253 which do not contain teletext information will be ignored. You can use the
254 special @option{all} constant to select all possible lines, or
255 @option{standard} to skip lines 6, 318 and 319, which are not compatible with
258 For SD sources, ffmpeg needs to be compiled with @code{--enable-libzvbi}. For
259 HD sources, on older (pre-4K) DeckLink card models you have to capture in 10
263 Defines number of audio channels to capture. Must be @samp{2}, @samp{8} or @samp{16}.
264 Defaults to @samp{2}.
267 Sets the decklink device duplex mode. Must be @samp{unset}, @samp{half} or @samp{full}.
268 Defaults to @samp{unset}.
271 Sets the video input source. Must be @samp{unset}, @samp{sdi}, @samp{hdmi},
272 @samp{optical_sdi}, @samp{component}, @samp{composite} or @samp{s_video}.
273 Defaults to @samp{unset}.
276 Sets the audio input source. Must be @samp{unset}, @samp{embedded},
277 @samp{aes_ebu}, @samp{analog}, @samp{analog_xlr}, @samp{analog_rca} or
278 @samp{microphone}. Defaults to @samp{unset}.
281 Sets the video packet timestamp source. Must be @samp{video}, @samp{audio},
282 @samp{reference} or @samp{wallclock}. Defaults to @samp{video}.
285 Sets the audio packet timestamp source. Must be @samp{video}, @samp{audio},
286 @samp{reference} or @samp{wallclock}. Defaults to @samp{audio}.
289 If set to @samp{true}, color bars are drawn in the event of a signal loss.
290 Defaults to @samp{true}.
301 ffmpeg -f decklink -list_devices 1 -i dummy
305 List supported formats:
307 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
311 Capture video clip at 1080i50:
313 ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -acodec copy -vcodec copy output.avi
317 Capture video clip at 1080i50 10 bit:
319 ffmpeg -bm_v210 1 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -acodec copy -vcodec copy output.avi
323 Capture video clip at 1080i50 with 16 audio channels:
325 ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -acodec copy -vcodec copy output.avi
332 Windows DirectShow input device.
334 DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
335 Currently only audio and video devices are supported.
337 Multiple devices may be opened as separate inputs, but they may also be
338 opened on the same input, which should improve synchronism between them.
340 The input name should be in the format:
343 @var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
346 where @var{TYPE} can be either @var{audio} or @var{video},
347 and @var{NAME} is the device's name or alternative name..
351 If no options are specified, the device's defaults are used.
352 If the device does not support the requested options, it will
358 Set the video size in the captured video.
361 Set the frame rate in the captured video.
364 Set the sample rate (in Hz) of the captured audio.
367 Set the sample size (in bits) of the captured audio.
370 Set the number of channels in the captured audio.
373 If set to @option{true}, print a list of devices and exit.
376 If set to @option{true}, print a list of selected device's options
379 @item video_device_number
380 Set video device number for devices with the same name (starts at 0,
383 @item audio_device_number
384 Set audio device number for devices with the same name (starts at 0,
388 Select pixel format to be used by DirectShow. This may only be set when
389 the video codec is not set or set to rawvideo.
391 @item audio_buffer_size
392 Set audio device buffer size in milliseconds (which can directly
393 impact latency, depending on the device).
394 Defaults to using the audio device's
395 default buffer size (typically some multiple of 500ms).
396 Setting this value too low can degrade performance.
398 @url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
401 Select video capture pin to use by name or alternative name.
404 Select audio capture pin to use by name or alternative name.
406 @item crossbar_video_input_pin_number
407 Select video input pin number for crossbar device. This will be
408 routed to the crossbar device's Video Decoder output pin.
409 Note that changing this value can affect future invocations
410 (sets a new default) until system reboot occurs.
412 @item crossbar_audio_input_pin_number
413 Select audio input pin number for crossbar device. This will be
414 routed to the crossbar device's Audio Decoder output pin.
415 Note that changing this value can affect future invocations
416 (sets a new default) until system reboot occurs.
418 @item show_video_device_dialog
419 If set to @option{true}, before capture starts, popup a display dialog
420 to the end user, allowing them to change video filter properties
421 and configurations manually.
422 Note that for crossbar devices, adjusting values in this dialog
423 may be needed at times to toggle between PAL (25 fps) and NTSC (29.97)
424 input frame rates, sizes, interlacing, etc. Changing these values can
425 enable different scan rates/frame rates and avoiding green bars at
426 the bottom, flickering scan lines, etc.
427 Note that with some devices, changing these properties can also affect future
428 invocations (sets new defaults) until system reboot occurs.
430 @item show_audio_device_dialog
431 If set to @option{true}, before capture starts, popup a display dialog
432 to the end user, allowing them to change audio filter properties
433 and configurations manually.
435 @item show_video_crossbar_connection_dialog
436 If set to @option{true}, before capture starts, popup a display
437 dialog to the end user, allowing them to manually
438 modify crossbar pin routings, when it opens a video device.
440 @item show_audio_crossbar_connection_dialog
441 If set to @option{true}, before capture starts, popup a display
442 dialog to the end user, allowing them to manually
443 modify crossbar pin routings, when it opens an audio device.
445 @item show_analog_tv_tuner_dialog
446 If set to @option{true}, before capture starts, popup a display
447 dialog to the end user, allowing them to manually
448 modify TV channels and frequencies.
450 @item show_analog_tv_tuner_audio_dialog
451 If set to @option{true}, before capture starts, popup a display
452 dialog to the end user, allowing them to manually
453 modify TV audio (like mono vs. stereo, Language A,B or C).
455 @item audio_device_load
456 Load an audio capture filter device from file instead of searching
457 it by name. It may load additional parameters too, if the filter
458 supports the serialization of its properties to.
459 To use this an audio capture source has to be specified, but it can
460 be anything even fake one.
462 @item audio_device_save
463 Save the currently used audio capture filter device and its
464 parameters (if the filter supports it) to a file.
465 If a file with the same name exists it will be overwritten.
467 @item video_device_load
468 Load a video capture filter device from file instead of searching
469 it by name. It may load additional parameters too, if the filter
470 supports the serialization of its properties to.
471 To use this a video capture source has to be specified, but it can
472 be anything even fake one.
474 @item video_device_save
475 Save the currently used video capture filter device and its
476 parameters (if the filter supports it) to a file.
477 If a file with the same name exists it will be overwritten.
486 Print the list of DirectShow supported devices and exit:
488 $ ffmpeg -list_devices true -f dshow -i dummy
492 Open video device @var{Camera}:
494 $ ffmpeg -f dshow -i video="Camera"
498 Open second video device with name @var{Camera}:
500 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
504 Open video device @var{Camera} and audio device @var{Microphone}:
506 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
510 Print the list of supported options in selected device and exit:
512 $ ffmpeg -list_options true -f dshow -i video="Camera"
516 Specify pin names to capture by name or alternative name, specify alternative device name:
518 $ 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"
522 Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup:
524 $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
525 -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
532 Linux DV 1394 input device.
539 Set the frame rate. Default is 25.
543 Available values are:
551 Default value is @code{ntsc}.
557 Linux framebuffer input device.
559 The Linux framebuffer is a graphic hardware-independent abstraction
560 layer to show graphics on a computer monitor, typically on the
561 console. It is accessed through a file device node, usually
564 For more detailed information read the file
565 Documentation/fb/framebuffer.txt included in the Linux source tree.
567 See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
569 To record from the framebuffer device @file{/dev/fb0} with
572 ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
575 You can take a single screenshot image with the command:
577 ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
585 Set the frame rate. Default is 25.
591 Win32 GDI-based screen capture device.
593 This device allows you to capture a region of the display on Windows.
595 There are two options for the input filename:
601 title=@var{window_title}
604 The first option will capture the entire desktop, or a fixed region of the
605 desktop. The second option will instead capture the contents of a single
606 window, regardless of its position on the screen.
608 For example, to grab the entire desktop using @command{ffmpeg}:
610 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
613 Grab a 640x480 region at position @code{10,20}:
615 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
618 Grab the contents of the window named "Calculator"
620 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
627 Specify whether to draw the mouse pointer. Use the value @code{0} to
628 not draw the pointer. Default value is @code{1}.
631 Set the grabbing frame rate. Default value is @code{ntsc},
632 corresponding to a frame rate of @code{30000/1001}.
635 Show grabbed region on screen.
637 If @var{show_region} is specified with @code{1}, then the grabbing
638 region will be indicated on screen. With this option, it is easy to
639 know what is being grabbed if only a portion of the screen is grabbed.
641 Note that @var{show_region} is incompatible with grabbing the contents
646 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
650 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.
653 When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
655 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.
658 When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
660 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.
666 FireWire DV/HDV input device using libiec61883.
668 To enable this input device, you need libiec61883, libraw1394 and
669 libavc1394 installed on your system. Use the configure option
670 @code{--enable-libiec61883} to compile with the device enabled.
672 The iec61883 capture device supports capturing from a video device
673 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
674 FireWire stack (juju). This is the default DV/HDV input method in Linux
675 Kernel 2.6.37 and later, since the old FireWire stack was removed.
677 Specify the FireWire port to be used as input file, or "auto"
678 to choose the first port connected.
685 Override autodetection of DV/HDV. This should only be used if auto
686 detection does not work, or if usage of a different device type
687 should be prohibited. Treating a DV device as HDV (or vice versa) will
688 not work and result in undefined behavior.
689 The values @option{auto}, @option{dv} and @option{hdv} are supported.
692 Set maximum size of buffer for incoming data, in frames. For DV, this
693 is an exact value. For HDV, it is not frame exact, since HDV does
694 not have a fixed frame size.
697 Select the capture device by specifying its GUID. Capturing will only
698 be performed from the specified device and fails if no device with the
699 given GUID is found. This is useful to select the input if multiple
700 devices are connected at the same time.
701 Look at /sys/bus/firewire/devices to find out the GUIDs.
710 Grab and show the input of a FireWire DV/HDV device.
712 ffplay -f iec61883 -i auto
716 Grab and record the input of a FireWire DV/HDV device,
717 using a packet buffer of 100000 packets if the source is HDV.
719 ffmpeg -f iec61883 -i auto -hdvbuffer 100000 out.mpg
728 To enable this input device during configuration you need libjack
729 installed on your system.
731 A JACK input device creates one or more JACK writable clients, one for
732 each audio channel, with name @var{client_name}:input_@var{N}, where
733 @var{client_name} is the name provided by the application, and @var{N}
734 is a number which identifies the channel.
735 Each writable client will send the acquired data to the FFmpeg input
738 Once you have created one or more JACK readable clients, you need to
739 connect them to one or more JACK writable clients.
741 To connect or disconnect JACK clients you can use the @command{jack_connect}
742 and @command{jack_disconnect} programs, or do it through a graphical interface,
743 for example with @command{qjackctl}.
745 To list the JACK clients and their properties you can invoke the command
748 Follows an example which shows how to capture a JACK readable client
749 with @command{ffmpeg}.
751 # Create a JACK writable client with name "ffmpeg".
752 $ ffmpeg -f jack -i ffmpeg -y out.wav
754 # Start the sample jack_metro readable client.
755 $ jack_metro -b 120 -d 0.2 -f 4000
757 # List the current JACK clients.
766 # Connect metro to the ffmpeg writable client.
767 $ jack_connect metro:120_bpm ffmpeg:input_1
770 For more information read:
771 @url{http://jackaudio.org/}
778 Set the number of channels. Default is 2.
784 Libavfilter input virtual device.
786 This input device reads data from the open output pads of a libavfilter
789 For each filtergraph open output, the input device will create a
790 corresponding stream which is mapped to the generated output. Currently
791 only video data is supported. The filtergraph is specified through the
792 option @option{graph}.
799 Specify the filtergraph to use as input. Each video open output must be
800 labelled by a unique string of the form "out@var{N}", where @var{N} is a
801 number starting from 0 corresponding to the mapped input stream
802 generated by the device.
803 The first unlabelled output is automatically assigned to the "out0"
804 label, but all the others need to be specified explicitly.
806 The suffix "+subcc" can be appended to the output label to create an extra
807 stream with the closed captions packets attached to that output
808 (experimental; only for EIA-608 / CEA-708 for now).
809 The subcc streams are created after all the normal streams, in the order of
810 the corresponding stream.
811 For example, if there is "out19+subcc", "out7+subcc" and up to "out42", the
812 stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19.
814 If not specified defaults to the filename specified for the input
818 Set the filename of the filtergraph to be read and sent to the other
819 filters. Syntax of the filtergraph is the same as the one specified by
820 the option @var{graph}.
823 Dump graph to stderr.
831 Create a color video stream and play it back with @command{ffplay}:
833 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
837 As the previous example, but use filename for specifying the graph
838 description, and omit the "out0" label:
840 ffplay -f lavfi color=c=pink
844 Create three different video test filtered sources and play them:
846 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
850 Read an audio stream from a file using the amovie source and play it
851 back with @command{ffplay}:
853 ffplay -f lavfi "amovie=test.wav"
857 Read an audio stream and a video stream and play it back with
860 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
864 Dump decoded frames to images and closed captions to a file (experimental):
866 ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
873 Audio-CD input device based on libcdio.
875 To enable this input device during configuration you need libcdio
876 installed on your system. It requires the configure option
877 @code{--enable-libcdio}.
879 This device allows playing and grabbing from an Audio-CD.
881 For example to copy with @command{ffmpeg} the entire Audio-CD in @file{/dev/sr0},
882 you may run the command:
884 ffmpeg -f libcdio -i /dev/sr0 cd.wav
890 Set drive reading speed. Default value is 0.
892 The speed is specified CD-ROM speed units. The speed is set through
893 the libcdio @code{cdio_cddap_speed_set} function. On many CD-ROM
894 drives, specifying a value too large will result in using the fastest
898 Set paranoia recovery mode flags. It accepts one of the following values:
908 Default value is @samp{disable}.
910 For more information about the available recovery modes, consult the
911 paranoia project documentation.
916 IIDC1394 input device, based on libdc1394 and libraw1394.
918 Requires the configure option @code{--enable-libdc1394}.
922 The OpenAL input device provides audio capture on all systems with a
923 working OpenAL 1.1 implementation.
925 To enable this input device during configuration, you need OpenAL
926 headers and libraries installed on your system, and need to configure
927 FFmpeg with @code{--enable-openal}.
929 OpenAL headers and libraries should be provided as part of your OpenAL
930 implementation, or as an additional download (an SDK). Depending on your
931 installation you may need to specify additional flags via the
932 @code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
933 system to locate the OpenAL headers and libraries.
935 An incomplete list of OpenAL implementations follows:
939 The official Windows implementation, providing hardware acceleration
940 with supported devices and software fallback.
941 See @url{http://openal.org/}.
943 Portable, open source (LGPL) software implementation. Includes
944 backends for the most common sound APIs on the Windows, Linux,
945 Solaris, and BSD operating systems.
946 See @url{http://kcat.strangesoft.net/openal.html}.
948 OpenAL is part of Core Audio, the official Mac OS X Audio interface.
949 See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
952 This device allows one to capture from an audio input device handled
955 You need to specify the name of the device to capture in the provided
956 filename. If the empty string is provided, the device will
957 automatically select the default device. You can get the list of the
958 supported devices by using the option @var{list_devices}.
965 Set the number of channels in the captured audio. Only the values
966 @option{1} (monaural) and @option{2} (stereo) are currently supported.
967 Defaults to @option{2}.
970 Set the sample size (in bits) of the captured audio. Only the values
971 @option{8} and @option{16} are currently supported. Defaults to
975 Set the sample rate (in Hz) of the captured audio.
976 Defaults to @option{44.1k}.
979 If set to @option{true}, print a list of devices and exit.
980 Defaults to @option{false}.
986 Print the list of OpenAL supported devices and exit:
988 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
991 Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
993 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
996 Capture from the default device (note the empty string '' as filename):
998 $ ffmpeg -f openal -i '' out.ogg
1001 Capture from two devices simultaneously, writing to two different files,
1002 within the same @command{ffmpeg} command:
1004 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
1006 Note: not all OpenAL implementations support multiple simultaneous capture -
1007 try the latest OpenAL Soft if the above does not work.
1011 Open Sound System input device.
1013 The filename to provide to the input device is the device node
1014 representing the OSS input device, and is usually set to
1017 For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
1020 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
1023 For more information about OSS see:
1024 @url{http://manuals.opensound.com/usersguide/dsp.html}
1031 Set the sample rate in Hz. Default is 48000.
1034 Set the number of channels. Default is 2.
1041 PulseAudio input device.
1043 To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
1045 The filename to provide to the input device is a source device or the
1048 To list the PulseAudio source devices and their properties you can invoke
1049 the command @command{pactl list sources}.
1051 More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
1056 Connect to a specific PulseAudio server, specified by an IP address.
1057 Default server is used when not provided.
1060 Specify the application name PulseAudio will use when showing active clients,
1061 by default it is the @code{LIBAVFORMAT_IDENT} string.
1064 Specify the stream name PulseAudio will use when showing active streams,
1065 by default it is "record".
1068 Specify the samplerate in Hz, by default 48kHz is used.
1071 Specify the channels in use, by default 2 (stereo) is set.
1074 Specify the number of bytes per frame, by default it is set to 1024.
1077 Specify the minimal buffering fragment in PulseAudio, it will affect the
1078 audio latency. By default it is unset.
1081 Set the initial PTS using the current time. Default is 1.
1085 @subsection Examples
1086 Record a stream from default device:
1088 ffmpeg -f pulse -i default /tmp/pulse.wav
1095 The filename passed as input is parsed to contain either a device name or index.
1096 The device index can also be given by using -video_device_index.
1097 A given device index will override any given device name.
1098 If the desired device consists of numbers only, use -video_device_index to identify it.
1099 The default device will be chosen if an empty string or the device name "default" is given.
1100 The available devices can be enumerated by using -list_devices.
1103 ffmpeg -f qtkit -i "0" out.mpg
1107 ffmpeg -f qtkit -video_device_index 0 -i "" out.mpg
1111 ffmpeg -f qtkit -i "default" out.mpg
1115 ffmpeg -f qtkit -list_devices true -i ""
1123 Set frame rate. Default is 30.
1126 If set to @code{true}, print a list of devices and exit. Default is
1129 @item video_device_index
1130 Select the video device by index for devices with the same name (starts at 0).
1138 To enable this input device during configuration you need libsndio
1139 installed on your system.
1141 The filename to provide to the input device is the device node
1142 representing the sndio input device, and is usually set to
1145 For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
1148 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
1156 Set the sample rate in Hz. Default is 48000.
1159 Set the number of channels. Default is 2.
1163 @section video4linux2, v4l2
1165 Video4Linux2 input video device.
1167 "v4l2" can be used as alias for "video4linux2".
1169 If FFmpeg is built with v4l-utils support (by using the
1170 @code{--enable-libv4l2} configure option), it is possible to use it with the
1171 @code{-use_libv4l2} input device option.
1173 The name of the device to grab is a file device node, usually Linux
1174 systems tend to automatically create such nodes when the device
1175 (e.g. an USB webcam) is plugged into the system, and has a name of the
1176 kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
1179 Video4Linux2 devices usually support a limited set of
1180 @var{width}x@var{height} sizes and frame rates. You can check which are
1181 supported using @command{-list_formats all} for Video4Linux2 devices.
1182 Some devices, like TV cards, support one or more standards. It is possible
1183 to list all the supported standards using @command{-list_standards all}.
1185 The time base for the timestamps is 1 microsecond. Depending on the kernel
1186 version and configuration, the timestamps may be derived from the real time
1187 clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
1188 boot time, unaffected by NTP or manual changes to the clock). The
1189 @option{-timestamps abs} or @option{-ts abs} option can be used to force
1190 conversion into the real time clock.
1192 Some usage examples of the video4linux2 device with @command{ffmpeg}
1193 and @command{ffplay}:
1196 List supported formats for a video4linux2 device:
1198 ffplay -f video4linux2 -list_formats all /dev/video0
1202 Grab and show the input of a video4linux2 device:
1204 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
1208 Grab and record the input of a video4linux2 device, leave the
1209 frame rate and size as previously set:
1211 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
1215 For more information about Video4Linux, check @url{http://linuxtv.org/}.
1221 Set the standard. Must be the name of a supported standard. To get a
1222 list of the supported standards, use the @option{list_standards}
1226 Set the input channel number. Default to -1, which means using the
1227 previously selected channel.
1230 Set the video frame size. The argument must be a string in the form
1231 @var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
1234 Select the pixel format (only valid for raw video input).
1237 Set the preferred pixel format (for raw video) or a codec name.
1238 This option allows one to select the input format, when several are
1242 Set the preferred video frame rate.
1245 List available formats (supported pixel formats, codecs, and frame
1248 Available values are:
1251 Show all available (compressed and non-compressed) formats.
1254 Show only raw video (non-compressed) formats.
1257 Show only compressed formats.
1260 @item list_standards
1261 List supported standards and exit.
1263 Available values are:
1266 Show all supported standards.
1269 @item timestamps, ts
1270 Set type of timestamps for grabbed frames.
1272 Available values are:
1275 Use timestamps from the kernel.
1278 Use absolute timestamps (wall clock).
1281 Force conversion from monotonic to absolute timestamps.
1284 Default value is @code{default}.
1287 Use libv4l2 (v4l-utils) conversion functions. Default is 0.
1293 VfW (Video for Windows) capture input device.
1295 The filename passed as input is the capture driver number, ranging from
1296 0 to 9. You may use "list" as filename to print a list of drivers. Any
1297 other filename will be interpreted as device number 0.
1304 Set the video frame size.
1307 Set the grabbing frame rate. Default value is @code{ntsc},
1308 corresponding to a frame rate of @code{30000/1001}.
1314 X11 video input device.
1316 To enable this input device during configuration you need libxcb
1317 installed on your system. It will be automatically detected during
1320 This device allows one to capture a region of an X11 display.
1322 The filename passed as input has the syntax:
1324 [@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
1327 @var{hostname}:@var{display_number}.@var{screen_number} specifies the
1328 X11 display name of the screen to grab from. @var{hostname} can be
1329 omitted, and defaults to "localhost". The environment variable
1330 @env{DISPLAY} contains the default display name.
1332 @var{x_offset} and @var{y_offset} specify the offsets of the grabbed
1333 area with respect to the top-left border of the X11 screen. They
1336 Check the X11 documentation (e.g. @command{man X}) for more detailed
1339 Use the @command{xdpyinfo} program for getting basic information about
1340 the properties of your X11 display (e.g. grep for "name" or
1343 For example to grab from @file{:0.0} using @command{ffmpeg}:
1345 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
1348 Grab at position @code{10,20}:
1350 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1357 Specify whether to draw the mouse pointer. A value of @code{0} specifies
1358 not to draw the pointer. Default value is @code{1}.
1361 Make the grabbed area follow the mouse. The argument can be
1362 @code{centered} or a number of pixels @var{PIXELS}.
1364 When it is specified with "centered", the grabbing region follows the mouse
1365 pointer and keeps the pointer at the center of region; otherwise, the region
1366 follows only when the mouse pointer reaches within @var{PIXELS} (greater than
1367 zero) to the edge of region.
1371 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
1374 To follow only when the mouse pointer reaches within 100 pixels to edge:
1376 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
1380 Set the grabbing frame rate. Default value is @code{ntsc},
1381 corresponding to a frame rate of @code{30000/1001}.
1384 Show grabbed region on screen.
1386 If @var{show_region} is specified with @code{1}, then the grabbing
1387 region will be indicated on screen. With this option, it is easy to
1388 know what is being grabbed if only a portion of the screen is grabbed.
1391 Set the region border thickness if @option{-show_region 1} is used.
1392 Range is 1 to 128 and default is 3 (XCB-based x11grab only).
1396 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1399 With @var{follow_mouse}:
1401 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
1405 Set the video frame size. Default value is @code{vga}.
1409 Set the grabbing region coordinates. They are expressed as offset from
1410 the top left corner of the X11 window and correspond to the
1411 @var{x_offset} and @var{y_offset} parameters in the device name. The
1412 default value for both options is 0.
1415 @c man end INPUT DEVICES