MureDenoise and Nearest Neighbor

alphascorpi

Member
Dec 28, 2013
21
1
Hi
I have found in the documentation of the MureDenoise script a hint to the interpolation method:
" The script provides maximum output quality when Nearest Neighbor is used".

In the documentation of the StarAlign process you can read:
" Nearest neighbor produces a useless registered image with obvious lack of subpixel accuracy and jagged stars. "

And now what is correct?
Thanks Ed
 

dld

Well-known member
Sep 24, 2017
173
20
Both :)

Nearest neighbor interpolation has the benefit of preserving the noise distribution of the original frames thus fulfilling MureDenoise requirements. But as an interpolation algorithm is not that good.
 

mschuster

PTeam Member
Nov 27, 2011
1,137
4
San Francisco
MureDenoise works well on the interpolation options listed in its dialog parameter, but is in fact most accurate for Nearest Neighbor.

Regarding Nearest Neighbor generating useless images, it is not useless on my projects. Here is an example of two choices. Which would you choose? Left is Lanczos-4, right is Nearest Neighbor.

 
Last edited:

ngc1535

PTeam Member
Feb 1, 2014
556
76
AdamBlockStudios.com
For large numbers of images, Nearest Neighbor is a super excellent way to combine images (perhaps when oversampled?). However, in testing with Lanczos resampling algorithm- the differences are small. The weird thing about nearest neighbor is that a close examination of the image (assuming not scaling or rotation) will show regions of the image that shift an integer pixel. On small scales you will not notice- but on larger scales it is kinda freaky.

-adam
 

alphascorpi

Member
Dec 28, 2013
21
1
MureDenoise works well on the interpolation options listed in its dialog parameter, but is in fact most accurate for Nearest Neighbor.

Regarding Nearest Neighbor generating useless images, it is not useless on my projects. Here is an example of two choices. Which would you choose? Left is Lanczos-4, right is Nearest Neighbor.

MureDenoise works well on the interpolation options listed in its dialog parameter, but is in fact most accurate for Nearest Neighbor.

Regarding Nearest Neighbor generating useless images, it is not useless on my projects. Here is an example of two choices. Which would you choose? Left is Lanczos-4, right is Nearest Neighbor.

Hi Mike
Thanks for this two images. To your question: I would choose the right one :)
I know that MD should be used after the integration. Can you tell me if there is a preference to use MD before or after DBE?
 

alphascorpi

Member
Dec 28, 2013
21
1
Thanks for your help.
I have learned that
1. Nearest Neighbor is a valuable choice in StarAlign if you decide to use MureDenoise
2. Mure Denoise works best with Nearest Neighbor
3. Use MureDenoise after integration and before further steps like DynamicCrop and DBE.
Ed
 
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