V4L2-CTL(1)

NAME
v4l2-ctl - An application to control video4linux drivers

SYNOPSIS
v4l2-ctl [-h] [-d <dev>] [many other options]

DESCRIPTION
The v4l2-ctl tool is used to control video4linux devices, either video, vbi, radio or swradio, both input and output. It is able to control almost any aspect of such devices covering the full V4L2 API.

OPTIONS

-A, --list-devices
    List all v4l devices. If -z was given, then list just the devices of the media device with the bus info string as specified by the -z option.

-d, --device <dev>
    Use device <dev> as the V4L2 device. if <dev> starts with a digit, then /dev/video<dev> is used Otherwise if -z was specified earlier, then <dev> is the entity name or interface ID (if prefixed with 0x) as found in the topology of the media device with the bus info string as specified by the -z option.

-v, --verbose
    Turn on verbose reporting.

--version
    Show version information.

-w, --wrapper
    Use the libv4l2 wrapper library for all V4L2 device accesses. By default v4l2-ctl will directly access the V4L2 device, but with this option all access will go via this wrapper library.

-h, --help
    Prints the help message.

--help-io
    Prints the help message for all options that get/set/list inputs and outputs, both video and audio.

--help-meta
    Prints the help message for all options that get/set/list metadata formats.

--help-misc
    Prints the help message for miscellaneous options.

--help-overlay
    Prints the help message for all options that get/set/list overlay and framebuffer formats.

--help-sdr
    Prints the help message for all options that get/set/list software defined radio formats.

--help-selection
    Prints the help message for all options that deal with selections (cropping and composing).

--help-stds
    Prints the help message for all options that deal with SDTV standards and Digital Video timings.

--help-streaming
    Prints the help message for all options that deal with streaming.

--help-subdev
    Prints the help message for all options that deal with v4l-subdevX devices.

--help-tuner
    Prints the help message for all options that deal with tuners and modulators.

--help-vbi
    Prints the help message for all options that get/set/list VBI formats.

--help-vidcap
    Prints the help message for all options that get/set/list video capture formats.

--help-vidout
    Prints the help message for all options that get/set/list video output formats.

--help-edid
    Prints the help message for all options that get/set EDIDs.

--help-all
    Prints the help message for all options.

--all
    Display all information available.

-C, --get-ctrl <ctrl>[,<ctrl>...]
    Get the value of the controls [VIDIOC_G_EXT_CTRLS].

-c, --set-ctrl <ctrl>=<val>[,<ctrl>=<val>...]
    Set the value of the controls [VIDIOC_S_EXT_CTRLS].

-D, --info
    Show driver info [VIDIOC_QUERYCAP].

-e, --out-device <dev>
    Use device <dev> for output streams instead of the default device as set with --device. If <dev> starts with a digit, then /dev/video<dev> is used. Otherwise if -z was specified earlier, then <dev> is the entity name or interface ID (if prefixed with 0x) as found in the topology of the media device with the bus info string as specified by the -z option.

-E, --export-device <dev>
    Use device <dev> for exporting DMA buffers. If <dev> starts with a digit, then /dev/video<dev> is used. Otherwise if -z was specified earlier, then <dev> is the entity name or interface ID (if prefixed with 0x) as found in the topology of the media device with the bus info string as specified by the -z option.

-z, --media-bus-info <bus-info>
    Find the media device with the given <bus-info> string. If set, then -d, -e and -E options can use the entity name or interface ID to refer to the device nodes. Example: v4l2-ctl -z platform:vivid-000 -d vivid-000-vid-cap

-k, --concise
    Be more concise if possible.

-l, --list-ctrls
    Display all controls and their values [VIDIOC_QUERYCTRL].

-L, --list-ctrls-menus
    Display all controls and their menus [VIDIOC_QUERYMENU].

-r, --subset <ctrl>[,<offset>,<size>]+
    The subset of the N-dimensional array to get/set for control <ctrl>, for every dimension an (<offset>, <size>) tuple is given.

--list-devices-input <name>
    Same as --list-devices, but only show devices with a current input name that matches <name>.

--list-devices-output <name>
    Same as --list-devices, but only show devices with a current output name that matches <name>.

--log-status
    Log the board status in the kernel log [VIDIOC_LOG_STATUS].

--get-priority
    Query the current access priority [VIDIOC_G_PRIORITY].

--set-priority <prio>
    Set the new access priority [VIDIOC_S_PRIORITY]. <prio> is 1 (background), 2 (interactive) or 3 (record).

--silent
    Only set the result code, do not print any messages.

--sleep <secs>
    Sleep <secs>, call QUERYCAP and close the file handle.

EXIT STATUS
On success, it returns 0. Otherwise, it will return the error code.

EXAMPLES
Query the device information of /dev/video1:

    v4l2-ctl -d1 -D

Stream video using MMAP stream I/O from /dev/video0:

    v4l2-ctl -d0 --stream-mmap

Stream one frame of video from /dev/video0 and store it in a file:

    v4l2-ctl --stream-mmap --stream-count=1 --stream-to=file.raw

Stream video from /dev/video0 and stream it over the network:

    v4l2-ctl --stream-mmap --stream-to-host <hostname>

Use 'qvidcap -p' on the host to view the video.

Stream video from /dev/video0 using DMABUFs exported from /dev/video2:

    v4l2-ctl --stream-dmabuf --export-device /dev/video2

Stream video from a memory-to-memory device:

    v4l2-ctl --stream-mmap --stream-out-mmap

Stream video from a capture video device (/dev/video1) to an output video device (/dev/video2):

    v4l2-ctl -d1 --stream-mmap --out-device /dev/video2 --stream-out-dmabuf

BUGS
This manual page is a work in progress.

Bug reports or questions about this utility should be sent to the linux-media@vger.kernel.org mailinglist.