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Thinning[image]

finds the skeletons of foreground regions in image by applying morphological thinning until convergence.

Thinning[image,n]

performs n iterations of morphological thinning.

Thinning[image,n,t]

treats values above t as foreground.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Options  
Method  
Padding  
Applications  
Neat Examples  
See Also
Related Guides
History
Cite this Page

Thinning

Thinning[image]

finds the skeletons of foreground regions in image by applying morphological thinning until convergence.

Thinning[image,n]

performs n iterations of morphological thinning.

Thinning[image,n,t]

treats values above t as foreground.

Details and Options

  • Thinning[image,…] yields a binary image in which pixels representing the morphological skeleton have value 1 and others have value 0.
  • Thinning[image] is equivalent to Thinning[image,Infinity].
  • Thinning works with binary, grayscale, and arbitrary multichannel images, as well as real matrices.
  • Thinning takes a Padding option that specifies the values to assume for pixels outside the image. The default setting is Padding->0.
  • Thinning supports a Method option which specifies what thinning algorithm to be used. Possible settings include:
  • "Morphological"morphological thinning (default)
    "MedialAxis"approximate medial axis

Examples

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Basic Examples  (1)

Morphological thinning of an image:

Wolfram Language code: Thinning[[image]]

Scope  (2)

Applying the morphological thinning to a label matrix:

Wolfram Language code: Thinning[MorphologicalComponents[[image]]] //Colorize

Thinning a grayscale image using a specific foreground threshold:

Wolfram Language code: Thinning[[image], Infinity, 0.2]

Options  (3)

Method  (1)

Find the approximate medial axis:

Wolfram Language code: Thinning[[image], Method -> "MedialAxis"]

Padding  (2)

The padding value affects objects adjacent to the boundary:

Wolfram Language code: Thinning[[image], Padding -> #]& /@ {0, 1}

Pad with the foreground value:

Wolfram Language code: Thinning[[image], Padding -> 1]

Applications  (2)

Simplify features in a fingerprint image:

Wolfram Language code: Thinning[[image]]

Use the image skeleton to construct a graph:

Wolfram Language code: t = Thinning[[image], Infinity, 0.9]
Wolfram Language code: MorphologicalGraph[t]

Neat Examples  (2)

Extract possible paths through a maze:

Wolfram Language code: Pruning[Thinning[[image], Padding -> 1], Padding -> 1]

Find the approximate Voronoi diagram of the foreground objects:

Wolfram Language code: i = [image];ImageAdd[i, ColorCombine[{Thinning[ColorNegate@i, Padding -> 1], i, i}]]
Wolfram Research (2010), Thinning, Wolfram Language function, https://reference.wolfram.com/language/ref/Thinning.html.

Text

Wolfram Research (2010), Thinning, Wolfram Language function, https://reference.wolfram.com/language/ref/Thinning.html.

CMS

Wolfram Language. 2010. "Thinning." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/Thinning.html.

APA

Wolfram Language. (2010). Thinning. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/Thinning.html

BibTeX

@misc{reference.wolfram_2026_thinning, author="Wolfram Research", title="{Thinning}", year="2010", howpublished="\url{https://reference.wolfram.com/language/ref/Thinning.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_thinning, organization={Wolfram Research}, title={Thinning}, year={2010}, url={https://reference.wolfram.com/language/ref/Thinning.html}, note=[Accessed: 12-June-2026]}