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}.
410 ffmpeg -sources decklink
414 List supported formats:
416 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
420 Capture video clip at 1080i50:
422 ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -c:a copy -c:v copy output.avi
426 Capture video clip at 1080i50 10 bit:
428 ffmpeg -raw_format yuv422p10 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
432 Capture video clip at 1080i50 with 16 audio channels:
434 ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
441 Windows DirectShow input device.
443 DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
444 Currently only audio and video devices are supported.
446 Multiple devices may be opened as separate inputs, but they may also be
447 opened on the same input, which should improve synchronism between them.
449 The input name should be in the format:
452 @var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
455 where @var{TYPE} can be either @var{audio} or @var{video},
456 and @var{NAME} is the device's name or alternative name..
460 If no options are specified, the device's defaults are used.
461 If the device does not support the requested options, it will
467 Set the video size in the captured video.
470 Set the frame rate in the captured video.
473 Set the sample rate (in Hz) of the captured audio.
476 Set the sample size (in bits) of the captured audio.
479 Set the number of channels in the captured audio.
482 If set to @option{true}, print a list of devices and exit.
485 If set to @option{true}, print a list of selected device's options
488 @item video_device_number
489 Set video device number for devices with the same name (starts at 0,
492 @item audio_device_number
493 Set audio device number for devices with the same name (starts at 0,
497 Select pixel format to be used by DirectShow. This may only be set when
498 the video codec is not set or set to rawvideo.
500 @item audio_buffer_size
501 Set audio device buffer size in milliseconds (which can directly
502 impact latency, depending on the device).
503 Defaults to using the audio device's
504 default buffer size (typically some multiple of 500ms).
505 Setting this value too low can degrade performance.
507 @url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
510 Select video capture pin to use by name or alternative name.
513 Select audio capture pin to use by name or alternative name.
515 @item crossbar_video_input_pin_number
516 Select video input pin number for crossbar device. This will be
517 routed to the crossbar device's Video Decoder output pin.
518 Note that changing this value can affect future invocations
519 (sets a new default) until system reboot occurs.
521 @item crossbar_audio_input_pin_number
522 Select audio input pin number for crossbar device. This will be
523 routed to the crossbar device's Audio Decoder output pin.
524 Note that changing this value can affect future invocations
525 (sets a new default) until system reboot occurs.
527 @item show_video_device_dialog
528 If set to @option{true}, before capture starts, popup a display dialog
529 to the end user, allowing them to change video filter properties
530 and configurations manually.
531 Note that for crossbar devices, adjusting values in this dialog
532 may be needed at times to toggle between PAL (25 fps) and NTSC (29.97)
533 input frame rates, sizes, interlacing, etc. Changing these values can
534 enable different scan rates/frame rates and avoiding green bars at
535 the bottom, flickering scan lines, etc.
536 Note that with some devices, changing these properties can also affect future
537 invocations (sets new defaults) until system reboot occurs.
539 @item show_audio_device_dialog
540 If set to @option{true}, before capture starts, popup a display dialog
541 to the end user, allowing them to change audio filter properties
542 and configurations manually.
544 @item show_video_crossbar_connection_dialog
545 If set to @option{true}, before capture starts, popup a display
546 dialog to the end user, allowing them to manually
547 modify crossbar pin routings, when it opens a video device.
549 @item show_audio_crossbar_connection_dialog
550 If set to @option{true}, before capture starts, popup a display
551 dialog to the end user, allowing them to manually
552 modify crossbar pin routings, when it opens an audio device.
554 @item show_analog_tv_tuner_dialog
555 If set to @option{true}, before capture starts, popup a display
556 dialog to the end user, allowing them to manually
557 modify TV channels and frequencies.
559 @item show_analog_tv_tuner_audio_dialog
560 If set to @option{true}, before capture starts, popup a display
561 dialog to the end user, allowing them to manually
562 modify TV audio (like mono vs. stereo, Language A,B or C).
564 @item audio_device_load
565 Load an audio capture filter device from file instead of searching
566 it by name. It may load additional parameters too, if the filter
567 supports the serialization of its properties to.
568 To use this an audio capture source has to be specified, but it can
569 be anything even fake one.
571 @item audio_device_save
572 Save the currently used audio capture filter device and its
573 parameters (if the filter supports it) to a file.
574 If a file with the same name exists it will be overwritten.
576 @item video_device_load
577 Load a video capture filter device from file instead of searching
578 it by name. It may load additional parameters too, if the filter
579 supports the serialization of its properties to.
580 To use this a video capture source has to be specified, but it can
581 be anything even fake one.
583 @item video_device_save
584 Save the currently used video capture filter device and its
585 parameters (if the filter supports it) to a file.
586 If a file with the same name exists it will be overwritten.
595 Print the list of DirectShow supported devices and exit:
597 $ ffmpeg -list_devices true -f dshow -i dummy
601 Open video device @var{Camera}:
603 $ ffmpeg -f dshow -i video="Camera"
607 Open second video device with name @var{Camera}:
609 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
613 Open video device @var{Camera} and audio device @var{Microphone}:
615 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
619 Print the list of supported options in selected device and exit:
621 $ ffmpeg -list_options true -f dshow -i video="Camera"
625 Specify pin names to capture by name or alternative name, specify alternative device name:
627 $ 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"
631 Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup:
633 $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
634 -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
641 Linux framebuffer input device.
643 The Linux framebuffer is a graphic hardware-independent abstraction
644 layer to show graphics on a computer monitor, typically on the
645 console. It is accessed through a file device node, usually
648 For more detailed information read the file
649 Documentation/fb/framebuffer.txt included in the Linux source tree.
651 See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
653 To record from the framebuffer device @file{/dev/fb0} with
656 ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
659 You can take a single screenshot image with the command:
661 ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
669 Set the frame rate. Default is 25.
675 Win32 GDI-based screen capture device.
677 This device allows you to capture a region of the display on Windows.
679 There are two options for the input filename:
685 title=@var{window_title}
688 The first option will capture the entire desktop, or a fixed region of the
689 desktop. The second option will instead capture the contents of a single
690 window, regardless of its position on the screen.
692 For example, to grab the entire desktop using @command{ffmpeg}:
694 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
697 Grab a 640x480 region at position @code{10,20}:
699 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
702 Grab the contents of the window named "Calculator"
704 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
711 Specify whether to draw the mouse pointer. Use the value @code{0} to
712 not draw the pointer. Default value is @code{1}.
715 Set the grabbing frame rate. Default value is @code{ntsc},
716 corresponding to a frame rate of @code{30000/1001}.
719 Show grabbed region on screen.
721 If @var{show_region} is specified with @code{1}, then the grabbing
722 region will be indicated on screen. With this option, it is easy to
723 know what is being grabbed if only a portion of the screen is grabbed.
725 Note that @var{show_region} is incompatible with grabbing the contents
730 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
734 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.
737 When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
739 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.
742 When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
744 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.
750 FireWire DV/HDV input device using libiec61883.
752 To enable this input device, you need libiec61883, libraw1394 and
753 libavc1394 installed on your system. Use the configure option
754 @code{--enable-libiec61883} to compile with the device enabled.
756 The iec61883 capture device supports capturing from a video device
757 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
758 FireWire stack (juju). This is the default DV/HDV input method in Linux
759 Kernel 2.6.37 and later, since the old FireWire stack was removed.
761 Specify the FireWire port to be used as input file, or "auto"
762 to choose the first port connected.
769 Override autodetection of DV/HDV. This should only be used if auto
770 detection does not work, or if usage of a different device type
771 should be prohibited. Treating a DV device as HDV (or vice versa) will
772 not work and result in undefined behavior.
773 The values @option{auto}, @option{dv} and @option{hdv} are supported.
776 Set maximum size of buffer for incoming data, in frames. For DV, this
777 is an exact value. For HDV, it is not frame exact, since HDV does
778 not have a fixed frame size.
781 Select the capture device by specifying its GUID. Capturing will only
782 be performed from the specified device and fails if no device with the
783 given GUID is found. This is useful to select the input if multiple
784 devices are connected at the same time.
785 Look at /sys/bus/firewire/devices to find out the GUIDs.
794 Grab and show the input of a FireWire DV/HDV device.
796 ffplay -f iec61883 -i auto
800 Grab and record the input of a FireWire DV/HDV device,
801 using a packet buffer of 100000 packets if the source is HDV.
803 ffmpeg -f iec61883 -i auto -dvbuffer 100000 out.mpg
812 To enable this input device during configuration you need libjack
813 installed on your system.
815 A JACK input device creates one or more JACK writable clients, one for
816 each audio channel, with name @var{client_name}:input_@var{N}, where
817 @var{client_name} is the name provided by the application, and @var{N}
818 is a number which identifies the channel.
819 Each writable client will send the acquired data to the FFmpeg input
822 Once you have created one or more JACK readable clients, you need to
823 connect them to one or more JACK writable clients.
825 To connect or disconnect JACK clients you can use the @command{jack_connect}
826 and @command{jack_disconnect} programs, or do it through a graphical interface,
827 for example with @command{qjackctl}.
829 To list the JACK clients and their properties you can invoke the command
832 Follows an example which shows how to capture a JACK readable client
833 with @command{ffmpeg}.
835 # Create a JACK writable client with name "ffmpeg".
836 $ ffmpeg -f jack -i ffmpeg -y out.wav
838 # Start the sample jack_metro readable client.
839 $ jack_metro -b 120 -d 0.2 -f 4000
841 # List the current JACK clients.
850 # Connect metro to the ffmpeg writable client.
851 $ jack_connect metro:120_bpm ffmpeg:input_1
854 For more information read:
855 @url{http://jackaudio.org/}
862 Set the number of channels. Default is 2.
868 KMS video input device.
870 Captures the KMS scanout framebuffer associated with a specified CRTC or plane as a
871 DRM object that can be passed to other hardware functions.
873 Requires either DRM master or CAP_SYS_ADMIN to run.
875 If you don't understand what all of that means, you probably don't want this. Look at
876 @option{x11grab} instead.
883 DRM device to capture on. Defaults to @option{/dev/dri/card0}.
886 Pixel format of the framebuffer. Defaults to @option{bgr0}.
888 @item format_modifier
889 Format modifier to signal on output frames. This is necessary to import correctly into
890 some APIs, but can't be autodetected. See the libdrm documentation for possible values.
893 KMS CRTC ID to define the capture source. The first active plane on the given CRTC
897 KMS plane ID to define the capture source. Defaults to the first active plane found if
898 neither @option{crtc_id} nor @option{plane_id} are specified.
901 Framerate to capture at. This is not synchronised to any page flipping or framebuffer
902 changes - it just defines the interval at which the framebuffer is sampled. Sampling
903 faster than the framebuffer update rate will generate independent frames with the same
904 content. Defaults to @code{30}.
913 Capture from the first active plane, download the result to normal frames and encode.
914 This will only work if the framebuffer is both linear and mappable - if not, the result
915 may be scrambled or fail to download.
917 ffmpeg -f kmsgrab -i - -vf 'hwdownload,format=bgr0' output.mp4
921 Capture from CRTC ID 42 at 60fps, map the result to VAAPI, convert to NV12 and encode as H.264.
923 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
927 To capture only part of a plane the output can be cropped - this can be used to capture
928 a single window, as long as it has a known absolute position and size. For example, to
929 capture and encode the middle quarter of a 1920x1080 plane:
931 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
938 Libavfilter input virtual device.
940 This input device reads data from the open output pads of a libavfilter
943 For each filtergraph open output, the input device will create a
944 corresponding stream which is mapped to the generated output. Currently
945 only video data is supported. The filtergraph is specified through the
946 option @option{graph}.
953 Specify the filtergraph to use as input. Each video open output must be
954 labelled by a unique string of the form "out@var{N}", where @var{N} is a
955 number starting from 0 corresponding to the mapped input stream
956 generated by the device.
957 The first unlabelled output is automatically assigned to the "out0"
958 label, but all the others need to be specified explicitly.
960 The suffix "+subcc" can be appended to the output label to create an extra
961 stream with the closed captions packets attached to that output
962 (experimental; only for EIA-608 / CEA-708 for now).
963 The subcc streams are created after all the normal streams, in the order of
964 the corresponding stream.
965 For example, if there is "out19+subcc", "out7+subcc" and up to "out42", the
966 stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19.
968 If not specified defaults to the filename specified for the input
972 Set the filename of the filtergraph to be read and sent to the other
973 filters. Syntax of the filtergraph is the same as the one specified by
974 the option @var{graph}.
977 Dump graph to stderr.
985 Create a color video stream and play it back with @command{ffplay}:
987 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
991 As the previous example, but use filename for specifying the graph
992 description, and omit the "out0" label:
994 ffplay -f lavfi color=c=pink
998 Create three different video test filtered sources and play them:
1000 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
1004 Read an audio stream from a file using the amovie source and play it
1005 back with @command{ffplay}:
1007 ffplay -f lavfi "amovie=test.wav"
1011 Read an audio stream and a video stream and play it back with
1014 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
1018 Dump decoded frames to images and closed captions to a file (experimental):
1020 ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
1027 Audio-CD input device based on libcdio.
1029 To enable this input device during configuration you need libcdio
1030 installed on your system. It requires the configure option
1031 @code{--enable-libcdio}.
1033 This device allows playing and grabbing from an Audio-CD.
1035 For example to copy with @command{ffmpeg} the entire Audio-CD in @file{/dev/sr0},
1036 you may run the command:
1038 ffmpeg -f libcdio -i /dev/sr0 cd.wav
1044 Set drive reading speed. Default value is 0.
1046 The speed is specified CD-ROM speed units. The speed is set through
1047 the libcdio @code{cdio_cddap_speed_set} function. On many CD-ROM
1048 drives, specifying a value too large will result in using the fastest
1052 Set paranoia recovery mode flags. It accepts one of the following values:
1062 Default value is @samp{disable}.
1064 For more information about the available recovery modes, consult the
1065 paranoia project documentation.
1070 IIDC1394 input device, based on libdc1394 and libraw1394.
1072 Requires the configure option @code{--enable-libdc1394}.
1078 Set the frame rate. Default is @code{ntsc}, corresponding to a frame
1079 rate of @code{30000/1001}.
1082 Select the pixel format. Default is @code{uyvy422}.
1085 Set the video size given as a string such as @code{640x480} or @code{hd720}.
1086 Default is @code{qvga}.
1091 The OpenAL input device provides audio capture on all systems with a
1092 working OpenAL 1.1 implementation.
1094 To enable this input device during configuration, you need OpenAL
1095 headers and libraries installed on your system, and need to configure
1096 FFmpeg with @code{--enable-openal}.
1098 OpenAL headers and libraries should be provided as part of your OpenAL
1099 implementation, or as an additional download (an SDK). Depending on your
1100 installation you may need to specify additional flags via the
1101 @code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
1102 system to locate the OpenAL headers and libraries.
1104 An incomplete list of OpenAL implementations follows:
1108 The official Windows implementation, providing hardware acceleration
1109 with supported devices and software fallback.
1110 See @url{http://openal.org/}.
1112 Portable, open source (LGPL) software implementation. Includes
1113 backends for the most common sound APIs on the Windows, Linux,
1114 Solaris, and BSD operating systems.
1115 See @url{http://kcat.strangesoft.net/openal.html}.
1117 OpenAL is part of Core Audio, the official Mac OS X Audio interface.
1118 See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
1121 This device allows one to capture from an audio input device handled
1124 You need to specify the name of the device to capture in the provided
1125 filename. If the empty string is provided, the device will
1126 automatically select the default device. You can get the list of the
1127 supported devices by using the option @var{list_devices}.
1134 Set the number of channels in the captured audio. Only the values
1135 @option{1} (monaural) and @option{2} (stereo) are currently supported.
1136 Defaults to @option{2}.
1139 Set the sample size (in bits) of the captured audio. Only the values
1140 @option{8} and @option{16} are currently supported. Defaults to
1144 Set the sample rate (in Hz) of the captured audio.
1145 Defaults to @option{44.1k}.
1148 If set to @option{true}, print a list of devices and exit.
1149 Defaults to @option{false}.
1153 @subsection Examples
1155 Print the list of OpenAL supported devices and exit:
1157 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
1160 Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
1162 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
1165 Capture from the default device (note the empty string '' as filename):
1167 $ ffmpeg -f openal -i '' out.ogg
1170 Capture from two devices simultaneously, writing to two different files,
1171 within the same @command{ffmpeg} command:
1173 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
1175 Note: not all OpenAL implementations support multiple simultaneous capture -
1176 try the latest OpenAL Soft if the above does not work.
1180 Open Sound System input device.
1182 The filename to provide to the input device is the device node
1183 representing the OSS input device, and is usually set to
1186 For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
1189 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
1192 For more information about OSS see:
1193 @url{http://manuals.opensound.com/usersguide/dsp.html}
1200 Set the sample rate in Hz. Default is 48000.
1203 Set the number of channels. Default is 2.
1209 PulseAudio input device.
1211 To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
1213 The filename to provide to the input device is a source device or the
1216 To list the PulseAudio source devices and their properties you can invoke
1217 the command @command{pactl list sources}.
1219 More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
1224 Connect to a specific PulseAudio server, specified by an IP address.
1225 Default server is used when not provided.
1228 Specify the application name PulseAudio will use when showing active clients,
1229 by default it is the @code{LIBAVFORMAT_IDENT} string.
1232 Specify the stream name PulseAudio will use when showing active streams,
1233 by default it is "record".
1236 Specify the samplerate in Hz, by default 48kHz is used.
1239 Specify the channels in use, by default 2 (stereo) is set.
1242 Specify the number of bytes per frame, by default it is set to 1024.
1245 Specify the minimal buffering fragment in PulseAudio, it will affect the
1246 audio latency. By default it is unset.
1249 Set the initial PTS using the current time. Default is 1.
1253 @subsection Examples
1254 Record a stream from default device:
1256 ffmpeg -f pulse -i default /tmp/pulse.wav
1263 To enable this input device during configuration you need libsndio
1264 installed on your system.
1266 The filename to provide to the input device is the device node
1267 representing the sndio input device, and is usually set to
1270 For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
1273 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
1281 Set the sample rate in Hz. Default is 48000.
1284 Set the number of channels. Default is 2.
1288 @section video4linux2, v4l2
1290 Video4Linux2 input video device.
1292 "v4l2" can be used as alias for "video4linux2".
1294 If FFmpeg is built with v4l-utils support (by using the
1295 @code{--enable-libv4l2} configure option), it is possible to use it with the
1296 @code{-use_libv4l2} input device option.
1298 The name of the device to grab is a file device node, usually Linux
1299 systems tend to automatically create such nodes when the device
1300 (e.g. an USB webcam) is plugged into the system, and has a name of the
1301 kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
1304 Video4Linux2 devices usually support a limited set of
1305 @var{width}x@var{height} sizes and frame rates. You can check which are
1306 supported using @command{-list_formats all} for Video4Linux2 devices.
1307 Some devices, like TV cards, support one or more standards. It is possible
1308 to list all the supported standards using @command{-list_standards all}.
1310 The time base for the timestamps is 1 microsecond. Depending on the kernel
1311 version and configuration, the timestamps may be derived from the real time
1312 clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
1313 boot time, unaffected by NTP or manual changes to the clock). The
1314 @option{-timestamps abs} or @option{-ts abs} option can be used to force
1315 conversion into the real time clock.
1317 Some usage examples of the video4linux2 device with @command{ffmpeg}
1318 and @command{ffplay}:
1321 List supported formats for a video4linux2 device:
1323 ffplay -f video4linux2 -list_formats all /dev/video0
1327 Grab and show the input of a video4linux2 device:
1329 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
1333 Grab and record the input of a video4linux2 device, leave the
1334 frame rate and size as previously set:
1336 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
1340 For more information about Video4Linux, check @url{http://linuxtv.org/}.
1346 Set the standard. Must be the name of a supported standard. To get a
1347 list of the supported standards, use the @option{list_standards}
1351 Set the input channel number. Default to -1, which means using the
1352 previously selected channel.
1355 Set the video frame size. The argument must be a string in the form
1356 @var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
1359 Select the pixel format (only valid for raw video input).
1362 Set the preferred pixel format (for raw video) or a codec name.
1363 This option allows one to select the input format, when several are
1367 Set the preferred video frame rate.
1370 List available formats (supported pixel formats, codecs, and frame
1373 Available values are:
1376 Show all available (compressed and non-compressed) formats.
1379 Show only raw video (non-compressed) formats.
1382 Show only compressed formats.
1385 @item list_standards
1386 List supported standards and exit.
1388 Available values are:
1391 Show all supported standards.
1394 @item timestamps, ts
1395 Set type of timestamps for grabbed frames.
1397 Available values are:
1400 Use timestamps from the kernel.
1403 Use absolute timestamps (wall clock).
1406 Force conversion from monotonic to absolute timestamps.
1409 Default value is @code{default}.
1412 Use libv4l2 (v4l-utils) conversion functions. Default is 0.
1418 VfW (Video for Windows) capture input device.
1420 The filename passed as input is the capture driver number, ranging from
1421 0 to 9. You may use "list" as filename to print a list of drivers. Any
1422 other filename will be interpreted as device number 0.
1429 Set the video frame size.
1432 Set the grabbing frame rate. Default value is @code{ntsc},
1433 corresponding to a frame rate of @code{30000/1001}.
1439 X11 video input device.
1441 To enable this input device during configuration you need libxcb
1442 installed on your system. It will be automatically detected during
1445 This device allows one to capture a region of an X11 display.
1447 The filename passed as input has the syntax:
1449 [@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
1452 @var{hostname}:@var{display_number}.@var{screen_number} specifies the
1453 X11 display name of the screen to grab from. @var{hostname} can be
1454 omitted, and defaults to "localhost". The environment variable
1455 @env{DISPLAY} contains the default display name.
1457 @var{x_offset} and @var{y_offset} specify the offsets of the grabbed
1458 area with respect to the top-left border of the X11 screen. They
1461 Check the X11 documentation (e.g. @command{man X}) for more detailed
1464 Use the @command{xdpyinfo} program for getting basic information about
1465 the properties of your X11 display (e.g. grep for "name" or
1468 For example to grab from @file{:0.0} using @command{ffmpeg}:
1470 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
1473 Grab at position @code{10,20}:
1475 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1482 Specify whether to draw the mouse pointer. A value of @code{0} specifies
1483 not to draw the pointer. Default value is @code{1}.
1486 Make the grabbed area follow the mouse. The argument can be
1487 @code{centered} or a number of pixels @var{PIXELS}.
1489 When it is specified with "centered", the grabbing region follows the mouse
1490 pointer and keeps the pointer at the center of region; otherwise, the region
1491 follows only when the mouse pointer reaches within @var{PIXELS} (greater than
1492 zero) to the edge of region.
1496 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
1499 To follow only when the mouse pointer reaches within 100 pixels to edge:
1501 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
1505 Set the grabbing frame rate. Default value is @code{ntsc},
1506 corresponding to a frame rate of @code{30000/1001}.
1509 Show grabbed region on screen.
1511 If @var{show_region} is specified with @code{1}, then the grabbing
1512 region will be indicated on screen. With this option, it is easy to
1513 know what is being grabbed if only a portion of the screen is grabbed.
1516 Set the region border thickness if @option{-show_region 1} is used.
1517 Range is 1 to 128 and default is 3 (XCB-based x11grab only).
1521 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1524 With @var{follow_mouse}:
1526 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
1530 Set the video frame size. Default is the full desktop.
1534 Set the grabbing region coordinates. They are expressed as offset from
1535 the top left corner of the X11 window and correspond to the
1536 @var{x_offset} and @var{y_offset} parameters in the device name. The
1537 default value for both options is 0.
1540 @c man end INPUT DEVICES