GBLURS
======

A sh and python interface to all Gaussian blurs.

Wait, wait. I'm worried what you just heard was, "an interface to a lot of
Gaussian blurs".  What I said was "an interface to all the Gaussian blurs."
Do you understand?

This program lets you run all Gaussian blurs with a unified interface.  The
parameter σ is scaled to mean the same thing across all implementations.  By
default the boundary conditions are whatever each implementation does by
default.  A facility for arbitrary boundary condtions is given as a wrapper.

The program has no dependencies in itself, but calling it with each method
requires that you have installed the corresponding dependency.  For example, if
you don't have "gimp", then gimps' Gaussian blur won't be available.

Any publicly available Gaussian blur that has no interface here is considered a
bug.


shell usage
-----------

gblurs borelli -i in.png -o out.npy -s 14
gblurs skimage -i in.png -o out.npy -s 14
gblurs opencv  -i in.png -o out.npy -s 14
gblurs torch   -i in.png -o out.npy -s 14


python usage
------------

! pip install gblurs

# via the universal accessor G
from gblurs import G
y = G("borelli", x, 14)
y = G("skimage", x, 14)
y = G("opencv", x, 14)
y = G("torch", x, 14)

# via individual functions
from gblurs import gblur_borelli # etc


list of all blurs
-----------------

ID        | implementation
----------+---------------------------------------------------------------
borelli   | built-in, using numpy.fft.fft2
torch     | torchvision.transforms.GaussianBlur(kernel_size=(n,n) sigma=s)
tfm       | tensorflow_models.vision.augment.gaussian_filter2d(x, n, s)
keras     | tensorflow keras RandomGaussianBlur
pix       | dm_pix.gaussia_blur(x, s, n)   # part of JAX
pillow    | x.filter(PIL.ImageFilger.GaussianBlur(s))
scipy     | scipy.ndimage.gaussian_filter(x, sigma=(s,s,0))
opencv    | cv2.GaussianBlur(x, (0,0), s)
skimage   | skimage.filters.gaussian(x, sigma=s, channel_axis=-1)
vips      | x.gaussblur(s)
ymscript  | ymscript.gauss(x, s)
imagick   | mogrify -gaussian 0x$s
gmic      | gmic -blur $s
ffmpeg    | ffmpeg -filter_complex "gblur=sigma=$s"
gimp      | (plug-in-gauss 1 img layer {s} {s} 0)
krita     | app.filter("gaussian blur")  # inside krita scripter
rust      | imagecli -p "gaussian $s"
octave    | imsmooth(x, "Gaussian", s);
julia     | imfilter(x, Kernel.gaussian(s))



Missing  (considered as bugs)
-----------------------------

ID        | status
----------+--------------------------------------------
darktable | trouble with b64encode inside xml filter file
pnm       | not yet implemented
megawave  | not yet implemented
scilab    | not yet implemented