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.
66 @section android_camera
68 Android camera input device.
70 This input devices uses the Android Camera2 NDK API which is
71 available on devices with API level 24+. The availability of
72 android_camera is autodetected during configuration.
74 This device allows capturing from all cameras on an Android device,
75 which are integrated into the Camera2 NDK API.
77 The available cameras are enumerated internally and can be selected
78 with the @var{camera_index} parameter. The input file string is
81 Generally the back facing camera has index 0 while the front facing
89 Set the video size given as a string such as 640x480 or hd720.
90 Falls back to the first available configuration reported by
91 Android if requested video size is not available or by default.
94 Set the video framerate.
95 Falls back to the first available configuration reported by
96 Android if requested framerate is not available or by default (-1).
99 Set the index of the camera to use. Default is 0.
101 @item input_queue_size
102 Set the maximum number of frames to buffer. Default is 5.
106 @section avfoundation
108 AVFoundation input device.
110 AVFoundation is the currently recommended framework by Apple for streamgrabbing on OSX >= 10.7 as well as on iOS.
112 The input filename has to be given in the following syntax:
114 -i "[[VIDEO]:[AUDIO]]"
116 The first entry selects the video input while the latter selects the audio input.
117 The stream has to be specified by the device name or the device index as shown by the device list.
118 Alternatively, the video and/or audio input device can be chosen by index using the
120 -video_device_index <INDEX>
124 -audio_device_index <INDEX>
127 device name or index given in the input filename.
129 All available devices can be enumerated by using @option{-list_devices true}, listing
130 all device names and corresponding indices.
132 There are two device name aliases:
136 Select the AVFoundation default device of the corresponding type.
139 Do not record the corresponding media type.
140 This is equivalent to specifying an empty device name or index.
146 AVFoundation supports the following options:
150 @item -list_devices <TRUE|FALSE>
151 If set to true, a list of all available input devices is given showing all
152 device names and indices.
154 @item -video_device_index <INDEX>
155 Specify the video device by its index. Overrides anything given in the input filename.
157 @item -audio_device_index <INDEX>
158 Specify the audio device by its index. Overrides anything given in the input filename.
160 @item -pixel_format <FORMAT>
161 Request the video device to use a specific pixel format.
162 If the specified format is not supported, a list of available formats is given
163 and the first one in this list is used instead. Available pixel formats are:
164 @code{monob, rgb555be, rgb555le, rgb565be, rgb565le, rgb24, bgr24, 0rgb, bgr0, 0bgr, rgb0,
165 bgr48be, uyvy422, yuva444p, yuva444p16le, yuv444p, yuv422p16, yuv422p10, yuv444p10,
166 yuv420p, nv12, yuyv422, gray}
169 Set the grabbing frame rate. Default is @code{ntsc}, corresponding to a
170 frame rate of @code{30000/1001}.
173 Set the video frame size.
175 @item -capture_cursor
176 Capture the mouse pointer. Default is 0.
178 @item -capture_mouse_clicks
179 Capture the screen mouse clicks. Default is 0.
181 @item -capture_raw_data
182 Capture the raw device data. Default is 0.
183 Using this option may result in receiving the underlying data delivered to the AVFoundation framework. E.g. for muxed devices that sends raw DV data to the framework (like tape-based camcorders), setting this option to false results in extracted video frames captured in the designated pixel format only. Setting this option to true results in receiving the raw DV stream untouched.
191 Print the list of AVFoundation supported devices and exit:
193 $ ffmpeg -f avfoundation -list_devices true -i ""
197 Record video from video device 0 and audio from audio device 0 into out.avi:
199 $ ffmpeg -f avfoundation -i "0:0" out.avi
203 Record video from video device 2 and audio from audio device 1 into out.avi:
205 $ ffmpeg -f avfoundation -video_device_index 2 -i ":1" out.avi
209 Record video from the system default video device using the pixel format bgr0 and do not record any audio into out.avi:
211 $ ffmpeg -f avfoundation -pixel_format bgr0 -i "default:none" out.avi
215 Record raw DV data from a suitable input device and write the output into out.dv:
217 $ ffmpeg -f avfoundation -capture_raw_data true -i "zr100:none" out.dv
225 BSD video input device.
235 Set the video frame size. Default is @code{vga}.
239 Available values are:
259 The decklink input device provides capture capabilities for Blackmagic
262 To enable this input device, you need the Blackmagic DeckLink SDK and you
263 need to configure with the appropriate @code{--extra-cflags}
264 and @code{--extra-ldflags}.
265 On Windows, you need to run the IDL files through @command{widl}.
267 DeckLink is very picky about the formats it supports. Pixel format of the
268 input can be set with @option{raw_format}.
269 Framerate and video size must be determined for your device with
270 @command{-list_formats 1}. Audio sample rate is always 48 kHz and the number
271 of channels can be 2, 8 or 16. Note that all audio channels are bundled in one single
279 If set to @option{true}, print a list of devices and exit.
280 Defaults to @option{false}. This option is deprecated, please use the
281 @code{-sources} option of ffmpeg to list the available input devices.
284 If set to @option{true}, print a list of supported formats and exit.
285 Defaults to @option{false}.
287 @item format_code <FourCC>
288 This sets the input video format to the format given by the FourCC. To see
289 the supported values of your device(s) use @option{list_formats}.
290 Note that there is a FourCC @option{'pal '} that can also be used
291 as @option{pal} (3 letters).
292 Default behavior is autodetection of the input video format, if the hardware
296 Set the pixel format of the captured video.
297 Available values are:
312 If set to nonzero, an additional teletext stream will be captured from the
313 vertical ancillary data. Both SD PAL (576i) and HD (1080i or 1080p)
314 sources are supported. In case of HD sources, OP47 packets are decoded.
316 This option is a bitmask of the SD PAL VBI lines captured, specifically lines 6
317 to 22, and lines 318 to 335. Line 6 is the LSB in the mask. Selected lines
318 which do not contain teletext information will be ignored. You can use the
319 special @option{all} constant to select all possible lines, or
320 @option{standard} to skip lines 6, 318 and 319, which are not compatible with
323 For SD sources, ffmpeg needs to be compiled with @code{--enable-libzvbi}. For
324 HD sources, on older (pre-4K) DeckLink card models you have to capture in 10
328 Defines number of audio channels to capture. Must be @samp{2}, @samp{8} or @samp{16}.
329 Defaults to @samp{2}.
332 Sets the decklink device duplex mode. Must be @samp{unset}, @samp{half} or @samp{full}.
333 Defaults to @samp{unset}.
335 @item timecode_format
336 Timecode type to include in the frame and video stream metadata. Must be
337 @samp{none}, @samp{rp188vitc}, @samp{rp188vitc2}, @samp{rp188ltc},
338 @samp{rp188any}, @samp{vitc}, @samp{vitc2}, or @samp{serial}. Defaults to
339 @samp{none} (not included).
342 Sets the video input source. Must be @samp{unset}, @samp{sdi}, @samp{hdmi},
343 @samp{optical_sdi}, @samp{component}, @samp{composite} or @samp{s_video}.
344 Defaults to @samp{unset}.
347 Sets the audio input source. Must be @samp{unset}, @samp{embedded},
348 @samp{aes_ebu}, @samp{analog}, @samp{analog_xlr}, @samp{analog_rca} or
349 @samp{microphone}. Defaults to @samp{unset}.
352 Sets the video packet timestamp source. Must be @samp{video}, @samp{audio},
353 @samp{reference}, @samp{wallclock} or @samp{abs_wallclock}.
354 Defaults to @samp{video}.
357 Sets the audio packet timestamp source. Must be @samp{video}, @samp{audio},
358 @samp{reference}, @samp{wallclock} or @samp{abs_wallclock}.
359 Defaults to @samp{audio}.
362 If set to @samp{true}, color bars are drawn in the event of a signal loss.
363 Defaults to @samp{true}.
366 Sets maximum input buffer size in bytes. If the buffering reaches this value,
367 incoming frames will be dropped.
368 Defaults to @samp{1073741824}.
371 Sets the audio sample bit depth. Must be @samp{16} or @samp{32}.
372 Defaults to @samp{16}.
374 @item decklink_copyts
375 If set to @option{true}, timestamps are forwarded as they are without removing
377 Defaults to @option{false}.
379 @item timestamp_align
380 Capture start time alignment in seconds. If set to nonzero, input frames are
381 dropped till the system timestamp aligns with configured value.
382 Alignment difference of up to one frame duration is tolerated.
383 This is useful for maintaining input synchronization across N different
384 hardware devices deployed for 'N-way' redundancy. The system time of different
385 hardware devices should be synchronized with protocols such as NTP or PTP,
386 before using this option.
387 Note that this method is not foolproof. In some border cases input
388 synchronization may not happen due to thread scheduling jitters in the OS.
389 Either sync could go wrong by 1 frame or in a rarer case
390 @option{timestamp_align} seconds.
391 Defaults to @samp{0}.
393 @item wait_for_tc (@emph{bool})
394 Drop frames till a frame with timecode is received. Sometimes serial timecode
395 isn't received with the first input frame. If that happens, the stored stream
396 timecode will be inaccurate. If this option is set to @option{true}, input frames
397 are dropped till a frame with timecode is received.
398 Option @var{timecode_format} must be specified.
399 Defaults to @option{false}.
401 @item enable_klv(@emph{bool})
402 If set to @option{true}, extracts KLV data from VANC and outputs KLV packets.
403 KLV VANC packets are joined based on MID and PSC fields and aggregated into
405 Defaults to @option{false}.
416 ffmpeg -sources decklink
420 List supported formats:
422 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
426 Capture video clip at 1080i50:
428 ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -c:a copy -c:v copy output.avi
432 Capture video clip at 1080i50 10 bit:
434 ffmpeg -raw_format yuv422p10 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
438 Capture video clip at 1080i50 with 16 audio channels:
440 ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
447 Windows DirectShow input device.
449 DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
450 Currently only audio and video devices are supported.
452 Multiple devices may be opened as separate inputs, but they may also be
453 opened on the same input, which should improve synchronism between them.
455 The input name should be in the format:
458 @var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
461 where @var{TYPE} can be either @var{audio} or @var{video},
462 and @var{NAME} is the device's name or alternative name..
466 If no options are specified, the device's defaults are used.
467 If the device does not support the requested options, it will
473 Set the video size in the captured video.
476 Set the frame rate in the captured video.
479 Set the sample rate (in Hz) of the captured audio.
482 Set the sample size (in bits) of the captured audio.
485 Set the number of channels in the captured audio.
488 If set to @option{true}, print a list of devices and exit.
491 If set to @option{true}, print a list of selected device's options
494 @item video_device_number
495 Set video device number for devices with the same name (starts at 0,
498 @item audio_device_number
499 Set audio device number for devices with the same name (starts at 0,
503 Select pixel format to be used by DirectShow. This may only be set when
504 the video codec is not set or set to rawvideo.
506 @item audio_buffer_size
507 Set audio device buffer size in milliseconds (which can directly
508 impact latency, depending on the device).
509 Defaults to using the audio device's
510 default buffer size (typically some multiple of 500ms).
511 Setting this value too low can degrade performance.
513 @url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
516 Select video capture pin to use by name or alternative name.
519 Select audio capture pin to use by name or alternative name.
521 @item crossbar_video_input_pin_number
522 Select video input pin number for crossbar device. This will be
523 routed to the crossbar device's Video Decoder output pin.
524 Note that changing this value can affect future invocations
525 (sets a new default) until system reboot occurs.
527 @item crossbar_audio_input_pin_number
528 Select audio input pin number for crossbar device. This will be
529 routed to the crossbar device's Audio Decoder output pin.
530 Note that changing this value can affect future invocations
531 (sets a new default) until system reboot occurs.
533 @item show_video_device_dialog
534 If set to @option{true}, before capture starts, popup a display dialog
535 to the end user, allowing them to change video filter properties
536 and configurations manually.
537 Note that for crossbar devices, adjusting values in this dialog
538 may be needed at times to toggle between PAL (25 fps) and NTSC (29.97)
539 input frame rates, sizes, interlacing, etc. Changing these values can
540 enable different scan rates/frame rates and avoiding green bars at
541 the bottom, flickering scan lines, etc.
542 Note that with some devices, changing these properties can also affect future
543 invocations (sets new defaults) until system reboot occurs.
545 @item show_audio_device_dialog
546 If set to @option{true}, before capture starts, popup a display dialog
547 to the end user, allowing them to change audio filter properties
548 and configurations manually.
550 @item show_video_crossbar_connection_dialog
551 If set to @option{true}, before capture starts, popup a display
552 dialog to the end user, allowing them to manually
553 modify crossbar pin routings, when it opens a video device.
555 @item show_audio_crossbar_connection_dialog
556 If set to @option{true}, before capture starts, popup a display
557 dialog to the end user, allowing them to manually
558 modify crossbar pin routings, when it opens an audio device.
560 @item show_analog_tv_tuner_dialog
561 If set to @option{true}, before capture starts, popup a display
562 dialog to the end user, allowing them to manually
563 modify TV channels and frequencies.
565 @item show_analog_tv_tuner_audio_dialog
566 If set to @option{true}, before capture starts, popup a display
567 dialog to the end user, allowing them to manually
568 modify TV audio (like mono vs. stereo, Language A,B or C).
570 @item audio_device_load
571 Load an audio capture filter device from file instead of searching
572 it by name. It may load additional parameters too, if the filter
573 supports the serialization of its properties to.
574 To use this an audio capture source has to be specified, but it can
575 be anything even fake one.
577 @item audio_device_save
578 Save the currently used audio capture filter device and its
579 parameters (if the filter supports it) to a file.
580 If a file with the same name exists it will be overwritten.
582 @item video_device_load
583 Load a video capture filter device from file instead of searching
584 it by name. It may load additional parameters too, if the filter
585 supports the serialization of its properties to.
586 To use this a video capture source has to be specified, but it can
587 be anything even fake one.
589 @item video_device_save
590 Save the currently used video capture filter device and its
591 parameters (if the filter supports it) to a file.
592 If a file with the same name exists it will be overwritten.
601 Print the list of DirectShow supported devices and exit:
603 $ ffmpeg -list_devices true -f dshow -i dummy
607 Open video device @var{Camera}:
609 $ ffmpeg -f dshow -i video="Camera"
613 Open second video device with name @var{Camera}:
615 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
619 Open video device @var{Camera} and audio device @var{Microphone}:
621 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
625 Print the list of supported options in selected device and exit:
627 $ ffmpeg -list_options true -f dshow -i video="Camera"
631 Specify pin names to capture by name or alternative name, specify alternative device name:
633 $ 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"
637 Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup:
639 $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
640 -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
647 Linux framebuffer input device.
649 The Linux framebuffer is a graphic hardware-independent abstraction
650 layer to show graphics on a computer monitor, typically on the
651 console. It is accessed through a file device node, usually
654 For more detailed information read the file
655 Documentation/fb/framebuffer.txt included in the Linux source tree.
657 See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
659 To record from the framebuffer device @file{/dev/fb0} with
662 ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
665 You can take a single screenshot image with the command:
667 ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
675 Set the frame rate. Default is 25.
681 Win32 GDI-based screen capture device.
683 This device allows you to capture a region of the display on Windows.
685 There are two options for the input filename:
691 title=@var{window_title}
694 The first option will capture the entire desktop, or a fixed region of the
695 desktop. The second option will instead capture the contents of a single
696 window, regardless of its position on the screen.
698 For example, to grab the entire desktop using @command{ffmpeg}:
700 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
703 Grab a 640x480 region at position @code{10,20}:
705 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
708 Grab the contents of the window named "Calculator"
710 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
717 Specify whether to draw the mouse pointer. Use the value @code{0} to
718 not draw the pointer. Default value is @code{1}.
721 Set the grabbing frame rate. Default value is @code{ntsc},
722 corresponding to a frame rate of @code{30000/1001}.
725 Show grabbed region on screen.
727 If @var{show_region} is specified with @code{1}, then the grabbing
728 region will be indicated on screen. With this option, it is easy to
729 know what is being grabbed if only a portion of the screen is grabbed.
731 Note that @var{show_region} is incompatible with grabbing the contents
736 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
740 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.
743 When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
745 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.
748 When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
750 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.
756 FireWire DV/HDV input device using libiec61883.
758 To enable this input device, you need libiec61883, libraw1394 and
759 libavc1394 installed on your system. Use the configure option
760 @code{--enable-libiec61883} to compile with the device enabled.
762 The iec61883 capture device supports capturing from a video device
763 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
764 FireWire stack (juju). This is the default DV/HDV input method in Linux
765 Kernel 2.6.37 and later, since the old FireWire stack was removed.
767 Specify the FireWire port to be used as input file, or "auto"
768 to choose the first port connected.
775 Override autodetection of DV/HDV. This should only be used if auto
776 detection does not work, or if usage of a different device type
777 should be prohibited. Treating a DV device as HDV (or vice versa) will
778 not work and result in undefined behavior.
779 The values @option{auto}, @option{dv} and @option{hdv} are supported.
782 Set maximum size of buffer for incoming data, in frames. For DV, this
783 is an exact value. For HDV, it is not frame exact, since HDV does
784 not have a fixed frame size.
787 Select the capture device by specifying its GUID. Capturing will only
788 be performed from the specified device and fails if no device with the
789 given GUID is found. This is useful to select the input if multiple
790 devices are connected at the same time.
791 Look at /sys/bus/firewire/devices to find out the GUIDs.
800 Grab and show the input of a FireWire DV/HDV device.
802 ffplay -f iec61883 -i auto
806 Grab and record the input of a FireWire DV/HDV device,
807 using a packet buffer of 100000 packets if the source is HDV.
809 ffmpeg -f iec61883 -i auto -dvbuffer 100000 out.mpg
818 To enable this input device during configuration you need libjack
819 installed on your system.
821 A JACK input device creates one or more JACK writable clients, one for
822 each audio channel, with name @var{client_name}:input_@var{N}, where
823 @var{client_name} is the name provided by the application, and @var{N}
824 is a number which identifies the channel.
825 Each writable client will send the acquired data to the FFmpeg input
828 Once you have created one or more JACK readable clients, you need to
829 connect them to one or more JACK writable clients.
831 To connect or disconnect JACK clients you can use the @command{jack_connect}
832 and @command{jack_disconnect} programs, or do it through a graphical interface,
833 for example with @command{qjackctl}.
835 To list the JACK clients and their properties you can invoke the command
838 Follows an example which shows how to capture a JACK readable client
839 with @command{ffmpeg}.
841 # Create a JACK writable client with name "ffmpeg".
842 $ ffmpeg -f jack -i ffmpeg -y out.wav
844 # Start the sample jack_metro readable client.
845 $ jack_metro -b 120 -d 0.2 -f 4000
847 # List the current JACK clients.
856 # Connect metro to the ffmpeg writable client.
857 $ jack_connect metro:120_bpm ffmpeg:input_1
860 For more information read:
861 @url{http://jackaudio.org/}
868 Set the number of channels. Default is 2.
874 KMS video input device.
876 Captures the KMS scanout framebuffer associated with a specified CRTC or plane as a
877 DRM object that can be passed to other hardware functions.
879 Requires either DRM master or CAP_SYS_ADMIN to run.
881 If you don't understand what all of that means, you probably don't want this. Look at
882 @option{x11grab} instead.
889 DRM device to capture on. Defaults to @option{/dev/dri/card0}.
892 Pixel format of the framebuffer. Defaults to @option{bgr0}.
894 @item format_modifier
895 Format modifier to signal on output frames. This is necessary to import correctly into
896 some APIs, but can't be autodetected. See the libdrm documentation for possible values.
899 KMS CRTC ID to define the capture source. The first active plane on the given CRTC
903 KMS plane ID to define the capture source. Defaults to the first active plane found if
904 neither @option{crtc_id} nor @option{plane_id} are specified.
907 Framerate to capture at. This is not synchronised to any page flipping or framebuffer
908 changes - it just defines the interval at which the framebuffer is sampled. Sampling
909 faster than the framebuffer update rate will generate independent frames with the same
910 content. Defaults to @code{30}.
919 Capture from the first active plane, download the result to normal frames and encode.
920 This will only work if the framebuffer is both linear and mappable - if not, the result
921 may be scrambled or fail to download.
923 ffmpeg -f kmsgrab -i - -vf 'hwdownload,format=bgr0' output.mp4
927 Capture from CRTC ID 42 at 60fps, map the result to VAAPI, convert to NV12 and encode as H.264.
929 ffmpeg -crtc_id 42 -framerate 60 -f kmsgrab -i - -vf 'hwmap=derive_device=vaapi,scale_vaapi=w=1920:h=1080:format=nv12' -c:v h264_vaapi output.mp4
933 To capture only part of a plane the output can be cropped - this can be used to capture
934 a single window, as long as it has a known absolute position and size. For example, to
935 capture and encode the middle quarter of a 1920x1080 plane:
937 ffmpeg -f kmsgrab -i - -vf 'hwmap=derive_device=vaapi,crop=960:540:480:270,scale_vaapi=960:540:nv12' -c:v h264_vaapi output.mp4
944 Libavfilter input virtual device.
946 This input device reads data from the open output pads of a libavfilter
949 For each filtergraph open output, the input device will create a
950 corresponding stream which is mapped to the generated output. Currently
951 only video data is supported. The filtergraph is specified through the
952 option @option{graph}.
959 Specify the filtergraph to use as input. Each video open output must be
960 labelled by a unique string of the form "out@var{N}", where @var{N} is a
961 number starting from 0 corresponding to the mapped input stream
962 generated by the device.
963 The first unlabelled output is automatically assigned to the "out0"
964 label, but all the others need to be specified explicitly.
966 The suffix "+subcc" can be appended to the output label to create an extra
967 stream with the closed captions packets attached to that output
968 (experimental; only for EIA-608 / CEA-708 for now).
969 The subcc streams are created after all the normal streams, in the order of
970 the corresponding stream.
971 For example, if there is "out19+subcc", "out7+subcc" and up to "out42", the
972 stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19.
974 If not specified defaults to the filename specified for the input
978 Set the filename of the filtergraph to be read and sent to the other
979 filters. Syntax of the filtergraph is the same as the one specified by
980 the option @var{graph}.
983 Dump graph to stderr.
991 Create a color video stream and play it back with @command{ffplay}:
993 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
997 As the previous example, but use filename for specifying the graph
998 description, and omit the "out0" label:
1000 ffplay -f lavfi color=c=pink
1004 Create three different video test filtered sources and play them:
1006 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
1010 Read an audio stream from a file using the amovie source and play it
1011 back with @command{ffplay}:
1013 ffplay -f lavfi "amovie=test.wav"
1017 Read an audio stream and a video stream and play it back with
1020 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
1024 Dump decoded frames to images and closed captions to a file (experimental):
1026 ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
1033 Audio-CD input device based on libcdio.
1035 To enable this input device during configuration you need libcdio
1036 installed on your system. It requires the configure option
1037 @code{--enable-libcdio}.
1039 This device allows playing and grabbing from an Audio-CD.
1041 For example to copy with @command{ffmpeg} the entire Audio-CD in @file{/dev/sr0},
1042 you may run the command:
1044 ffmpeg -f libcdio -i /dev/sr0 cd.wav
1050 Set drive reading speed. Default value is 0.
1052 The speed is specified CD-ROM speed units. The speed is set through
1053 the libcdio @code{cdio_cddap_speed_set} function. On many CD-ROM
1054 drives, specifying a value too large will result in using the fastest
1058 Set paranoia recovery mode flags. It accepts one of the following values:
1068 Default value is @samp{disable}.
1070 For more information about the available recovery modes, consult the
1071 paranoia project documentation.
1076 IIDC1394 input device, based on libdc1394 and libraw1394.
1078 Requires the configure option @code{--enable-libdc1394}.
1084 Set the frame rate. Default is @code{ntsc}, corresponding to a frame
1085 rate of @code{30000/1001}.
1088 Select the pixel format. Default is @code{uyvy422}.
1091 Set the video size given as a string such as @code{640x480} or @code{hd720}.
1092 Default is @code{qvga}.
1097 The OpenAL input device provides audio capture on all systems with a
1098 working OpenAL 1.1 implementation.
1100 To enable this input device during configuration, you need OpenAL
1101 headers and libraries installed on your system, and need to configure
1102 FFmpeg with @code{--enable-openal}.
1104 OpenAL headers and libraries should be provided as part of your OpenAL
1105 implementation, or as an additional download (an SDK). Depending on your
1106 installation you may need to specify additional flags via the
1107 @code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
1108 system to locate the OpenAL headers and libraries.
1110 An incomplete list of OpenAL implementations follows:
1114 The official Windows implementation, providing hardware acceleration
1115 with supported devices and software fallback.
1116 See @url{http://openal.org/}.
1118 Portable, open source (LGPL) software implementation. Includes
1119 backends for the most common sound APIs on the Windows, Linux,
1120 Solaris, and BSD operating systems.
1121 See @url{http://kcat.strangesoft.net/openal.html}.
1123 OpenAL is part of Core Audio, the official Mac OS X Audio interface.
1124 See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
1127 This device allows one to capture from an audio input device handled
1130 You need to specify the name of the device to capture in the provided
1131 filename. If the empty string is provided, the device will
1132 automatically select the default device. You can get the list of the
1133 supported devices by using the option @var{list_devices}.
1140 Set the number of channels in the captured audio. Only the values
1141 @option{1} (monaural) and @option{2} (stereo) are currently supported.
1142 Defaults to @option{2}.
1145 Set the sample size (in bits) of the captured audio. Only the values
1146 @option{8} and @option{16} are currently supported. Defaults to
1150 Set the sample rate (in Hz) of the captured audio.
1151 Defaults to @option{44.1k}.
1154 If set to @option{true}, print a list of devices and exit.
1155 Defaults to @option{false}.
1159 @subsection Examples
1161 Print the list of OpenAL supported devices and exit:
1163 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
1166 Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
1168 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
1171 Capture from the default device (note the empty string '' as filename):
1173 $ ffmpeg -f openal -i '' out.ogg
1176 Capture from two devices simultaneously, writing to two different files,
1177 within the same @command{ffmpeg} command:
1179 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
1181 Note: not all OpenAL implementations support multiple simultaneous capture -
1182 try the latest OpenAL Soft if the above does not work.
1186 Open Sound System input device.
1188 The filename to provide to the input device is the device node
1189 representing the OSS input device, and is usually set to
1192 For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
1195 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
1198 For more information about OSS see:
1199 @url{http://manuals.opensound.com/usersguide/dsp.html}
1206 Set the sample rate in Hz. Default is 48000.
1209 Set the number of channels. Default is 2.
1215 PulseAudio input device.
1217 To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
1219 The filename to provide to the input device is a source device or the
1222 To list the PulseAudio source devices and their properties you can invoke
1223 the command @command{pactl list sources}.
1225 More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
1230 Connect to a specific PulseAudio server, specified by an IP address.
1231 Default server is used when not provided.
1234 Specify the application name PulseAudio will use when showing active clients,
1235 by default it is the @code{LIBAVFORMAT_IDENT} string.
1238 Specify the stream name PulseAudio will use when showing active streams,
1239 by default it is "record".
1242 Specify the samplerate in Hz, by default 48kHz is used.
1245 Specify the channels in use, by default 2 (stereo) is set.
1248 Specify the number of bytes per frame, by default it is set to 1024.
1251 Specify the minimal buffering fragment in PulseAudio, it will affect the
1252 audio latency. By default it is unset.
1255 Set the initial PTS using the current time. Default is 1.
1259 @subsection Examples
1260 Record a stream from default device:
1262 ffmpeg -f pulse -i default /tmp/pulse.wav
1269 To enable this input device during configuration you need libsndio
1270 installed on your system.
1272 The filename to provide to the input device is the device node
1273 representing the sndio input device, and is usually set to
1276 For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
1279 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
1287 Set the sample rate in Hz. Default is 48000.
1290 Set the number of channels. Default is 2.
1294 @section video4linux2, v4l2
1296 Video4Linux2 input video device.
1298 "v4l2" can be used as alias for "video4linux2".
1300 If FFmpeg is built with v4l-utils support (by using the
1301 @code{--enable-libv4l2} configure option), it is possible to use it with the
1302 @code{-use_libv4l2} input device option.
1304 The name of the device to grab is a file device node, usually Linux
1305 systems tend to automatically create such nodes when the device
1306 (e.g. an USB webcam) is plugged into the system, and has a name of the
1307 kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
1310 Video4Linux2 devices usually support a limited set of
1311 @var{width}x@var{height} sizes and frame rates. You can check which are
1312 supported using @command{-list_formats all} for Video4Linux2 devices.
1313 Some devices, like TV cards, support one or more standards. It is possible
1314 to list all the supported standards using @command{-list_standards all}.
1316 The time base for the timestamps is 1 microsecond. Depending on the kernel
1317 version and configuration, the timestamps may be derived from the real time
1318 clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
1319 boot time, unaffected by NTP or manual changes to the clock). The
1320 @option{-timestamps abs} or @option{-ts abs} option can be used to force
1321 conversion into the real time clock.
1323 Some usage examples of the video4linux2 device with @command{ffmpeg}
1324 and @command{ffplay}:
1327 List supported formats for a video4linux2 device:
1329 ffplay -f video4linux2 -list_formats all /dev/video0
1333 Grab and show the input of a video4linux2 device:
1335 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
1339 Grab and record the input of a video4linux2 device, leave the
1340 frame rate and size as previously set:
1342 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
1346 For more information about Video4Linux, check @url{http://linuxtv.org/}.
1352 Set the standard. Must be the name of a supported standard. To get a
1353 list of the supported standards, use the @option{list_standards}
1357 Set the input channel number. Default to -1, which means using the
1358 previously selected channel.
1361 Set the video frame size. The argument must be a string in the form
1362 @var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
1365 Select the pixel format (only valid for raw video input).
1368 Set the preferred pixel format (for raw video) or a codec name.
1369 This option allows one to select the input format, when several are
1373 Set the preferred video frame rate.
1376 List available formats (supported pixel formats, codecs, and frame
1379 Available values are:
1382 Show all available (compressed and non-compressed) formats.
1385 Show only raw video (non-compressed) formats.
1388 Show only compressed formats.
1391 @item list_standards
1392 List supported standards and exit.
1394 Available values are:
1397 Show all supported standards.
1400 @item timestamps, ts
1401 Set type of timestamps for grabbed frames.
1403 Available values are:
1406 Use timestamps from the kernel.
1409 Use absolute timestamps (wall clock).
1412 Force conversion from monotonic to absolute timestamps.
1415 Default value is @code{default}.
1418 Use libv4l2 (v4l-utils) conversion functions. Default is 0.
1424 VfW (Video for Windows) capture input device.
1426 The filename passed as input is the capture driver number, ranging from
1427 0 to 9. You may use "list" as filename to print a list of drivers. Any
1428 other filename will be interpreted as device number 0.
1435 Set the video frame size.
1438 Set the grabbing frame rate. Default value is @code{ntsc},
1439 corresponding to a frame rate of @code{30000/1001}.
1445 X11 video input device.
1447 To enable this input device during configuration you need libxcb
1448 installed on your system. It will be automatically detected during
1451 This device allows one to capture a region of an X11 display.
1453 The filename passed as input has the syntax:
1455 [@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
1458 @var{hostname}:@var{display_number}.@var{screen_number} specifies the
1459 X11 display name of the screen to grab from. @var{hostname} can be
1460 omitted, and defaults to "localhost". The environment variable
1461 @env{DISPLAY} contains the default display name.
1463 @var{x_offset} and @var{y_offset} specify the offsets of the grabbed
1464 area with respect to the top-left border of the X11 screen. They
1467 Check the X11 documentation (e.g. @command{man X}) for more detailed
1470 Use the @command{xdpyinfo} program for getting basic information about
1471 the properties of your X11 display (e.g. grep for "name" or
1474 For example to grab from @file{:0.0} using @command{ffmpeg}:
1476 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
1479 Grab at position @code{10,20}:
1481 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1488 Specify whether to draw the mouse pointer. A value of @code{0} specifies
1489 not to draw the pointer. Default value is @code{1}.
1492 Make the grabbed area follow the mouse. The argument can be
1493 @code{centered} or a number of pixels @var{PIXELS}.
1495 When it is specified with "centered", the grabbing region follows the mouse
1496 pointer and keeps the pointer at the center of region; otherwise, the region
1497 follows only when the mouse pointer reaches within @var{PIXELS} (greater than
1498 zero) to the edge of region.
1502 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
1505 To follow only when the mouse pointer reaches within 100 pixels to edge:
1507 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
1511 Set the grabbing frame rate. Default value is @code{ntsc},
1512 corresponding to a frame rate of @code{30000/1001}.
1515 Show grabbed region on screen.
1517 If @var{show_region} is specified with @code{1}, then the grabbing
1518 region will be indicated on screen. With this option, it is easy to
1519 know what is being grabbed if only a portion of the screen is grabbed.
1522 Set the region border thickness if @option{-show_region 1} is used.
1523 Range is 1 to 128 and default is 3 (XCB-based x11grab only).
1527 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1530 With @var{follow_mouse}:
1532 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
1536 Set the video frame size. Default is the full desktop.
1540 Set the grabbing region coordinates. They are expressed as offset from
1541 the top left corner of the X11 window and correspond to the
1542 @var{x_offset} and @var{y_offset} parameters in the device name. The
1543 default value for both options is 0.
1546 @c man end INPUT DEVICES