Hi,
I would like to propose a new denoising method for dt : the Total
Variation. It plays in the same category as the bilateral denoising :
* it smoothens surfaces while retaining edges
* it's very efficient to recover chroma noise and noise in bokeh areas
without affecting too much the in-focus areas
* but it could be more computing efficient.
A researcher has published an article
<http://www.ipol.im/pub/art/2016/141/> comparing several sub-methods to
do so (with various regularizations) and released his C++ code
<http://www.ipol.im/pub/art/2016/141/DMSC_TVdenoising.tgz> under the
GPL. Regular people can test the algorithm online
<http://demo.ipol.im/demo/141/>with their own pictures. The rest of the
details (and more candies) are on his page :
https://joandurangrimalt.wordpress.com/software/
The background of this method is to minimize the energy of the picture,
hence the noise, defined as the integral of the gradients over the
picture. I have succesfully achieved a faster gradient estimation using
a 2D convolution with separable filters (same way as the Sobel operator)
with this research <https://cdn.intechopen.com/pdfs-wm/39346.pdf>.
I don't have time now to work on integrating this myself, as I'm already
buisy working on the blind deconvolution and stuggling with C, but I
believe it would be a great add-on to offer a more efficient alternative
to the bilateral filter, and all the maths and C libs are already there,
so most of the work would be UI.
Anybody willing to work on that ?
Thanks !
PS : there is also a non-local total-variation regularization available,
able to both denoise and reconstruct details by inpainting, but it's
just maths and no GPL code for now :
* https://hal.archives-ouvertes.fr/hal-01342111/
*
https://joandurangrimalt.wordpress.com/research/novel-tv-based-regularization/
--
*Aurélien PIERRE*
aurelienpierre.com <http://aurelienpierre.com>
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