[darktable-dev] Re: denoise profile non local means: neighborhood parameter

Hello Here is a little update on what I have done recently on denoising. My work on a "new" raw denoise module is still ongoing, but it takes a lot of time (as expected), as I have to try various things before getting correct ones. So no news on this side. Yet, I found a quicker and easier way to

[darktable-dev] Re: denoise profile non local means: neighborhood parameter

Thank you Aurélien, that is a great answer. I think I will try to incorporate this in the weight computation of non local means to use only "non noisy" pixels in the computations of the weights, in addition to trying to use this as a (parametric?) mask. rawfiner Le samedi 21 juillet 2018,

Re: [darktable-dev] Re: denoise profile non local means: neighborhood parameter

I went through Aurélien's study again I wonder why the result of TV is divided by 4 (in case of 8 neighbors, "out[ i, j, k] /= 4.") I guess it is kind of a normalisation. But as we divided the differences along diagonals by sqrt(2), the maximum achievable (supposing the values of the image are in

Re: [darktable-dev] Re: denoise profile non local means: neighborhood parameter

Thank you for all these explanations! Seems promising to me. Cheers, rawfiner 2018-07-01 21:26 GMT+02:00 Aurélien Pierre : > You're welcome ;-) > > That's true : the multiplication is equivalent to an "AND" operation, the > resulting mask has non-zero values where both TV AND Laplacian masks

Re: [darktable-dev] Re: denoise profile non local means: neighborhood parameter

You're welcome ;-) That's true : the multiplication is equivalent to an "AND" operation, the resulting mask has non-zero values where both TV AND Laplacian masks has non-zero values, which - from my tests - is where the real noise is. That is because TV alone is too sensitive : when the image is

Re: [darktable-dev] Re: denoise profile non local means: neighborhood parameter

Thank you for this study Aurélien As far as I understand, TV and Laplacians are complementary as they detect noise in different regions of the image (noise in sharp edge for Laplacian, noise elsewhere for TV). Though, I do not understand why you multiply the TV and Laplacian results to get the

Re: [darktable-dev] Re: denoise profile non local means: neighborhood parameter

Hi, I have done experiments on that matter and took the opportunity to correct/test further my code. So here are my attempts to code a noise mask and a sharpness mask with total variation and laplacian norms :

[darktable-dev] Re: denoise profile non local means: neighborhood parameter

Le dimanche 17 juin 2018, Aurélien Pierre a écrit : > > > Le 13/06/2018 à 17:31, rawfiner a écrit : > > > > Le mercredi 13 juin 2018, Aurélien Pierre a > écrit : > >> >> >>> On Thu, Jun 14, 2018 at 12:23 AM, Aurélien Pierre >>> wrote: >>> > Hi, >>> > >>> > The problem of a 2-passes denoising

Re: [darktable-dev] Re: denoise profile non local means: neighborhood parameter

Le 13/06/2018 à 17:31, rawfiner a écrit : > > > Le mercredi 13 juin 2018, Aurélien Pierre > a écrit : > > >> >> On Thu, Jun 14, 2018 at 12:23 AM, Aurélien Pierre >> > > wrote: >> > Hi, >>

[darktable-dev] Re: denoise profile non local means: neighborhood parameter

Here are some of the RAW files I use to test the changes I make to denoising modules (including the one I used as an exemple in the beginning of this conversation): https://drive.google.com/open?id=11LxZWpZbS66m7vFdcoIHNTiG20JnwlJT The reference-jpg folder contains the JPGs produced by the camera

[darktable-dev] Re: denoise profile non local means: neighborhood parameter

Le mercredi 13 juin 2018, Aurélien Pierre a écrit : > > >> On Thu, Jun 14, 2018 at 12:23 AM, Aurélien Pierre >> wrote: >> > Hi, >> > >> > The problem of a 2-passes denoising method involving 2 differents >> > algorithms, the later applied where the former failed, could be the >> grain >> >

Re: [darktable-dev] Re: denoise profile non local means: neighborhood parameter

Le 13/06/2018 à 14:48, rawfiner a écrit : > > Le mercredi 13 juin 2018, johannes hanika > a écrit : > > hi, > > that doesn't sound like a bad idea at all. for what it's worth, in > practice the nlmeans doesn't let any grain at all through due to the >

[darktable-dev] Re: denoise profile non local means: neighborhood parameter

Le mercredi 13 juin 2018, johannes hanika a écrit : > hi, > > that doesn't sound like a bad idea at all. for what it's worth, in > practice the nlmeans doesn't let any grain at all through due to the > piecewise constant prior that it's based on. well, only in regions > where it finds enough

[darktable-dev] Re: denoise profile non local means: neighborhood parameter

Oh ok sorry for that... rawfiner Le vendredi 26 janvier 2018, Terry Duell a écrit : > On Sat, 27 Jan 2018 05:34:24 +1100, rawfiner wrote: > > Thank you for your answer I perfectly agree with the fact that the GUI >> should not become >> overcomplicated.