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}.
273 If set to @option{true}, print a list of supported formats and exit.
274 Defaults to @option{false}.
276 @item format_code <FourCC>
277 This sets the input video format to the format given by the FourCC. To see
278 the supported values of your device(s) use @option{list_formats}.
279 Note that there is a FourCC @option{'pal '} that can also be used
280 as @option{pal} (3 letters).
281 Default behavior is autodetection of the input video format, if the hardware
285 This is a deprecated option, you can use @option{raw_format} instead.
286 If set to @samp{1}, video is captured in 10 bit v210 instead
287 of uyvy422. Not all Blackmagic devices support this option.
290 Set the pixel format of the captured video.
291 Available values are:
306 If set to nonzero, an additional teletext stream will be captured from the
307 vertical ancillary data. Both SD PAL (576i) and HD (1080i or 1080p)
308 sources are supported. In case of HD sources, OP47 packets are decoded.
310 This option is a bitmask of the SD PAL VBI lines captured, specifically lines 6
311 to 22, and lines 318 to 335. Line 6 is the LSB in the mask. Selected lines
312 which do not contain teletext information will be ignored. You can use the
313 special @option{all} constant to select all possible lines, or
314 @option{standard} to skip lines 6, 318 and 319, which are not compatible with
317 For SD sources, ffmpeg needs to be compiled with @code{--enable-libzvbi}. For
318 HD sources, on older (pre-4K) DeckLink card models you have to capture in 10
322 Defines number of audio channels to capture. Must be @samp{2}, @samp{8} or @samp{16}.
323 Defaults to @samp{2}.
326 Sets the decklink device duplex mode. Must be @samp{unset}, @samp{half} or @samp{full}.
327 Defaults to @samp{unset}.
330 Sets the video input source. Must be @samp{unset}, @samp{sdi}, @samp{hdmi},
331 @samp{optical_sdi}, @samp{component}, @samp{composite} or @samp{s_video}.
332 Defaults to @samp{unset}.
335 Sets the audio input source. Must be @samp{unset}, @samp{embedded},
336 @samp{aes_ebu}, @samp{analog}, @samp{analog_xlr}, @samp{analog_rca} or
337 @samp{microphone}. Defaults to @samp{unset}.
340 Sets the video packet timestamp source. Must be @samp{video}, @samp{audio},
341 @samp{reference}, @samp{wallclock} or @samp{abs_wallclock}.
342 Defaults to @samp{video}.
345 Sets the audio packet timestamp source. Must be @samp{video}, @samp{audio},
346 @samp{reference}, @samp{wallclock} or @samp{abs_wallclock}.
347 Defaults to @samp{audio}.
350 If set to @samp{true}, color bars are drawn in the event of a signal loss.
351 Defaults to @samp{true}.
354 Sets maximum input buffer size in bytes. If the buffering reaches this value,
355 incoming frames will be dropped.
356 Defaults to @samp{1073741824}.
359 Sets the audio sample bit depth. Must be @samp{16} or @samp{32}.
360 Defaults to @samp{16}.
362 @item decklink_copyts
363 If set to @option{true}, timestamps are forwarded as they are without removing
365 Defaults to @option{false}.
376 ffmpeg -f decklink -list_devices 1 -i dummy
380 List supported formats:
382 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
386 Capture video clip at 1080i50:
388 ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -c:a copy -c:v copy output.avi
392 Capture video clip at 1080i50 10 bit:
394 ffmpeg -bm_v210 1 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
398 Capture video clip at 1080i50 with 16 audio channels:
400 ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
407 KMS video input device.
409 Captures the KMS scanout framebuffer associated with a specified CRTC or plane as a
410 DRM object that can be passed to other hardware functions.
412 Requires either DRM master or CAP_SYS_ADMIN to run.
414 If you don't understand what all of that means, you probably don't want this. Look at
415 @option{x11grab} instead.
422 DRM device to capture on. Defaults to @option{/dev/dri/card0}.
425 Pixel format of the framebuffer. Defaults to @option{bgr0}.
427 @item format_modifier
428 Format modifier to signal on output frames. This is necessary to import correctly into
429 some APIs, but can't be autodetected. See the libdrm documentation for possible values.
432 KMS CRTC ID to define the capture source. The first active plane on the given CRTC
436 KMS plane ID to define the capture source. Defaults to the first active plane found if
437 neither @option{crtc_id} nor @option{plane_id} are specified.
440 Framerate to capture at. This is not synchronised to any page flipping or framebuffer
441 changes - it just defines the interval at which the framebuffer is sampled. Sampling
442 faster than the framebuffer update rate will generate independent frames with the same
443 content. Defaults to @code{30}.
452 Capture from the first active plane, download the result to normal frames and encode.
453 This will only work if the framebuffer is both linear and mappable - if not, the result
454 may be scrambled or fail to download.
456 ffmpeg -f kmsgrab -i - -vf 'hwdownload,format=bgr0' output.mp4
460 Capture from CRTC ID 42 at 60fps, map the result to VAAPI, convert to NV12 and encode as H.264.
462 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
467 @section libndi_newtek
469 The libndi_newtek input device provides capture capabilities for using NDI (Network
470 Device Interface, standard created by NewTek).
472 Input filename is a NDI source name that could be found by sending -find_sources 1
473 to command line - it has no specific syntax but human-readable formatted.
475 To enable this input device, you need the NDI SDK and you
476 need to configure with the appropriate @code{--extra-cflags}
477 and @code{--extra-ldflags}.
484 If set to @option{true}, print a list of found/available NDI sources and exit.
485 Defaults to @option{false}.
488 Override time to wait until the number of online sources have changed.
489 Defaults to @option{0.5}.
491 @item allow_video_fields
492 When this flag is @option{false}, all video that you receive will be progressive.
493 Defaults to @option{true}.
504 ffmpeg -f libndi_newtek -find_sources 1 -i dummy
510 ffmpeg -f libndi_newtek -i "DEV-5.INTERNAL.M1STEREO.TV (NDI_SOURCE_NAME_1)" -f libndi_newtek -y NDI_SOURCE_NAME_2
517 Windows DirectShow input device.
519 DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
520 Currently only audio and video devices are supported.
522 Multiple devices may be opened as separate inputs, but they may also be
523 opened on the same input, which should improve synchronism between them.
525 The input name should be in the format:
528 @var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
531 where @var{TYPE} can be either @var{audio} or @var{video},
532 and @var{NAME} is the device's name or alternative name..
536 If no options are specified, the device's defaults are used.
537 If the device does not support the requested options, it will
543 Set the video size in the captured video.
546 Set the frame rate in the captured video.
549 Set the sample rate (in Hz) of the captured audio.
552 Set the sample size (in bits) of the captured audio.
555 Set the number of channels in the captured audio.
558 If set to @option{true}, print a list of devices and exit.
561 If set to @option{true}, print a list of selected device's options
564 @item video_device_number
565 Set video device number for devices with the same name (starts at 0,
568 @item audio_device_number
569 Set audio device number for devices with the same name (starts at 0,
573 Select pixel format to be used by DirectShow. This may only be set when
574 the video codec is not set or set to rawvideo.
576 @item audio_buffer_size
577 Set audio device buffer size in milliseconds (which can directly
578 impact latency, depending on the device).
579 Defaults to using the audio device's
580 default buffer size (typically some multiple of 500ms).
581 Setting this value too low can degrade performance.
583 @url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
586 Select video capture pin to use by name or alternative name.
589 Select audio capture pin to use by name or alternative name.
591 @item crossbar_video_input_pin_number
592 Select video input pin number for crossbar device. This will be
593 routed to the crossbar device's Video Decoder output pin.
594 Note that changing this value can affect future invocations
595 (sets a new default) until system reboot occurs.
597 @item crossbar_audio_input_pin_number
598 Select audio input pin number for crossbar device. This will be
599 routed to the crossbar device's Audio Decoder output pin.
600 Note that changing this value can affect future invocations
601 (sets a new default) until system reboot occurs.
603 @item show_video_device_dialog
604 If set to @option{true}, before capture starts, popup a display dialog
605 to the end user, allowing them to change video filter properties
606 and configurations manually.
607 Note that for crossbar devices, adjusting values in this dialog
608 may be needed at times to toggle between PAL (25 fps) and NTSC (29.97)
609 input frame rates, sizes, interlacing, etc. Changing these values can
610 enable different scan rates/frame rates and avoiding green bars at
611 the bottom, flickering scan lines, etc.
612 Note that with some devices, changing these properties can also affect future
613 invocations (sets new defaults) until system reboot occurs.
615 @item show_audio_device_dialog
616 If set to @option{true}, before capture starts, popup a display dialog
617 to the end user, allowing them to change audio filter properties
618 and configurations manually.
620 @item show_video_crossbar_connection_dialog
621 If set to @option{true}, before capture starts, popup a display
622 dialog to the end user, allowing them to manually
623 modify crossbar pin routings, when it opens a video device.
625 @item show_audio_crossbar_connection_dialog
626 If set to @option{true}, before capture starts, popup a display
627 dialog to the end user, allowing them to manually
628 modify crossbar pin routings, when it opens an audio device.
630 @item show_analog_tv_tuner_dialog
631 If set to @option{true}, before capture starts, popup a display
632 dialog to the end user, allowing them to manually
633 modify TV channels and frequencies.
635 @item show_analog_tv_tuner_audio_dialog
636 If set to @option{true}, before capture starts, popup a display
637 dialog to the end user, allowing them to manually
638 modify TV audio (like mono vs. stereo, Language A,B or C).
640 @item audio_device_load
641 Load an audio capture filter device from file instead of searching
642 it by name. It may load additional parameters too, if the filter
643 supports the serialization of its properties to.
644 To use this an audio capture source has to be specified, but it can
645 be anything even fake one.
647 @item audio_device_save
648 Save the currently used audio capture filter device and its
649 parameters (if the filter supports it) to a file.
650 If a file with the same name exists it will be overwritten.
652 @item video_device_load
653 Load a video capture filter device from file instead of searching
654 it by name. It may load additional parameters too, if the filter
655 supports the serialization of its properties to.
656 To use this a video capture source has to be specified, but it can
657 be anything even fake one.
659 @item video_device_save
660 Save the currently used video capture filter device and its
661 parameters (if the filter supports it) to a file.
662 If a file with the same name exists it will be overwritten.
671 Print the list of DirectShow supported devices and exit:
673 $ ffmpeg -list_devices true -f dshow -i dummy
677 Open video device @var{Camera}:
679 $ ffmpeg -f dshow -i video="Camera"
683 Open second video device with name @var{Camera}:
685 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
689 Open video device @var{Camera} and audio device @var{Microphone}:
691 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
695 Print the list of supported options in selected device and exit:
697 $ ffmpeg -list_options true -f dshow -i video="Camera"
701 Specify pin names to capture by name or alternative name, specify alternative device name:
703 $ 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"
707 Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup:
709 $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
710 -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
717 Linux framebuffer input device.
719 The Linux framebuffer is a graphic hardware-independent abstraction
720 layer to show graphics on a computer monitor, typically on the
721 console. It is accessed through a file device node, usually
724 For more detailed information read the file
725 Documentation/fb/framebuffer.txt included in the Linux source tree.
727 See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
729 To record from the framebuffer device @file{/dev/fb0} with
732 ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
735 You can take a single screenshot image with the command:
737 ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
745 Set the frame rate. Default is 25.
751 Win32 GDI-based screen capture device.
753 This device allows you to capture a region of the display on Windows.
755 There are two options for the input filename:
761 title=@var{window_title}
764 The first option will capture the entire desktop, or a fixed region of the
765 desktop. The second option will instead capture the contents of a single
766 window, regardless of its position on the screen.
768 For example, to grab the entire desktop using @command{ffmpeg}:
770 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
773 Grab a 640x480 region at position @code{10,20}:
775 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
778 Grab the contents of the window named "Calculator"
780 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
787 Specify whether to draw the mouse pointer. Use the value @code{0} to
788 not draw the pointer. Default value is @code{1}.
791 Set the grabbing frame rate. Default value is @code{ntsc},
792 corresponding to a frame rate of @code{30000/1001}.
795 Show grabbed region on screen.
797 If @var{show_region} is specified with @code{1}, then the grabbing
798 region will be indicated on screen. With this option, it is easy to
799 know what is being grabbed if only a portion of the screen is grabbed.
801 Note that @var{show_region} is incompatible with grabbing the contents
806 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
810 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.
813 When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
815 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.
818 When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
820 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.
826 FireWire DV/HDV input device using libiec61883.
828 To enable this input device, you need libiec61883, libraw1394 and
829 libavc1394 installed on your system. Use the configure option
830 @code{--enable-libiec61883} to compile with the device enabled.
832 The iec61883 capture device supports capturing from a video device
833 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
834 FireWire stack (juju). This is the default DV/HDV input method in Linux
835 Kernel 2.6.37 and later, since the old FireWire stack was removed.
837 Specify the FireWire port to be used as input file, or "auto"
838 to choose the first port connected.
845 Override autodetection of DV/HDV. This should only be used if auto
846 detection does not work, or if usage of a different device type
847 should be prohibited. Treating a DV device as HDV (or vice versa) will
848 not work and result in undefined behavior.
849 The values @option{auto}, @option{dv} and @option{hdv} are supported.
852 Set maximum size of buffer for incoming data, in frames. For DV, this
853 is an exact value. For HDV, it is not frame exact, since HDV does
854 not have a fixed frame size.
857 Select the capture device by specifying its GUID. Capturing will only
858 be performed from the specified device and fails if no device with the
859 given GUID is found. This is useful to select the input if multiple
860 devices are connected at the same time.
861 Look at /sys/bus/firewire/devices to find out the GUIDs.
870 Grab and show the input of a FireWire DV/HDV device.
872 ffplay -f iec61883 -i auto
876 Grab and record the input of a FireWire DV/HDV device,
877 using a packet buffer of 100000 packets if the source is HDV.
879 ffmpeg -f iec61883 -i auto -hdvbuffer 100000 out.mpg
888 To enable this input device during configuration you need libjack
889 installed on your system.
891 A JACK input device creates one or more JACK writable clients, one for
892 each audio channel, with name @var{client_name}:input_@var{N}, where
893 @var{client_name} is the name provided by the application, and @var{N}
894 is a number which identifies the channel.
895 Each writable client will send the acquired data to the FFmpeg input
898 Once you have created one or more JACK readable clients, you need to
899 connect them to one or more JACK writable clients.
901 To connect or disconnect JACK clients you can use the @command{jack_connect}
902 and @command{jack_disconnect} programs, or do it through a graphical interface,
903 for example with @command{qjackctl}.
905 To list the JACK clients and their properties you can invoke the command
908 Follows an example which shows how to capture a JACK readable client
909 with @command{ffmpeg}.
911 # Create a JACK writable client with name "ffmpeg".
912 $ ffmpeg -f jack -i ffmpeg -y out.wav
914 # Start the sample jack_metro readable client.
915 $ jack_metro -b 120 -d 0.2 -f 4000
917 # List the current JACK clients.
926 # Connect metro to the ffmpeg writable client.
927 $ jack_connect metro:120_bpm ffmpeg:input_1
930 For more information read:
931 @url{http://jackaudio.org/}
938 Set the number of channels. Default is 2.
944 Libavfilter input virtual device.
946 This input device reads data from the open output pads of a libavfilter
949 For each filtergraph open output, the input device will create a
950 corresponding stream which is mapped to the generated output. Currently
951 only video data is supported. The filtergraph is specified through the
952 option @option{graph}.
959 Specify the filtergraph to use as input. Each video open output must be
960 labelled by a unique string of the form "out@var{N}", where @var{N} is a
961 number starting from 0 corresponding to the mapped input stream
962 generated by the device.
963 The first unlabelled output is automatically assigned to the "out0"
964 label, but all the others need to be specified explicitly.
966 The suffix "+subcc" can be appended to the output label to create an extra
967 stream with the closed captions packets attached to that output
968 (experimental; only for EIA-608 / CEA-708 for now).
969 The subcc streams are created after all the normal streams, in the order of
970 the corresponding stream.
971 For example, if there is "out19+subcc", "out7+subcc" and up to "out42", the
972 stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19.
974 If not specified defaults to the filename specified for the input
978 Set the filename of the filtergraph to be read and sent to the other
979 filters. Syntax of the filtergraph is the same as the one specified by
980 the option @var{graph}.
983 Dump graph to stderr.
991 Create a color video stream and play it back with @command{ffplay}:
993 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
997 As the previous example, but use filename for specifying the graph
998 description, and omit the "out0" label:
1000 ffplay -f lavfi color=c=pink
1004 Create three different video test filtered sources and play them:
1006 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
1010 Read an audio stream from a file using the amovie source and play it
1011 back with @command{ffplay}:
1013 ffplay -f lavfi "amovie=test.wav"
1017 Read an audio stream and a video stream and play it back with
1020 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
1024 Dump decoded frames to images and closed captions to a file (experimental):
1026 ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
1033 Audio-CD input device based on libcdio.
1035 To enable this input device during configuration you need libcdio
1036 installed on your system. It requires the configure option
1037 @code{--enable-libcdio}.
1039 This device allows playing and grabbing from an Audio-CD.
1041 For example to copy with @command{ffmpeg} the entire Audio-CD in @file{/dev/sr0},
1042 you may run the command:
1044 ffmpeg -f libcdio -i /dev/sr0 cd.wav
1050 Set drive reading speed. Default value is 0.
1052 The speed is specified CD-ROM speed units. The speed is set through
1053 the libcdio @code{cdio_cddap_speed_set} function. On many CD-ROM
1054 drives, specifying a value too large will result in using the fastest
1058 Set paranoia recovery mode flags. It accepts one of the following values:
1068 Default value is @samp{disable}.
1070 For more information about the available recovery modes, consult the
1071 paranoia project documentation.
1076 IIDC1394 input device, based on libdc1394 and libraw1394.
1078 Requires the configure option @code{--enable-libdc1394}.
1082 The OpenAL input device provides audio capture on all systems with a
1083 working OpenAL 1.1 implementation.
1085 To enable this input device during configuration, you need OpenAL
1086 headers and libraries installed on your system, and need to configure
1087 FFmpeg with @code{--enable-openal}.
1089 OpenAL headers and libraries should be provided as part of your OpenAL
1090 implementation, or as an additional download (an SDK). Depending on your
1091 installation you may need to specify additional flags via the
1092 @code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
1093 system to locate the OpenAL headers and libraries.
1095 An incomplete list of OpenAL implementations follows:
1099 The official Windows implementation, providing hardware acceleration
1100 with supported devices and software fallback.
1101 See @url{http://openal.org/}.
1103 Portable, open source (LGPL) software implementation. Includes
1104 backends for the most common sound APIs on the Windows, Linux,
1105 Solaris, and BSD operating systems.
1106 See @url{http://kcat.strangesoft.net/openal.html}.
1108 OpenAL is part of Core Audio, the official Mac OS X Audio interface.
1109 See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
1112 This device allows one to capture from an audio input device handled
1115 You need to specify the name of the device to capture in the provided
1116 filename. If the empty string is provided, the device will
1117 automatically select the default device. You can get the list of the
1118 supported devices by using the option @var{list_devices}.
1125 Set the number of channels in the captured audio. Only the values
1126 @option{1} (monaural) and @option{2} (stereo) are currently supported.
1127 Defaults to @option{2}.
1130 Set the sample size (in bits) of the captured audio. Only the values
1131 @option{8} and @option{16} are currently supported. Defaults to
1135 Set the sample rate (in Hz) of the captured audio.
1136 Defaults to @option{44.1k}.
1139 If set to @option{true}, print a list of devices and exit.
1140 Defaults to @option{false}.
1144 @subsection Examples
1146 Print the list of OpenAL supported devices and exit:
1148 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
1151 Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
1153 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
1156 Capture from the default device (note the empty string '' as filename):
1158 $ ffmpeg -f openal -i '' out.ogg
1161 Capture from two devices simultaneously, writing to two different files,
1162 within the same @command{ffmpeg} command:
1164 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
1166 Note: not all OpenAL implementations support multiple simultaneous capture -
1167 try the latest OpenAL Soft if the above does not work.
1171 Open Sound System input device.
1173 The filename to provide to the input device is the device node
1174 representing the OSS input device, and is usually set to
1177 For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
1180 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
1183 For more information about OSS see:
1184 @url{http://manuals.opensound.com/usersguide/dsp.html}
1191 Set the sample rate in Hz. Default is 48000.
1194 Set the number of channels. Default is 2.
1201 PulseAudio input device.
1203 To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
1205 The filename to provide to the input device is a source device or the
1208 To list the PulseAudio source devices and their properties you can invoke
1209 the command @command{pactl list sources}.
1211 More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
1216 Connect to a specific PulseAudio server, specified by an IP address.
1217 Default server is used when not provided.
1220 Specify the application name PulseAudio will use when showing active clients,
1221 by default it is the @code{LIBAVFORMAT_IDENT} string.
1224 Specify the stream name PulseAudio will use when showing active streams,
1225 by default it is "record".
1228 Specify the samplerate in Hz, by default 48kHz is used.
1231 Specify the channels in use, by default 2 (stereo) is set.
1234 Specify the number of bytes per frame, by default it is set to 1024.
1237 Specify the minimal buffering fragment in PulseAudio, it will affect the
1238 audio latency. By default it is unset.
1241 Set the initial PTS using the current time. Default is 1.
1245 @subsection Examples
1246 Record a stream from default device:
1248 ffmpeg -f pulse -i default /tmp/pulse.wav
1255 To enable this input device during configuration you need libsndio
1256 installed on your system.
1258 The filename to provide to the input device is the device node
1259 representing the sndio input device, and is usually set to
1262 For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
1265 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
1273 Set the sample rate in Hz. Default is 48000.
1276 Set the number of channels. Default is 2.
1280 @section video4linux2, v4l2
1282 Video4Linux2 input video device.
1284 "v4l2" can be used as alias for "video4linux2".
1286 If FFmpeg is built with v4l-utils support (by using the
1287 @code{--enable-libv4l2} configure option), it is possible to use it with the
1288 @code{-use_libv4l2} input device option.
1290 The name of the device to grab is a file device node, usually Linux
1291 systems tend to automatically create such nodes when the device
1292 (e.g. an USB webcam) is plugged into the system, and has a name of the
1293 kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
1296 Video4Linux2 devices usually support a limited set of
1297 @var{width}x@var{height} sizes and frame rates. You can check which are
1298 supported using @command{-list_formats all} for Video4Linux2 devices.
1299 Some devices, like TV cards, support one or more standards. It is possible
1300 to list all the supported standards using @command{-list_standards all}.
1302 The time base for the timestamps is 1 microsecond. Depending on the kernel
1303 version and configuration, the timestamps may be derived from the real time
1304 clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
1305 boot time, unaffected by NTP or manual changes to the clock). The
1306 @option{-timestamps abs} or @option{-ts abs} option can be used to force
1307 conversion into the real time clock.
1309 Some usage examples of the video4linux2 device with @command{ffmpeg}
1310 and @command{ffplay}:
1313 List supported formats for a video4linux2 device:
1315 ffplay -f video4linux2 -list_formats all /dev/video0
1319 Grab and show the input of a video4linux2 device:
1321 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
1325 Grab and record the input of a video4linux2 device, leave the
1326 frame rate and size as previously set:
1328 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
1332 For more information about Video4Linux, check @url{http://linuxtv.org/}.
1338 Set the standard. Must be the name of a supported standard. To get a
1339 list of the supported standards, use the @option{list_standards}
1343 Set the input channel number. Default to -1, which means using the
1344 previously selected channel.
1347 Set the video frame size. The argument must be a string in the form
1348 @var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
1351 Select the pixel format (only valid for raw video input).
1354 Set the preferred pixel format (for raw video) or a codec name.
1355 This option allows one to select the input format, when several are
1359 Set the preferred video frame rate.
1362 List available formats (supported pixel formats, codecs, and frame
1365 Available values are:
1368 Show all available (compressed and non-compressed) formats.
1371 Show only raw video (non-compressed) formats.
1374 Show only compressed formats.
1377 @item list_standards
1378 List supported standards and exit.
1380 Available values are:
1383 Show all supported standards.
1386 @item timestamps, ts
1387 Set type of timestamps for grabbed frames.
1389 Available values are:
1392 Use timestamps from the kernel.
1395 Use absolute timestamps (wall clock).
1398 Force conversion from monotonic to absolute timestamps.
1401 Default value is @code{default}.
1404 Use libv4l2 (v4l-utils) conversion functions. Default is 0.
1410 VfW (Video for Windows) capture input device.
1412 The filename passed as input is the capture driver number, ranging from
1413 0 to 9. You may use "list" as filename to print a list of drivers. Any
1414 other filename will be interpreted as device number 0.
1421 Set the video frame size.
1424 Set the grabbing frame rate. Default value is @code{ntsc},
1425 corresponding to a frame rate of @code{30000/1001}.
1431 X11 video input device.
1433 To enable this input device during configuration you need libxcb
1434 installed on your system. It will be automatically detected during
1437 This device allows one to capture a region of an X11 display.
1439 The filename passed as input has the syntax:
1441 [@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
1444 @var{hostname}:@var{display_number}.@var{screen_number} specifies the
1445 X11 display name of the screen to grab from. @var{hostname} can be
1446 omitted, and defaults to "localhost". The environment variable
1447 @env{DISPLAY} contains the default display name.
1449 @var{x_offset} and @var{y_offset} specify the offsets of the grabbed
1450 area with respect to the top-left border of the X11 screen. They
1453 Check the X11 documentation (e.g. @command{man X}) for more detailed
1456 Use the @command{xdpyinfo} program for getting basic information about
1457 the properties of your X11 display (e.g. grep for "name" or
1460 For example to grab from @file{:0.0} using @command{ffmpeg}:
1462 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
1465 Grab at position @code{10,20}:
1467 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1474 Specify whether to draw the mouse pointer. A value of @code{0} specifies
1475 not to draw the pointer. Default value is @code{1}.
1478 Make the grabbed area follow the mouse. The argument can be
1479 @code{centered} or a number of pixels @var{PIXELS}.
1481 When it is specified with "centered", the grabbing region follows the mouse
1482 pointer and keeps the pointer at the center of region; otherwise, the region
1483 follows only when the mouse pointer reaches within @var{PIXELS} (greater than
1484 zero) to the edge of region.
1488 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
1491 To follow only when the mouse pointer reaches within 100 pixels to edge:
1493 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
1497 Set the grabbing frame rate. Default value is @code{ntsc},
1498 corresponding to a frame rate of @code{30000/1001}.
1501 Show grabbed region on screen.
1503 If @var{show_region} is specified with @code{1}, then the grabbing
1504 region will be indicated on screen. With this option, it is easy to
1505 know what is being grabbed if only a portion of the screen is grabbed.
1508 Set the region border thickness if @option{-show_region 1} is used.
1509 Range is 1 to 128 and default is 3 (XCB-based x11grab only).
1513 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1516 With @var{follow_mouse}:
1518 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
1522 Set the video frame size. Default value is @code{vga}.
1526 Set the grabbing region coordinates. They are expressed as offset from
1527 the top left corner of the X11 window and correspond to the
1528 @var{x_offset} and @var{y_offset} parameters in the device name. The
1529 default value for both options is 0.
1532 @c man end INPUT DEVICES