Man page - v4l2loopback-ctl(1)

Packages contains this manual

Manual

UNABLE

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
VERBS AND THEIR ARGUMENTS
v4l2loopback-ctl add [OPTIONS] [<outputdevice> [<capturedevice>]]:
v4l2loopback-ctl delete <device>:
v4l2loopback-ctl list [OPTIONS]:
v4l2loopback-ctl query [OPTIONS] <device>:
v4l2loopback-ctl set-fps <device> <fps>:
v4l2loopback-ctl get-fps <device>:
v4l2loopback-ctl set-caps <device> <caps>:
v4l2loopback-ctl get-caps <device>:
v4l2loopback-ctl set-timeout-image [OPTIONS] <device> <image>:
REPORTING BUGS

NAME

unable - control v4l2 loopback devices

SYNOPSIS

v4l2loopback-ctl [ OPTIONS ]
v4l2loopback-ctl add [ OPTIONS ] [ <outputdevice> [ <capturedevice> ]]
v4l2loopback-ctl delete <device>
v4l2loopback-ctl list [ OPTIONS ]
v4l2loopback-ctl query [ OPTIONS ] <device>
v4l2loopback-ctl set-fps <device> <fps>
v4l2loopback-ctl get-fps <device>
v4l2loopback-ctl set-caps <device> <caps>
v4l2loopback-ctl get-caps <device>
v4l2loopback-ctl set-timeout-image [ OPTIONS ] <device> <image>

DESCRIPTION

Manage v4l2 loopback devices.

The general invocation uses a verb (like ’add’ or ’delete’) that defines an action to be executed. Each verb has their own options and arguments.

OPTIONS

-h , -?, --help : print this help and exit

-v , --version : print version and exit

VERBS AND THEIR ARGUMENTS

v4l2loopback-ctl add [OPTIONS] [<outputdevice> [<capturedevice>]]:

create/add a new loopback-device

-b <num>, --buffers <num>

buffers to queue

-h <h>, --max-height <h>

maximum allowed frame height

-n <name>, --name <name>

pretty name for the device

-o <num>, --max-openers <num> maximum allowed concurrent openers

-v , --verbose

verbose mode (print properties of device after successfully creating it)

-w <w>, --max-width <w>

maximum allowed frame width

-x <x>, --exclusive-caps <x>

whether to announce OUTPUT/CAPTURE capabilities exclusively

--min-width <w>

minimum allowed frame width

--min-height <w>

minimum allowed frame height

-?, --help

print this help and exit

<outputdevice>

if given, create a specific device (otherwise just create a free one).

either specify a device name (e.g. ’/dev/video1’) or a device number (’1’).

<capturedevice>

if given, use separate output & capture devices (otherwise they are the same).

v4l2loopback-ctl delete <device>:

delete/remove an unused loopback device

<device>

can be given one more more times (to delete multiple devices at once). either specify a device name (e.g. ’/dev/video1’) or a device number (’1’).

v4l2loopback-ctl list [OPTIONS]:

list all available loopback-devices

-e , --escape

escape control-characters in (device) names

-h , --help

print this help and exit

v4l2loopback-ctl query [OPTIONS] <device>:

query information about a loopback device

-e , --escape

escape control-characters in (device) names

-h , --help

print this help and exit

<device>

can be given one more more times (to query multiple devices at once). either specify a device name (e.g. ’/dev/video1’) or a device number (’1’).

v4l2loopback-ctl set-fps <device> <fps>:

set the default framerate for a loopback device

<device>

either specify a device name (e.g. ’/dev/video1’) or a device number (’1’).

<fps>

frames per second, either as integer (’30’) or fraction (’50/2’).

v4l2loopback-ctl get-fps <device>:

query the framerate of a loopback device

v4l2loopback-ctl set-caps <device> <caps>:

set format/dimension/framerate of a loopback device

<device>

either specify a device name (e.g. ’/dev/video1’) or a device number (’1’).

<caps>

format specification as ’<fourcc>:<width>x<height>@<fps>’ (e.g. ’UYVY:1024x768@60/1’) unset the current caps with the special value ’any’

v4l2loopback-ctl get-caps <device>:

get current format/dimension/framerate of a loopback device

v4l2loopback-ctl set-timeout-image [OPTIONS] <device> <image>:

set a fallback image to be used if a video producer does not send new frames in time.

<flags>

any of the following flags may be present

-h , --help

print this help and exit

-t <timeout>, --timeout <timeout>

timeout (in ms)

-v , --verbose

raise verbosity (print what is being done)

<device>

either specify a device name (e.g. ’/dev/video1’) or a device number (’1’).

<image>

image file

REPORTING BUGS

Issue tracker: https://github.com/umlaeute/v4l2loopback/issues
Security Issue tracker: https://git.iem.at/zmoelnig/v4l2loopback/-/issues

utils/v4l2loopback-ctl v0.15.0