v4l2loopback-ctl - Man Page

control v4l2 loopback devices

Description

usage: utils/v4l2loopback-ctl [general commands]

general commands ================

-v/--version : print version and exit

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

add {<flags>} [<device> [<outputdevice>]]

delete <device>

list {<flags>}

query {<flags>} <device>

set-fps <device> <fps>

get-fps <device>

set-caps <device> <caps>

get-caps <device>

set-timeout-image {<flags>} <device> <image>

adding devices ('add') ======================

utils/v4l2loopback-ctl add {<flags>} [<device> [<outputdevice>]]

<flags>

any of the following flags may be present

-n/--name <name>

: pretty name for the device

--min-width <w>

: minimum allowed frame width

-w/--max-width <w>

: maximum allowed frame width

--min-height <w>

: minimum allowed frame height

-h/--max-height <h>

: maximum allowed frame height

-x/--exclusive-caps <x> : whether to announce OUTPUT/CAPTURE capabilities exclusively

-b/--buffers <num>

: buffers to queue

-o/--max-openers <num>

: maximum allowed concurrent openers

-v/--verbose

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

-?/--help

: print this help and exit

<device>

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').

<outputdevice>

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

deleting devices ('delete') ===========================

utils/v4l2loopback-ctl delete <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').

listing devices ('list') ========================

utils/v4l2loopback-ctl list {<flags>}

<flags>

any of the following flags may be present

-e/--escape

: escape control-characters in (device) names

-h/--help

: print this help and exit

list all available loopback-devices

querying devices ('query') ==========================

utils/v4l2loopback-ctl query {<flags>} <device>

<flags>

any of the following flags may be present

-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').

setting framerate ('set-fps') =============================

utils/v4l2loopback-ctl set-fps <device> <fps>

<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').

getting framerate ('get-fps') =============================

utils/v4l2loopback-ctl get-fps <device>

setting capabilities ('set-caps') =================================

utils/v4l2loopback-ctl set-caps <device> <caps>

<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')

getting capabilities ('get-caps') =================================

utils/v4l2loopback-ctl get-caps <device>

setting timeout image ('set-timeout-image') ===========================================

utils/v4l2loopback-ctl set-timeout-image {<flags>} <device> <image>

<flags>

any of the following flags may be present

-t/--timeout <timeout>

: timeout (in ms)

-v/--verbose

: raise verbosity (print what is being done)

-h/--help

: print this help and exit

<device>

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

<image>

image file

Info

February 2024 v4l2loopback-ctl v0.12.7