mpv/DOCS/man/vo.rst

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VIDEO OUTPUT DRIVERS
====================
Video output drivers are interfaces to different video output facilities. The
syntax is:
``--vo=<driver1,driver2,...[,]>``
Specify a priority list of video output drivers to be used.
If the list has a trailing ``,``, mpv will fall back on drivers not contained
in the list.
.. note::
See ``--vo=help`` for a list of compiled-in video output drivers.
The recommended output driver is ``--vo=gpu``, which is the default. All
other drivers are for compatibility or special purposes. If the default
does not work, it will fallback to other drivers (in the same order as
listed by ``--vo=help``).
Available video output drivers are:
``xv`` (X11 only)
Uses the XVideo extension to enable hardware-accelerated display. This is
the most compatible VO on X, but may be low-quality, and has issues with
OSD and subtitle display.
.. note:: This driver is for compatibility with old systems.
The following global options are supported by this video output:
``--xv-adaptor=<number>``
Select a specific XVideo adapter (check xvinfo results).
``--xv-port=<number>``
Select a specific XVideo port.
``--xv-ck=<cur|use|set>``
Select the source from which the color key is taken (default: cur).
cur
The default takes the color key currently set in Xv.
use
Use but do not set the color key from mpv (use the ``--colorkey``
option to change it).
set
Same as use but also sets the supplied color key.
``--xv-ck-method=<none|man|bg|auto>``
Sets the color key drawing method (default: man).
none
Disables color-keying.
man
Draw the color key manually (reduces flicker in some cases).
bg
Set the color key as window background.
auto
Let Xv draw the color key.
``--xv-colorkey=<number>``
Changes the color key to an RGB value of your choice. ``0x000000`` is
black and ``0xffffff`` is white.
``--xv-buffers=<number>``
Number of image buffers to use for the internal ringbuffer (default: 2).
Increasing this will use more memory, but might help with the X server
not responding quickly enough if video FPS is close to or higher than
the display refresh rate.
``x11`` (X11 only)
Shared memory video output driver without hardware acceleration that works
whenever X11 is present.
Since mpv 0.30.0, you may need to use ``--profile=sw-fast`` to get decent
performance.
.. note:: This is a fallback only, and should not be normally used.
``vdpau`` (X11 only)
Uses the VDPAU interface to display and optionally also decode video.
Hardware decoding is used with ``--hwdec=vdpau``.
.. note::
Earlier versions of mpv (and MPlayer, mplayer2) provided sub-options
to tune vdpau post-processing, like ``deint``, ``sharpen``, ``denoise``,
``chroma-deint``, ``pullup``, ``hqscaling``. These sub-options are
deprecated, and you should use the ``vdpaupp`` video filter instead.
The following global options are supported by this video output:
``--vo-vdpau-sharpen=<-1-1>``
(Deprecated. See note about ``vdpaupp``.)
For positive values, apply a sharpening algorithm to the video, for
negative values a blurring algorithm (default: 0).
``--vo-vdpau-denoise=<0-1>``
(Deprecated. See note about ``vdpaupp``.)
Apply a noise reduction algorithm to the video (default: 0; no noise
reduction).
``--vo-vdpau-chroma-deint``
(Deprecated. See note about ``vdpaupp``.)
Makes temporal deinterlacers operate both on luma and chroma (default).
Use no-chroma-deint to solely use luma and speed up advanced
deinterlacing. Useful with slow video memory.
``--vo-vdpau-pullup``
(Deprecated. See note about ``vdpaupp``.)
Try to apply inverse telecine, needs motion adaptive temporal
deinterlacing.
``--vo-vdpau-hqscaling=<0-9>``
(Deprecated. See note about ``vdpaupp``.)
0
Use default VDPAU scaling (default).
1-9
Apply high quality VDPAU scaling (needs capable hardware).
``--vo-vdpau-fps=<number>``
Override autodetected display refresh rate value (the value is needed
for framedrop to allow video playback rates higher than display
refresh rate, and for vsync-aware frame timing adjustments). Default 0
means use autodetected value. A positive value is interpreted as a
refresh rate in Hz and overrides the autodetected value. A negative
value disables all timing adjustment and framedrop logic.
``--vo-vdpau-composite-detect``
NVIDIA's current VDPAU implementation behaves somewhat differently
under a compositing window manager and does not give accurate frame
timing information. With this option enabled, the player tries to
detect whether a compositing window manager is active. If one is
detected, the player disables timing adjustments as if the user had
specified ``fps=-1`` (as they would be based on incorrect input). This
means timing is somewhat less accurate than without compositing, but
with the composited mode behavior of the NVIDIA driver, there is no
hard playback speed limit even without the disabled logic. Enabled by
default, use ``--vo-vdpau-composite-detect=no`` to disable.
``--vo-vdpau-queuetime-windowed=<number>`` and ``queuetime-fs=<number>``
Use VDPAU's presentation queue functionality to queue future video
frame changes at most this many milliseconds in advance (default: 50).
See below for additional information.
``--vo-vdpau-output-surfaces=<2-15>``
Allocate this many output surfaces to display video frames (default:
3). See below for additional information.
``--vo-vdpau-colorkey=<#RRGGBB|#AARRGGBB>``
Set the VDPAU presentation queue background color, which in practice
is the colorkey used if VDPAU operates in overlay mode (default:
``#020507``, some shade of black). If the alpha component of this value
is 0, the default VDPAU colorkey will be used instead (which is usually
green).
``--vo-vdpau-force-yuv``
Never accept RGBA input. This means mpv will insert a filter to convert
to a YUV format before the VO. Sometimes useful to force availability
of certain YUV-only features, like video equalizer or deinterlacing.
Using the VDPAU frame queuing functionality controlled by the queuetime
options makes mpv's frame flip timing less sensitive to system CPU load and
allows mpv to start decoding the next frame(s) slightly earlier, which can
reduce jitter caused by individual slow-to-decode frames. However, the
NVIDIA graphics drivers can make other window behavior such as window moves
choppy if VDPAU is using the blit queue (mainly happens if you have the
composite extension enabled) and this feature is active. If this happens on
your system and it bothers you then you can set the queuetime value to 0 to
disable this feature. The settings to use in windowed and fullscreen mode
are separate because there should be no reason to disable this for
fullscreen mode (as the driver issue should not affect the video itself).
You can queue more frames ahead by increasing the queuetime values and the
``output_surfaces`` count (to ensure enough surfaces to buffer video for a
certain time ahead you need at least as many surfaces as the video has
frames during that time, plus two). This could help make video smoother in
some cases. The main downsides are increased video RAM requirements for
the surfaces and laggier display response to user commands (display
changes only become visible some time after they're queued). The graphics
driver implementation may also have limits on the length of maximum
queuing time or number of queued surfaces that work well or at all.
``direct3d`` (Windows only)
Video output driver that uses the Direct3D interface.
.. note:: This driver is for compatibility with systems that don't provide
proper OpenGL drivers, and where ANGLE does not perform well.
The following global options are supported by this video output:
``--vo-direct3d-disable-texture-align``
Normally texture sizes are always aligned to 16. With this option
enabled, the video texture will always have exactly the same size as
the video itself.
Debug options. These might be incorrect, might be removed in the future,
might crash, might cause slow downs, etc. Contact the developers if you
actually need any of these for performance or proper operation.
``--vo-direct3d-force-power-of-2``
Always force textures to power of 2, even if the device reports
non-power-of-2 texture sizes as supported.
``--vo-direct3d-texture-memory=<mode>``
Only affects operation with shaders/texturing enabled, and (E)OSD.
Possible values:
``default`` (default)
Use ``D3DPOOL_DEFAULT``, with a ``D3DPOOL_SYSTEMMEM`` texture for
locking. If the driver supports ``D3DDEVCAPS_TEXTURESYSTEMMEMORY``,
``D3DPOOL_SYSTEMMEM`` is used directly.
``default-pool``
Use ``D3DPOOL_DEFAULT``. (Like ``default``, but never use a
shadow-texture.)
``default-pool-shadow``
Use ``D3DPOOL_DEFAULT``, with a ``D3DPOOL_SYSTEMMEM`` texture for
locking. (Like ``default``, but always force the shadow-texture.)
``managed``
Use ``D3DPOOL_MANAGED``.
``scratch``
Use ``D3DPOOL_SCRATCH``, with a ``D3DPOOL_SYSTEMMEM`` texture for
locking.
``--vo-direct3d-swap-discard``
Use ``D3DSWAPEFFECT_DISCARD``, which might be faster.
Might be slower too, as it must(?) clear every frame.
``--vo-direct3d-exact-backbuffer``
Always resize the backbuffer to window size.
``gpu``
General purpose, customizable, GPU-accelerated video output driver. It
supports extended scaling methods, dithering, color management, custom
shaders, HDR, and more.
See `GPU renderer options`_ for options specific to this VO.
By default, it tries to use fast and fail-safe settings. Use the
``gpu-hq`` profile to use this driver with defaults set to high quality
rendering. The profile can be applied with ``--profile=gpu-hq`` and its
contents can be viewed with ``--show-profile=gpu-hq``.
This VO abstracts over several possible graphics APIs and windowing
contexts, which can be influenced using the ``--gpu-api`` and
``--gpu-context`` options.
Hardware decoding over OpenGL-interop is supported to some degree. Note
that in this mode, some corner case might not be gracefully handled, and
color space conversion and chroma upsampling is generally in the hand of
the hardware decoder APIs.
``gpu`` makes use of FBOs by default. Sometimes you can achieve better
quality or performance by changing the ``--fbo-format`` option to
``rgb16f``, ``rgb32f`` or ``rgb``. Known problems include Mesa/Intel not
accepting ``rgb16``, Mesa sometimes not being compiled with float texture
support, and some macOS setups being very slow with ``rgb16`` but fast
with ``rgb32f``. If you have problems, you can also try enabling the
``--gpu-dumb-mode=yes`` option.
``gpu-next``
Experimental video renderer based on ``libplacebo``. This supports almost
the same set of features as ``--vo=gpu``. See `GPU renderer options`_ for a
list.
Currently, this only supports ``--gpu-api=vulkan``, and no hardware
decoding. Unlike ``--vo=gpu``, the FBO formats are not tunable, but you can
still set ``--gpu-dumb-mode=yes`` to forcibly disable their use.
Should generally be faster and higher quality, but some features may still
be missing or misbehave. Expect (and report!) bugs.
``sdl``
SDL 2.0+ Render video output driver, depending on system with or without
hardware acceleration. Should work on all platforms supported by SDL 2.0.
For tuning, refer to your copy of the file ``SDL_hints.h``.
.. note:: This driver is for compatibility with systems that don't provide
proper graphics drivers.
The following global options are supported by this video output:
``--sdl-sw``
Continue even if a software renderer is detected.
``--sdl-switch-mode``
Instruct SDL to switch the monitor video mode when going fullscreen.
``vaapi``
Intel VA API video output driver with support for hardware decoding. Note
that there is absolutely no reason to use this, other than compatibility.
This is low quality, and has issues with OSD.
.. note:: This driver is for compatibility with crappy systems. You can
use vaapi hardware decoding with ``--vo=gpu`` too.
The following global options are supported by this video output:
``--vo-vaapi-scaling=<algorithm>``
default
Driver default (mpv default as well).
fast
Fast, but low quality.
hq
Unspecified driver dependent high-quality scaling, slow.
nla
``non-linear anamorphic scaling``
``--vo-vaapi-deint-mode=<mode>``
Select deinterlacing algorithm. Note that by default deinterlacing is
initially always off, and needs to be enabled with the ``d`` key
(default key binding for ``cycle deinterlace``).
This option doesn't apply if libva supports video post processing (vpp).
In this case, the default for ``deint-mode`` is ``no``, and enabling
deinterlacing via user interaction using the methods mentioned above
actually inserts the ``vavpp`` video filter. If vpp is not actually
supported with the libva backend in use, you can use this option to
forcibly enable VO based deinterlacing.
no
Don't allow deinterlacing (default for newer libva).
first-field
Show only first field.
bob
bob deinterlacing (default for older libva).
``--vo-vaapi-scaled-osd=<yes|no>``
If enabled, then the OSD is rendered at video resolution and scaled to
display resolution. By default, this is disabled, and the OSD is
rendered at display resolution if the driver supports it.
``null``
Produces no video output. Useful for benchmarking.
Usually, it's better to disable video with ``--no-video`` instead.
The following global options are supported by this video output:
``--vo-null-fps=<value>``
Simulate display FPS. This artificially limits how many frames the
VO accepts per second.
``caca``
Color ASCII art video output driver that works on a text console.
.. note:: This driver is a joke.
``tct``
Color Unicode art video output driver that works on a text console.
By default depends on support of true color by modern terminals to display
the images at full color range, but 256-colors output is also supported (see
below). On Windows it requires an ansi terminal such as mintty.
Since mpv 0.30.0, you may need to use ``--profile=sw-fast`` to get decent
performance.
Note: the TCT image output is not synchronized with other terminal output
from mpv, which can lead to broken images. The options ``--no-terminal`` or
``--really-quiet`` can help with that.
``--vo-tct-algo=<algo>``
Select how to write the pixels to the terminal.
half-blocks
Uses unicode LOWER HALF BLOCK character to achieve higher vertical
resolution. (Default.)
plain
Uses spaces. Causes vertical resolution to drop twofolds, but in
theory works in more places.
``--vo-tct-width=<width>`` ``--vo-tct-height=<height>``
Assume the terminal has the specified character width and/or height.
These default to 80x25 if the terminal size cannot be determined.
``--vo-tct-256=<yes|no>`` (default: no)
Use 256 colors - for terminals which don't support true color.
``sixel``
Graphical output for the terminal, using sixels. Tested with ``mlterm`` and
``xterm``.
Note: the Sixel image output is not synchronized with other terminal output
from mpv, which can lead to broken images. The option ``--really-quiet``
can help with that, and is recommended.
You may need to use ``--profile=sw-fast`` to get decent performance.
Note: at the time of writing, ``xterm`` does not enable sixel by default -
launching it as ``xterm -ti 340`` is one way to enable it. Also, ``xterm``
does not display images bigger than 1000x1000 pixels by default.
To render and align sixel images correctly, mpv needs to know the terminal
size both in cells and in pixels. By default it tries to use values which
the terminal reports, however, due to differences between terminals this is
an error-prone process which cannot be automated with certainty - some
terminals report the size in pixels including the padding - e.g. ``xterm``,
while others report the actual usable number of pixels - like ``mlterm``.
Additionally, they may behave differently when maximized or in fullscreen,
and mpv cannot detect this state using standard methods.
Sixel size and alignment options:
``--vo-sixel-cols=<columns>``, ``--vo-sixel-rows=<rows>`` (default: 0)
Specify the terminal size in character cells, otherwise (0) read it
from the terminal, or fall back to 80x25. Note that mpv doesn't use the
the last row with sixel because this seems to result in scrolling.
``--vo-sixel-width=<width>``, ``--vo-sixel-height=<height>`` (default: 0)
Specify the available size in pixels, otherwise (0) read it from the
terminal, or fall back to 320x240. Other than excluding the last line,
the height is also further rounded down to a multiple of 6 (sixel unit
height) to avoid overflowing below the designated size.
``--vo-sixel-left=<col>``, ``--vo-sixel-top=<row>`` (default: 0)
Specify the position in character cells where the image starts (1 is
the first column or row). If 0 (default) then try to automatically
determine it according to the other values and the image aspect ratio
and zoom.
``--vo-sixel-pad-x=<pad_x>``, ``--vo-sixel-pad-y=<pad_y>`` (default: -1)
Used only when mpv reads the size in pixels from the terminal.
Specify the number of padding pixels (on one side) which are included
at the size which the terminal reports. If -1 (default) then the number
of pixels is rounded down to a multiple of number of cells (per axis),
to take into account padding at the report - this only works correctly
when the overall padding per axis is smaller than the number of cells.
``--vo-sixel-exit-clear=<yes|no>`` (default: yes)
Whether or not to clear the terminal on quit. When set to no - the last
sixel image stays on screen after quit, with the cursor following it.
Sixel image quality options:
``--vo-sixel-dither=<algo>``
Selects the dither algorithm which libsixel should apply.
Can be one of the below list as per libsixel's documentation.
auto (Default)
Let libsixel choose the dithering method.
none
Don't diffuse
atkinson
Diffuse with Bill Atkinson's method.
fs
Diffuse with Floyd-Steinberg method
jajuni
Diffuse with Jarvis, Judice & Ninke method
stucki
Diffuse with Stucki's method
burkes
Diffuse with Burkes' method
arithmetic
Positionally stable arithmetic dither
xor
Positionally stable arithmetic xor based dither
``--vo-sixel-fixedpalette=<yes|no>`` (default: yes)
Use libsixel's built-in static palette using the XTERM256 profile
for dither. Fixed palette uses 256 colors for dithering. Note that
using ``no`` (at the time of writing) will slow down ``xterm``.
``--vo-sixel-reqcolors=<colors>`` (default: 256)
Has no effect with fixed palette. Set up libsixel to use required
number of colors for dynamic palette. This value depends on the
terminal emulator as well. Xterm supports 256 colors. Can set this to
a lower value for faster performance.
``--vo-sixel-threshold=<threshold>`` (default: -1)
Has no effect with fixed palette. Defines the threshold to change the
palette - as percentage of the number of colors, e.g. 20 will change
the palette when the number of colors changed by 20%. It's a simple
measure to reduce the number of palette changes, because it can be slow
in some terminals (``xterm``). The default (-1) will choose a palette
on every frame and will have better quality.
``image``
Output each frame into an image file in the current directory. Each file
takes the frame number padded with leading zeros as name.
The following global options are supported by this video output:
``--vo-image-format=<format>``
Select the image file format.
jpg
JPEG files, extension .jpg. (Default.)
jpeg
JPEG files, extension .jpeg.
png
PNG files.
webp
WebP files.
``--vo-image-png-compression=<0-9>``
PNG compression factor (speed vs. file size tradeoff) (default: 7)
``--vo-image-png-filter=<0-5>``
Filter applied prior to PNG compression (0 = none; 1 = sub; 2 = up;
3 = average; 4 = Paeth; 5 = mixed) (default: 5)
``--vo-image-jpeg-quality=<0-100>``
JPEG quality factor (default: 90)
``--vo-image-jpeg-optimize=<0-100>``
JPEG optimization factor (default: 100)
``--vo-image-webp-lossless=<yes|no>``
Enable writing lossless WebP files (default: no)
``--vo-image-webp-quality=<0-100>``
WebP quality (default: 75)
``--vo-image-webp-compression=<0-6>``
WebP compression factor (default: 4)
``--vo-image-outdir=<dirname>``
Specify the directory to save the image files to (default: ``./``).
``libmpv``
For use with libmpv direct embedding. As a special case, on macOS it
is used like a normal VO within mpv (cocoa-cb). Otherwise useless in any
other contexts.
(See ``<mpv/render.h>``.)
This also supports many of the options the ``gpu`` VO has, depending on the
backend.
``rpi`` (Raspberry Pi)
Native video output on the Raspberry Pi using the MMAL API.
This is deprecated. Use ``--vo=gpu`` instead, which is the default and
provides the same functionality. The ``rpi`` VO will be removed in
mpv 0.23.0. Its functionality was folded into --vo=gpu, which now uses
RPI hardware decoding by treating it as a hardware overlay (without applying
GL filtering). Also to be changed in 0.23.0: the --fs flag will be reset to
"no" by default (like on the other platforms).
The following deprecated global options are supported by this video output:
``--rpi-display=<number>``
Select the display number on which the video overlay should be shown
(default: 0).
``--rpi-layer=<number>``
Select the dispmanx layer on which the video overlay should be shown
(default: -10). Note that mpv will also use the 2 layers above the
selected layer, to handle the window background and OSD. Actual video
rendering will happen on the layer above the selected layer.
``--rpi-background=<yes|no>``
Whether to render a black background behind the video (default: no).
Normally it's better to kill the console framebuffer instead, which
gives better performance.
``--rpi-osd=<yes|no>``
Enabled by default. If disabled with ``no``, no OSD layer is created.
This also means there will be no subtitles rendered.
``drm`` (Direct Rendering Manager)
Video output driver using Kernel Mode Setting / Direct Rendering Manager.
Should be used when one doesn't want to install full-blown graphical
environment (e.g. no X). Does not support hardware acceleration (if you
need this, check the ``drm`` backend for ``gpu`` VO).
Since mpv 0.30.0, you may need to use ``--profile=sw-fast`` to get decent
performance.
The following global options are supported by this video output:
``--drm-connector=[<gpu_number>.]<name>``
Select the connector to use (usually this is a monitor.) If ``<name>``
is empty or ``auto``, mpv renders the output on the first available
connector. Use ``--drm-connector=help`` to get a list of available
connectors. The ``<gpu_number>`` argument can be used to disambiguate
multiple graphic cards, but is deprecated in favor of ``--drm-device``.
(default: empty)
``--drm-device=<path>``
Select the DRM device file to use. If specified this overrides automatic
card selection and any card number specified ``--drm-connector``.
(default: empty)
``--drm-mode=<preferred|highest|N|WxH[@R]>``
Mode to use (resolution and frame rate).
Possible values:
:preferred: Use the preferred mode for the screen on the selected
connector. (default)
:highest: Use the mode with the highest resolution available on the
selected connector.
:N: Select mode by index.
:WxH[@R]: Specify mode by width, height, and optionally refresh rate.
In case several modes match, selects the mode that comes
first in the EDID list of modes.
Use ``--drm-mode=help`` to get a list of available modes for all active
connectors.
``--drm-atomic=<no|auto>``
Toggle use of atomic modesetting. Mostly useful for debugging.
:no: Use legacy modesetting.
:auto: Use atomic modesetting, falling back to legacy modesetting if
not available. (default)
Note: Only affects ``gpu-context=drm``. ``vo=drm`` supports legacy
modesetting only.
``--drm-draw-plane=<primary|overlay|N>``
Select the DRM plane to which video and OSD is drawn to, under normal
circumstances. The plane can be specified as ``primary``, which will
pick the first applicable primary plane; ``overlay``, which will pick
the first applicable overlay plane; or by index. The index is zero
based, and related to the CRTC.
(default: primary)
When using this option with the drmprime-drm hwdec interop, only the OSD
is rendered to this plane.
``--drm-drmprime-video-plane=<primary|overlay|N>``
Select the DRM plane to use for video with the drmprime-drm hwdec
interop (used by e.g. the rkmpp hwdec on RockChip SoCs, and v4l2 hwdec:s
on various other SoC:s). The plane is unused otherwise. This option
accepts the same values as ``--drm-draw-plane``. (default: overlay)
To be able to successfully play 4K video on various SoCs you might need
to set ``--drm-draw-plane=overlay --drm-drmprime-video-plane=primary``
and setting ``--drm-draw-surface-size=1920x1080``, to render the OSD at a
lower resolution (the video when handled by the hwdec will be on the
drmprime-video plane and at full 4K resolution)
``--drm-format=<xrgb8888|xrgb2101010>``
Select the DRM format to use (default: xrgb8888). This allows you to
choose the bit depth of the DRM mode. xrgb8888 is your usual 24 bit per
pixel/8 bits per channel packed RGB format with 8 bits of padding.
xrgb2101010 is a packed 30 bits per pixel/10 bits per channel packed RGB
format with 2 bits of padding.
There are cases when xrgb2101010 will work with the ``drm`` VO, but not
with the ``drm`` backend for the ``gpu`` VO. This is because with the
``gpu`` VO, in addition to requiring support in your DRM driver,
requires support for xrgb2101010 in your EGL driver
``--drm-draw-surface-size=<[WxH]>``
Sets the size of the surface used on the draw plane. The surface will
then be upscaled to the current screen resolution. This option can be
useful when used together with the drmprime-drm hwdec interop at high
resolutions, as it allows scaling the draw plane (which in this case
only handles the OSD) down to a size the GPU can handle.
When used without the drmprime-drm hwdec interop this option will just
cause the video to get rendered at a different resolution and then
scaled to screen size.
Note: this option is only available with DRM atomic support.
(default: display resolution)
``mediacodec_embed`` (Android)
Renders ``IMGFMT_MEDIACODEC`` frames directly to an ``android.view.Surface``.
Requires ``--hwdec=mediacodec`` for hardware decoding, along with
``--vo=mediacodec_embed`` and ``--wid=(intptr_t)(*android.view.Surface)``.
Since this video output driver uses native decoding and rendering routines,
many of mpv's features (subtitle rendering, OSD/OSC, video filters, etc)
are not available with this driver.
To use hardware decoding with ``--vo=gpu`` instead, use
``--hwdec=mediacodec-copy`` along with ``--gpu-context=android``.
``wlshm`` (Wayland only)
Shared memory video output driver without hardware acceleration that works
whenever Wayland is present.
Since mpv 0.30.0, you may need to use ``--profile=sw-fast`` to get decent
performance.
.. note:: This is a fallback only, and should not be normally used.