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.
188 Print the list of AVFoundation supported devices and exit:
190 $ ffmpeg -f avfoundation -list_devices true -i ""
194 Record video from video device 0 and audio from audio device 0 into out.avi:
196 $ ffmpeg -f avfoundation -i "0:0" out.avi
200 Record video from video device 2 and audio from audio device 1 into out.avi:
202 $ ffmpeg -f avfoundation -video_device_index 2 -i ":1" out.avi
206 Record video from the system default video device using the pixel format bgr0 and do not record any audio into out.avi:
208 $ ffmpeg -f avfoundation -pixel_format bgr0 -i "default:none" out.avi
215 BSD video input device.
225 Set the video frame size. Default is @code{vga}.
229 Available values are:
249 The decklink input device provides capture capabilities for Blackmagic
252 To enable this input device, you need the Blackmagic DeckLink SDK and you
253 need to configure with the appropriate @code{--extra-cflags}
254 and @code{--extra-ldflags}.
255 On Windows, you need to run the IDL files through @command{widl}.
257 DeckLink is very picky about the formats it supports. Pixel format of the
258 input can be set with @option{raw_format}.
259 Framerate and video size must be determined for your device with
260 @command{-list_formats 1}. Audio sample rate is always 48 kHz and the number
261 of channels can be 2, 8 or 16. Note that all audio channels are bundled in one single
269 If set to @option{true}, print a list of devices and exit.
270 Defaults to @option{false}. Alternatively you can use the @code{-sources}
271 option of ffmpeg to list the available input devices.
274 If set to @option{true}, print a list of supported formats and exit.
275 Defaults to @option{false}.
277 @item format_code <FourCC>
278 This sets the input video format to the format given by the FourCC. To see
279 the supported values of your device(s) use @option{list_formats}.
280 Note that there is a FourCC @option{'pal '} that can also be used
281 as @option{pal} (3 letters).
282 Default behavior is autodetection of the input video format, if the hardware
286 This is a deprecated option, you can use @option{raw_format} instead.
287 If set to @samp{1}, video is captured in 10 bit v210 instead
288 of uyvy422. Not all Blackmagic devices support this option.
291 Set the pixel format of the captured video.
292 Available values are:
307 If set to nonzero, an additional teletext stream will be captured from the
308 vertical ancillary data. Both SD PAL (576i) and HD (1080i or 1080p)
309 sources are supported. In case of HD sources, OP47 packets are decoded.
311 This option is a bitmask of the SD PAL VBI lines captured, specifically lines 6
312 to 22, and lines 318 to 335. Line 6 is the LSB in the mask. Selected lines
313 which do not contain teletext information will be ignored. You can use the
314 special @option{all} constant to select all possible lines, or
315 @option{standard} to skip lines 6, 318 and 319, which are not compatible with
318 For SD sources, ffmpeg needs to be compiled with @code{--enable-libzvbi}. For
319 HD sources, on older (pre-4K) DeckLink card models you have to capture in 10
323 Defines number of audio channels to capture. Must be @samp{2}, @samp{8} or @samp{16}.
324 Defaults to @samp{2}.
327 Sets the decklink device duplex mode. Must be @samp{unset}, @samp{half} or @samp{full}.
328 Defaults to @samp{unset}.
330 @item timecode_format
331 Timecode type to include in the frame and video stream metadata. Must be
332 @samp{none}, @samp{rp188vitc}, @samp{rp188vitc2}, @samp{rp188ltc},
333 @samp{rp188any}, @samp{vitc}, @samp{vitc2}, or @samp{serial}. Defaults to
334 @samp{none} (not included).
337 Sets the video input source. Must be @samp{unset}, @samp{sdi}, @samp{hdmi},
338 @samp{optical_sdi}, @samp{component}, @samp{composite} or @samp{s_video}.
339 Defaults to @samp{unset}.
342 Sets the audio input source. Must be @samp{unset}, @samp{embedded},
343 @samp{aes_ebu}, @samp{analog}, @samp{analog_xlr}, @samp{analog_rca} or
344 @samp{microphone}. Defaults to @samp{unset}.
347 Sets the video packet timestamp source. Must be @samp{video}, @samp{audio},
348 @samp{reference}, @samp{wallclock} or @samp{abs_wallclock}.
349 Defaults to @samp{video}.
352 Sets the audio packet timestamp source. Must be @samp{video}, @samp{audio},
353 @samp{reference}, @samp{wallclock} or @samp{abs_wallclock}.
354 Defaults to @samp{audio}.
357 If set to @samp{true}, color bars are drawn in the event of a signal loss.
358 Defaults to @samp{true}.
361 Sets maximum input buffer size in bytes. If the buffering reaches this value,
362 incoming frames will be dropped.
363 Defaults to @samp{1073741824}.
366 Sets the audio sample bit depth. Must be @samp{16} or @samp{32}.
367 Defaults to @samp{16}.
369 @item decklink_copyts
370 If set to @option{true}, timestamps are forwarded as they are without removing
372 Defaults to @option{false}.
374 @item timestamp_align
375 Capture start time alignment in seconds. If set to nonzero, input frames are
376 dropped till the system timestamp aligns with configured value.
377 Alignment difference of upto one frame duration is tolerated.
378 This is useful for maintaining input synchronization across N different
379 hardware devices deployed for 'N-way' redundancy. The system time of different
380 hardware devices should be synchronized with protocols such as NTP or PTP,
381 before using this option.
382 Note that this method is not foolproof. In some border cases input
383 synchronization may not happen due to thread scheduling jitters in the OS.
384 Either sync could go wrong by 1 frame or in a rarer case
385 @option{timestamp_align} seconds.
386 Defaults to @samp{0}.
397 ffmpeg -f decklink -list_devices 1 -i dummy
401 List supported formats:
403 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
407 Capture video clip at 1080i50:
409 ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -c:a copy -c:v copy output.avi
413 Capture video clip at 1080i50 10 bit:
415 ffmpeg -bm_v210 1 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
419 Capture video clip at 1080i50 with 16 audio channels:
421 ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
428 Windows DirectShow input device.
430 DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
431 Currently only audio and video devices are supported.
433 Multiple devices may be opened as separate inputs, but they may also be
434 opened on the same input, which should improve synchronism between them.
436 The input name should be in the format:
439 @var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
442 where @var{TYPE} can be either @var{audio} or @var{video},
443 and @var{NAME} is the device's name or alternative name..
447 If no options are specified, the device's defaults are used.
448 If the device does not support the requested options, it will
454 Set the video size in the captured video.
457 Set the frame rate in the captured video.
460 Set the sample rate (in Hz) of the captured audio.
463 Set the sample size (in bits) of the captured audio.
466 Set the number of channels in the captured audio.
469 If set to @option{true}, print a list of devices and exit.
472 If set to @option{true}, print a list of selected device's options
475 @item video_device_number
476 Set video device number for devices with the same name (starts at 0,
479 @item audio_device_number
480 Set audio device number for devices with the same name (starts at 0,
484 Select pixel format to be used by DirectShow. This may only be set when
485 the video codec is not set or set to rawvideo.
487 @item audio_buffer_size
488 Set audio device buffer size in milliseconds (which can directly
489 impact latency, depending on the device).
490 Defaults to using the audio device's
491 default buffer size (typically some multiple of 500ms).
492 Setting this value too low can degrade performance.
494 @url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
497 Select video capture pin to use by name or alternative name.
500 Select audio capture pin to use by name or alternative name.
502 @item crossbar_video_input_pin_number
503 Select video input pin number for crossbar device. This will be
504 routed to the crossbar device's Video Decoder output pin.
505 Note that changing this value can affect future invocations
506 (sets a new default) until system reboot occurs.
508 @item crossbar_audio_input_pin_number
509 Select audio input pin number for crossbar device. This will be
510 routed to the crossbar device's Audio Decoder output pin.
511 Note that changing this value can affect future invocations
512 (sets a new default) until system reboot occurs.
514 @item show_video_device_dialog
515 If set to @option{true}, before capture starts, popup a display dialog
516 to the end user, allowing them to change video filter properties
517 and configurations manually.
518 Note that for crossbar devices, adjusting values in this dialog
519 may be needed at times to toggle between PAL (25 fps) and NTSC (29.97)
520 input frame rates, sizes, interlacing, etc. Changing these values can
521 enable different scan rates/frame rates and avoiding green bars at
522 the bottom, flickering scan lines, etc.
523 Note that with some devices, changing these properties can also affect future
524 invocations (sets new defaults) until system reboot occurs.
526 @item show_audio_device_dialog
527 If set to @option{true}, before capture starts, popup a display dialog
528 to the end user, allowing them to change audio filter properties
529 and configurations manually.
531 @item show_video_crossbar_connection_dialog
532 If set to @option{true}, before capture starts, popup a display
533 dialog to the end user, allowing them to manually
534 modify crossbar pin routings, when it opens a video device.
536 @item show_audio_crossbar_connection_dialog
537 If set to @option{true}, before capture starts, popup a display
538 dialog to the end user, allowing them to manually
539 modify crossbar pin routings, when it opens an audio device.
541 @item show_analog_tv_tuner_dialog
542 If set to @option{true}, before capture starts, popup a display
543 dialog to the end user, allowing them to manually
544 modify TV channels and frequencies.
546 @item show_analog_tv_tuner_audio_dialog
547 If set to @option{true}, before capture starts, popup a display
548 dialog to the end user, allowing them to manually
549 modify TV audio (like mono vs. stereo, Language A,B or C).
551 @item audio_device_load
552 Load an audio capture filter device from file instead of searching
553 it by name. It may load additional parameters too, if the filter
554 supports the serialization of its properties to.
555 To use this an audio capture source has to be specified, but it can
556 be anything even fake one.
558 @item audio_device_save
559 Save the currently used audio capture filter device and its
560 parameters (if the filter supports it) to a file.
561 If a file with the same name exists it will be overwritten.
563 @item video_device_load
564 Load a video capture filter device from file instead of searching
565 it by name. It may load additional parameters too, if the filter
566 supports the serialization of its properties to.
567 To use this a video capture source has to be specified, but it can
568 be anything even fake one.
570 @item video_device_save
571 Save the currently used video capture filter device and its
572 parameters (if the filter supports it) to a file.
573 If a file with the same name exists it will be overwritten.
582 Print the list of DirectShow supported devices and exit:
584 $ ffmpeg -list_devices true -f dshow -i dummy
588 Open video device @var{Camera}:
590 $ ffmpeg -f dshow -i video="Camera"
594 Open second video device with name @var{Camera}:
596 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
600 Open video device @var{Camera} and audio device @var{Microphone}:
602 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
606 Print the list of supported options in selected device and exit:
608 $ ffmpeg -list_options true -f dshow -i video="Camera"
612 Specify pin names to capture by name or alternative name, specify alternative device name:
614 $ 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"
618 Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup:
620 $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
621 -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
628 Linux framebuffer input device.
630 The Linux framebuffer is a graphic hardware-independent abstraction
631 layer to show graphics on a computer monitor, typically on the
632 console. It is accessed through a file device node, usually
635 For more detailed information read the file
636 Documentation/fb/framebuffer.txt included in the Linux source tree.
638 See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
640 To record from the framebuffer device @file{/dev/fb0} with
643 ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
646 You can take a single screenshot image with the command:
648 ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
656 Set the frame rate. Default is 25.
662 Win32 GDI-based screen capture device.
664 This device allows you to capture a region of the display on Windows.
666 There are two options for the input filename:
672 title=@var{window_title}
675 The first option will capture the entire desktop, or a fixed region of the
676 desktop. The second option will instead capture the contents of a single
677 window, regardless of its position on the screen.
679 For example, to grab the entire desktop using @command{ffmpeg}:
681 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
684 Grab a 640x480 region at position @code{10,20}:
686 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
689 Grab the contents of the window named "Calculator"
691 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
698 Specify whether to draw the mouse pointer. Use the value @code{0} to
699 not draw the pointer. Default value is @code{1}.
702 Set the grabbing frame rate. Default value is @code{ntsc},
703 corresponding to a frame rate of @code{30000/1001}.
706 Show grabbed region on screen.
708 If @var{show_region} is specified with @code{1}, then the grabbing
709 region will be indicated on screen. With this option, it is easy to
710 know what is being grabbed if only a portion of the screen is grabbed.
712 Note that @var{show_region} is incompatible with grabbing the contents
717 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
721 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.
724 When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
726 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.
729 When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
731 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.
737 FireWire DV/HDV input device using libiec61883.
739 To enable this input device, you need libiec61883, libraw1394 and
740 libavc1394 installed on your system. Use the configure option
741 @code{--enable-libiec61883} to compile with the device enabled.
743 The iec61883 capture device supports capturing from a video device
744 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
745 FireWire stack (juju). This is the default DV/HDV input method in Linux
746 Kernel 2.6.37 and later, since the old FireWire stack was removed.
748 Specify the FireWire port to be used as input file, or "auto"
749 to choose the first port connected.
756 Override autodetection of DV/HDV. This should only be used if auto
757 detection does not work, or if usage of a different device type
758 should be prohibited. Treating a DV device as HDV (or vice versa) will
759 not work and result in undefined behavior.
760 The values @option{auto}, @option{dv} and @option{hdv} are supported.
763 Set maximum size of buffer for incoming data, in frames. For DV, this
764 is an exact value. For HDV, it is not frame exact, since HDV does
765 not have a fixed frame size.
768 Select the capture device by specifying its GUID. Capturing will only
769 be performed from the specified device and fails if no device with the
770 given GUID is found. This is useful to select the input if multiple
771 devices are connected at the same time.
772 Look at /sys/bus/firewire/devices to find out the GUIDs.
781 Grab and show the input of a FireWire DV/HDV device.
783 ffplay -f iec61883 -i auto
787 Grab and record the input of a FireWire DV/HDV device,
788 using a packet buffer of 100000 packets if the source is HDV.
790 ffmpeg -f iec61883 -i auto -hdvbuffer 100000 out.mpg
799 To enable this input device during configuration you need libjack
800 installed on your system.
802 A JACK input device creates one or more JACK writable clients, one for
803 each audio channel, with name @var{client_name}:input_@var{N}, where
804 @var{client_name} is the name provided by the application, and @var{N}
805 is a number which identifies the channel.
806 Each writable client will send the acquired data to the FFmpeg input
809 Once you have created one or more JACK readable clients, you need to
810 connect them to one or more JACK writable clients.
812 To connect or disconnect JACK clients you can use the @command{jack_connect}
813 and @command{jack_disconnect} programs, or do it through a graphical interface,
814 for example with @command{qjackctl}.
816 To list the JACK clients and their properties you can invoke the command
819 Follows an example which shows how to capture a JACK readable client
820 with @command{ffmpeg}.
822 # Create a JACK writable client with name "ffmpeg".
823 $ ffmpeg -f jack -i ffmpeg -y out.wav
825 # Start the sample jack_metro readable client.
826 $ jack_metro -b 120 -d 0.2 -f 4000
828 # List the current JACK clients.
837 # Connect metro to the ffmpeg writable client.
838 $ jack_connect metro:120_bpm ffmpeg:input_1
841 For more information read:
842 @url{http://jackaudio.org/}
849 Set the number of channels. Default is 2.
855 KMS video input device.
857 Captures the KMS scanout framebuffer associated with a specified CRTC or plane as a
858 DRM object that can be passed to other hardware functions.
860 Requires either DRM master or CAP_SYS_ADMIN to run.
862 If you don't understand what all of that means, you probably don't want this. Look at
863 @option{x11grab} instead.
870 DRM device to capture on. Defaults to @option{/dev/dri/card0}.
873 Pixel format of the framebuffer. Defaults to @option{bgr0}.
875 @item format_modifier
876 Format modifier to signal on output frames. This is necessary to import correctly into
877 some APIs, but can't be autodetected. See the libdrm documentation for possible values.
880 KMS CRTC ID to define the capture source. The first active plane on the given CRTC
884 KMS plane ID to define the capture source. Defaults to the first active plane found if
885 neither @option{crtc_id} nor @option{plane_id} are specified.
888 Framerate to capture at. This is not synchronised to any page flipping or framebuffer
889 changes - it just defines the interval at which the framebuffer is sampled. Sampling
890 faster than the framebuffer update rate will generate independent frames with the same
891 content. Defaults to @code{30}.
900 Capture from the first active plane, download the result to normal frames and encode.
901 This will only work if the framebuffer is both linear and mappable - if not, the result
902 may be scrambled or fail to download.
904 ffmpeg -f kmsgrab -i - -vf 'hwdownload,format=bgr0' output.mp4
908 Capture from CRTC ID 42 at 60fps, map the result to VAAPI, convert to NV12 and encode as H.264.
910 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
917 Libavfilter input virtual device.
919 This input device reads data from the open output pads of a libavfilter
922 For each filtergraph open output, the input device will create a
923 corresponding stream which is mapped to the generated output. Currently
924 only video data is supported. The filtergraph is specified through the
925 option @option{graph}.
932 Specify the filtergraph to use as input. Each video open output must be
933 labelled by a unique string of the form "out@var{N}", where @var{N} is a
934 number starting from 0 corresponding to the mapped input stream
935 generated by the device.
936 The first unlabelled output is automatically assigned to the "out0"
937 label, but all the others need to be specified explicitly.
939 The suffix "+subcc" can be appended to the output label to create an extra
940 stream with the closed captions packets attached to that output
941 (experimental; only for EIA-608 / CEA-708 for now).
942 The subcc streams are created after all the normal streams, in the order of
943 the corresponding stream.
944 For example, if there is "out19+subcc", "out7+subcc" and up to "out42", the
945 stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19.
947 If not specified defaults to the filename specified for the input
951 Set the filename of the filtergraph to be read and sent to the other
952 filters. Syntax of the filtergraph is the same as the one specified by
953 the option @var{graph}.
956 Dump graph to stderr.
964 Create a color video stream and play it back with @command{ffplay}:
966 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
970 As the previous example, but use filename for specifying the graph
971 description, and omit the "out0" label:
973 ffplay -f lavfi color=c=pink
977 Create three different video test filtered sources and play them:
979 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
983 Read an audio stream from a file using the amovie source and play it
984 back with @command{ffplay}:
986 ffplay -f lavfi "amovie=test.wav"
990 Read an audio stream and a video stream and play it back with
993 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
997 Dump decoded frames to images and closed captions to a file (experimental):
999 ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
1006 Audio-CD input device based on libcdio.
1008 To enable this input device during configuration you need libcdio
1009 installed on your system. It requires the configure option
1010 @code{--enable-libcdio}.
1012 This device allows playing and grabbing from an Audio-CD.
1014 For example to copy with @command{ffmpeg} the entire Audio-CD in @file{/dev/sr0},
1015 you may run the command:
1017 ffmpeg -f libcdio -i /dev/sr0 cd.wav
1023 Set drive reading speed. Default value is 0.
1025 The speed is specified CD-ROM speed units. The speed is set through
1026 the libcdio @code{cdio_cddap_speed_set} function. On many CD-ROM
1027 drives, specifying a value too large will result in using the fastest
1031 Set paranoia recovery mode flags. It accepts one of the following values:
1041 Default value is @samp{disable}.
1043 For more information about the available recovery modes, consult the
1044 paranoia project documentation.
1049 IIDC1394 input device, based on libdc1394 and libraw1394.
1051 Requires the configure option @code{--enable-libdc1394}.
1053 @section libndi_newtek
1055 The libndi_newtek input device provides capture capabilities for using NDI (Network
1056 Device Interface, standard created by NewTek).
1058 Input filename is a NDI source name that could be found by sending -find_sources 1
1059 to command line - it has no specific syntax but human-readable formatted.
1061 To enable this input device, you need the NDI SDK and you
1062 need to configure with the appropriate @code{--extra-cflags}
1063 and @code{--extra-ldflags}.
1070 If set to @option{true}, print a list of found/available NDI sources and exit.
1071 Defaults to @option{false}.
1074 Override time to wait until the number of online sources have changed.
1075 Defaults to @option{0.5}.
1077 @item allow_video_fields
1078 When this flag is @option{false}, all video that you receive will be progressive.
1079 Defaults to @option{true}.
1083 @subsection Examples
1090 ffmpeg -f libndi_newtek -find_sources 1 -i dummy
1096 ffmpeg -f libndi_newtek -i "DEV-5.INTERNAL.M1STEREO.TV (NDI_SOURCE_NAME_1)" -f libndi_newtek -y NDI_SOURCE_NAME_2
1103 The OpenAL input device provides audio capture on all systems with a
1104 working OpenAL 1.1 implementation.
1106 To enable this input device during configuration, you need OpenAL
1107 headers and libraries installed on your system, and need to configure
1108 FFmpeg with @code{--enable-openal}.
1110 OpenAL headers and libraries should be provided as part of your OpenAL
1111 implementation, or as an additional download (an SDK). Depending on your
1112 installation you may need to specify additional flags via the
1113 @code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
1114 system to locate the OpenAL headers and libraries.
1116 An incomplete list of OpenAL implementations follows:
1120 The official Windows implementation, providing hardware acceleration
1121 with supported devices and software fallback.
1122 See @url{http://openal.org/}.
1124 Portable, open source (LGPL) software implementation. Includes
1125 backends for the most common sound APIs on the Windows, Linux,
1126 Solaris, and BSD operating systems.
1127 See @url{http://kcat.strangesoft.net/openal.html}.
1129 OpenAL is part of Core Audio, the official Mac OS X Audio interface.
1130 See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
1133 This device allows one to capture from an audio input device handled
1136 You need to specify the name of the device to capture in the provided
1137 filename. If the empty string is provided, the device will
1138 automatically select the default device. You can get the list of the
1139 supported devices by using the option @var{list_devices}.
1146 Set the number of channels in the captured audio. Only the values
1147 @option{1} (monaural) and @option{2} (stereo) are currently supported.
1148 Defaults to @option{2}.
1151 Set the sample size (in bits) of the captured audio. Only the values
1152 @option{8} and @option{16} are currently supported. Defaults to
1156 Set the sample rate (in Hz) of the captured audio.
1157 Defaults to @option{44.1k}.
1160 If set to @option{true}, print a list of devices and exit.
1161 Defaults to @option{false}.
1165 @subsection Examples
1167 Print the list of OpenAL supported devices and exit:
1169 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
1172 Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
1174 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
1177 Capture from the default device (note the empty string '' as filename):
1179 $ ffmpeg -f openal -i '' out.ogg
1182 Capture from two devices simultaneously, writing to two different files,
1183 within the same @command{ffmpeg} command:
1185 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
1187 Note: not all OpenAL implementations support multiple simultaneous capture -
1188 try the latest OpenAL Soft if the above does not work.
1192 Open Sound System input device.
1194 The filename to provide to the input device is the device node
1195 representing the OSS input device, and is usually set to
1198 For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
1201 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
1204 For more information about OSS see:
1205 @url{http://manuals.opensound.com/usersguide/dsp.html}
1212 Set the sample rate in Hz. Default is 48000.
1215 Set the number of channels. Default is 2.
1221 PulseAudio input device.
1223 To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
1225 The filename to provide to the input device is a source device or the
1228 To list the PulseAudio source devices and their properties you can invoke
1229 the command @command{pactl list sources}.
1231 More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
1236 Connect to a specific PulseAudio server, specified by an IP address.
1237 Default server is used when not provided.
1240 Specify the application name PulseAudio will use when showing active clients,
1241 by default it is the @code{LIBAVFORMAT_IDENT} string.
1244 Specify the stream name PulseAudio will use when showing active streams,
1245 by default it is "record".
1248 Specify the samplerate in Hz, by default 48kHz is used.
1251 Specify the channels in use, by default 2 (stereo) is set.
1254 Specify the number of bytes per frame, by default it is set to 1024.
1257 Specify the minimal buffering fragment in PulseAudio, it will affect the
1258 audio latency. By default it is unset.
1261 Set the initial PTS using the current time. Default is 1.
1265 @subsection Examples
1266 Record a stream from default device:
1268 ffmpeg -f pulse -i default /tmp/pulse.wav
1275 To enable this input device during configuration you need libsndio
1276 installed on your system.
1278 The filename to provide to the input device is the device node
1279 representing the sndio input device, and is usually set to
1282 For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
1285 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
1293 Set the sample rate in Hz. Default is 48000.
1296 Set the number of channels. Default is 2.
1300 @section video4linux2, v4l2
1302 Video4Linux2 input video device.
1304 "v4l2" can be used as alias for "video4linux2".
1306 If FFmpeg is built with v4l-utils support (by using the
1307 @code{--enable-libv4l2} configure option), it is possible to use it with the
1308 @code{-use_libv4l2} input device option.
1310 The name of the device to grab is a file device node, usually Linux
1311 systems tend to automatically create such nodes when the device
1312 (e.g. an USB webcam) is plugged into the system, and has a name of the
1313 kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
1316 Video4Linux2 devices usually support a limited set of
1317 @var{width}x@var{height} sizes and frame rates. You can check which are
1318 supported using @command{-list_formats all} for Video4Linux2 devices.
1319 Some devices, like TV cards, support one or more standards. It is possible
1320 to list all the supported standards using @command{-list_standards all}.
1322 The time base for the timestamps is 1 microsecond. Depending on the kernel
1323 version and configuration, the timestamps may be derived from the real time
1324 clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
1325 boot time, unaffected by NTP or manual changes to the clock). The
1326 @option{-timestamps abs} or @option{-ts abs} option can be used to force
1327 conversion into the real time clock.
1329 Some usage examples of the video4linux2 device with @command{ffmpeg}
1330 and @command{ffplay}:
1333 List supported formats for a video4linux2 device:
1335 ffplay -f video4linux2 -list_formats all /dev/video0
1339 Grab and show the input of a video4linux2 device:
1341 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
1345 Grab and record the input of a video4linux2 device, leave the
1346 frame rate and size as previously set:
1348 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
1352 For more information about Video4Linux, check @url{http://linuxtv.org/}.
1358 Set the standard. Must be the name of a supported standard. To get a
1359 list of the supported standards, use the @option{list_standards}
1363 Set the input channel number. Default to -1, which means using the
1364 previously selected channel.
1367 Set the video frame size. The argument must be a string in the form
1368 @var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
1371 Select the pixel format (only valid for raw video input).
1374 Set the preferred pixel format (for raw video) or a codec name.
1375 This option allows one to select the input format, when several are
1379 Set the preferred video frame rate.
1382 List available formats (supported pixel formats, codecs, and frame
1385 Available values are:
1388 Show all available (compressed and non-compressed) formats.
1391 Show only raw video (non-compressed) formats.
1394 Show only compressed formats.
1397 @item list_standards
1398 List supported standards and exit.
1400 Available values are:
1403 Show all supported standards.
1406 @item timestamps, ts
1407 Set type of timestamps for grabbed frames.
1409 Available values are:
1412 Use timestamps from the kernel.
1415 Use absolute timestamps (wall clock).
1418 Force conversion from monotonic to absolute timestamps.
1421 Default value is @code{default}.
1424 Use libv4l2 (v4l-utils) conversion functions. Default is 0.
1430 VfW (Video for Windows) capture input device.
1432 The filename passed as input is the capture driver number, ranging from
1433 0 to 9. You may use "list" as filename to print a list of drivers. Any
1434 other filename will be interpreted as device number 0.
1441 Set the video frame size.
1444 Set the grabbing frame rate. Default value is @code{ntsc},
1445 corresponding to a frame rate of @code{30000/1001}.
1451 X11 video input device.
1453 To enable this input device during configuration you need libxcb
1454 installed on your system. It will be automatically detected during
1457 This device allows one to capture a region of an X11 display.
1459 The filename passed as input has the syntax:
1461 [@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
1464 @var{hostname}:@var{display_number}.@var{screen_number} specifies the
1465 X11 display name of the screen to grab from. @var{hostname} can be
1466 omitted, and defaults to "localhost". The environment variable
1467 @env{DISPLAY} contains the default display name.
1469 @var{x_offset} and @var{y_offset} specify the offsets of the grabbed
1470 area with respect to the top-left border of the X11 screen. They
1473 Check the X11 documentation (e.g. @command{man X}) for more detailed
1476 Use the @command{xdpyinfo} program for getting basic information about
1477 the properties of your X11 display (e.g. grep for "name" or
1480 For example to grab from @file{:0.0} using @command{ffmpeg}:
1482 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
1485 Grab at position @code{10,20}:
1487 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1494 Specify whether to draw the mouse pointer. A value of @code{0} specifies
1495 not to draw the pointer. Default value is @code{1}.
1498 Make the grabbed area follow the mouse. The argument can be
1499 @code{centered} or a number of pixels @var{PIXELS}.
1501 When it is specified with "centered", the grabbing region follows the mouse
1502 pointer and keeps the pointer at the center of region; otherwise, the region
1503 follows only when the mouse pointer reaches within @var{PIXELS} (greater than
1504 zero) to the edge of region.
1508 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
1511 To follow only when the mouse pointer reaches within 100 pixels to edge:
1513 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
1517 Set the grabbing frame rate. Default value is @code{ntsc},
1518 corresponding to a frame rate of @code{30000/1001}.
1521 Show grabbed region on screen.
1523 If @var{show_region} is specified with @code{1}, then the grabbing
1524 region will be indicated on screen. With this option, it is easy to
1525 know what is being grabbed if only a portion of the screen is grabbed.
1528 Set the region border thickness if @option{-show_region 1} is used.
1529 Range is 1 to 128 and default is 3 (XCB-based x11grab only).
1533 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1536 With @var{follow_mouse}:
1538 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
1542 Set the video frame size. Default value is @code{vga}.
1546 Set the grabbing region coordinates. They are expressed as offset from
1547 the top left corner of the X11 window and correspond to the
1548 @var{x_offset} and @var{y_offset} parameters in the device name. The
1549 default value for both options is 0.
1552 @c man end INPUT DEVICES