computes a measure for the presence of a ridge for each pixel in image.

RidgeFilter[image, ]
uses the specified ridge scale .

Details and OptionsDetails and Options

  • 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[image, ], is the scale of the ridges that is used to compute the derivatives in the Hessian.
  • RidgeFilter[image] is equivalent to RidgeFilter[image, 1].
  • RidgeFilter works with arbitrary grayscale or multichannel images, operating separately on each channel.
  • RidgeFilter[image, ...] 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
  • Possible settings for the InterpolationOrder option are 3, 5, 7, or 9.
  • The Padding option accepts the settings , , , , or a numeric value. A list of two settings can specify different paddings for each dimension.

ExamplesExamplesopen allclose all

Basic Examples (3)Basic Examples (3)

Detect lines of a given width in a noisy image with uneven brightness:

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Find the mountain ridges in a terrain elevation raster:

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Enhance the strokes of handwritten characters:

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