skimage 0.17.2

NotesParametersReturnsBackRef
frangi(image, sigmas=range(1, 10, 2), scale_range=None, scale_step=None, alpha=0.5, beta=0.5, gamma=15, black_ridges=True, mode='reflect', cval=0)

This filter can be used to detect continuous ridges, e.g. vessels, wrinkles, rivers. It can be used to calculate the fraction of the whole image containing such objects.

Defined only for 2-D and 3-D images. Calculates the eigenvectors of the Hessian to compute the similarity of an image region to vessels, according to the method described in .

Notes

Written by Marc Schrijver, November 2001 Re-Written by D. J. Kroon, University of Twente, May 2009, Adoption of 3D version from D. G. Ellis, Januar 20017,

Parameters

image : (N, M[, P]) ndarray

Array with input image data.

sigmas : iterable of floats, optional

Sigmas used as scales of filter, i.e., np.arange(scale_range[0], scale_range[1], scale_step)

scale_range : 2-tuple of floats, optional

The range of sigmas used.

scale_step : float, optional

Step size between sigmas.

alpha : float, optional

Frangi correction constant that adjusts the filter's sensitivity to deviation from a plate-like structure.

beta : float, optional

Frangi correction constant that adjusts the filter's sensitivity to deviation from a blob-like structure.

gamma : float, optional

Frangi correction constant that adjusts the filter's sensitivity to areas of high variance/texture/structure.

black_ridges : boolean, optional

When True (the default), the filter detects black ridges; when False, it detects white ridges.

mode : {'constant', 'reflect', 'wrap', 'nearest', 'mirror'}, optional

How to handle values outside the image borders.

cval : float, optional

Used in conjunction with mode 'constant', the value outside the image boundaries.

Returns

out : (N, M[, P]) ndarray

Filtered image (maximum of pixels across all scales).

Filter an image with the Frangi vesselness filter.

See Also

hessian
meijering
sato

Examples

See :

Back References

The following pages refer to to this document either explicitly or contain code examples using this.

skimage.filters.ridges.hessian skimage.filters.ridges.meijering skimage.filters.ridges.sato

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