mirror of https://git.ffmpeg.org/ffmpeg.git
1412 lines
40 KiB
Plaintext
1412 lines
40 KiB
Plaintext
@chapter Input Devices
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@c man begin INPUT DEVICES
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Input devices are configured elements in FFmpeg which enable accessing
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the data coming from a multimedia device attached to your system.
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When you configure your FFmpeg build, all the supported input devices
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are enabled by default. You can list all available ones using the
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configure option "--list-indevs".
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You can disable all the input devices using the configure option
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"--disable-indevs", and selectively enable an input device using the
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option "--enable-indev=@var{INDEV}", or you can disable a particular
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input device using the option "--disable-indev=@var{INDEV}".
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The option "-devices" of the ff* tools will display the list of
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supported input devices.
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A description of the currently available input devices follows.
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@section alsa
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ALSA (Advanced Linux Sound Architecture) input device.
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To enable this input device during configuration you need libasound
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installed on your system.
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This device allows capturing from an ALSA device. The name of the
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device to capture has to be an ALSA card identifier.
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An ALSA identifier has the syntax:
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@example
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hw:@var{CARD}[,@var{DEV}[,@var{SUBDEV}]]
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@end example
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where the @var{DEV} and @var{SUBDEV} components are optional.
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The three arguments (in order: @var{CARD},@var{DEV},@var{SUBDEV})
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specify card number or identifier, device number and subdevice number
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(-1 means any).
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To see the list of cards currently recognized by your system check the
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files @file{/proc/asound/cards} and @file{/proc/asound/devices}.
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For example to capture with @command{ffmpeg} from an ALSA device with
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card id 0, you may run the command:
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@example
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ffmpeg -f alsa -i hw:0 alsaout.wav
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@end example
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For more information see:
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@url{http://www.alsa-project.org/alsa-doc/alsa-lib/pcm.html}
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@subsection Options
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@table @option
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@item sample_rate
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Set the sample rate in Hz. Default is 48000.
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@item channels
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Set the number of channels. Default is 2.
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@end table
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@section avfoundation
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AVFoundation input device.
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AVFoundation is the currently recommended framework by Apple for streamgrabbing on OSX >= 10.7 as well as on iOS.
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The older QTKit framework has been marked deprecated since OSX version 10.7.
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The input filename has to be given in the following syntax:
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@example
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-i "[[VIDEO]:[AUDIO]]"
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@end example
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The first entry selects the video input while the latter selects the audio input.
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The stream has to be specified by the device name or the device index as shown by the device list.
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Alternatively, the video and/or audio input device can be chosen by index using the
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@option{
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-video_device_index <INDEX>
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}
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and/or
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@option{
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-audio_device_index <INDEX>
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}
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, overriding any
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device name or index given in the input filename.
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All available devices can be enumerated by using @option{-list_devices true}, listing
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all device names and corresponding indices.
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There are two device name aliases:
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@table @code
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@item default
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Select the AVFoundation default device of the corresponding type.
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@item none
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Do not record the corresponding media type.
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This is equivalent to specifying an empty device name or index.
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@end table
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@subsection Options
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AVFoundation supports the following options:
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@table @option
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@item -list_devices <TRUE|FALSE>
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If set to true, a list of all available input devices is given showing all
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device names and indices.
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@item -video_device_index <INDEX>
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Specify the video device by its index. Overrides anything given in the input filename.
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@item -audio_device_index <INDEX>
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Specify the audio device by its index. Overrides anything given in the input filename.
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@item -pixel_format <FORMAT>
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Request the video device to use a specific pixel format.
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If the specified format is not supported, a list of available formats is given
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and the first one in this list is used instead. Available pixel formats are:
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@code{monob, rgb555be, rgb555le, rgb565be, rgb565le, rgb24, bgr24, 0rgb, bgr0, 0bgr, rgb0,
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bgr48be, uyvy422, yuva444p, yuva444p16le, yuv444p, yuv422p16, yuv422p10, yuv444p10,
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yuv420p, nv12, yuyv422, gray}
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@item -framerate
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Set the grabbing frame rate. Default is @code{ntsc}, corresponding to a
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frame rate of @code{30000/1001}.
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@item -video_size
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Set the video frame size.
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@item -capture_cursor
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Capture the mouse pointer. Default is 0.
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@item -capture_mouse_clicks
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Capture the screen mouse clicks. Default is 0.
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@end table
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@subsection Examples
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@itemize
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@item
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Print the list of AVFoundation supported devices and exit:
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@example
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$ ffmpeg -f avfoundation -list_devices true -i ""
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@end example
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@item
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Record video from video device 0 and audio from audio device 0 into out.avi:
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@example
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$ ffmpeg -f avfoundation -i "0:0" out.avi
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@end example
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@item
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Record video from video device 2 and audio from audio device 1 into out.avi:
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@example
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$ ffmpeg -f avfoundation -video_device_index 2 -i ":1" out.avi
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@end example
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@item
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Record video from the system default video device using the pixel format bgr0 and do not record any audio into out.avi:
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@example
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$ ffmpeg -f avfoundation -pixel_format bgr0 -i "default:none" out.avi
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@end example
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@end itemize
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@section bktr
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BSD video input device.
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@subsection Options
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@table @option
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@item framerate
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Set the frame rate.
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@item video_size
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Set the video frame size. Default is @code{vga}.
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@item standard
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Available values are:
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@table @samp
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@item pal
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@item ntsc
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@item secam
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@item paln
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@item palm
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@item ntscj
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@end table
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@end table
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@section decklink
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The decklink input device provides capture capabilities for Blackmagic
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DeckLink devices.
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To enable this input device, you need the Blackmagic DeckLink SDK and you
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need to configure with the appropriate @code{--extra-cflags}
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and @code{--extra-ldflags}.
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On Windows, you need to run the IDL files through @command{widl}.
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DeckLink is very picky about the formats it supports. Pixel format is
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uyvy422 or v210, framerate and video size must be determined for your device with
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@command{-list_formats 1}. Audio sample rate is always 48 kHz and the number
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of channels can be 2, 8 or 16. Note that all audio channels are bundled in one single
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audio track.
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@subsection Options
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@table @option
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@item list_devices
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If set to @option{true}, print a list of devices and exit.
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Defaults to @option{false}.
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@item list_formats
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If set to @option{true}, print a list of supported formats and exit.
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Defaults to @option{false}.
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@item bm_v210
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If set to @samp{1}, video is captured in 10 bit v210 instead
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of uyvy422. Not all Blackmagic devices support this option.
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@item teletext_lines
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If set to nonzero, an additional teletext stream will be captured from the
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vertical ancillary data. This option is a bitmask of the VBI lines checked,
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specifically lines 6 to 22, and lines 318 to 335. Line 6 is the LSB in the mask.
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Selected lines which do not contain teletext information will be ignored. You
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can use the special @option{all} constant to select all possible lines, or
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@option{standard} to skip lines 6, 318 and 319, which are not compatible with all
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receivers. Capturing teletext only works for SD PAL sources in 8 bit mode.
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To use this option, ffmpeg needs to be compiled with @code{--enable-libzvbi}.
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@item channels
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Defines number of audio channels to capture. Must be @samp{2}, @samp{8} or @samp{16}.
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Defaults to @samp{2}.
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@item duplex_mode
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Sets the decklink device duplex mode. Must be @samp{unset}, @samp{half} or @samp{full}.
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Defaults to @samp{unset}.
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@item video_input
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Sets the video input source. Must be @samp{unset}, @samp{sdi}, @samp{hdmi},
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@samp{optical_sdi}, @samp{component}, @samp{composite} or @samp{s_video}.
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Defaults to @samp{unset}.
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@item audio_input
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Sets the audio input source. Must be @samp{unset}, @samp{embedded},
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@samp{aes_ebu}, @samp{analog}, @samp{analog_xlr}, @samp{analog_rca} or
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@samp{microphone}. Defaults to @samp{unset}.
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@item video_pts
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Sets the video packet timestamp source. Must be @samp{video}, @samp{audio},
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@samp{reference} or @samp{wallclock}. Defaults to @samp{video}.
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@item audio_pts
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Sets the audio packet timestamp source. Must be @samp{video}, @samp{audio},
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@samp{reference} or @samp{wallclock}. Defaults to @samp{audio}.
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@item draw_bars
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If set to @samp{true}, color bars are drawn in the event of a signal loss.
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Defaults to @samp{true}.
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@end table
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@subsection Examples
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@itemize
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@item
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List input devices:
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@example
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ffmpeg -f decklink -list_devices 1 -i dummy
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@end example
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@item
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List supported formats:
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@example
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ffmpeg -f decklink -list_formats 1 -i 'Intensity Pro'
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@end example
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@item
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Capture video clip at 1080i50 (format 11):
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@example
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ffmpeg -f decklink -i 'Intensity Pro@@11' -acodec copy -vcodec copy output.avi
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@end example
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@item
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Capture video clip at 1080i50 10 bit:
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@example
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ffmpeg -bm_v210 1 -f decklink -i 'UltraStudio Mini Recorder@@11' -acodec copy -vcodec copy output.avi
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@end example
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@item
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Capture video clip at 1080i50 with 16 audio channels:
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@example
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ffmpeg -channels 16 -f decklink -i 'UltraStudio Mini Recorder@@11' -acodec copy -vcodec copy output.avi
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@end example
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@end itemize
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@section dshow
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Windows DirectShow input device.
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DirectShow support is enabled when FFmpeg is built with the mingw-w64 project.
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Currently only audio and video devices are supported.
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Multiple devices may be opened as separate inputs, but they may also be
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opened on the same input, which should improve synchronism between them.
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The input name should be in the format:
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@example
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@var{TYPE}=@var{NAME}[:@var{TYPE}=@var{NAME}]
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@end example
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where @var{TYPE} can be either @var{audio} or @var{video},
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and @var{NAME} is the device's name or alternative name..
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@subsection Options
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If no options are specified, the device's defaults are used.
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If the device does not support the requested options, it will
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fail to open.
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@table @option
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@item video_size
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Set the video size in the captured video.
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@item framerate
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Set the frame rate in the captured video.
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@item sample_rate
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Set the sample rate (in Hz) of the captured audio.
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@item sample_size
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Set the sample size (in bits) of the captured audio.
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@item channels
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Set the number of channels in the captured audio.
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@item list_devices
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If set to @option{true}, print a list of devices and exit.
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@item list_options
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If set to @option{true}, print a list of selected device's options
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and exit.
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@item video_device_number
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Set video device number for devices with the same name (starts at 0,
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defaults to 0).
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@item audio_device_number
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Set audio device number for devices with the same name (starts at 0,
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defaults to 0).
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@item pixel_format
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Select pixel format to be used by DirectShow. This may only be set when
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the video codec is not set or set to rawvideo.
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@item audio_buffer_size
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Set audio device buffer size in milliseconds (which can directly
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impact latency, depending on the device).
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Defaults to using the audio device's
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default buffer size (typically some multiple of 500ms).
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Setting this value too low can degrade performance.
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See also
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@url{http://msdn.microsoft.com/en-us/library/windows/desktop/dd377582(v=vs.85).aspx}
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@item video_pin_name
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Select video capture pin to use by name or alternative name.
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@item audio_pin_name
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Select audio capture pin to use by name or alternative name.
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@item crossbar_video_input_pin_number
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Select video input pin number for crossbar device. This will be
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routed to the crossbar device's Video Decoder output pin.
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Note that changing this value can affect future invocations
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(sets a new default) until system reboot occurs.
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@item crossbar_audio_input_pin_number
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Select audio input pin number for crossbar device. This will be
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routed to the crossbar device's Audio Decoder output pin.
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Note that changing this value can affect future invocations
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(sets a new default) until system reboot occurs.
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@item show_video_device_dialog
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If set to @option{true}, before capture starts, popup a display dialog
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to the end user, allowing them to change video filter properties
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and configurations manually.
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Note that for crossbar devices, adjusting values in this dialog
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may be needed at times to toggle between PAL (25 fps) and NTSC (29.97)
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input frame rates, sizes, interlacing, etc. Changing these values can
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enable different scan rates/frame rates and avoiding green bars at
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the bottom, flickering scan lines, etc.
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Note that with some devices, changing these properties can also affect future
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invocations (sets new defaults) until system reboot occurs.
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@item show_audio_device_dialog
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If set to @option{true}, before capture starts, popup a display dialog
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to the end user, allowing them to change audio filter properties
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and configurations manually.
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@item show_video_crossbar_connection_dialog
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If set to @option{true}, before capture starts, popup a display
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dialog to the end user, allowing them to manually
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modify crossbar pin routings, when it opens a video device.
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@item show_audio_crossbar_connection_dialog
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If set to @option{true}, before capture starts, popup a display
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dialog to the end user, allowing them to manually
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modify crossbar pin routings, when it opens an audio device.
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@item show_analog_tv_tuner_dialog
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If set to @option{true}, before capture starts, popup a display
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dialog to the end user, allowing them to manually
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modify TV channels and frequencies.
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@item show_analog_tv_tuner_audio_dialog
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If set to @option{true}, before capture starts, popup a display
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dialog to the end user, allowing them to manually
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modify TV audio (like mono vs. stereo, Language A,B or C).
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@item audio_device_load
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Load an audio capture filter device from file instead of searching
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it by name. It may load additional parameters too, if the filter
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supports the serialization of its properties to.
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To use this an audio capture source has to be specified, but it can
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be anything even fake one.
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@item audio_device_save
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Save the currently used audio capture filter device and its
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parameters (if the filter supports it) to a file.
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If a file with the same name exists it will be overwritten.
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@item video_device_load
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Load a video capture filter device from file instead of searching
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it by name. It may load additional parameters too, if the filter
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supports the serialization of its properties to.
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To use this a video capture source has to be specified, but it can
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be anything even fake one.
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@item video_device_save
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Save the currently used video capture filter device and its
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parameters (if the filter supports it) to a file.
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If a file with the same name exists it will be overwritten.
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@end table
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@subsection Examples
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@itemize
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@item
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Print the list of DirectShow supported devices and exit:
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@example
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$ ffmpeg -list_devices true -f dshow -i dummy
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@end example
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@item
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Open video device @var{Camera}:
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@example
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$ ffmpeg -f dshow -i video="Camera"
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@end example
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@item
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Open second video device with name @var{Camera}:
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@example
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$ ffmpeg -f dshow -video_device_number 1 -i video="Camera"
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@end example
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@item
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Open video device @var{Camera} and audio device @var{Microphone}:
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@example
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$ ffmpeg -f dshow -i video="Camera":audio="Microphone"
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@end example
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@item
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Print the list of supported options in selected device and exit:
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@example
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$ ffmpeg -list_options true -f dshow -i video="Camera"
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@end example
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@item
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Specify pin names to capture by name or alternative name, specify alternative device name:
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@example
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$ 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"
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@end example
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@item
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Configure a crossbar device, specifying crossbar pins, allow user to adjust video capture properties at startup:
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@example
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$ ffmpeg -f dshow -show_video_device_dialog true -crossbar_video_input_pin_number 0
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-crossbar_audio_input_pin_number 3 -i video="AVerMedia BDA Analog Capture":audio="AVerMedia BDA Analog Capture"
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@end example
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@end itemize
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@section dv1394
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Linux DV 1394 input device.
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@subsection Options
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@table @option
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@item framerate
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Set the frame rate. Default is 25.
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@item standard
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Available values are:
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@table @samp
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@item pal
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@item ntsc
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@end table
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Default value is @code{ntsc}.
|
|
|
|
@end table
|
|
|
|
@section fbdev
|
|
|
|
Linux framebuffer input device.
|
|
|
|
The Linux framebuffer is a graphic hardware-independent abstraction
|
|
layer to show graphics on a computer monitor, typically on the
|
|
console. It is accessed through a file device node, usually
|
|
@file{/dev/fb0}.
|
|
|
|
For more detailed information read the file
|
|
Documentation/fb/framebuffer.txt included in the Linux source tree.
|
|
|
|
See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
|
|
|
|
To record from the framebuffer device @file{/dev/fb0} with
|
|
@command{ffmpeg}:
|
|
@example
|
|
ffmpeg -f fbdev -framerate 10 -i /dev/fb0 out.avi
|
|
@end example
|
|
|
|
You can take a single screenshot image with the command:
|
|
@example
|
|
ffmpeg -f fbdev -framerate 1 -i /dev/fb0 -frames:v 1 screenshot.jpeg
|
|
@end example
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item framerate
|
|
Set the frame rate. Default is 25.
|
|
|
|
@end table
|
|
|
|
@section gdigrab
|
|
|
|
Win32 GDI-based screen capture device.
|
|
|
|
This device allows you to capture a region of the display on Windows.
|
|
|
|
There are two options for the input filename:
|
|
@example
|
|
desktop
|
|
@end example
|
|
or
|
|
@example
|
|
title=@var{window_title}
|
|
@end example
|
|
|
|
The first option will capture the entire desktop, or a fixed region of the
|
|
desktop. The second option will instead capture the contents of a single
|
|
window, regardless of its position on the screen.
|
|
|
|
For example, to grab the entire desktop using @command{ffmpeg}:
|
|
@example
|
|
ffmpeg -f gdigrab -framerate 6 -i desktop out.mpg
|
|
@end example
|
|
|
|
Grab a 640x480 region at position @code{10,20}:
|
|
@example
|
|
ffmpeg -f gdigrab -framerate 6 -offset_x 10 -offset_y 20 -video_size vga -i desktop out.mpg
|
|
@end example
|
|
|
|
Grab the contents of the window named "Calculator"
|
|
@example
|
|
ffmpeg -f gdigrab -framerate 6 -i title=Calculator out.mpg
|
|
@end example
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
@item draw_mouse
|
|
Specify whether to draw the mouse pointer. Use the value @code{0} to
|
|
not draw the pointer. Default value is @code{1}.
|
|
|
|
@item framerate
|
|
Set the grabbing frame rate. Default value is @code{ntsc},
|
|
corresponding to a frame rate of @code{30000/1001}.
|
|
|
|
@item show_region
|
|
Show grabbed region on screen.
|
|
|
|
If @var{show_region} is specified with @code{1}, then the grabbing
|
|
region will be indicated on screen. With this option, it is easy to
|
|
know what is being grabbed if only a portion of the screen is grabbed.
|
|
|
|
Note that @var{show_region} is incompatible with grabbing the contents
|
|
of a single window.
|
|
|
|
For example:
|
|
@example
|
|
ffmpeg -f gdigrab -show_region 1 -framerate 6 -video_size cif -offset_x 10 -offset_y 20 -i desktop out.mpg
|
|
@end example
|
|
|
|
@item video_size
|
|
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.
|
|
|
|
@item offset_x
|
|
When capturing a region with @var{video_size}, set the distance from the left edge of the screen or desktop.
|
|
|
|
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.
|
|
|
|
@item offset_y
|
|
When capturing a region with @var{video_size}, set the distance from the top edge of the screen or desktop.
|
|
|
|
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.
|
|
|
|
@end table
|
|
|
|
@section iec61883
|
|
|
|
FireWire DV/HDV input device using libiec61883.
|
|
|
|
To enable this input device, you need libiec61883, libraw1394 and
|
|
libavc1394 installed on your system. Use the configure option
|
|
@code{--enable-libiec61883} to compile with the device enabled.
|
|
|
|
The iec61883 capture device supports capturing from a video device
|
|
connected via IEEE1394 (FireWire), using libiec61883 and the new Linux
|
|
FireWire stack (juju). This is the default DV/HDV input method in Linux
|
|
Kernel 2.6.37 and later, since the old FireWire stack was removed.
|
|
|
|
Specify the FireWire port to be used as input file, or "auto"
|
|
to choose the first port connected.
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item dvtype
|
|
Override autodetection of DV/HDV. This should only be used if auto
|
|
detection does not work, or if usage of a different device type
|
|
should be prohibited. Treating a DV device as HDV (or vice versa) will
|
|
not work and result in undefined behavior.
|
|
The values @option{auto}, @option{dv} and @option{hdv} are supported.
|
|
|
|
@item dvbuffer
|
|
Set maximum size of buffer for incoming data, in frames. For DV, this
|
|
is an exact value. For HDV, it is not frame exact, since HDV does
|
|
not have a fixed frame size.
|
|
|
|
@item dvguid
|
|
Select the capture device by specifying its GUID. Capturing will only
|
|
be performed from the specified device and fails if no device with the
|
|
given GUID is found. This is useful to select the input if multiple
|
|
devices are connected at the same time.
|
|
Look at /sys/bus/firewire/devices to find out the GUIDs.
|
|
|
|
@end table
|
|
|
|
@subsection Examples
|
|
|
|
@itemize
|
|
|
|
@item
|
|
Grab and show the input of a FireWire DV/HDV device.
|
|
@example
|
|
ffplay -f iec61883 -i auto
|
|
@end example
|
|
|
|
@item
|
|
Grab and record the input of a FireWire DV/HDV device,
|
|
using a packet buffer of 100000 packets if the source is HDV.
|
|
@example
|
|
ffmpeg -f iec61883 -i auto -hdvbuffer 100000 out.mpg
|
|
@end example
|
|
|
|
@end itemize
|
|
|
|
@section jack
|
|
|
|
JACK input device.
|
|
|
|
To enable this input device during configuration you need libjack
|
|
installed on your system.
|
|
|
|
A JACK input device creates one or more JACK writable clients, one for
|
|
each audio channel, with name @var{client_name}:input_@var{N}, where
|
|
@var{client_name} is the name provided by the application, and @var{N}
|
|
is a number which identifies the channel.
|
|
Each writable client will send the acquired data to the FFmpeg input
|
|
device.
|
|
|
|
Once you have created one or more JACK readable clients, you need to
|
|
connect them to one or more JACK writable clients.
|
|
|
|
To connect or disconnect JACK clients you can use the @command{jack_connect}
|
|
and @command{jack_disconnect} programs, or do it through a graphical interface,
|
|
for example with @command{qjackctl}.
|
|
|
|
To list the JACK clients and their properties you can invoke the command
|
|
@command{jack_lsp}.
|
|
|
|
Follows an example which shows how to capture a JACK readable client
|
|
with @command{ffmpeg}.
|
|
@example
|
|
# Create a JACK writable client with name "ffmpeg".
|
|
$ ffmpeg -f jack -i ffmpeg -y out.wav
|
|
|
|
# Start the sample jack_metro readable client.
|
|
$ jack_metro -b 120 -d 0.2 -f 4000
|
|
|
|
# List the current JACK clients.
|
|
$ jack_lsp -c
|
|
system:capture_1
|
|
system:capture_2
|
|
system:playback_1
|
|
system:playback_2
|
|
ffmpeg:input_1
|
|
metro:120_bpm
|
|
|
|
# Connect metro to the ffmpeg writable client.
|
|
$ jack_connect metro:120_bpm ffmpeg:input_1
|
|
@end example
|
|
|
|
For more information read:
|
|
@url{http://jackaudio.org/}
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item channels
|
|
Set the number of channels. Default is 2.
|
|
|
|
@end table
|
|
|
|
@section lavfi
|
|
|
|
Libavfilter input virtual device.
|
|
|
|
This input device reads data from the open output pads of a libavfilter
|
|
filtergraph.
|
|
|
|
For each filtergraph open output, the input device will create a
|
|
corresponding stream which is mapped to the generated output. Currently
|
|
only video data is supported. The filtergraph is specified through the
|
|
option @option{graph}.
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item graph
|
|
Specify the filtergraph to use as input. Each video open output must be
|
|
labelled by a unique string of the form "out@var{N}", where @var{N} is a
|
|
number starting from 0 corresponding to the mapped input stream
|
|
generated by the device.
|
|
The first unlabelled output is automatically assigned to the "out0"
|
|
label, but all the others need to be specified explicitly.
|
|
|
|
The suffix "+subcc" can be appended to the output label to create an extra
|
|
stream with the closed captions packets attached to that output
|
|
(experimental; only for EIA-608 / CEA-708 for now).
|
|
The subcc streams are created after all the normal streams, in the order of
|
|
the corresponding stream.
|
|
For example, if there is "out19+subcc", "out7+subcc" and up to "out42", the
|
|
stream #43 is subcc for stream #7 and stream #44 is subcc for stream #19.
|
|
|
|
If not specified defaults to the filename specified for the input
|
|
device.
|
|
|
|
@item graph_file
|
|
Set the filename of the filtergraph to be read and sent to the other
|
|
filters. Syntax of the filtergraph is the same as the one specified by
|
|
the option @var{graph}.
|
|
|
|
@item dumpgraph
|
|
Dump graph to stderr.
|
|
|
|
@end table
|
|
|
|
@subsection Examples
|
|
|
|
@itemize
|
|
@item
|
|
Create a color video stream and play it back with @command{ffplay}:
|
|
@example
|
|
ffplay -f lavfi -graph "color=c=pink [out0]" dummy
|
|
@end example
|
|
|
|
@item
|
|
As the previous example, but use filename for specifying the graph
|
|
description, and omit the "out0" label:
|
|
@example
|
|
ffplay -f lavfi color=c=pink
|
|
@end example
|
|
|
|
@item
|
|
Create three different video test filtered sources and play them:
|
|
@example
|
|
ffplay -f lavfi -graph "testsrc [out0]; testsrc,hflip [out1]; testsrc,negate [out2]" test3
|
|
@end example
|
|
|
|
@item
|
|
Read an audio stream from a file using the amovie source and play it
|
|
back with @command{ffplay}:
|
|
@example
|
|
ffplay -f lavfi "amovie=test.wav"
|
|
@end example
|
|
|
|
@item
|
|
Read an audio stream and a video stream and play it back with
|
|
@command{ffplay}:
|
|
@example
|
|
ffplay -f lavfi "movie=test.avi[out0];amovie=test.wav[out1]"
|
|
@end example
|
|
|
|
@item
|
|
Dump decoded frames to images and closed captions to a file (experimental):
|
|
@example
|
|
ffmpeg -f lavfi -i "movie=test.ts[out0+subcc]" -map v frame%08d.png -map s -c copy -f rawvideo subcc.bin
|
|
@end example
|
|
|
|
@end itemize
|
|
|
|
@section libcdio
|
|
|
|
Audio-CD input device based on libcdio.
|
|
|
|
To enable this input device during configuration you need libcdio
|
|
installed on your system. It requires the configure option
|
|
@code{--enable-libcdio}.
|
|
|
|
This device allows playing and grabbing from an Audio-CD.
|
|
|
|
For example to copy with @command{ffmpeg} the entire Audio-CD in @file{/dev/sr0},
|
|
you may run the command:
|
|
@example
|
|
ffmpeg -f libcdio -i /dev/sr0 cd.wav
|
|
@end example
|
|
|
|
@subsection Options
|
|
@table @option
|
|
@item speed
|
|
Set drive reading speed. Default value is 0.
|
|
|
|
The speed is specified CD-ROM speed units. The speed is set through
|
|
the libcdio @code{cdio_cddap_speed_set} function. On many CD-ROM
|
|
drives, specifying a value too large will result in using the fastest
|
|
speed.
|
|
|
|
@item paranoia_mode
|
|
Set paranoia recovery mode flags. It accepts one of the following values:
|
|
|
|
@table @samp
|
|
@item disable
|
|
@item verify
|
|
@item overlap
|
|
@item neverskip
|
|
@item full
|
|
@end table
|
|
|
|
Default value is @samp{disable}.
|
|
|
|
For more information about the available recovery modes, consult the
|
|
paranoia project documentation.
|
|
@end table
|
|
|
|
@section libdc1394
|
|
|
|
IIDC1394 input device, based on libdc1394 and libraw1394.
|
|
|
|
Requires the configure option @code{--enable-libdc1394}.
|
|
|
|
@section openal
|
|
|
|
The OpenAL input device provides audio capture on all systems with a
|
|
working OpenAL 1.1 implementation.
|
|
|
|
To enable this input device during configuration, you need OpenAL
|
|
headers and libraries installed on your system, and need to configure
|
|
FFmpeg with @code{--enable-openal}.
|
|
|
|
OpenAL headers and libraries should be provided as part of your OpenAL
|
|
implementation, or as an additional download (an SDK). Depending on your
|
|
installation you may need to specify additional flags via the
|
|
@code{--extra-cflags} and @code{--extra-ldflags} for allowing the build
|
|
system to locate the OpenAL headers and libraries.
|
|
|
|
An incomplete list of OpenAL implementations follows:
|
|
|
|
@table @strong
|
|
@item Creative
|
|
The official Windows implementation, providing hardware acceleration
|
|
with supported devices and software fallback.
|
|
See @url{http://openal.org/}.
|
|
@item OpenAL Soft
|
|
Portable, open source (LGPL) software implementation. Includes
|
|
backends for the most common sound APIs on the Windows, Linux,
|
|
Solaris, and BSD operating systems.
|
|
See @url{http://kcat.strangesoft.net/openal.html}.
|
|
@item Apple
|
|
OpenAL is part of Core Audio, the official Mac OS X Audio interface.
|
|
See @url{http://developer.apple.com/technologies/mac/audio-and-video.html}
|
|
@end table
|
|
|
|
This device allows one to capture from an audio input device handled
|
|
through OpenAL.
|
|
|
|
You need to specify the name of the device to capture in the provided
|
|
filename. If the empty string is provided, the device will
|
|
automatically select the default device. You can get the list of the
|
|
supported devices by using the option @var{list_devices}.
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item channels
|
|
Set the number of channels in the captured audio. Only the values
|
|
@option{1} (monaural) and @option{2} (stereo) are currently supported.
|
|
Defaults to @option{2}.
|
|
|
|
@item sample_size
|
|
Set the sample size (in bits) of the captured audio. Only the values
|
|
@option{8} and @option{16} are currently supported. Defaults to
|
|
@option{16}.
|
|
|
|
@item sample_rate
|
|
Set the sample rate (in Hz) of the captured audio.
|
|
Defaults to @option{44.1k}.
|
|
|
|
@item list_devices
|
|
If set to @option{true}, print a list of devices and exit.
|
|
Defaults to @option{false}.
|
|
|
|
@end table
|
|
|
|
@subsection Examples
|
|
|
|
Print the list of OpenAL supported devices and exit:
|
|
@example
|
|
$ ffmpeg -list_devices true -f openal -i dummy out.ogg
|
|
@end example
|
|
|
|
Capture from the OpenAL device @file{DR-BT101 via PulseAudio}:
|
|
@example
|
|
$ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out.ogg
|
|
@end example
|
|
|
|
Capture from the default device (note the empty string '' as filename):
|
|
@example
|
|
$ ffmpeg -f openal -i '' out.ogg
|
|
@end example
|
|
|
|
Capture from two devices simultaneously, writing to two different files,
|
|
within the same @command{ffmpeg} command:
|
|
@example
|
|
$ ffmpeg -f openal -i 'DR-BT101 via PulseAudio' out1.ogg -f openal -i 'ALSA Default' out2.ogg
|
|
@end example
|
|
Note: not all OpenAL implementations support multiple simultaneous capture -
|
|
try the latest OpenAL Soft if the above does not work.
|
|
|
|
@section oss
|
|
|
|
Open Sound System input device.
|
|
|
|
The filename to provide to the input device is the device node
|
|
representing the OSS input device, and is usually set to
|
|
@file{/dev/dsp}.
|
|
|
|
For example to grab from @file{/dev/dsp} using @command{ffmpeg} use the
|
|
command:
|
|
@example
|
|
ffmpeg -f oss -i /dev/dsp /tmp/oss.wav
|
|
@end example
|
|
|
|
For more information about OSS see:
|
|
@url{http://manuals.opensound.com/usersguide/dsp.html}
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item sample_rate
|
|
Set the sample rate in Hz. Default is 48000.
|
|
|
|
@item channels
|
|
Set the number of channels. Default is 2.
|
|
|
|
@end table
|
|
|
|
|
|
@section pulse
|
|
|
|
PulseAudio input device.
|
|
|
|
To enable this output device you need to configure FFmpeg with @code{--enable-libpulse}.
|
|
|
|
The filename to provide to the input device is a source device or the
|
|
string "default"
|
|
|
|
To list the PulseAudio source devices and their properties you can invoke
|
|
the command @command{pactl list sources}.
|
|
|
|
More information about PulseAudio can be found on @url{http://www.pulseaudio.org}.
|
|
|
|
@subsection Options
|
|
@table @option
|
|
@item server
|
|
Connect to a specific PulseAudio server, specified by an IP address.
|
|
Default server is used when not provided.
|
|
|
|
@item name
|
|
Specify the application name PulseAudio will use when showing active clients,
|
|
by default it is the @code{LIBAVFORMAT_IDENT} string.
|
|
|
|
@item stream_name
|
|
Specify the stream name PulseAudio will use when showing active streams,
|
|
by default it is "record".
|
|
|
|
@item sample_rate
|
|
Specify the samplerate in Hz, by default 48kHz is used.
|
|
|
|
@item channels
|
|
Specify the channels in use, by default 2 (stereo) is set.
|
|
|
|
@item frame_size
|
|
Specify the number of bytes per frame, by default it is set to 1024.
|
|
|
|
@item fragment_size
|
|
Specify the minimal buffering fragment in PulseAudio, it will affect the
|
|
audio latency. By default it is unset.
|
|
|
|
@item wallclock
|
|
Set the initial PTS using the current time. Default is 1.
|
|
|
|
@end table
|
|
|
|
@subsection Examples
|
|
Record a stream from default device:
|
|
@example
|
|
ffmpeg -f pulse -i default /tmp/pulse.wav
|
|
@end example
|
|
|
|
@section qtkit
|
|
|
|
QTKit input device.
|
|
|
|
The filename passed as input is parsed to contain either a device name or index.
|
|
The device index can also be given by using -video_device_index.
|
|
A given device index will override any given device name.
|
|
If the desired device consists of numbers only, use -video_device_index to identify it.
|
|
The default device will be chosen if an empty string or the device name "default" is given.
|
|
The available devices can be enumerated by using -list_devices.
|
|
|
|
@example
|
|
ffmpeg -f qtkit -i "0" out.mpg
|
|
@end example
|
|
|
|
@example
|
|
ffmpeg -f qtkit -video_device_index 0 -i "" out.mpg
|
|
@end example
|
|
|
|
@example
|
|
ffmpeg -f qtkit -i "default" out.mpg
|
|
@end example
|
|
|
|
@example
|
|
ffmpeg -f qtkit -list_devices true -i ""
|
|
@end example
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item frame_rate
|
|
Set frame rate. Default is 30.
|
|
|
|
@item list_devices
|
|
If set to @code{true}, print a list of devices and exit. Default is
|
|
@code{false}.
|
|
|
|
@item video_device_index
|
|
Select the video device by index for devices with the same name (starts at 0).
|
|
|
|
@end table
|
|
|
|
@section sndio
|
|
|
|
sndio input device.
|
|
|
|
To enable this input device during configuration you need libsndio
|
|
installed on your system.
|
|
|
|
The filename to provide to the input device is the device node
|
|
representing the sndio input device, and is usually set to
|
|
@file{/dev/audio0}.
|
|
|
|
For example to grab from @file{/dev/audio0} using @command{ffmpeg} use the
|
|
command:
|
|
@example
|
|
ffmpeg -f sndio -i /dev/audio0 /tmp/oss.wav
|
|
@end example
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item sample_rate
|
|
Set the sample rate in Hz. Default is 48000.
|
|
|
|
@item channels
|
|
Set the number of channels. Default is 2.
|
|
|
|
@end table
|
|
|
|
@section video4linux2, v4l2
|
|
|
|
Video4Linux2 input video device.
|
|
|
|
"v4l2" can be used as alias for "video4linux2".
|
|
|
|
If FFmpeg is built with v4l-utils support (by using the
|
|
@code{--enable-libv4l2} configure option), it is possible to use it with the
|
|
@code{-use_libv4l2} input device option.
|
|
|
|
The name of the device to grab is a file device node, usually Linux
|
|
systems tend to automatically create such nodes when the device
|
|
(e.g. an USB webcam) is plugged into the system, and has a name of the
|
|
kind @file{/dev/video@var{N}}, where @var{N} is a number associated to
|
|
the device.
|
|
|
|
Video4Linux2 devices usually support a limited set of
|
|
@var{width}x@var{height} sizes and frame rates. You can check which are
|
|
supported using @command{-list_formats all} for Video4Linux2 devices.
|
|
Some devices, like TV cards, support one or more standards. It is possible
|
|
to list all the supported standards using @command{-list_standards all}.
|
|
|
|
The time base for the timestamps is 1 microsecond. Depending on the kernel
|
|
version and configuration, the timestamps may be derived from the real time
|
|
clock (origin at the Unix Epoch) or the monotonic clock (origin usually at
|
|
boot time, unaffected by NTP or manual changes to the clock). The
|
|
@option{-timestamps abs} or @option{-ts abs} option can be used to force
|
|
conversion into the real time clock.
|
|
|
|
Some usage examples of the video4linux2 device with @command{ffmpeg}
|
|
and @command{ffplay}:
|
|
@itemize
|
|
@item
|
|
List supported formats for a video4linux2 device:
|
|
@example
|
|
ffplay -f video4linux2 -list_formats all /dev/video0
|
|
@end example
|
|
|
|
@item
|
|
Grab and show the input of a video4linux2 device:
|
|
@example
|
|
ffplay -f video4linux2 -framerate 30 -video_size hd720 /dev/video0
|
|
@end example
|
|
|
|
@item
|
|
Grab and record the input of a video4linux2 device, leave the
|
|
frame rate and size as previously set:
|
|
@example
|
|
ffmpeg -f video4linux2 -input_format mjpeg -i /dev/video0 out.mpeg
|
|
@end example
|
|
@end itemize
|
|
|
|
For more information about Video4Linux, check @url{http://linuxtv.org/}.
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
@item standard
|
|
Set the standard. Must be the name of a supported standard. To get a
|
|
list of the supported standards, use the @option{list_standards}
|
|
option.
|
|
|
|
@item channel
|
|
Set the input channel number. Default to -1, which means using the
|
|
previously selected channel.
|
|
|
|
@item video_size
|
|
Set the video frame size. The argument must be a string in the form
|
|
@var{WIDTH}x@var{HEIGHT} or a valid size abbreviation.
|
|
|
|
@item pixel_format
|
|
Select the pixel format (only valid for raw video input).
|
|
|
|
@item input_format
|
|
Set the preferred pixel format (for raw video) or a codec name.
|
|
This option allows one to select the input format, when several are
|
|
available.
|
|
|
|
@item framerate
|
|
Set the preferred video frame rate.
|
|
|
|
@item list_formats
|
|
List available formats (supported pixel formats, codecs, and frame
|
|
sizes) and exit.
|
|
|
|
Available values are:
|
|
@table @samp
|
|
@item all
|
|
Show all available (compressed and non-compressed) formats.
|
|
|
|
@item raw
|
|
Show only raw video (non-compressed) formats.
|
|
|
|
@item compressed
|
|
Show only compressed formats.
|
|
@end table
|
|
|
|
@item list_standards
|
|
List supported standards and exit.
|
|
|
|
Available values are:
|
|
@table @samp
|
|
@item all
|
|
Show all supported standards.
|
|
@end table
|
|
|
|
@item timestamps, ts
|
|
Set type of timestamps for grabbed frames.
|
|
|
|
Available values are:
|
|
@table @samp
|
|
@item default
|
|
Use timestamps from the kernel.
|
|
|
|
@item abs
|
|
Use absolute timestamps (wall clock).
|
|
|
|
@item mono2abs
|
|
Force conversion from monotonic to absolute timestamps.
|
|
@end table
|
|
|
|
Default value is @code{default}.
|
|
|
|
@item use_libv4l2
|
|
Use libv4l2 (v4l-utils) conversion functions. Default is 0.
|
|
|
|
@end table
|
|
|
|
@section vfwcap
|
|
|
|
VfW (Video for Windows) capture input device.
|
|
|
|
The filename passed as input is the capture driver number, ranging from
|
|
0 to 9. You may use "list" as filename to print a list of drivers. Any
|
|
other filename will be interpreted as device number 0.
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
|
|
@item video_size
|
|
Set the video frame size.
|
|
|
|
@item framerate
|
|
Set the grabbing frame rate. Default value is @code{ntsc},
|
|
corresponding to a frame rate of @code{30000/1001}.
|
|
|
|
@end table
|
|
|
|
@section x11grab
|
|
|
|
X11 video input device.
|
|
|
|
To enable this input device during configuration you need libxcb
|
|
installed on your system. It will be automatically detected during
|
|
configuration.
|
|
|
|
Alternatively, the configure option @option{--enable-x11grab} exists
|
|
for legacy Xlib users.
|
|
|
|
This device allows one to capture a region of an X11 display.
|
|
|
|
The filename passed as input has the syntax:
|
|
@example
|
|
[@var{hostname}]:@var{display_number}.@var{screen_number}[+@var{x_offset},@var{y_offset}]
|
|
@end example
|
|
|
|
@var{hostname}:@var{display_number}.@var{screen_number} specifies the
|
|
X11 display name of the screen to grab from. @var{hostname} can be
|
|
omitted, and defaults to "localhost". The environment variable
|
|
@env{DISPLAY} contains the default display name.
|
|
|
|
@var{x_offset} and @var{y_offset} specify the offsets of the grabbed
|
|
area with respect to the top-left border of the X11 screen. They
|
|
default to 0.
|
|
|
|
Check the X11 documentation (e.g. @command{man X}) for more detailed
|
|
information.
|
|
|
|
Use the @command{xdpyinfo} program for getting basic information about
|
|
the properties of your X11 display (e.g. grep for "name" or
|
|
"dimensions").
|
|
|
|
For example to grab from @file{:0.0} using @command{ffmpeg}:
|
|
@example
|
|
ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0 out.mpg
|
|
@end example
|
|
|
|
Grab at position @code{10,20}:
|
|
@example
|
|
ffmpeg -f x11grab -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
|
|
@end example
|
|
|
|
@subsection Options
|
|
|
|
@table @option
|
|
@item draw_mouse
|
|
Specify whether to draw the mouse pointer. A value of @code{0} specifies
|
|
not to draw the pointer. Default value is @code{1}.
|
|
|
|
@item follow_mouse
|
|
Make the grabbed area follow the mouse. The argument can be
|
|
@code{centered} or a number of pixels @var{PIXELS}.
|
|
|
|
When it is specified with "centered", the grabbing region follows the mouse
|
|
pointer and keeps the pointer at the center of region; otherwise, the region
|
|
follows only when the mouse pointer reaches within @var{PIXELS} (greater than
|
|
zero) to the edge of region.
|
|
|
|
For example:
|
|
@example
|
|
ffmpeg -f x11grab -follow_mouse centered -framerate 25 -video_size cif -i :0.0 out.mpg
|
|
@end example
|
|
|
|
To follow only when the mouse pointer reaches within 100 pixels to edge:
|
|
@example
|
|
ffmpeg -f x11grab -follow_mouse 100 -framerate 25 -video_size cif -i :0.0 out.mpg
|
|
@end example
|
|
|
|
@item framerate
|
|
Set the grabbing frame rate. Default value is @code{ntsc},
|
|
corresponding to a frame rate of @code{30000/1001}.
|
|
|
|
@item show_region
|
|
Show grabbed region on screen.
|
|
|
|
If @var{show_region} is specified with @code{1}, then the grabbing
|
|
region will be indicated on screen. With this option, it is easy to
|
|
know what is being grabbed if only a portion of the screen is grabbed.
|
|
|
|
@item region_border
|
|
Set the region border thickness if @option{-show_region 1} is used.
|
|
Range is 1 to 128 and default is 3 (XCB-based x11grab only).
|
|
|
|
For example:
|
|
@example
|
|
ffmpeg -f x11grab -show_region 1 -framerate 25 -video_size cif -i :0.0+10,20 out.mpg
|
|
@end example
|
|
|
|
With @var{follow_mouse}:
|
|
@example
|
|
ffmpeg -f x11grab -follow_mouse centered -show_region 1 -framerate 25 -video_size cif -i :0.0 out.mpg
|
|
@end example
|
|
|
|
@item video_size
|
|
Set the video frame size. Default value is @code{vga}.
|
|
|
|
@item use_shm
|
|
Use the MIT-SHM extension for shared memory. Default value is @code{1}.
|
|
It may be necessary to disable it for remote displays (legacy x11grab
|
|
only).
|
|
|
|
@item grab_x
|
|
@item grab_y
|
|
Set the grabbing region coordinates. They are expressed as offset from
|
|
the top left corner of the X11 window and correspond to the
|
|
@var{x_offset} and @var{y_offset} parameters in the device name. The
|
|
default value for both options is 0.
|
|
@end table
|
|
|
|
@c man end INPUT DEVICES
|