1FFMPEG-DEVICES(1) FFMPEG-DEVICES(1)
2
6 ffmpeg-devices - FFmpeg devices
7
9 This document describes the input and output devices provided by the
10 libavdevice library.
11
13 The libavdevice library provides the same interface as libavformat.
14 Namely, an input device is considered like a demuxer, and an output
15 device like a muxer, and the interface and generic device options are
16 the same provided by libavformat (see the ffmpeg-formats manual).
17 In addition each input or output device may support so-called private
19 options, which are specific for that component.
20 Options may be set by specifying -option value in the FFmpeg tools, or
22 by setting the value explicitly in the device "AVFormatContext" options
23 or using the libavutil/opt.h API for programmatic use.
24
26 Input devices are configured elements in FFmpeg which enable accessing
27 the data coming from a multimedia device attached to your system.
28 When you configure your FFmpeg build, all the supported input devices
30 are enabled by default. You can list all available ones using the
31 configure option "--list-indevs".
32 You can disable all the input devices using the configure option
34 "--disable-indevs", and selectively enable an input device using the
35 option "--enable-indev=INDEV", or you can disable a particular input
36 device using the option "--disable-indev=INDEV".
37 The option "-devices" of the ff* tools will display the list of
39 supported input devices.
40 A description of the currently available input devices follows.
42 alsa
44 ALSA (Advanced Linux Sound Architecture) input device.
45 To enable this input device during configuration you need libasound
47 installed on your system.
48 This device allows capturing from an ALSA device. The name of the
50 device to capture has to be an ALSA card identifier.
51 An ALSA identifier has the syntax:
53 hw:<CARD>[,<DEV>[,<SUBDEV>]]
55 where the DEV and SUBDEV components are optional.
57 The three arguments (in order: CARD,DEV,SUBDEV) specify card number or
59 identifier, device number and subdevice number (-1 means any).
60 To see the list of cards currently recognized by your system check the
62 files /proc/asound/cards and /proc/asound/devices.
63 For example to capture with ffmpeg from an ALSA device with card id 0,
65 you may run the command:
66 ffmpeg -f alsa -i hw:0 alsaout.wav
68 For more information see:
70 <http://www.alsa-project.org/alsa-doc/alsa-lib/pcm.html>
71 Options
73 sample_rate
75 Set the sample rate in Hz. Default is 48000.
76 channels
78 Set the number of channels. Default is 2.
79 android_camera
81 Android camera input device.
82 This input devices uses the Android Camera2 NDK API which is available
84 on devices with API level 24+. The availability of android_camera is
85 autodetected during configuration.
86 This device allows capturing from all cameras on an Android device,
88 which are integrated into the Camera2 NDK API.
89 The available cameras are enumerated internally and can be selected
91 with the camera_index parameter. The input file string is discarded.
92 Generally the back facing camera has index 0 while the front facing
94 camera has index 1.
95 Options
97 video_size
99 Set the video size given as a string such as 640x480 or hd720.
100 Falls back to the first available configuration reported by Android
101 if requested video size is not available or by default.
102 framerate
104 Set the video framerate. Falls back to the first available
105 configuration reported by Android if requested framerate is not
106 available or by default (-1).
107 camera_index
109 Set the index of the camera to use. Default is 0.
110 input_queue_size
112 Set the maximum number of frames to buffer. Default is 5.
113 avfoundation
115 AVFoundation input device.
116 AVFoundation is the currently recommended framework by Apple for
118 streamgrabbing on OSX >= 10.7 as well as on iOS.
119 The input filename has to be given in the following syntax:
121 -i "[[VIDEO]:[AUDIO]]"
123 The first entry selects the video input while the latter selects the
125 audio input. The stream has to be specified by the device name or the
126 device index as shown by the device list. Alternatively, the video
127 and/or audio input device can be chosen by index using the
128 B<-video_device_index E<lt>INDEXE<gt>>
130 and/or
132 B<-audio_device_index E<lt>INDEXE<gt>>
134 , overriding any device name or index given in the input filename.
136 All available devices can be enumerated by using -list_devices true,
138 listing all device names and corresponding indices.
139 There are two device name aliases:
141 "default"
143 Select the AVFoundation default device of the corresponding type.
144 "none"
146 Do not record the corresponding media type. This is equivalent to
147 specifying an empty device name or index.
148 Options
150 AVFoundation supports the following options:
152 -list_devices <TRUE|FALSE>
154 If set to true, a list of all available input devices is given
155 showing all device names and indices.
156 -video_device_index <INDEX>
158 Specify the video device by its index. Overrides anything given in
159 the input filename.
160 -audio_device_index <INDEX>
162 Specify the audio device by its index. Overrides anything given in
163 the input filename.
164 -pixel_format <FORMAT>
166 Request the video device to use a specific pixel format. If the
167 specified format is not supported, a list of available formats is
168 given and the first one in this list is used instead. Available
169 pixel formats are: "monob, rgb555be, rgb555le, rgb565be, rgb565le,
170 rgb24, bgr24, 0rgb, bgr0, 0bgr, rgb0,
171 bgr48be, uyvy422, yuva444p, yuva444p16le, yuv444p, yuv422p16,
172 yuv422p10, yuv444p10,
173 yuv420p, nv12, yuyv422, gray"
174 -framerate
176 Set the grabbing frame rate. Default is "ntsc", corresponding to a
177 frame rate of "30000/1001".
178 -video_size
180 Set the video frame size.
181 -capture_cursor
183 Capture the mouse pointer. Default is 0.
184 -capture_mouse_clicks
186 Capture the screen mouse clicks. Default is 0.
187 -capture_raw_data
189 Capture the raw device data. Default is 0. Using this option may
190 result in receiving the underlying data delivered to the
191 AVFoundation framework. E.g. for muxed devices that sends raw DV
192 data to the framework (like tape-based camcorders), setting this
193 option to false results in extracted video frames captured in the
194 designated pixel format only. Setting this option to true results
195 in receiving the raw DV stream untouched.
196 Examples
198 • Print the list of AVFoundation supported devices and exit:
200 $ ffmpeg -f avfoundation -list_devices true -i ""
202 • Record video from video device 0 and audio from audio device 0 into
204 out.avi:
205 $ ffmpeg -f avfoundation -i "0:0" out.avi
207 • Record video from video device 2 and audio from audio device 1 into
209 out.avi:
210 $ ffmpeg -f avfoundation -video_device_index 2 -i ":1" out.avi
212 • Record video from the system default video device using the pixel
214 format bgr0 and do not record any audio into out.avi:
215 $ ffmpeg -f avfoundation -pixel_format bgr0 -i "default:none" out.avi
217 • Record raw DV data from a suitable input device and write the
219 output into out.dv:
220 $ ffmpeg -f avfoundation -capture_raw_data true -i "zr100:none" out.dv
222 bktr
224 BSD video input device.
225 Options
227 framerate
229 Set the frame rate.
230 video_size
232 Set the video frame size. Default is "vga".
233 standard
235 Available values are:
236 pal
238 ntsc
239 secam
240 paln
241 palm
242 ntscj
243 decklink
245 The decklink input device provides capture capabilities for Blackmagic
246 DeckLink devices.
247 To enable this input device, you need the Blackmagic DeckLink SDK and
249 you need to configure with the appropriate "--extra-cflags" and
250 "--extra-ldflags". On Windows, you need to run the IDL files through
251 widl.
252 DeckLink is very picky about the formats it supports. Pixel format of
254 the input can be set with raw_format. Framerate and video size must be
255 determined for your device with -list_formats 1. Audio sample rate is
256 always 48 kHz and the number of channels can be 2, 8 or 16. Note that
257 all audio channels are bundled in one single audio track.
258 Options
260 list_devices
262 If set to true, print a list of devices and exit. Defaults to
263 false. This option is deprecated, please use the "-sources" option
264 of ffmpeg to list the available input devices.
265 list_formats
267 If set to true, print a list of supported formats and exit.
268 Defaults to false.
269 format_code <FourCC>
271 This sets the input video format to the format given by the FourCC.
272 To see the supported values of your device(s) use list_formats.
273 Note that there is a FourCC 'pal ' that can also be used as pal (3
274 letters). Default behavior is autodetection of the input video
275 format, if the hardware supports it.
276 raw_format
278 Set the pixel format of the captured video. Available values are:
279 auto
281 This is the default which means 8-bit YUV 422 or 8-bit ARGB if
282 format autodetection is used, 8-bit YUV 422 otherwise.
283 uyvy422
285 8-bit YUV 422.
286 yuv422p10
288 10-bit YUV 422.
289 argb
291 8-bit RGB.
292 bgra
294 8-bit RGB.
295 rgb10
297 10-bit RGB.
298 teletext_lines
300 If set to nonzero, an additional teletext stream will be captured
301 from the vertical ancillary data. Both SD PAL (576i) and HD (1080i
302 or 1080p) sources are supported. In case of HD sources, OP47
303 packets are decoded.
304 This option is a bitmask of the SD PAL VBI lines captured,
306 specifically lines 6 to 22, and lines 318 to 335. Line 6 is the LSB
307 in the mask. Selected lines which do not contain teletext
308 information will be ignored. You can use the special all constant
309 to select all possible lines, or standard to skip lines 6, 318 and
310 319, which are not compatible with all receivers.
311 For SD sources, ffmpeg needs to be compiled with
313 "--enable-libzvbi". For HD sources, on older (pre-4K) DeckLink card
314 models you have to capture in 10 bit mode.
315 channels
317 Defines number of audio channels to capture. Must be 2, 8 or 16.
318 Defaults to 2.
319 duplex_mode
321 Sets the decklink device duplex/profile mode. Must be unset, half,
322 full, one_sub_device_full, one_sub_device_half,
323 two_sub_device_full, four_sub_device_half Defaults to unset.
324 Note: DeckLink SDK 11.0 have replaced the duplex property by a
326 profile property. For the DeckLink Duo 2 and DeckLink Quad 2, a
327 profile is shared between any 2 sub-devices that utilize the same
328 connectors. For the DeckLink 8K Pro, a profile is shared between
329 all 4 sub-devices. So DeckLink 8K Pro support four profiles.
330 Valid profile modes for DeckLink 8K Pro(with DeckLink SDK >= 11.0):
332 one_sub_device_full, one_sub_device_half, two_sub_device_full,
333 four_sub_device_half
334 Valid profile modes for DeckLink Quad 2 and DeckLink Duo 2: half,
336 full
337 timecode_format
339 Timecode type to include in the frame and video stream metadata.
340 Must be none, rp188vitc, rp188vitc2, rp188ltc, rp188hfr, rp188any,
341 vitc, vitc2, or serial. Defaults to none (not included).
342 In order to properly support 50/60 fps timecodes, the ordering of
344 the queried timecode types for rp188any is HFR, VITC1, VITC2 and
345 LTC for >30 fps content. Note that this is slightly different to
346 the ordering used by the DeckLink API, which is HFR, VITC1, LTC,
347 VITC2.
348 video_input
350 Sets the video input source. Must be unset, sdi, hdmi, optical_sdi,
351 component, composite or s_video. Defaults to unset.
352 audio_input
354 Sets the audio input source. Must be unset, embedded, aes_ebu,
355 analog, analog_xlr, analog_rca or microphone. Defaults to unset.
356 video_pts
358 Sets the video packet timestamp source. Must be video, audio,
359 reference, wallclock or abs_wallclock. Defaults to video.
360 audio_pts
362 Sets the audio packet timestamp source. Must be video, audio,
363 reference, wallclock or abs_wallclock. Defaults to audio.
364 draw_bars
366 If set to true, color bars are drawn in the event of a signal loss.
367 Defaults to true.
368 queue_size
370 Sets maximum input buffer size in bytes. If the buffering reaches
371 this value, incoming frames will be dropped. Defaults to
372 1073741824.
373 audio_depth
375 Sets the audio sample bit depth. Must be 16 or 32. Defaults to 16.
376 decklink_copyts
378 If set to true, timestamps are forwarded as they are without
379 removing the initial offset. Defaults to false.
380 timestamp_align
382 Capture start time alignment in seconds. If set to nonzero, input
383 frames are dropped till the system timestamp aligns with configured
384 value. Alignment difference of up to one frame duration is
385 tolerated. This is useful for maintaining input synchronization
386 across N different hardware devices deployed for 'N-way'
387 redundancy. The system time of different hardware devices should be
388 synchronized with protocols such as NTP or PTP, before using this
389 option. Note that this method is not foolproof. In some border
390 cases input synchronization may not happen due to thread scheduling
391 jitters in the OS. Either sync could go wrong by 1 frame or in a
392 rarer case timestamp_align seconds. Defaults to 0.
393 wait_for_tc (bool)
395 Drop frames till a frame with timecode is received. Sometimes
396 serial timecode isn't received with the first input frame. If that
397 happens, the stored stream timecode will be inaccurate. If this
398 option is set to true, input frames are dropped till a frame with
399 timecode is received. Option timecode_format must be specified.
400 Defaults to false.
401 enable_klv(bool)
403 If set to true, extracts KLV data from VANC and outputs KLV
404 packets. KLV VANC packets are joined based on MID and PSC fields
405 and aggregated into one KLV packet. Defaults to false.
406 Examples
408 • List input devices:
410 ffmpeg -sources decklink
412 • List supported formats:
414 ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
416 • Capture video clip at 1080i50:
418 ffmpeg -format_code Hi50 -f decklink -i 'Intensity Pro' -c:a copy -c:v copy output.avi
420 • Capture video clip at 1080i50 10 bit:
422 ffmpeg -raw_format yuv422p10 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
424 • Capture video clip at 1080i50 with 16 audio channels:
426 ffmpeg -channels 16 -format_code Hi50 -f decklink -i 'UltraStudio Mini Recorder' -c:a copy -c:v copy output.avi
428 dshow
430 Windows DirectShow input device.
431 DirectShow support is enabled when FFmpeg is built with the mingw-w64
433 project. Currently only audio and video devices are supported.
434 Multiple devices may be opened as separate inputs, but they may also be
436 opened on the same input, which should improve synchronism between
437 them.
438 The input name should be in the format:
440 <TYPE>=<NAME>[:<TYPE>=<NAME>]
442 where TYPE can be either audio or video, and NAME is the device's name
444 or alternative name..
445 Options
447 If no options are specified, the device's defaults are used. If the
449 device does not support the requested options, it will fail to open.
450 video_size
452 Set the video size in the captured video.
453 framerate
455 Set the frame rate in the captured video.
456 sample_rate
458 Set the sample rate (in Hz) of the captured audio.
459 sample_size
461 Set the sample size (in bits) of the captured audio.
462 channels
464 Set the number of channels in the captured audio.
465 list_devices
467 If set to true, print a list of devices and exit.
468 list_options
470 If set to true, print a list of selected device's options and exit.
471 video_device_number
473 Set video device number for devices with the same name (starts at
474 0, defaults to 0).
475 audio_device_number
477 Set audio device number for devices with the same name (starts at
478 0, defaults to 0).
479 pixel_format
481 Select pixel format to be used by DirectShow. This may only be set
482 when the video codec is not set or set to rawvideo.
483 audio_buffer_size
485 Set audio device buffer size in milliseconds (which can directly
486 impact latency, depending on the device). Defaults to using the
487 audio device's default buffer size (typically some multiple of
488 500ms). Setting this value too low can degrade performance. See
489 also
490 <http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx>
491 video_pin_name
493 Select video capture pin to use by name or alternative name.
494 audio_pin_name
496 Select audio capture pin to use by name or alternative name.
497 crossbar_video_input_pin_number
499 Select video input pin number for crossbar device. This will be
500 routed to the crossbar device's Video Decoder output pin. Note
501 that changing this value can affect future invocations (sets a new
502 default) until system reboot occurs.
503 crossbar_audio_input_pin_number
505 Select audio input pin number for crossbar device. This will be
506 routed to the crossbar device's Audio Decoder output pin. Note
507 that changing this value can affect future invocations (sets a new
508 default) until system reboot occurs.
509 show_video_device_dialog
511 If set to true, before capture starts, popup a display dialog to
512 the end user, allowing them to change video filter properties and
513 configurations manually. Note that for crossbar devices, adjusting
514 values in this dialog may be needed at times to toggle between PAL
515 (25 fps) and NTSC (29.97) input frame rates, sizes, interlacing,
516 etc. Changing these values can enable different scan rates/frame
517 rates and avoiding green bars at the bottom, flickering scan lines,
518 etc. Note that with some devices, changing these properties can
519 also affect future invocations (sets new defaults) until system
520 reboot occurs.
521 show_audio_device_dialog
523 If set to true, before capture starts, popup a display dialog to
524 the end user, allowing them to change audio filter properties and
525 configurations manually.
526 show_video_crossbar_connection_dialog
528 If set to true, before capture starts, popup a display dialog to
529 the end user, allowing them to manually modify crossbar pin
530 routings, when it opens a video device.
531 show_audio_crossbar_connection_dialog
533 If set to true, before capture starts, popup a display dialog to
534 the end user, allowing them to manually modify crossbar pin
535 routings, when it opens an audio device.
536 show_analog_tv_tuner_dialog
538 If set to true, before capture starts, popup a display dialog to
539 the end user, allowing them to manually modify TV channels and
540 frequencies.
541 show_analog_tv_tuner_audio_dialog
543 If set to true, before capture starts, popup a display dialog to
544 the end user, allowing them to manually modify TV audio (like mono
545 vs. stereo, Language A,B or C).
546 audio_device_load
548 Load an audio capture filter device from file instead of searching
549 it by name. It may load additional parameters too, if the filter
550 supports the serialization of its properties to. To use this an
551 audio capture source has to be specified, but it can be anything
552 even fake one.
553 audio_device_save
555 Save the currently used audio capture filter device and its
556 parameters (if the filter supports it) to a file. If a file with
557 the same name exists it will be overwritten.
558 video_device_load
560 Load a video capture filter device from file instead of searching
561 it by name. It may load additional parameters too, if the filter
562 supports the serialization of its properties to. To use this a
563 video capture source has to be specified, but it can be anything
564 even fake one.
565 video_device_save
567 Save the currently used video capture filter device and its
568 parameters (if the filter supports it) to a file. If a file with
569 the same name exists it will be overwritten.
570 use_video_device_timestamps
572 If set to false, the timestamp for video frames will be derived
573 from the wallclock instead of the timestamp provided by the capture
574 device. This allows working around devices that provide unreliable
575 timestamps.
576 Examples
578 • Print the list of DirectShow supported devices and exit:
580 $ ffmpeg -list_devices true -f dshow -i dummy
582 • Open video device Camera:
584 $ ffmpeg -f dshow -i video="Camera"
586 • Open second video device with name Camera:
588 $ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
590 • Open video device Camera and audio device Microphone:
592 $ ffmpeg -f dshow -i video="Camera":audio="Microphone"
594 • Print the list of supported options in selected device and exit:
596 $ ffmpeg -list_options true -f dshow -i video="Camera"
598 • Specify pin names to capture by name or alternative name, specify
600 alternative device name:
601 $ 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"
603 • Configure a crossbar device, specifying crossbar pins, allow user
605 to adjust video capture properties at startup:
606 $ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
608 -crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
609 fbdev
611 Linux framebuffer input device.
612 The Linux framebuffer is a graphic hardware-independent abstraction
614 layer to show graphics on a computer monitor, typically on the console.
615 It is accessed through a file device node, usually /dev/fb0.
616 For more detailed information read the file
618 Documentation/fb/framebuffer.txt included in the Linux source tree.
619 See also <http://linux-fbdev.sourceforge.net/>, and fbset(1).
621 To record from the framebuffer device /dev/fb0 with ffmpeg:
623 ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
625 You can take a single screenshot image with the command:
627 ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
629 Options
631 framerate
633 Set the frame rate. Default is 25.
634 gdigrab
636 Win32 GDI-based screen capture device.
637 This device allows you to capture a region of the display on Windows.
639 There are two options for the input filename:
641 desktop
643 or
645 title=<window_title>
647 The first option will capture the entire desktop, or a fixed region of
649 the desktop. The second option will instead capture the contents of a
650 single window, regardless of its position on the screen.
651 For example, to grab the entire desktop using ffmpeg:
653 ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
655 Grab a 640x480 region at position "10,20":
657 ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
659 Grab the contents of the window named "Calculator"
661 ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
663 Options
665 draw_mouse
667 Specify whether to draw the mouse pointer. Use the value 0 to not
668 draw the pointer. Default value is 1.
669 framerate
671 Set the grabbing frame rate. Default value is "ntsc", corresponding
672 to a frame rate of "30000/1001".
673 show_region
675 Show grabbed region on screen.
676 If show_region is specified with 1, then the grabbing region will
678 be indicated on screen. With this option, it is easy to know what
679 is being grabbed if only a portion of the screen is grabbed.
680 Note that show_region is incompatible with grabbing the contents of
682 a single window.
683 For example:
685 ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
687 video_size
689 Set the video frame size. The default is to capture the full screen
690 if desktop is selected, or the full window size if
691 title=window_title is selected.
692 offset_x
694 When capturing a region with video_size, set the distance from the
695 left edge of the screen or desktop.
696 Note that the offset calculation is from the top left corner of the
698 primary monitor on Windows. If you have a monitor positioned to the
699 left of your primary monitor, you will need to use a negative
700 offset_x value to move the region to that monitor.
701 offset_y
703 When capturing a region with video_size, set the distance from the
704 top edge of the screen or desktop.
705 Note that the offset calculation is from the top left corner of the
707 primary monitor on Windows. If you have a monitor positioned above
708 your primary monitor, you will need to use a negative offset_y
709 value to move the region to that monitor.
710 iec61883
712 FireWire DV/HDV input device using libiec61883.
713 To enable this input device, you need libiec61883, libraw1394 and
715 libavc1394 installed on your system. Use the configure option
716 "--enable-libiec61883" to compile with the device enabled.
717 The iec61883 capture device supports capturing from a video device
719 connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
720 FireWire stack (juju). This is the default DV/HDV input method in Linux
721 Kernel 2.6.37 and later, since the old FireWire stack was removed.
722 Specify the FireWire port to be used as input file, or "auto" to choose
724 the first port connected.
725 Options
727 dvtype
729 Override autodetection of DV/HDV. This should only be used if auto
730 detection does not work, or if usage of a different device type
731 should be prohibited. Treating a DV device as HDV (or vice versa)
732 will not work and result in undefined behavior. The values auto,
733 dv and hdv are supported.
734 dvbuffer
736 Set maximum size of buffer for incoming data, in frames. For DV,
737 this is an exact value. For HDV, it is not frame exact, since HDV
738 does not have a fixed frame size.
739 dvguid
741 Select the capture device by specifying its GUID. Capturing will
742 only be performed from the specified device and fails if no device
743 with the given GUID is found. This is useful to select the input if
744 multiple devices are connected at the same time. Look at
745 /sys/bus/firewire/devices to find out the GUIDs.
746 Examples
748 • Grab and show the input of a FireWire DV/HDV device.
750 ffplay -f iec61883 -i auto
752 • Grab and record the input of a FireWire DV/HDV device, using a
754 packet buffer of 100000 packets if the source is HDV.
755 ffmpeg -f iec61883 -i auto -dvbuffer 100000 out.mpg
757 jack
759 JACK input device.
760 To enable this input device during configuration you need libjack
762 installed on your system.
763 A JACK input device creates one or more JACK writable clients, one for
765 each audio channel, with name client_name:input_N, where client_name is
766 the name provided by the application, and N is a number which
767 identifies the channel. Each writable client will send the acquired
768 data to the FFmpeg input device.
769 Once you have created one or more JACK readable clients, you need to
771 connect them to one or more JACK writable clients.
772 To connect or disconnect JACK clients you can use the jack_connect and
774 jack_disconnect programs, or do it through a graphical interface, for
775 example with qjackctl.
776 To list the JACK clients and their properties you can invoke the
778 command jack_lsp.
779 Follows an example which shows how to capture a JACK readable client
781 with ffmpeg.
782 # Create a JACK writable client with name "ffmpeg".
784 $ ffmpeg -f jack -i ffmpeg -y out.wav
785 # Start the sample jack_metro readable client.
787 $ jack_metro -b 120 -d 0.2 -f 4000
788 # List the current JACK clients.
790 $ jack_lsp -c
791 system:capture_1
792 system:capture_2
793 system:playback_1
794 system:playback_2
795 ffmpeg:input_1
796 metro:120_bpm
797 # Connect metro to the ffmpeg writable client.
799 $ jack_connect metro:120_bpm ffmpeg:input_1
800 For more information read: <http://jackaudio.org/>
802 Options
804 channels
806 Set the number of channels. Default is 2.
807 kmsgrab
809 KMS video input device.
810 Captures the KMS scanout framebuffer associated with a specified CRTC
812 or plane as a DRM object that can be passed to other hardware
813 functions.
814 Requires either DRM master or CAP_SYS_ADMIN to run.
816 If you don't understand what all of that means, you probably don't want
818 this. Look at x11grab instead.
819 Options
821 device
823 DRM device to capture on. Defaults to /dev/dri/card0.
824 format
826 Pixel format of the framebuffer. This can be autodetected if you
827 are running Linux 5.7 or later, but needs to be provided for
828 earlier versions. Defaults to bgr0, which is the most common
829 format used by the Linux console and Xorg X server.
830 format_modifier
832 Format modifier to signal on output frames. This is necessary to
833 import correctly into some APIs. It can be autodetected if you are
834 running Linux 5.7 or later, but will need to be provided explicitly
835 when needed in earlier versions. See the libdrm documentation for
836 possible values.
837 crtc_id
839 KMS CRTC ID to define the capture source. The first active plane
840 on the given CRTC will be used.
841 plane_id
843 KMS plane ID to define the capture source. Defaults to the first
844 active plane found if neither crtc_id nor plane_id are specified.
845 framerate
847 Framerate to capture at. This is not synchronised to any page
848 flipping or framebuffer changes - it just defines the interval at
849 which the framebuffer is sampled. Sampling faster than the
850 framebuffer update rate will generate independent frames with the
851 same content. Defaults to 30.
852 Examples
854 • Capture from the first active plane, download the result to normal
856 frames and encode. This will only work if the framebuffer is both
857 linear and mappable - if not, the result may be scrambled or fail
858 to download.
859 ffmpeg -f kmsgrab -i - -vf 'hwdownload,format=bgr0' output.mp4
861 • Capture from CRTC ID 42 at 60fps, map the result to VAAPI, convert
863 to NV12 and encode as H.264.
864 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
866 • To capture only part of a plane the output can be cropped - this
868 can be used to capture a single window, as long as it has a known
869 absolute position and size. For example, to capture and encode the
870 middle quarter of a 1920x1080 plane:
871 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
873 lavfi
875 Libavfilter input virtual device.
876 This input device reads data from the open output pads of a libavfilter
878 filtergraph.
879 For each filtergraph open output, the input device will create a
881 corresponding stream which is mapped to the generated output. Currently
882 only video data is supported. The filtergraph is specified through the
883 option graph.
884 Options
886 graph
888 Specify the filtergraph to use as input. Each video open output
889 must be labelled by a unique string of the form "outN", where N is
890 a number starting from 0 corresponding to the mapped input stream
891 generated by the device. The first unlabelled output is
892 automatically assigned to the "out0" label, but all the others need
893 to be specified explicitly.
894 The suffix "+subcc" can be appended to the output label to create
896 an extra stream with the closed captions packets attached to that
897 output (experimental; only for EIA-608 / CEA-708 for now). The
898 subcc streams are created after all the normal streams, in the
899 order of the corresponding stream. For example, if there is
900 "out19+subcc", "out7+subcc" and up to "out42", the stream #43 is
901 subcc for stream #7 and stream #44 is subcc for stream #19.
902 If not specified defaults to the filename specified for the input
904 device.
905 graph_file
907 Set the filename of the filtergraph to be read and sent to the
908 other filters. Syntax of the filtergraph is the same as the one
909 specified by the option graph.
910 dumpgraph
912 Dump graph to stderr.
913 Examples
915 • Create a color video stream and play it back with ffplay:
917 ffplay -f lavfi -graph "color=c=pink [out0]" dummy
919 • As the previous example, but use filename for specifying the graph
921 description, and omit the "out0" label:
922 ffplay -f lavfi color=c=pink
924 • Create three different video test filtered sources and play them:
926 ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
928 • Read an audio stream from a file using the amovie source and play
930 it back with ffplay:
931 ffplay -f lavfi "amovie=test.wav"
933 • Read an audio stream and a video stream and play it back with
935 ffplay:
936 ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
938 • Dump decoded frames to images and closed captions to a file
940 (experimental):
941 ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
943 libcdio
945 Audio-CD input device based on libcdio.
946 To enable this input device during configuration you need libcdio
948 installed on your system. It requires the configure option
949 "--enable-libcdio".
950 This device allows playing and grabbing from an Audio-CD.
952 For example to copy with ffmpeg the entire Audio-CD in /dev/sr0, you
954 may run the command:
955 ffmpeg -f libcdio -i /dev/sr0 cd.wav
957 Options
959 speed
961 Set drive reading speed. Default value is 0.
962 The speed is specified CD-ROM speed units. The speed is set through
964 the libcdio "cdio_cddap_speed_set" function. On many CD-ROM drives,
965 specifying a value too large will result in using the fastest
966 speed.
967 paranoia_mode
969 Set paranoia recovery mode flags. It accepts one of the following
970 values:
971 disable
973 verify
974 overlap
975 neverskip
976 full
977 Default value is disable.
979 For more information about the available recovery modes, consult
981 the paranoia project documentation.
982 libdc1394
984 IIDC1394 input device, based on libdc1394 and libraw1394.
985 Requires the configure option "--enable-libdc1394".
987 Options
989 framerate
991 Set the frame rate. Default is "ntsc", corresponding to a frame
992 rate of "30000/1001".
993 pixel_format
995 Select the pixel format. Default is "uyvy422".
996 video_size
998 Set the video size given as a string such as "640x480" or "hd720".
999 Default is "qvga".
1000 openal
1002 The OpenAL input device provides audio capture on all systems with a
1003 working OpenAL 1.1 implementation.
1004 To enable this input device during configuration, you need OpenAL
1006 headers and libraries installed on your system, and need to configure
1007 FFmpeg with "--enable-openal".
1008 OpenAL headers and libraries should be provided as part of your OpenAL
1010 implementation, or as an additional download (an SDK). Depending on
1011 your installation you may need to specify additional flags via the
1012 "--extra-cflags" and "--extra-ldflags" for allowing the build system to
1013 locate the OpenAL headers and libraries.
1014 An incomplete list of OpenAL implementations follows:
1016 Creative
1018 The official Windows implementation, providing hardware
1019 acceleration with supported devices and software fallback. See
1020 <http://openal.org/>.
1021 OpenAL Soft
1023 Portable, open source (LGPL) software implementation. Includes
1024 backends for the most common sound APIs on the Windows, Linux,
1025 Solaris, and BSD operating systems. See
1026 <http://kcat.strangesoft.net/openal.html>.
1027 Apple
1029 OpenAL is part of Core Audio, the official Mac OS X Audio
1030 interface. See
1031 <http://developer.apple.com/technologies/mac/audio-and-video.html>
1032 This device allows one to capture from an audio input device handled
1034 through OpenAL.
1035 You need to specify the name of the device to capture in the provided
1037 filename. If the empty string is provided, the device will
1038 automatically select the default device. You can get the list of the
1039 supported devices by using the option list_devices.
1040 Options
1042 channels
1044 Set the number of channels in the captured audio. Only the values 1
1045 (monaural) and 2 (stereo) are currently supported. Defaults to 2.
1046 sample_size
1048 Set the sample size (in bits) of the captured audio. Only the
1049 values 8 and 16 are currently supported. Defaults to 16.
1050 sample_rate
1052 Set the sample rate (in Hz) of the captured audio. Defaults to
1053 44.1k.
1054 list_devices
1056 If set to true, print a list of devices and exit. Defaults to
1057 false.
1058 Examples
1060 Print the list of OpenAL supported devices and exit:
1062 $ ffmpeg -list_devices true -f openal -i dummy out.ogg
1064 Capture from the OpenAL device DR-BT101 via PulseAudio:
1066 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
1068 Capture from the default device (note the empty string '' as filename):
1070 $ ffmpeg -f openal -i '' out.ogg
1072 Capture from two devices simultaneously, writing to two different
1074 files, within the same ffmpeg command:
1075 $ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
1077 Note: not all OpenAL implementations support multiple simultaneous
1079 capture - try the latest OpenAL Soft if the above does not work.
1080 oss
1082 Open Sound System input device.
1083 The filename to provide to the input device is the device node
1085 representing the OSS input device, and is usually set to /dev/dsp.
1086 For example to grab from /dev/dsp using ffmpeg use the command:
1088 ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
1090 For more information about OSS see:
1092 <http://manuals.opensound.com/usersguide/dsp.html>
1093 Options
1095 sample_rate
1097 Set the sample rate in Hz. Default is 48000.
1098 channels
1100 Set the number of channels. Default is 2.
1101 pulse
1103 PulseAudio input device.
1104 To enable this output device you need to configure FFmpeg with
1106 "--enable-libpulse".
1107 The filename to provide to the input device is a source device or the
1109 string "default"
1110 To list the PulseAudio source devices and their properties you can
1112 invoke the command pactl list sources.
1113 More information about PulseAudio can be found on
1115 <http://www.pulseaudio.org>.
1116 Options
1118 server
1120 Connect to a specific PulseAudio server, specified by an IP
1121 address. Default server is used when not provided.
1122 name
1124 Specify the application name PulseAudio will use when showing
1125 active clients, by default it is the "LIBAVFORMAT_IDENT" string.
1126 stream_name
1128 Specify the stream name PulseAudio will use when showing active
1129 streams, by default it is "record".
1130 sample_rate
1132 Specify the samplerate in Hz, by default 48kHz is used.
1133 channels
1135 Specify the channels in use, by default 2 (stereo) is set.
1136 frame_size
1138 Specify the number of bytes per frame, by default it is set to
1139 1024.
1140 fragment_size
1142 Specify the minimal buffering fragment in PulseAudio, it will
1143 affect the audio latency. By default it is unset.
1144 wallclock
1146 Set the initial PTS using the current time. Default is 1.
1147 Examples
1149 Record a stream from default device:
1151 ffmpeg -f pulse -i default /tmp/pulse.wav
1153 sndio
1155 sndio input device.
1156 To enable this input device during configuration you need libsndio
1158 installed on your system.
1159 The filename to provide to the input device is the device node
1161 representing the sndio input device, and is usually set to /dev/audio0.
1162 For example to grab from /dev/audio0 using ffmpeg use the command:
1164 ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
1166 Options
1168 sample_rate
1170 Set the sample rate in Hz. Default is 48000.
1171 channels
1173 Set the number of channels. Default is 2.
1174 video4linux2, v4l2
1176 Video4Linux2 input video device.
1177 "v4l2" can be used as alias for "video4linux2".
1179 If FFmpeg is built with v4l-utils support (by using the
1181 "--enable-libv4l2" configure option), it is possible to use it with the
1182 "-use_libv4l2" input device option.
1183 The name of the device to grab is a file device node, usually Linux
1185 systems tend to automatically create such nodes when the device (e.g.
1186 an USB webcam) is plugged into the system, and has a name of the kind
1187 /dev/videoN, where N is a number associated to the device.
1188 Video4Linux2 devices usually support a limited set of widthxheight
1190 sizes and frame rates. You can check which are supported using
1191 -list_formats all for Video4Linux2 devices. Some devices, like TV
1192 cards, support one or more standards. It is possible to list all the
1193 supported standards using -list_standards all.
1194 The time base for the timestamps is 1 microsecond. Depending on the
1196 kernel version and configuration, the timestamps may be derived from
1197 the real time clock (origin at the Unix Epoch) or the monotonic clock
1198 (origin usually at boot time, unaffected by NTP or manual changes to
1199 the clock). The -timestamps abs or -ts abs option can be used to force
1200 conversion into the real time clock.
1201 Some usage examples of the video4linux2 device with ffmpeg and ffplay:
1203 • List supported formats for a video4linux2 device:
1205 ffplay -f video4linux2 -list_formats all /dev/video0
1207 • Grab and show the input of a video4linux2 device:
1209 ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
1211 • Grab and record the input of a video4linux2 device, leave the frame
1213 rate and size as previously set:
1214 ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
1216 For more information about Video4Linux, check <http://linuxtv.org/>.
1218 Options
1220 standard
1222 Set the standard. Must be the name of a supported standard. To get
1223 a list of the supported standards, use the list_standards option.
1224 channel
1226 Set the input channel number. Default to -1, which means using the
1227 previously selected channel.
1228 video_size
1230 Set the video frame size. The argument must be a string in the form
1231 WIDTHxHEIGHT or a valid size abbreviation.
1232 pixel_format
1234 Select the pixel format (only valid for raw video input).
1235 input_format
1237 Set the preferred pixel format (for raw video) or a codec name.
1238 This option allows one to select the input format, when several are
1239 available.
1240 framerate
1242 Set the preferred video frame rate.
1243 list_formats
1245 List available formats (supported pixel formats, codecs, and frame
1246 sizes) and exit.
1247 Available values are:
1249 all Show all available (compressed and non-compressed) formats.
1251 raw Show only raw video (non-compressed) formats.
1253 compressed
1255 Show only compressed formats.
1256 list_standards
1258 List supported standards and exit.
1259 Available values are:
1261 all Show all supported standards.
1263 timestamps, ts
1265 Set type of timestamps for grabbed frames.
1266 Available values are:
1268 default
1270 Use timestamps from the kernel.
1271 abs Use absolute timestamps (wall clock).
1273 mono2abs
1275 Force conversion from monotonic to absolute timestamps.
1276 Default value is "default".
1278 use_libv4l2
1280 Use libv4l2 (v4l-utils) conversion functions. Default is 0.
1281 vfwcap
1283 VfW (Video for Windows) capture input device.
1284 The filename passed as input is the capture driver number, ranging from
1286 0 to 9. You may use "list" as filename to print a list of drivers. Any
1287 other filename will be interpreted as device number 0.
1288 Options
1290 video_size
1292 Set the video frame size.
1293 framerate
1295 Set the grabbing frame rate. Default value is "ntsc", corresponding
1296 to a frame rate of "30000/1001".
1297 x11grab
1299 X11 video input device.
1300 To enable this input device during configuration you need libxcb
1302 installed on your system. It will be automatically detected during
1303 configuration.
1304 This device allows one to capture a region of an X11 display.
1306 The filename passed as input has the syntax:
1308 [<hostname>]:<display_number>.<screen_number>[+<x_offset>,<y_offset>]
1310 hostname:display_number.screen_number specifies the X11 display name of
1312 the screen to grab from. hostname can be omitted, and defaults to
1313 "localhost". The environment variable DISPLAY contains the default
1314 display name.
1315 x_offset and y_offset specify the offsets of the grabbed area with
1317 respect to the top-left border of the X11 screen. They default to 0.
1318 Check the X11 documentation (e.g. man X) for more detailed information.
1320 Use the xdpyinfo program for getting basic information about the
1322 properties of your X11 display (e.g. grep for "name" or "dimensions").
1323 For example to grab from :0.0 using ffmpeg:
1325 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
1327 Grab at position "10,20":
1329 ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1331 Options
1333 select_region
1335 Specify whether to select the grabbing area graphically using the
1336 pointer. A value of 1 prompts the user to select the grabbing area
1337 graphically by clicking and dragging. A single click with no
1338 dragging will select the whole screen. A region with zero width or
1339 height will also select the whole screen. This option overwrites
1340 the video_size, grab_x, and grab_y options. Default value is 0.
1341 draw_mouse
1343 Specify whether to draw the mouse pointer. A value of 0 specifies
1344 not to draw the pointer. Default value is 1.
1345 follow_mouse
1347 Make the grabbed area follow the mouse. The argument can be
1348 "centered" or a number of pixels PIXELS.
1349 When it is specified with "centered", the grabbing region follows
1351 the mouse pointer and keeps the pointer at the center of region;
1352 otherwise, the region follows only when the mouse pointer reaches
1353 within PIXELS (greater than zero) to the edge of region.
1354 For example:
1356 ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
1358 To follow only when the mouse pointer reaches within 100 pixels to
1360 edge:
1361 ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
1363 framerate
1365 Set the grabbing frame rate. Default value is "ntsc", corresponding
1366 to a frame rate of "30000/1001".
1367 show_region
1369 Show grabbed region on screen.
1370 If show_region is specified with 1, then the grabbing region will
1372 be indicated on screen. With this option, it is easy to know what
1373 is being grabbed if only a portion of the screen is grabbed.
1374 region_border
1376 Set the region border thickness if -show_region 1 is used. Range
1377 is 1 to 128 and default is 3 (XCB-based x11grab only).
1378 For example:
1380 ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
1382 With follow_mouse:
1384 ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
1386 window_id
1388 Grab this window, instead of the whole screen. Default value is 0,
1389 which maps to the whole screen (root window).
1390 The id of a window can be found using the xwininfo program,
1392 possibly with options -tree and -root.
1393 If the window is later enlarged, the new area is not recorded.
1395 Video ends when the window is closed, unmapped (i.e., iconified) or
1396 shrunk beyond the video size (which defaults to the initial window
1397 size).
1398 This option disables options follow_mouse and select_region.
1400 video_size
1402 Set the video frame size. Default is the full desktop or window.
1403 grab_x
1405 grab_y
1406 Set the grabbing region coordinates. They are expressed as offset
1407 from the top left corner of the X11 window and correspond to the
1408 x_offset and y_offset parameters in the device name. The default
1409 value for both options is 0.
1410
1412 Output devices are configured elements in FFmpeg that can write
1413 multimedia data to an output device attached to your system.
1414 When you configure your FFmpeg build, all the supported output devices
1416 are enabled by default. You can list all available ones using the
1417 configure option "--list-outdevs".
1418 You can disable all the output devices using the configure option
1420 "--disable-outdevs", and selectively enable an output device using the
1421 option "--enable-outdev=OUTDEV", or you can disable a particular input
1422 device using the option "--disable-outdev=OUTDEV".
1423 The option "-devices" of the ff* tools will display the list of enabled
1425 output devices.
1426 A description of the currently available output devices follows.
1428 alsa
1430 ALSA (Advanced Linux Sound Architecture) output device.
1431 Examples
1433 • Play a file on default ALSA device:
1435 ffmpeg -i INPUT -f alsa default
1437 • Play a file on soundcard 1, audio device 7:
1439 ffmpeg -i INPUT -f alsa hw:1,7
1441 AudioToolbox
1443 AudioToolbox output device.
1444 Allows native output to CoreAudio devices on OSX.
1446 The output filename can be empty (or "-") to refer to the default
1448 system output device or a number that refers to the device index as
1449 shown using: "-list_devices true".
1450 Alternatively, the audio input device can be chosen by index using the
1452 B<-audio_device_index E<lt>INDEXE<gt>>
1454 , overriding any device name or index given in the input filename.
1456 All available devices can be enumerated by using -list_devices true,
1458 listing all device names, UIDs and corresponding indices.
1459 Options
1461 AudioToolbox supports the following options:
1463 -audio_device_index <INDEX>
1465 Specify the audio device by its index. Overrides anything given in
1466 the output filename.
1467 Examples
1469 • Print the list of supported devices and output a sine wave to the
1471 default device:
1472 $ ffmpeg -f lavfi -i sine=r=44100 -f audiotoolbox -list_devices true -
1474 • Output a sine wave to the device with the index 2, overriding any
1476 output filename:
1477 $ ffmpeg -f lavfi -i sine=r=44100 -f audiotoolbox -audio_device_index 2 -
1479 caca
1481 CACA output device.
1482 This output device allows one to show a video stream in CACA window.
1484 Only one CACA window is allowed per application, so you can have only
1485 one instance of this output device in an application.
1486 To enable this output device you need to configure FFmpeg with
1488 "--enable-libcaca". libcaca is a graphics library that outputs text
1489 instead of pixels.
1490 For more information about libcaca, check:
1492 <http://caca.zoy.org/wiki/libcaca>
1493 Options
1495 window_title
1497 Set the CACA window title, if not specified default to the filename
1498 specified for the output device.
1499 window_size
1501 Set the CACA window size, can be a string of the form widthxheight
1502 or a video size abbreviation. If not specified it defaults to the
1503 size of the input video.
1504 driver
1506 Set display driver.
1507 algorithm
1509 Set dithering algorithm. Dithering is necessary because the picture
1510 being rendered has usually far more colours than the available
1511 palette. The accepted values are listed with "-list_dither
1512 algorithms".
1513 antialias
1515 Set antialias method. Antialiasing smoothens the rendered image and
1516 avoids the commonly seen staircase effect. The accepted values are
1517 listed with "-list_dither antialiases".
1518 charset
1520 Set which characters are going to be used when rendering text. The
1521 accepted values are listed with "-list_dither charsets".
1522 color
1524 Set color to be used when rendering text. The accepted values are
1525 listed with "-list_dither colors".
1526 list_drivers
1528 If set to true, print a list of available drivers and exit.
1529 list_dither
1531 List available dither options related to the argument. The
1532 argument must be one of "algorithms", "antialiases", "charsets",
1533 "colors".
1534 Examples
1536 • The following command shows the ffmpeg output is an CACA window,
1538 forcing its size to 80x25:
1539 ffmpeg -i INPUT -c:v rawvideo -pix_fmt rgb24 -window_size 80x25 -f caca -
1541 • Show the list of available drivers and exit:
1543 ffmpeg -i INPUT -pix_fmt rgb24 -f caca -list_drivers true -
1545 • Show the list of available dither colors and exit:
1547 ffmpeg -i INPUT -pix_fmt rgb24 -f caca -list_dither colors -
1549 decklink
1551 The decklink output device provides playback capabilities for
1552 Blackmagic DeckLink devices.
1553 To enable this output device, you need the Blackmagic DeckLink SDK and
1555 you need to configure with the appropriate "--extra-cflags" and
1556 "--extra-ldflags". On Windows, you need to run the IDL files through
1557 widl.
1558 DeckLink is very picky about the formats it supports. Pixel format is
1560 always uyvy422, framerate, field order and video size must be
1561 determined for your device with -list_formats 1. Audio sample rate is
1562 always 48 kHz.
1563 Options
1565 list_devices
1567 If set to true, print a list of devices and exit. Defaults to
1568 false. This option is deprecated, please use the "-sinks" option of
1569 ffmpeg to list the available output devices.
1570 list_formats
1572 If set to true, print a list of supported formats and exit.
1573 Defaults to false.
1574 preroll
1576 Amount of time to preroll video in seconds. Defaults to 0.5.
1577 duplex_mode
1579 Sets the decklink device duplex/profile mode. Must be unset, half,
1580 full, one_sub_device_full, one_sub_device_half,
1581 two_sub_device_full, four_sub_device_half Defaults to unset.
1582 Note: DeckLink SDK 11.0 have replaced the duplex property by a
1584 profile property. For the DeckLink Duo 2 and DeckLink Quad 2, a
1585 profile is shared between any 2 sub-devices that utilize the same
1586 connectors. For the DeckLink 8K Pro, a profile is shared between
1587 all 4 sub-devices. So DeckLink 8K Pro support four profiles.
1588 Valid profile modes for DeckLink 8K Pro(with DeckLink SDK >= 11.0):
1590 one_sub_device_full, one_sub_device_half, two_sub_device_full,
1591 four_sub_device_half
1592 Valid profile modes for DeckLink Quad 2 and DeckLink Duo 2: half,
1594 full
1595 timing_offset
1597 Sets the genlock timing pixel offset on the used output. Defaults
1598 to unset.
1599 link
1601 Sets the SDI video link configuration on the used output. Must be
1602 unset, single link SDI, dual link SDI or quad link SDI. Defaults
1603 to unset.
1604 sqd Enable Square Division Quad Split mode for Quad-link SDI output.
1606 Must be unset, true or false. Defaults to unset.
1607 level_a
1609 Enable SMPTE Level A mode on the used output. Must be unset, true
1610 or false. Defaults to unset.
1611 Examples
1613 • List output devices:
1615 ffmpeg -sinks decklink
1617 • List supported formats:
1619 ffmpeg -i test.avi -f decklink -list_formats 1 'DeckLink Mini Monitor'
1621 • Play video clip:
1623 ffmpeg -i test.avi -f decklink -pix_fmt uyvy422 'DeckLink Mini Monitor'
1625 • Play video clip with non-standard framerate or video size:
1627 ffmpeg -i test.avi -f decklink -pix_fmt uyvy422 -s 720x486 -r 24000/1001 'DeckLink Mini Monitor'
1629 fbdev
1631 Linux framebuffer output device.
1632 The Linux framebuffer is a graphic hardware-independent abstraction
1634 layer to show graphics on a computer monitor, typically on the console.
1635 It is accessed through a file device node, usually /dev/fb0.
1636 For more detailed information read the file
1638 Documentation/fb/framebuffer.txt included in the Linux source tree.
1639 Options
1641 xoffset
1643 yoffset
1644 Set x/y coordinate of top left corner. Default is 0.
1645 Examples
1647 Play a file on framebuffer device /dev/fb0. Required pixel format
1649 depends on current framebuffer settings.
1650 ffmpeg -re -i INPUT -c:v rawvideo -pix_fmt bgra -f fbdev /dev/fb0
1652 See also <http://linux-fbdev.sourceforge.net/>, and fbset(1).
1654 opengl
1656 OpenGL output device.
1657 To enable this output device you need to configure FFmpeg with
1659 "--enable-opengl".
1660 This output device allows one to render to OpenGL context. Context may
1662 be provided by application or default SDL window is created.
1663 When device renders to external context, application must implement
1665 handlers for following messages: "AV_DEV_TO_APP_CREATE_WINDOW_BUFFER" -
1666 create OpenGL context on current thread.
1667 "AV_DEV_TO_APP_PREPARE_WINDOW_BUFFER" - make OpenGL context current.
1668 "AV_DEV_TO_APP_DISPLAY_WINDOW_BUFFER" - swap buffers.
1669 "AV_DEV_TO_APP_DESTROY_WINDOW_BUFFER" - destroy OpenGL context.
1670 Application is also required to inform a device about current
1671 resolution by sending "AV_APP_TO_DEV_WINDOW_SIZE" message.
1672 Options
1674 background
1676 Set background color. Black is a default.
1677 no_window
1679 Disables default SDL window when set to non-zero value.
1680 Application must provide OpenGL context and both "window_size_cb"
1681 and "window_swap_buffers_cb" callbacks when set.
1682 window_title
1684 Set the SDL window title, if not specified default to the filename
1685 specified for the output device. Ignored when no_window is set.
1686 window_size
1688 Set preferred window size, can be a string of the form widthxheight
1689 or a video size abbreviation. If not specified it defaults to the
1690 size of the input video, downscaled according to the aspect ratio.
1691 Mostly usable when no_window is not set.
1692 Examples
1694 Play a file on SDL window using OpenGL rendering:
1696 ffmpeg -i INPUT -f opengl "window title"
1698 oss
1700 OSS (Open Sound System) output device.
1701 pulse
1703 PulseAudio output device.
1704 To enable this output device you need to configure FFmpeg with
1706 "--enable-libpulse".
1707 More information about PulseAudio can be found on
1709 <http://www.pulseaudio.org>
1710 Options
1712 server
1714 Connect to a specific PulseAudio server, specified by an IP
1715 address. Default server is used when not provided.
1716 name
1718 Specify the application name PulseAudio will use when showing
1719 active clients, by default it is the "LIBAVFORMAT_IDENT" string.
1720 stream_name
1722 Specify the stream name PulseAudio will use when showing active
1723 streams, by default it is set to the specified output name.
1724 device
1726 Specify the device to use. Default device is used when not
1727 provided. List of output devices can be obtained with command
1728 pactl list sinks.
1729 buffer_size
1731 buffer_duration
1732 Control the size and duration of the PulseAudio buffer. A small
1733 buffer gives more control, but requires more frequent updates.
1734 buffer_size specifies size in bytes while buffer_duration specifies
1736 duration in milliseconds.
1737 When both options are provided then the highest value is used
1739 (duration is recalculated to bytes using stream parameters). If
1740 they are set to 0 (which is default), the device will use the
1741 default PulseAudio duration value. By default PulseAudio set buffer
1742 duration to around 2 seconds.
1743 prebuf
1745 Specify pre-buffering size in bytes. The server does not start with
1746 playback before at least prebuf bytes are available in the buffer.
1747 By default this option is initialized to the same value as
1748 buffer_size or buffer_duration (whichever is bigger).
1749 minreq
1751 Specify minimum request size in bytes. The server does not request
1752 less than minreq bytes from the client, instead waits until the
1753 buffer is free enough to request more bytes at once. It is
1754 recommended to not set this option, which will initialize this to a
1755 value that is deemed sensible by the server.
1756 Examples
1758 Play a file on default device on default server:
1760 ffmpeg -i INPUT -f pulse "stream name"
1762 sdl
1764 SDL (Simple DirectMedia Layer) output device.
1765 "sdl2" can be used as alias for "sdl".
1767 This output device allows one to show a video stream in an SDL window.
1769 Only one SDL window is allowed per application, so you can have only
1770 one instance of this output device in an application.
1771 To enable this output device you need libsdl installed on your system
1773 when configuring your build.
1774 For more information about SDL, check: <http://www.libsdl.org/>
1776 Options
1778 window_title
1780 Set the SDL window title, if not specified default to the filename
1781 specified for the output device.
1782 icon_title
1784 Set the name of the iconified SDL window, if not specified it is
1785 set to the same value of window_title.
1786 window_size
1788 Set the SDL window size, can be a string of the form widthxheight
1789 or a video size abbreviation. If not specified it defaults to the
1790 size of the input video, downscaled according to the aspect ratio.
1791 window_x
1793 window_y
1794 Set the position of the window on the screen.
1795 window_fullscreen
1797 Set fullscreen mode when non-zero value is provided. Default value
1798 is zero.
1799 window_enable_quit
1801 Enable quit action (using window button or keyboard key) when non-
1802 zero value is provided. Default value is 1 (enable quit action)
1803 Interactive commands
1805 The window created by the device can be controlled through the
1807 following interactive commands.
1808 q, ESC
1810 Quit the device immediately.
1811 Examples
1813 The following command shows the ffmpeg output is an SDL window, forcing
1815 its size to the qcif format:
1816 ffmpeg -i INPUT -c:v rawvideo -pix_fmt yuv420p -window_size qcif -f sdl "SDL output"
1818 sndio
1820 sndio audio output device.
1821 v4l2
1823 Video4Linux2 output device.
1824 xv
1826 XV (XVideo) output device.
1827 This output device allows one to show a video stream in a X Window
1829 System window.
1830 Options
1832 display_name
1834 Specify the hardware display name, which determines the display and
1835 communications domain to be used.
1836 The display name or DISPLAY environment variable can be a string in
1838 the format hostname[:number[.screen_number]].
1839 hostname specifies the name of the host machine on which the
1841 display is physically attached. number specifies the number of the
1842 display server on that host machine. screen_number specifies the
1843 screen to be used on that server.
1844 If unspecified, it defaults to the value of the DISPLAY environment
1846 variable.
1847 For example, "dual-headed:0.1" would specify screen 1 of display 0
1849 on the machine named ``dual-headed''.
1850 Check the X11 specification for more detailed information about the
1852 display name format.
1853 window_id
1855 When set to non-zero value then device doesn't create new window,
1856 but uses existing one with provided window_id. By default this
1857 options is set to zero and device creates its own window.
1858 window_size
1860 Set the created window size, can be a string of the form
1861 widthxheight or a video size abbreviation. If not specified it
1862 defaults to the size of the input video. Ignored when window_id is
1863 set.
1864 window_x
1866 window_y
1867 Set the X and Y window offsets for the created window. They are
1868 both set to 0 by default. The values may be ignored by the window
1869 manager. Ignored when window_id is set.
1870 window_title
1872 Set the window title, if not specified default to the filename
1873 specified for the output device. Ignored when window_id is set.
1874 For more information about XVideo see <http://www.x.org/>.
1876 Examples
1878 • Decode, display and encode video input with ffmpeg at the same
1880 time:
1881 ffmpeg -i INPUT OUTPUT -f xv display
1883 • Decode and display the input video to multiple X11 windows:
1885 ffmpeg -i INPUT -f xv normal -vf negate -f xv negated
1887
1889 ffmpeg(1), ffplay(1), ffprobe(1), libavdevice(3)
1890
1892 The FFmpeg developers.
1893 For details about the authorship, see the Git history of the project
1895 (git://source.ffmpeg.org/ffmpeg), e.g. by typing the command git log in
1896 the FFmpeg source directory, or browsing the online repository at
1897 <http://source.ffmpeg.org>.
1898 Maintainers for the specific components are listed in the file
1900 MAINTAINERS in the source code tree.
1901 FFMPEG-DEVICES(1)