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wl-mirror(1)		     General Commands Manual		    wl-mirror(1)

NAME
     wl-mirror - a simple Wayland output mirror client

SYNOPSIS
     wl-mirror [-h,-V,-v,-c,-i,-f,-s S,-b B,-t T,-r R,-S] <output>

OPTIONS
     -h, --help
	 Show help message and exit.

     -V, --version
	 Show version information and exit.

     -v, --verbose
	 --no-verbose
	 Enable or disable debug logging.

     -c, --show-cursor
	 --no-show-cursor
	 Show the cursor on the mirrored surface (enabled by default).

     -i, --invert-colors
	 --no-invert-colors
	 Invert colors on the mirrored surface.

     -f, --freeze
	 --unfreeze
	 --toggle-freeze
	 Freeze,  unfreeze,  or  toggle  freezing  of  the  current image on the
	 screen.

     -F, --fullscreen
	 Open as a fullscreen window, or make the current window  fullscreen  in
	 stream mode.

	 --no-fullscreen
	 Open  as  a  regular window (enabled by default), or exit fullscreen in
	 stream mode.

	 --fullscreen-output O
	 Set a different output to fullscreen on (default is  the  current  out-
	 put), implies --fullscreen.

	 --no-fullscreen-output
	 Sets  the  target  fullscreen output back to the current window output,
	 implies --no-fullscreen.

     -s f, --scaling fit
	 Scale to fit and if necessary add letterboxing (enabled by default).

     -s c, --scaling cover
	 Scale to cover and if necessary crop the image.

     -s e, --scaling exact
	 Use exact multiple scaling and if necessary add letterboxing.

     -s l, --scaling linear
	 Use linear scaling (enabled by default).

     -s n, --scaling nearest
	 Use nearest-neighbor scaling.

     -b B, --backend B
	 Use a specific screen capture backend, see BACKENDS.

     -t T, --transform T
	 Apply custom transform (rotation and flipping), see TRANSFORMS.

     -r R, --region R
	 Capture custom screen region R, see REGIONS.

     -S, --stream
	 Accept a stream of additional options on stdin, see STREAM MODE.

     --title T
	 Specify a custom title T for the mirror window. This title can  contain
	 placeholders, see TITLE PLACEHOLDERS

BACKENDS
     auto
	 Automatically	try  backends in order of backend efficiency and use the
	 first that works (enabled by default). The next backend is selected au-
	 tomatically when the current backend fails to capture a frame 10  times
	 in a row.

	 The current fallback order is:

	 *   extcopy-dmabuf (if compiled with libGBM)
	 *   screencopy-dmabuf (if compiled with libGBM)
	 *   export-dmabuf
	 *   extcopy-shm
	 *   screencopy-shm

     export-dmabuf
	 Use  the wlr-export-dmabuf-unstable-v1 protocol to capture outputs (re-
	 quires wlroots). This backend keeps the image data on the GPU and  does
	 not need expensive copies to the CPU and back.

     screencopy-dmabuf
	 Use  the  wlr-screencopy-unstable-v1  protocol  to capture outputs (re-
	 quires wlroots) This backend keeps the image data on the GPU  and  does
	 not  need  expensive  copies to the CPU and back. This backend requires
	 wl-mirror to be compiled with support	for  allocating  DMA-BUFs  using
	 libGBM.

     screencopy-shm
	 Use  the  wlr-screencopy-unstable-v1  protocol  to capture outputs (re-
	 quires wlroots) This backend passes the image data via shared memory on
	 the CPU, but may have better compatibility with complex GPU driver con-
	 figurations (e.g., multi GPU).

     screencopy
	 Automatically tries screencopy-dmabuf or screencopy-shm  and  uses  the
	 first one that works. Fallback works the same as with auto.

     extcopy-dmabuf
	 Use  the  ext-image-copy-capture-v1  protocol	to  capture outputs This
	 backend keeps the image data on the GPU and  does  not  need  expensive
	 copies  to the CPU and back. This backend requires wl-mirror to be com-
	 piled with support for allocating DMA-BUFs using libGBM.

     extcopy-shm
	 Use the ext-image-copy-capture-v1  protocol  to  capture  outputs  This
	 backend  passes  the  image  data via shared memory on the CPU, but may
	 have better compatibility with complex GPU driver configurations (e.g.,
	 multi GPU).

     extcopy
	 Automatically tries extcopy-dmabuf or extcopy-shm and	uses  the  first
	 one that works. Fallback works the same as with auto.

TRANSFORMS
     Transforms  are  specified  as a dash-separated list of flips followed by a
     rotation amount. Flips are applied before rotations, both flips  and  rota-
     tions  are optional. Custom transformations are applied after adjusting for
     the wayland output transform, so that if no custom transformations are  ap-
     plied, the mirrored surface is displayed right-side-up.

     normal
	 No transformation (default transformation).

     flipX, flipY
	 Flip  the X or Y coordinate of the image, i.e. flipX means the mirrored
	 surface has left and right swapped.

     0cw, 90cw, 180cw, 270cw
	 Apply a clockwise rotation.

     0ccw, 90ccw, 180ccw, 270ccw
	 Apply a counter-clockwise rotation.

     The following transformation options are provided	for  compatibility  with
     sway-output(5) transforms:

     flipped
	 Same as flipX.

     0, 90, 180, 270
	 Same as 0cw, 90cw, 180cw, 270cw.

REGIONS
     Regions are specified in the format used by the slurp(1) utility:

	 'x,y widthxheight [output]'

     In  slurp(1) syntax, this would be specified as follows (the last part with
     %o is optional):

	 '%x,%y %wx%h %o'

     When processing the region option, the region is translated into output co-
     ordinates, so when the output moves, the captured	region	moves  with  it.
     When a region is specified, the output positional argument is optional.

STREAM MODE
     In  stream  mode, wl-mirror interprets lines on stdin as additional command
     line options.

     *	 Arguments can be quoted with single or double quotes, but  every  argu-
	 ment must be fully quoted.
     *	 Unquoted arguments are split on whitespace.
     *	 No escape sequences are implemented.

     Option  lines  on	stdin are processed asynchronously, and can override all
     options and the captured output. Stream mode is used  by  wl-present(1)  to
     add interactive controls to wl-mirror.

TITLE PLACEHOLDERS
     The title string supports the following placeholders:

     *	 {width}, {height}: size of the mirrored area
     *	 {x}, {y}: offsets on the screen
     *	 {target_width},  {target_height},  {target_output}: info about the mir-
	 rored device

     A few perhaps useful examples:

	 --title 'Wayland Mirror Output {target_output}'

	 --title '{target_output}:{width}x{height}+{x}+{y}'

	 --title 'resize set {width} {height} move position {x} {y}'

AUTHORS
     Maintained by Ferdinand Bachmann <ferdinand.bachmann@yrlf.at>. More  infor-
     mation  on  wl-mirror  can be found at <https://github.com/Ferdi265/wl-mir-
     ror>.

SEE ALSO
     wl-present(1) slurp(1) sway-output(5)

				   2026-08-29			    wl-mirror(1)
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