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RidgeFilter

RidgeFilter[image]
computes a measure for the presence of a ridge for each pixel in image.
RidgeFilter
uses the specified ridge scale .
  • RidgeFilter computes the main principal curvature at each pixel.
  • The main principal curvature orthogonal to a ridge is given by the main negative eigenvalue of the Hessian matrix.
  • In RidgeFilter, is the scale of the ridges that is used to compute the derivatives in the Hessian.
  • RidgeFilter works with arbitrary grayscale or multichannel images, operating separately on each channel.
  • RidgeFilter returns a real image of the same dimensions as image.
  • RidgeFilter[array] computes the ridges in a two-dimensional array.
  • RidgeFilter supports the following options to compute the Hessian matrix and the main principal curvature:
InterpolationOrderAutomaticinterpolation order
Padding"Fixed"padding method
  • The Padding option accepts the settings , , , , or a numeric value. A list of two settings can specify different paddings for each dimension.
Detect lines of a given width in a noisy image with uneven brightness:
Find the mountain ridges in a terrain elevation raster:
Enhance the strokes of handwritten characters:
Detect lines of a given width in a noisy image with uneven brightness:
In[1]:=
Click for copyable input
Out[1]=
 
Find the mountain ridges in a terrain elevation raster:
In[1]:=
Click for copyable input
Out[1]=
 
Enhance the strokes of handwritten characters:
In[1]:=
Click for copyable input
Out[1]=
Extract lines of a given thickness:
Find the red ridges in a microscopic photo of a Yucca leaf:
Extract the thin walls:
New in 8