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NonlocalMeansFilter[image,r]

applies a nonlocal means filter to image by comparing a range r neighborhood to its nearby neighborhoods.

NonlocalMeansFilter[image,r,ns]

assumes an additive noise power value ns for comparing neighborhoods.

NonlocalMeansFilter[image,r,ns,w]

compares neighborhoods in a range w window.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Data  
Parameters  
Options  
Padding  
Applications  
Properties & Relations  
See Also
Related Guides
History
Cite this Page

NonlocalMeansFilter

NonlocalMeansFilter[image,r]

applies a nonlocal means filter to image by comparing a range r neighborhood to its nearby neighborhoods.

NonlocalMeansFilter[image,r,ns]

assumes an additive noise power value ns for comparing neighborhoods.

NonlocalMeansFilter[image,r,ns,w]

compares neighborhoods in a range w window.

Details and Options

Examples

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Basic Examples  (1)

Filter a noisy grayscale image:

Wolfram Language code: NonlocalMeansFilter[[image], 1]

Scope  (5)

Data  (2)

Filtering of a grayscale image:

Wolfram Language code: NonlocalMeansFilter[[image], 1]

Filter a noisy color image:

Wolfram Language code: NonlocalMeansFilter[[image], 1, .01]

Parameters  (3)

Specify the range:

Wolfram Language code: NonlocalMeansFilter[[image], #]& /@ {.5, 5}

Use the default additive noise power setting:

Wolfram Language code: NonlocalMeansFilter[[image], 1]

Use a custom noise power setting:

Wolfram Language code: NonlocalMeansFilter[[image], 1, 0.025]

The default range window is 5r:

Wolfram Language code: NonlocalMeansFilter[[image], 1, .05, 5]

Use different window sizes:

Wolfram Language code: NonlocalMeansFilter[[image], 1, 0.05, #]& /@ {2, 10}

Options  (2)

Padding  (2)

By default, a "Fixed" padding is used:

Wolfram Language code: NonlocalMeansFilter[[image], 10]

Specify a custom padding:

Wolfram Language code: NonlocalMeansFilter[[image], 10, Padding -> 0]

Applications  (3)

Remove Gaussian color noise from an image:

Wolfram Language code: i = [image]; NonlocalMeansFilter[i, 1]

Use a NonlocalMeansFilter to remove smaller stars from an astronomical image:

Wolfram Language code: NonlocalMeansFilter[[image], 1, .01]

Unsharp masking using NonlocalMeansFilter:

Wolfram Language code: i = [image]; 2i - NonlocalMeansFilter[i, 1, .1]

Properties & Relations  (1)

NonlocalMeansFilter returns an image of the same type as image:

Wolfram Language code: ImageType /@ {[image], NonlocalMeansFilter[[image], 1]}
Wolfram Research (2012), NonlocalMeansFilter, Wolfram Language function, https://reference.wolfram.com/language/ref/NonlocalMeansFilter.html.

Text

Wolfram Research (2012), NonlocalMeansFilter, Wolfram Language function, https://reference.wolfram.com/language/ref/NonlocalMeansFilter.html.

CMS

Wolfram Language. 2012. "NonlocalMeansFilter." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/NonlocalMeansFilter.html.

APA

Wolfram Language. (2012). NonlocalMeansFilter. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/NonlocalMeansFilter.html

BibTeX

@misc{reference.wolfram_2026_nonlocalmeansfilter, author="Wolfram Research", title="{NonlocalMeansFilter}", year="2012", howpublished="\url{https://reference.wolfram.com/language/ref/NonlocalMeansFilter.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_nonlocalmeansfilter, organization={Wolfram Research}, title={NonlocalMeansFilter}, year={2012}, url={https://reference.wolfram.com/language/ref/NonlocalMeansFilter.html}, note=[Accessed: 13-June-2026]}