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:
301 This is the default which means 8-bit YUV 422 or 8-bit ARGB if format
302 autodetection is used, 8-bit YUV 422 otherwise.
327 If set to nonzero, an additional teletext stream will be captured from the
328 vertical ancillary data. Both SD PAL (576i) and HD (1080i or 1080p)
329 sources are supported. In case of HD sources, OP47 packets are decoded.
331 This option is a bitmask of the SD PAL VBI lines captured, specifically lines 6
332 to 22, and lines 318 to 335. Line 6 is the LSB in the mask. Selected lines
333 which do not contain teletext information will be ignored. You can use the
334 special @option{all} constant to select all possible lines, or
335 @option{standard} to skip lines 6, 318 and 319, which are not compatible with
338 For SD sources, ffmpeg needs to be compiled with @code{--enable-libzvbi}. For
339 HD sources, on older (pre-4K) DeckLink card models you have to capture in 10
343 Defines number of audio channels to capture. Must be @samp{2}, @samp{8} or @samp{16}.
344 Defaults to @samp{2}.
347 Sets the decklink device duplex mode. Must be @samp{unset}, @samp{half} or @samp{full}.
348 Defaults to @samp{unset}.
350 @item timecode_format
351 Timecode type to include in the frame and video stream metadata. Must be
352 @samp{none}, @samp{rp188vitc}, @samp{rp188vitc2}, @samp{rp188ltc},
353 @samp{rp188hfr}, @samp{rp188any}, @samp{vitc}, @samp{vitc2}, or @samp{serial}.
354 Defaults to @samp{none} (not included).
357 Sets the video input source. Must be @samp{unset}, @samp{sdi}, @samp{hdmi},
358 @samp{optical_sdi}, @samp{component}, @samp{composite} or @samp{s_video}.
359 Defaults to @samp{unset}.
362 Sets the audio input source. Must be @samp{unset}, @samp{embedded},
363 @samp{aes_ebu}, @samp{analog}, @samp{analog_xlr}, @samp{analog_rca} or
364 @samp{microphone}. Defaults to @samp{unset}.
367 Sets the video packet timestamp source. Must be @samp{video}, @samp{audio},
368 @samp{reference}, @samp{wallclock} or @samp{abs_wallclock}.
369 Defaults to @samp{video}.
372 Sets the audio packet timestamp source. Must be @samp{video}, @samp{audio},
373 @samp{reference}, @samp{wallclock} or @samp{abs_wallclock}.
374 Defaults to @samp{audio}.
377 If set to @samp{true}, color bars are drawn in the event of a signal loss.
378 Defaults to @samp{true}.
381 Sets maximum input buffer size in bytes. If the buffering reaches this value,
382 incoming frames will be dropped.
383 Defaults to @samp{1073741824}.
386 Sets the audio sample bit depth. Must be @samp{16} or @samp{32}.
387 Defaults to @samp{16}.
389 @item decklink_copyts
390 If set to @option{true}, timestamps are forwarded as they are without removing
392 Defaults to @option{false}.
394 @item timestamp_align
395 Capture start time alignment in seconds. If set to nonzero, input frames are
396 dropped till the system timestamp aligns with configured value.
397 Alignment difference of up to one frame duration is tolerated.
398 This is useful for maintaining input synchronization across N different
399 hardware devices deployed for 'N-way' redundancy. The system time of different
400 hardware devices should be synchronized with protocols such as NTP or PTP,
401 before using this option.
402 Note that this method is not foolproof. In some border cases input
403 synchronization may not happen due to thread scheduling jitters in the OS.
404 Either sync could go wrong by 1 frame or in a rarer case
405 @option{timestamp_align} seconds.
406 Defaults to @samp{0}.
408 @item wait_for_tc (@emph{bool})
409 Drop frames till a frame with timecode is received. Sometimes serial timecode
410 isn't received with the first input frame. If that happens, the stored stream
411 timecode will be inaccurate. If this option is set to @option{true}, input frames
412 are dropped till a frame with timecode is received.
413 Option @var{timecode_format} must be specified.
414 Defaults to @option{false}.
416 @item enable_klv(@emph{bool})
417 If set to @option{true}, extracts KLV data from VANC and outputs KLV packets.
418 KLV VANC packets are joined based on MID and PSC fields and aggregated into
420 Defaults to @option{false}.
431 ffmpeg -sources decklink
435 List supported formats:
437 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
441 Capture video clip at 1080i50:
443 ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -c:a copy -c:v copy output.avi
447 Capture video clip at 1080i50 10 bit:
449 ffmpeg -raw_format yuv422p10 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
453 Capture video clip at 1080i50 with 16 audio channels:
455 ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
462 Windows DirectShow input device.
464 DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
465 Currently only audio and video devices are supported.
467 Multiple devices may be opened as separate inputs, but they may also be
468 opened on the same input, which should improve synchronism between them.
470 The input name should be in the format:
473 @var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
476 where @var{TYPE} can be either @var{audio} or @var{video},
477 and @var{NAME} is the device's name or alternative name..
481 If no options are specified, the device's defaults are used.
482 If the device does not support the requested options, it will
488 Set the video size in the captured video.
491 Set the frame rate in the captured video.
494 Set the sample rate (in Hz) of the captured audio.
497 Set the sample size (in bits) of the captured audio.
500 Set the number of channels in the captured audio.
503 If set to @option{true}, print a list of devices and exit.
506 If set to @option{true}, print a list of selected device's options
509 @item video_device_number
510 Set video device number for devices with the same name (starts at 0,
513 @item audio_device_number
514 Set audio device number for devices with the same name (starts at 0,
518 Select pixel format to be used by DirectShow. This may only be set when
519 the video codec is not set or set to rawvideo.
521 @item audio_buffer_size
522 Set audio device buffer size in milliseconds (which can directly
523 impact latency, depending on the device).
524 Defaults to using the audio device's
525 default buffer size (typically some multiple of 500ms).
526 Setting this value too low can degrade performance.
528 @url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
531 Select video capture pin to use by name or alternative name.
534 Select audio capture pin to use by name or alternative name.
536 @item crossbar_video_input_pin_number
537 Select video input pin number for crossbar device. This will be
538 routed to the crossbar device's Video Decoder output pin.
539 Note that changing this value can affect future invocations
540 (sets a new default) until system reboot occurs.
542 @item crossbar_audio_input_pin_number
543 Select audio input pin number for crossbar device. This will be
544 routed to the crossbar device's Audio Decoder output pin.
545 Note that changing this value can affect future invocations
546 (sets a new default) until system reboot occurs.
548 @item show_video_device_dialog
549 If set to @option{true}, before capture starts, popup a display dialog
550 to the end user, allowing them to change video filter properties
551 and configurations manually.
552 Note that for crossbar devices, adjusting values in this dialog
553 may be needed at times to toggle between PAL (25 fps) and NTSC (29.97)
554 input frame rates, sizes, interlacing, etc. Changing these values can
555 enable different scan rates/frame rates and avoiding green bars at
556 the bottom, flickering scan lines, etc.
557 Note that with some devices, changing these properties can also affect future
558 invocations (sets new defaults) until system reboot occurs.
560 @item show_audio_device_dialog
561 If set to @option{true}, before capture starts, popup a display dialog
562 to the end user, allowing them to change audio filter properties
563 and configurations manually.
565 @item show_video_crossbar_connection_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 crossbar pin routings, when it opens a video device.
570 @item show_audio_crossbar_connection_dialog
571 If set to @option{true}, before capture starts, popup a display
572 dialog to the end user, allowing them to manually
573 modify crossbar pin routings, when it opens an audio device.
575 @item show_analog_tv_tuner_dialog
576 If set to @option{true}, before capture starts, popup a display
577 dialog to the end user, allowing them to manually
578 modify TV channels and frequencies.
580 @item show_analog_tv_tuner_audio_dialog
581 If set to @option{true}, before capture starts, popup a display
582 dialog to the end user, allowing them to manually
583 modify TV audio (like mono vs. stereo, Language A,B or C).
585 @item audio_device_load
586 Load an audio capture filter device from file instead of searching
587 it by name. It may load additional parameters too, if the filter
588 supports the serialization of its properties to.
589 To use this an audio capture source has to be specified, but it can
590 be anything even fake one.
592 @item audio_device_save
593 Save the currently used audio capture filter device and its
594 parameters (if the filter supports it) to a file.
595 If a file with the same name exists it will be overwritten.
597 @item video_device_load
598 Load a video capture filter device from file instead of searching
599 it by name. It may load additional parameters too, if the filter
600 supports the serialization of its properties to.
601 To use this a video capture source has to be specified, but it can
602 be anything even fake one.
604 @item video_device_save
605 Save the currently used video capture filter device and its
606 parameters (if the filter supports it) to a file.
607 If a file with the same name exists it will be overwritten.
616 Print the list of DirectShow supported devices and exit:
618 $ ffmpeg -list_devices true -f dshow -i dummy
622 Open video device @var{Camera}:
624 $ ffmpeg -f dshow -i video="Camera"
628 Open second video device with name @var{Camera}:
630 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
634 Open video device @var{Camera} and audio device @var{Microphone}:
636 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
640 Print the list of supported options in selected device and exit:
642 $ ffmpeg -list_options true -f dshow -i video="Camera"
646 Specify pin names to capture by name or alternative name, specify alternative device name:
648 $ 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"
652 Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup:
654 $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
655 -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
662 Linux framebuffer input device.
664 The Linux framebuffer is a graphic hardware-independent abstraction
665 layer to show graphics on a computer monitor, typically on the
666 console. It is accessed through a file device node, usually
669 For more detailed information read the file
670 Documentation/fb/framebuffer.txt included in the Linux source tree.
672 See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
674 To record from the framebuffer device @file{/dev/fb0} with
677 ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
680 You can take a single screenshot image with the command:
682 ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
690 Set the frame rate. Default is 25.
696 Win32 GDI-based screen capture device.
698 This device allows you to capture a region of the display on Windows.
700 There are two options for the input filename:
706 title=@var{window_title}
709 The first option will capture the entire desktop, or a fixed region of the
710 desktop. The second option will instead capture the contents of a single
711 window, regardless of its position on the screen.
713 For example, to grab the entire desktop using @command{ffmpeg}:
715 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
718 Grab a 640x480 region at position @code{10,20}:
720 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
723 Grab the contents of the window named "Calculator"
725 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
732 Specify whether to draw the mouse pointer. Use the value @code{0} to
733 not draw the pointer. Default value is @code{1}.
736 Set the grabbing frame rate. Default value is @code{ntsc},
737 corresponding to a frame rate of @code{30000/1001}.
740 Show grabbed region on screen.
742 If @var{show_region} is specified with @code{1}, then the grabbing
743 region will be indicated on screen. With this option, it is easy to
744 know what is being grabbed if only a portion of the screen is grabbed.
746 Note that @var{show_region} is incompatible with grabbing the contents
751 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
755 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.
758 When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
760 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.
763 When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
765 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.
771 FireWire DV/HDV input device using libiec61883.
773 To enable this input device, you need libiec61883, libraw1394 and
774 libavc1394 installed on your system. Use the configure option
775 @code{--enable-libiec61883} to compile with the device enabled.
777 The iec61883 capture device supports capturing from a video device
778 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
779 FireWire stack (juju). This is the default DV/HDV input method in Linux
780 Kernel 2.6.37 and later, since the old FireWire stack was removed.
782 Specify the FireWire port to be used as input file, or "auto"
783 to choose the first port connected.
790 Override autodetection of DV/HDV. This should only be used if auto
791 detection does not work, or if usage of a different device type
792 should be prohibited. Treating a DV device as HDV (or vice versa) will
793 not work and result in undefined behavior.
794 The values @option{auto}, @option{dv} and @option{hdv} are supported.
797 Set maximum size of buffer for incoming data, in frames. For DV, this
798 is an exact value. For HDV, it is not frame exact, since HDV does
799 not have a fixed frame size.
802 Select the capture device by specifying its GUID. Capturing will only
803 be performed from the specified device and fails if no device with the
804 given GUID is found. This is useful to select the input if multiple
805 devices are connected at the same time.
806 Look at /sys/bus/firewire/devices to find out the GUIDs.
815 Grab and show the input of a FireWire DV/HDV device.
817 ffplay -f iec61883 -i auto
821 Grab and record the input of a FireWire DV/HDV device,
822 using a packet buffer of 100000 packets if the source is HDV.
824 ffmpeg -f iec61883 -i auto -dvbuffer 100000 out.mpg
833 To enable this input device during configuration you need libjack
834 installed on your system.
836 A JACK input device creates one or more JACK writable clients, one for
837 each audio channel, with name @var{client_name}:input_@var{N}, where
838 @var{client_name} is the name provided by the application, and @var{N}
839 is a number which identifies the channel.
840 Each writable client will send the acquired data to the FFmpeg input
843 Once you have created one or more JACK readable clients, you need to
844 connect them to one or more JACK writable clients.
846 To connect or disconnect JACK clients you can use the @command{jack_connect}
847 and @command{jack_disconnect} programs, or do it through a graphical interface,
848 for example with @command{qjackctl}.
850 To list the JACK clients and their properties you can invoke the command
853 Follows an example which shows how to capture a JACK readable client
854 with @command{ffmpeg}.
856 # Create a JACK writable client with name "ffmpeg".
857 $ ffmpeg -f jack -i ffmpeg -y out.wav
859 # Start the sample jack_metro readable client.
860 $ jack_metro -b 120 -d 0.2 -f 4000
862 # List the current JACK clients.
871 # Connect metro to the ffmpeg writable client.
872 $ jack_connect metro:120_bpm ffmpeg:input_1
875 For more information read:
876 @url{http://jackaudio.org/}
883 Set the number of channels. Default is 2.
889 KMS video input device.
891 Captures the KMS scanout framebuffer associated with a specified CRTC or plane as a
892 DRM object that can be passed to other hardware functions.
894 Requires either DRM master or CAP_SYS_ADMIN to run.
896 If you don't understand what all of that means, you probably don't want this. Look at
897 @option{x11grab} instead.
904 DRM device to capture on. Defaults to @option{/dev/dri/card0}.
907 Pixel format of the framebuffer. This can be autodetected if you are running Linux 5.7
908 or later, but needs to be provided for earlier versions. Defaults to @option{bgr0},
909 which is the most common format used by the Linux console and Xorg X server.
911 @item format_modifier
912 Format modifier to signal on output frames. This is necessary to import correctly into
913 some APIs. It can be autodetected if you are running Linux 5.7 or later, but will need
914 to be provided explicitly when needed in earlier versions. See the libdrm documentation
918 KMS CRTC ID to define the capture source. The first active plane on the given CRTC
922 KMS plane ID to define the capture source. Defaults to the first active plane found if
923 neither @option{crtc_id} nor @option{plane_id} are specified.
926 Framerate to capture at. This is not synchronised to any page flipping or framebuffer
927 changes - it just defines the interval at which the framebuffer is sampled. Sampling
928 faster than the framebuffer update rate will generate independent frames with the same
929 content. Defaults to @code{30}.
938 Capture from the first active plane, download the result to normal frames and encode.
939 This will only work if the framebuffer is both linear and mappable - if not, the result
940 may be scrambled or fail to download.
942 ffmpeg -f kmsgrab -i - -vf 'hwdownload,format=bgr0' output.mp4
946 Capture from CRTC ID 42 at 60fps, map the result to VAAPI, convert to NV12 and encode as H.264.
948 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
952 To capture only part of a plane the output can be cropped - this can be used to capture
953 a single window, as long as it has a known absolute position and size. For example, to
954 capture and encode the middle quarter of a 1920x1080 plane:
956 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
963 Libavfilter input virtual device.
965 This input device reads data from the open output pads of a libavfilter
968 For each filtergraph open output, the input device will create a
969 corresponding stream which is mapped to the generated output. Currently
970 only video data is supported. The filtergraph is specified through the
971 option @option{graph}.
978 Specify the filtergraph to use as input. Each video open output must be
979 labelled by a unique string of the form "out@var{N}", where @var{N} is a
980 number starting from 0 corresponding to the mapped input stream
981 generated by the device.
982 The first unlabelled output is automatically assigned to the "out0"
983 label, but all the others need to be specified explicitly.
985 The suffix "+subcc" can be appended to the output label to create an extra
986 stream with the closed captions packets attached to that output
987 (experimental; only for EIA-608 / CEA-708 for now).
988 The subcc streams are created after all the normal streams, in the order of
989 the corresponding stream.
990 For example, if there is "out19+subcc", "out7+subcc" and up to "out42", the
991 stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19.
993 If not specified defaults to the filename specified for the input
997 Set the filename of the filtergraph to be read and sent to the other
998 filters. Syntax of the filtergraph is the same as the one specified by
999 the option @var{graph}.
1002 Dump graph to stderr.
1006 @subsection Examples
1010 Create a color video stream and play it back with @command{ffplay}:
1012 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
1016 As the previous example, but use filename for specifying the graph
1017 description, and omit the "out0" label:
1019 ffplay -f lavfi color=c=pink
1023 Create three different video test filtered sources and play them:
1025 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
1029 Read an audio stream from a file using the amovie source and play it
1030 back with @command{ffplay}:
1032 ffplay -f lavfi "amovie=test.wav"
1036 Read an audio stream and a video stream and play it back with
1039 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
1043 Dump decoded frames to images and closed captions to a file (experimental):
1045 ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
1052 Audio-CD input device based on libcdio.
1054 To enable this input device during configuration you need libcdio
1055 installed on your system. It requires the configure option
1056 @code{--enable-libcdio}.
1058 This device allows playing and grabbing from an Audio-CD.
1060 For example to copy with @command{ffmpeg} the entire Audio-CD in @file{/dev/sr0},
1061 you may run the command:
1063 ffmpeg -f libcdio -i /dev/sr0 cd.wav
1069 Set drive reading speed. Default value is 0.
1071 The speed is specified CD-ROM speed units. The speed is set through
1072 the libcdio @code{cdio_cddap_speed_set} function. On many CD-ROM
1073 drives, specifying a value too large will result in using the fastest
1077 Set paranoia recovery mode flags. It accepts one of the following values:
1087 Default value is @samp{disable}.
1089 For more information about the available recovery modes, consult the
1090 paranoia project documentation.
1095 IIDC1394 input device, based on libdc1394 and libraw1394.
1097 Requires the configure option @code{--enable-libdc1394}.
1103 Set the frame rate. Default is @code{ntsc}, corresponding to a frame
1104 rate of @code{30000/1001}.
1107 Select the pixel format. Default is @code{uyvy422}.
1110 Set the video size given as a string such as @code{640x480} or @code{hd720}.
1111 Default is @code{qvga}.
1116 The OpenAL input device provides audio capture on all systems with a
1117 working OpenAL 1.1 implementation.
1119 To enable this input device during configuration, you need OpenAL
1120 headers and libraries installed on your system, and need to configure
1121 FFmpeg with @code{--enable-openal}.
1123 OpenAL headers and libraries should be provided as part of your OpenAL
1124 implementation, or as an additional download (an SDK). Depending on your
1125 installation you may need to specify additional flags via the
1126 @code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
1127 system to locate the OpenAL headers and libraries.
1129 An incomplete list of OpenAL implementations follows:
1133 The official Windows implementation, providing hardware acceleration
1134 with supported devices and software fallback.
1135 See @url{http://openal.org/}.
1137 Portable, open source (LGPL) software implementation. Includes
1138 backends for the most common sound APIs on the Windows, Linux,
1139 Solaris, and BSD operating systems.
1140 See @url{http://kcat.strangesoft.net/openal.html}.
1142 OpenAL is part of Core Audio, the official Mac OS X Audio interface.
1143 See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
1146 This device allows one to capture from an audio input device handled
1149 You need to specify the name of the device to capture in the provided
1150 filename. If the empty string is provided, the device will
1151 automatically select the default device. You can get the list of the
1152 supported devices by using the option @var{list_devices}.
1159 Set the number of channels in the captured audio. Only the values
1160 @option{1} (monaural) and @option{2} (stereo) are currently supported.
1161 Defaults to @option{2}.
1164 Set the sample size (in bits) of the captured audio. Only the values
1165 @option{8} and @option{16} are currently supported. Defaults to
1169 Set the sample rate (in Hz) of the captured audio.
1170 Defaults to @option{44.1k}.
1173 If set to @option{true}, print a list of devices and exit.
1174 Defaults to @option{false}.
1178 @subsection Examples
1180 Print the list of OpenAL supported devices and exit:
1182 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
1185 Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
1187 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
1190 Capture from the default device (note the empty string '' as filename):
1192 $ ffmpeg -f openal -i '' out.ogg
1195 Capture from two devices simultaneously, writing to two different files,
1196 within the same @command{ffmpeg} command:
1198 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
1200 Note: not all OpenAL implementations support multiple simultaneous capture -
1201 try the latest OpenAL Soft if the above does not work.
1205 Open Sound System input device.
1207 The filename to provide to the input device is the device node
1208 representing the OSS input device, and is usually set to
1211 For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
1214 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
1217 For more information about OSS see:
1218 @url{http://manuals.opensound.com/usersguide/dsp.html}
1225 Set the sample rate in Hz. Default is 48000.
1228 Set the number of channels. Default is 2.
1234 PulseAudio input device.
1236 To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
1238 The filename to provide to the input device is a source device or the
1241 To list the PulseAudio source devices and their properties you can invoke
1242 the command @command{pactl list sources}.
1244 More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
1249 Connect to a specific PulseAudio server, specified by an IP address.
1250 Default server is used when not provided.
1253 Specify the application name PulseAudio will use when showing active clients,
1254 by default it is the @code{LIBAVFORMAT_IDENT} string.
1257 Specify the stream name PulseAudio will use when showing active streams,
1258 by default it is "record".
1261 Specify the samplerate in Hz, by default 48kHz is used.
1264 Specify the channels in use, by default 2 (stereo) is set.
1267 Specify the number of bytes per frame, by default it is set to 1024.
1270 Specify the minimal buffering fragment in PulseAudio, it will affect the
1271 audio latency. By default it is unset.
1274 Set the initial PTS using the current time. Default is 1.
1278 @subsection Examples
1279 Record a stream from default device:
1281 ffmpeg -f pulse -i default /tmp/pulse.wav
1288 To enable this input device during configuration you need libsndio
1289 installed on your system.
1291 The filename to provide to the input device is the device node
1292 representing the sndio input device, and is usually set to
1295 For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
1298 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
1306 Set the sample rate in Hz. Default is 48000.
1309 Set the number of channels. Default is 2.
1313 @section video4linux2, v4l2
1315 Video4Linux2 input video device.
1317 "v4l2" can be used as alias for "video4linux2".
1319 If FFmpeg is built with v4l-utils support (by using the
1320 @code{--enable-libv4l2} configure option), it is possible to use it with the
1321 @code{-use_libv4l2} input device option.
1323 The name of the device to grab is a file device node, usually Linux
1324 systems tend to automatically create such nodes when the device
1325 (e.g. an USB webcam) is plugged into the system, and has a name of the
1326 kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
1329 Video4Linux2 devices usually support a limited set of
1330 @var{width}x@var{height} sizes and frame rates. You can check which are
1331 supported using @command{-list_formats all} for Video4Linux2 devices.
1332 Some devices, like TV cards, support one or more standards. It is possible
1333 to list all the supported standards using @command{-list_standards all}.
1335 The time base for the timestamps is 1 microsecond. Depending on the kernel
1336 version and configuration, the timestamps may be derived from the real time
1337 clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
1338 boot time, unaffected by NTP or manual changes to the clock). The
1339 @option{-timestamps abs} or @option{-ts abs} option can be used to force
1340 conversion into the real time clock.
1342 Some usage examples of the video4linux2 device with @command{ffmpeg}
1343 and @command{ffplay}:
1346 List supported formats for a video4linux2 device:
1348 ffplay -f video4linux2 -list_formats all /dev/video0
1352 Grab and show the input of a video4linux2 device:
1354 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
1358 Grab and record the input of a video4linux2 device, leave the
1359 frame rate and size as previously set:
1361 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
1365 For more information about Video4Linux, check @url{http://linuxtv.org/}.
1371 Set the standard. Must be the name of a supported standard. To get a
1372 list of the supported standards, use the @option{list_standards}
1376 Set the input channel number. Default to -1, which means using the
1377 previously selected channel.
1380 Set the video frame size. The argument must be a string in the form
1381 @var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
1384 Select the pixel format (only valid for raw video input).
1387 Set the preferred pixel format (for raw video) or a codec name.
1388 This option allows one to select the input format, when several are
1392 Set the preferred video frame rate.
1395 List available formats (supported pixel formats, codecs, and frame
1398 Available values are:
1401 Show all available (compressed and non-compressed) formats.
1404 Show only raw video (non-compressed) formats.
1407 Show only compressed formats.
1410 @item list_standards
1411 List supported standards and exit.
1413 Available values are:
1416 Show all supported standards.
1419 @item timestamps, ts
1420 Set type of timestamps for grabbed frames.
1422 Available values are:
1425 Use timestamps from the kernel.
1428 Use absolute timestamps (wall clock).
1431 Force conversion from monotonic to absolute timestamps.
1434 Default value is @code{default}.
1437 Use libv4l2 (v4l-utils) conversion functions. Default is 0.
1443 VfW (Video for Windows) capture input device.
1445 The filename passed as input is the capture driver number, ranging from
1446 0 to 9. You may use "list" as filename to print a list of drivers. Any
1447 other filename will be interpreted as device number 0.
1454 Set the video frame size.
1457 Set the grabbing frame rate. Default value is @code{ntsc},
1458 corresponding to a frame rate of @code{30000/1001}.
1464 X11 video input device.
1466 To enable this input device during configuration you need libxcb
1467 installed on your system. It will be automatically detected during
1470 This device allows one to capture a region of an X11 display.
1472 The filename passed as input has the syntax:
1474 [@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
1477 @var{hostname}:@var{display_number}.@var{screen_number} specifies the
1478 X11 display name of the screen to grab from. @var{hostname} can be
1479 omitted, and defaults to "localhost". The environment variable
1480 @env{DISPLAY} contains the default display name.
1482 @var{x_offset} and @var{y_offset} specify the offsets of the grabbed
1483 area with respect to the top-left border of the X11 screen. They
1486 Check the X11 documentation (e.g. @command{man X}) for more detailed
1489 Use the @command{xdpyinfo} program for getting basic information about
1490 the properties of your X11 display (e.g. grep for "name" or
1493 For example to grab from @file{:0.0} using @command{ffmpeg}:
1495 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
1498 Grab at position @code{10,20}:
1500 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1507 Specify whether to select the grabbing area graphically using the pointer.
1508 A value of @code{1} prompts the user to select the grabbing area graphically
1509 by clicking and dragging. A single click with no dragging will select the
1510 whole screen. A region with zero width or height will also select the whole
1511 screen. This option overwrites the @var{video_size}, @var{grab_x}, and
1512 @var{grab_y} options. Default value is @code{0}.
1515 Specify whether to draw the mouse pointer. A value of @code{0} specifies
1516 not to draw the pointer. Default value is @code{1}.
1519 Make the grabbed area follow the mouse. The argument can be
1520 @code{centered} or a number of pixels @var{PIXELS}.
1522 When it is specified with "centered", the grabbing region follows the mouse
1523 pointer and keeps the pointer at the center of region; otherwise, the region
1524 follows only when the mouse pointer reaches within @var{PIXELS} (greater than
1525 zero) to the edge of region.
1529 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
1532 To follow only when the mouse pointer reaches within 100 pixels to edge:
1534 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
1538 Set the grabbing frame rate. Default value is @code{ntsc},
1539 corresponding to a frame rate of @code{30000/1001}.
1542 Show grabbed region on screen.
1544 If @var{show_region} is specified with @code{1}, then the grabbing
1545 region will be indicated on screen. With this option, it is easy to
1546 know what is being grabbed if only a portion of the screen is grabbed.
1549 Set the region border thickness if @option{-show_region 1} is used.
1550 Range is 1 to 128 and default is 3 (XCB-based x11grab only).
1554 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1557 With @var{follow_mouse}:
1559 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
1563 Set the video frame size. Default is the full desktop.
1567 Set the grabbing region coordinates. They are expressed as offset from
1568 the top left corner of the X11 window and correspond to the
1569 @var{x_offset} and @var{y_offset} parameters in the device name. The
1570 default value for both options is 0.
1573 @c man end INPUT DEVICES